# Granite surface plate/flattening/where to buy?



## ali27 (24 Jun 2010)

I have been looking for a granite surface plate
for a while now. I want to use this for accurately
flattening plane soles.

I have used float glass, but I am not happy with this.

Unfortunately the granite surface plate I need is about
20 inches long. The surface plates at this size are
almost as wide and usually 3-4 inches thick which
makes them very heavy and quite expensive(shipping)

I was wondering if somebody knows where to buy
a granite sp that is about 20 inches long but only
10 inches max wide and not so thick.

Perhaps if there is much interest in such a surface
plate maybe a vendor/seller would be interested
in offering this.

A 24/18/3 inch granite sp is about 80 kg or so. 
If such a surface plate could be sawn in two pieces
or even 3 pieces, perhaps also only 2 inches thick,
that would make such a plate much lighter(20kg or so?)
easier to use and cheaper I think. 

I am sure that a 2 inch thick granite
SP is much stiffer than an half inch thick float glass.

What do you guys think? Make any sense?

Ali


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## Karl (24 Jun 2010)

Ali - whereabouts in the country are you? I have an 18" x 3" thick granite plate that I could be persuaded to part with in exchange for some beer vouchers.

Cheers

Karl


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## ali27 (24 Jun 2010)

Karl":2qtl6vky said:


> Ali - whereabouts in the country are you? I have an 18" x 3" thick granite plate that I could be persuaded to part with in exchange for some beer vouchers.
> 
> Cheers
> 
> Karl



Hi Karl,

I live in the Netherlands(2010 world champion football!)

18 inch is unfortunately a bit too short. I want to flatten
jointers as well.

Thanks for the offer. 

You English guys love your beer! 

Ali


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## jasonB (24 Jun 2010)

Pop down to your local monumental mason and get then to cut a grave stone in half. Most granite for this type of use and worktops is machine ground to acceptable tollerance for flattening. Infact an offcut of 30mm thick granite worktop would probably do the job, get two bits bonded together if you want more thickness

Jason


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## ali27 (24 Jun 2010)

jasonB":1fkzxbdp said:


> Pop down to your local monumental mason and get then to cut a grave stone in half. Most granite for this type of use and worktops is machine ground to acceptable tollerance for flattening. Infact an offcut of 30mm thick granite worktop would probably do the job, get two bits bonded together if you want more thickness
> 
> Jason



Thnx for the tip. Are those gravestones really that flat? I think
I will be bringing my straightedge with me to check.

Ali


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## laird (25 Jun 2010)

I got a black granite name plate made for the house at a local gravestone maker. The side he planed for the lettering is flat, to engineering standards. I think your cost ill be minimal as they always have broken bits of stone lying around, too small for their usual use but perfect for you.


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## Racers (25 Jun 2010)

Hi, Ali

Here is my laping set up its just a piece of 6mm glass on my bench, as long as you stretch the abrasive tight you don't get any problems.







Pete


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## bugbear (25 Jun 2010)

Racers":133s6603 said:


> Hi, Ali
> 
> Here is my laping set up its just a piece of 6mm glass on my bench, as long as you stretch the abrasive tight you don't get any problems.
> 
> ...



How confident are you of the actual flatness of the results? What have you checked against?

BugBear (with a teensy obsession in this area...)


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## Racers (25 Jun 2010)

Hi,

Checked with a straight edge/feeler gages on a surface plate (table saw)
If you keep the grit clean with frequent vacuming and use all the width it works well.

I have done loads of planes from No3 to No8, with 60 grit you can take loads off quite quickly. 


Pete


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## bugbear (25 Jun 2010)

ali27":1oyf89nz said:


> I have been looking for a granite surface plate
> for a while now. I want to use this for accurately
> flattening plane soles.
> 
> ...



Since a granite surface plate is nowhere near big enough for lapping (*) (especially a jointer), I presume (and hope) you're using the plate as a reference.

As such, a 12" x 18" is large enough, since the diagonal is 21.6 inches.

This will suffice for everything up to a #7 (22").

The next size up is 18"x24", which will be at least twice as heavy, and possibly more, since larger plates are often thicker too.

I have seen (on various forums) proposals to get large (18x24) plates cut into multiple (e.g.) 6"x24" plates as a forum "group buy", but this has always fallen at the hurdle of cost. Getting granite custom cut is very expensive, and (especially in the USA) Enco sometimes has such cheap deals (including free delivery!) that it's simply isn't a saving.

BugBear

* Dunbar, the populariser of so-called-lapping recommends the lapping surface be 3 times as long as the plane


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## woodbloke (25 Jun 2010)

Racers":ranjobww said:


> Hi, Ali
> 
> Here is my laping set up its just a piece of 6mm glass on my bench, as long as you stretch the abrasive tight you don't get any problems.
> 
> ...


This is pretty much the same method I used...worked for me. I used 10mm glass but it doesn't make a lot of difference - Rob


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## ali27 (25 Jun 2010)

bugbear":2hj6opau said:


> ali27":2hj6opau said:
> 
> 
> > I have been looking for a granite surface plate
> ...



Hi Bugbear,

The longest plane I have is a no6 which is 18 inches long
I think. If I bought a 24 inch long surface plate I would have
some room(the diagonal) to flatten the sole on the surface plate.

A 36 inch long plate would probably be better, but as I said,
they are so bloody heavy, never mind the cost. 

Bugbear, I had seen the Enco site. Very nice prices. I wish
the shipping would be free to Europe, but I am sure it is not.

For example at Enco a 36/24/4 granite surface plate is 125 USD. If these would be sawn in 36/6/4 pieces, the cost would be 125/4=
31.25 per piece+sawing cost.

I have no idea how much the sawing would cost. shipping would
be a lot I think, about 100 dollars or so.

Axminster have one also:
http://www.axminster.co.uk/product.asp? ... e=1&jump=0
450 x 600 x 100mm

price 95GBP+50 GBP for the shipping=150GBP
This one could be sawn in 3 pieces I think.

Problem is that one still gets a 3 to 4 inch thick plate. Really
heavy plate which one doesn´t need unless.

Bugbear wouldn´t the sawing cost a lot less if the plate would be
only an inch or so thick?

A 40 inch long, 6-9 inches wide, one inch thick plate would be
great don´t you think.

Ali


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## ali27 (25 Jun 2010)

Racers":1809tahs said:


> Hi, Ali
> 
> Here is my laping set up its just a piece of 6mm glass on my bench, as long as you stretch the abrasive tight you don't get any problems.
> 
> ...



Pete, your setup looks nice. If it works for you great! For me 
the glass thing is not working. My glass plate itself is not really
flat and I notice that it does bend slightly.

Perhaps a really flat glass plate with something very flat underneath it(mdf) to support it would work. 

I prefer the granite plate tough.

Ali


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## ali27 (25 Jun 2010)

laird":1cbowu7f said:


> I got a black granite name plate made for the house at a local gravestone maker. The side he planed for the lettering is flat, to engineering standards. I think your cost ill be minimal as they always have broken bits of stone lying around, too small for their usual use but perfect for you.



Thanks for the info. I will definitely check this out.

Ali


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## bugbear (25 Jun 2010)

ali27":2xrgyeqj said:


> Axminster have one also:
> http://www.axminster.co.uk/product.asp? ... e=1&jump=0
> 450 x 600 x 100mm
> 
> ...



They're made that thick because that's the thickness you need to have the RIGIDITY for the accuracy to have meaning.

There's no point having something flat to (say) a tenth of a thou, if it can flex by (say) 4 thou under common working loads...

BugBear


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## ali27 (25 Jun 2010)

bugbear":ogyb2twh said:


> ali27":ogyb2twh said:
> 
> 
> > Axminster have one also:
> ...



True, but some people seem to have good results with
float glass that is only 1 cm thick.

I don´t know for sure, but I think an inch thick granite
is much stiffer than 1cm glass, no?

Ali


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## bugbear (25 Jun 2010)

ali27":3be1bf2x said:


> bugbear":3be1bf2x said:
> 
> 
> > ali27":3be1bf2x said:
> ...



But you asked about surface plates!

Which are both flat and rigid.

Glass is merely smooth, and as flat as the surface it's lying on.

But if you want flatness you can TRUST, get a suitable surface plate.

I've also posted my findings on lapping on a (defunct) website, herewith from the wayback machine:

http://web.archive.org/web/200605092205 ... atten.html

BugBear


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## ali27 (25 Jun 2010)

bugbear":v3502mb6 said:


> ali27":v3502mb6 said:
> 
> 
> > bugbear":v3502mb6 said:
> ...


Bugbear,

What thickness do you think is sufficient(rigid enough) to flatten plane soles? Surface plates are 2,3 and 4 inch thick.

I understand that the thicker the better in terms of rigidity/stifness, but how thick is enough for flattening plane soles?

I had read your info about scraping and filing. I might try that 
as well.

Ali

Ali


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## ali27 (25 Jun 2010)

Maybe if there is enough interest we can persuade
Matthew to sell them.

What do you think Matthew?

Ali


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## Lons (25 Jun 2010)

I regularly fit kitchens with granite worktops and I would be surprised if a standard 30mm thick worktop is not flat enough or rigid enough to cope with flattening the sole of a plane.
Offcuts are always available from granite suppliers locally who would be happy to cut to size and polish the stuff.

Bob


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## ali27 (25 Jun 2010)

Lons":2x74h1py said:


> I regularly fit kitchens with granite worktops and I would be surprised if a standard 30mm thick worktop is not flat enough or rigid enough to cope with flattening the sole of a plane.
> Offcuts are always available from granite suppliers locally who would be happy to cut to size and polish the stuff.
> 
> Bob



Hi Bob,

From the information I have read, kitchen granite worktops
can be less than flat up to 2mm in length. 

I don´t know how much difference that means in a 
40 inch long granite worktop.

Have you checked with a reliable straightedge?

Ali


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## Benchwayze (26 Jun 2010)

Ali...

Have a look at this, and make some enquiries of the seller. Maybe they can fix you up.

Ebay.co.uk Item No. 360267337709

HTH

John


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## ali27 (26 Jun 2010)

Benchwayze":2xko7slk said:


> Ali...
> 
> Have a look at this, and make some enquiries of the seller. Maybe they can fix you up.
> 
> ...



Hi John,

thank you for the tip. The plate is too short unfortunately.
The seller has larger ones, but they are so big and shipping
would be very expensive.

I don´t know for sure, but I think there would be interest
in a granite surface plate which measures approximately
24 inches long, about 6 inches wide and 2 inches or
so thick. If my math is correct, such a granite surface plate
would only weight 15kg! Whereas a 24 x 18 x 4 plate is 90kg heavy! Try moving that(if necessary).

The length is good, but the extra width is not needed. I doubt
you would need a 4 inch thick plate to have adequate stiffness.

Ali


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## ali27 (26 Jun 2010)

How much would a machinist charge for calibrating
a granite surface plate?

Maybe I could just buy regular granite tops(which aren´t)
really flat and have it flattened by a machinist.

Another option. Using MDF plates. They are quite flat
I think, but they lack rigidity. What if I put 3 or 4 thick MDF
plates on top of each other, would that provide sufficient
rigidity?

Ali


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## Benchwayze (26 Jun 2010)

Tufnol is also extremely flat. Not dirt cheap, but cheap enough. 

Flat enough for a plane sole, and for sharpening. Just araldite some 10mm tufnol to a 25mm thick piece of MDF and that will also be inflexible. 

HTH too.

John


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## ali27 (26 Jun 2010)

Benchwayze":3e9yu433 said:


> Tufnol is also extremely flat. Not dirt cheap, but cheap enough.
> 
> Flat enough for a plane sole, and for sharpening. Just araldite some 10mm tufnol to a 25mm thick piece of MDF and that will also be inflexible.
> 
> ...



John,

I had never heard about tufnol. This is the info I found about
how flat it is:



> Tufnol Sheet - Flatness Tolerances
> The below table is the maximum deviation from flat for Tufnol Sheet over a distance of 1000mm using a straight edge.
> Sheet Thickness Variation
> 1.6mm to 3mm up to 18mm
> ...



http://www.tufnolsheet.co.uk/tolerances.ph

Here some more info on this matter:



> Flatness test.
> If a sheet is bowed, it is tested as follows:
> 1. The sheet is laid, concave side up on a flat horizontal surface.
> 2. A lightweight straightedge 1000mm or 500 mm long is laid on the sheet in any direction
> ...





According to this source it bows very easily(am I correct?), but I don´t know what the tufnol will do if you stick it on top of MDF.

Ali


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## ali27 (26 Jun 2010)

Maybe if there is interest, we could do a group buy
for this:

http://www.axminster.co.uk/product-Axmi ... -20297.htm

And then have it sawn in 3 pieces. 24 inches long, 6 inches wide.
I don´t know how much the sawing would cost to be honest, but I
guess at least 50 pounds?

So 96 GBP(if it picked up and not shipped) for the plate,
about 50 GBP for sawing=146 GBP. Divide this by 3 and
each plate would be less than 50 GBP.

Ali


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## jasonB (26 Jun 2010)

I have just taken one of my granite kitchen worktop samples, levelled it on the carrage of my lathe and then traversed it along its 300mm length with a dial test indicator on it.

Over the 300mm length I get 0.0003" ( 0.000762mm) difference but that is a constant movement of the dial due to me not being bothered to get it totally level.

I think we can say that an off cut of kitchen worktop will be more than adequate for your needs as I said at the start of this post.

Also I would strongly advise against bonding two different materials together such as Tufnol/MDF any change in humidity will make the MDF expand/contract and your Tufnol will go concave or convex. If you must bond to MDF then glue the same material to both sides.

Jason


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## Benchwayze (26 Jun 2010)

Ok Folks...

I bow to superior knowledge on Teflon. I just hope no one tells my plane soles, water-stones and irons! Or maybe I am lucky in having stable humidity in my workshop. Can't say I ever had any problems. (Not even with rust.) 

Of course it could be that I am not an absolute perfectionist when it comes to sharpening matters. If a plane is flat, for a decent area, at the toe, around the mouth and at the heel, (i.e. those three points are in the same plane, all the way across the sole,) I am happy. Mine are generally better than that, but there's my minimum. Neither do I go to the extent of having mirror finishes on the backs of my edge tools. If they are 'satinised', and give me a reference reflection, again that suits me. 

As for performance I am happy with that too. Freehand honing on water-stones is my way. What I am fussy about is having an edge that is at 90 deg to the side of the iron, and a water-stone that is as flat as I can get it. Both of those are easy enough to attain. 

Ali,

If you are after close to zero tolerances then maybe a properly finished granite slab is the best option, that or a piece of 25mm thick float glass. Hopefully you can find suppliers for these nearer to you. I agree shipping is going to be a problem, on top of the cost. 

EDIT:
I have used the cast-table of a table saw in the past, but I don't have one any more. I suppose any cast machine table would be flat enough for a plane sole. But I could be wrong again...  

HTH 

Regards
John


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## beech1948 (26 Jun 2010)

I have just done a google search for Granite Surface Plates and come up with 30+ in the UK. You should try the same search in your country and maybe a nearby country.

I think all of this discussion about granite counters, cemetry granite etc etc is probably a waste of time as the surface accuracy of the end product is unknown and unverified.

So seek out a suitably sized proper granite surface plate and buy it 3 or 4 inches thick.

If you must cut it down then try a paving slab cutter with a diamond blade. A slightly ragged cut line will not affect surface smoothness.

regards
Alan


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## Lons (27 Jun 2010)

ali27":2hm2d49w said:


> Lons":2hm2d49w said:
> 
> 
> > I regularly fit kitchens with granite worktops and I would be surprised if a standard 30mm thick worktop is not flat enough or rigid enough to cope with flattening the sole of a plane.
> ...



Hi Ali

Just checked my own worktops with a straightedge and I would be perfectly happy to use it, (if the wife would allow  ).

If you go to a granite supplier, they will allow you to choose your offcut and check with your own straightedge before purchase. 
As well as natural granite, there are types which are reconstituted with a resin plastic and these are also worth looking at.

As far as cutting - Very easy to cut with a 4 1/2" grinder if you use and ultra thin cutting disk (1 -2mm thick). Not too much dust or too expensive in lieu of water cutting equipment.

Tufnol / teflon etc.

My background is plastics including these, and whilst their composition differs, they are both unsuitable IMO. I could show you samples of both - very bent.
Tufnol is great for components and gears as well as templates but is far from flat.

regards
Bob


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## ali27 (27 Jun 2010)

*: Lons wrote *



> Hi Ali
> Just checked my own worktops with a straightedge and I would be perfectly happy to use it, (if the wife would allow  ).
> 
> If you go to a granite supplier, they will allow you to choose your offcut and check with your own straightedge before purchase.
> As well as natural granite, there are types which are reconstituted with a resin plastic and these are also worth looking at.



Thanks again for answering Lons a couple of questions if you allow me:

1)how long was the straightedge
2)Is it a reliable straightedge
3)how much was the gap between the straightedge and the plate 

I will follow your advice to take a straightedge with me to a
granite supplier. Nothing to lose doing this and perhaps there might
be a rather flat plate available.

How much do you think it would cost to let the graite supplier
saw an offcut to specific size?

Thanks again.

Beech I did check for granite plates in my own country. Very
expensive I am afraid. 

Jason,IF I UNDERSTAND YOU CORRECTLY(which I think am not) that would mean that a granite kitchen plate is flatter than a certified granite plate which is impossible unless you got one piece that is incredibly flat by coincidence/chance.

Ali

[/b]


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## jasonB (27 Jun 2010)

I'll take a video of the dial gauge as the granite moves under it, will be later today as I'm off out soon.

As I said granite worktops are ground in the country of origin on very high spec machines and most granite suppliers in this country could not grind to such tollerance, they tend to just buff up the surface to remove any small marks that have got into the stone during transport and cutting. This is usually done with handheld Flex grinders with diamond pads.

Had this discussion with my usual granite supplier a while ago when I wanted the whole draining area at the side of a sink dropped rather than just grooves, said he could not achieve the same level of finish as the factory surface.

Jason


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## Lons (27 Jun 2010)

ali27":1s8ka3fi said:


> *: Lons wrote *
> 
> Thanks again for answering Lons a couple of questions if you allow me:
> 
> ...



A stabila 1200mm spirit level

Obviously can't certify the correctness of it but I moved the edge along the bench, turned it around etc and looked good to me.

I also have a 500 x 200 x 30 bit which I use withe abrasive and I checked that with several steel rules and showed no depressions. i haven't bothered to check with my dial gauge as I said I would be very happy with the results - doesn't mean you would! - You pays your money etc.

I could never say it is the equal of a certified granite plate, just that I would be happy with it!

Cost of cutting an offcut - depends how the guy feels but always can be negotiated.
I bought a 900 x 900 offcut of blue pearl last year for £50 for the centre of a coffee table and they polished and bevelled the edges for another tenner.

regards

Bob


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## bugbear (28 Jun 2010)

ali27":3sxgujzv said:


> According to this source it bows very easily(am I correct?), but I don´t know what the tufnol will do if you stick it on top of MDF.



It will be as flat as the MDF, which is also the case for glass layered over MDF.

Don't forget that the so-called-lapping process involves quite high forces.

BugBear


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## Lons (28 Jun 2010)

Ali

Don't take this the wrong way, but isn't it a bit OTT when the plane surface you have flattened will expand and contract naturally anyway depending of heat / cold / humidity.
And - the wood you use it on will move even more. :lol: :lol: :lol: 

Mind - if someone accused me of being OTT over my car - I would become very defensive so I'll probably be put firmly in my place over these comments :lol: :lol: 

regards

Bob


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## ali27 (28 Jun 2010)

Ok guys. I took my straightedge and went to investigate
the flattness of granite(kitchen), glass and mdf.

A 20mm piece of glass was the flattest,but I could
still see clear light. Granite(thick piece) and mdf
were both clearly not flat.

I have read much about MDF being flat, but it really
wasn´t.

I used a very good straightedge(Groz brand).

Ali


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## Mohammed Imran (23 Mar 2021)

Hi Bob,

I have 13 years of experience in surface plate lapping and polishing in India.
Do you have any idea where and how can I apply for the job?

I also worked in kitchen Granite worktop.

Thanks
Imran


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## Trainee neophyte (24 Mar 2021)

A random thought: have you considered concrete? Make your own mold using a certified (by you) flat piece of melamine or similar, and then you could get exactly the surface you want. If it isn't 100% perfect you can actually abrade it yourself. I would use 2:1 sand/cement mix, and make a wooden surround for it because it may well be brittle. I would also cure it submerged in water for at least a fortnight, but I would check for and correct any lack of straightness in the first couple of days, when it would be marginally easier to work.

No idea if this is a workable idea, but it would be cheap. Very, very cheap.


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## MikeK (24 Mar 2021)

Prior to this morning, the last post in this thread was nearly 11 years ago. Perhaps Ali has found a solution by now.


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## pe2dave (24 Mar 2021)

bugbear said:


> How confident are you of the actual flatness of the results? What have you checked against?
> 
> BugBear (with a teensy obsession in this area...)


No, not teensy, obsessional though, I'd agree. For *using* a plane, I'd suggest this is more than adequate.
Could you tell the difference between a plane bed flatted to 2 microns and .5mm?


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## D_W (24 Mar 2021)

This thread is old enough that it could bring stephen hawking back. 

If you're match planing, a #6 or #7 sized plane 2 thousandths hollow starts to cause problems. One four times that in the other direction is usable. 

It's not how accurate something is nominally, it's whether or not it works well. 

If you think that's not a problem. try match planing two fairly rigid boards with ends a hundredth or more apart. You can glue them together, but it's not good policy.

.5mm seems to me to be about 12-13 thousandths. A plane hollow in that amount would be completely unusable.


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## Inspector (24 Mar 2021)

.5mm is more like .020". A third more unusable. 

Pete


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## Jacob (24 Mar 2021)

Mohammed Imran said:


> Hi Bob,
> 
> I have 13 years of experience in surface plate lapping and polishing in India.
> Do you have any idea where and how can I apply for the job?
> ...


If you can match woodworkers needs you'd could find a market and do it yourself as a business?


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## D_W (24 Mar 2021)

Inspector said:


> .5mm is more like .020". A third more unusable.
> 
> Pete



It'd be an interesting challenge to intentionally make a plane like that and get people in a competition to try to match plane two three foot boards with it (i got converting microns and thousandths and thousandths and MMs messed up. For some reason, the answer is different!!).


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## shed9 (25 Mar 2021)

MikeK said:


> Prior to this morning, the last post in this thread was nearly 11 years ago. Perhaps Ali has found a solution by now.


Or he's now on medication for trying to surface grind a No 6 plane with half a gravestone and a broken shop window to engineering tolerances that even NASA finds redundant?

I have to question the rationale of having to have permanent access to surface plates for a small finite set of hand planes. I get it if that's something you do to each new plane you come across and you come across loads but to just finish your own hand tools is a tad OCD. Do it once on a piece of sufficiently thick float glass and Robert is very much your fathers' brother. If you really crave the tolerance get the local machine shop to surface grind it for a box of beer or bragging rights on Instagram. 

The thing is if you took two planes, one surface ground on an AA graded plate and the other lapped on a piece of float glass from the local glazier, you won't be able to measure the difference of the two on the actual material being worked, i.e. wood.


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## Bedrock22 (25 Mar 2021)

I bought a granite floor tile from the local tile warehouse, 24"x 12" some year's ago. Checked it with a Moore and Wright straight edge, all fine.
Think it cost under £20.


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## Jacob (25 Mar 2021)

shed9 said:


> Or he's now on medication for trying to surface grind a No 6 plane with half a gravestone and a broken shop window to engineering tolerances that even NASA finds redundant?
> 
> I have to question the rationale of having to have permanent access to surface plates for a small finite set of hand planes. I get it if that's something you do to each new plane you come across and you come across loads but to just finish your own hand tools is a tad OCD. Do it once on a piece of sufficiently thick float glass and Robert is very much your fathers' brother. If you really crave the tolerance get the local machine shop to surface grind it for a box of beer or bragging rights on Instagram.
> 
> The thing is if you took two planes, one surface ground on an AA graded plate and the other lapped on a piece of float glass from the local glazier, you won't be able to measure the difference of the two on the actual material being worked, i.e. wood.


I've "flattened" a few old ones but more as a clean up rather than for uber precision. 
I'd guess that 99.9% of all the precision sole flattening that goes on is a complete waste of time!
Only ever had one which was really in need of correction and that was a No7 Stanley with a definitely concave sole making edge jointing really difficult. Was new but I'd had it a few years before I realised it was the plane's fault and not my planing! Did it on my planer bed with 2 sheets of wet n dry very wet with white spirit.


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## okeydokey (25 Mar 2021)

I wonder if your local headstone maker would have a suitable sized offcut he would be willing to sell for small amount?


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## D_W (25 Mar 2021)

Jacob said:


> I've "flattened" a few old ones but more as a clean up rather than for uber precision.
> I'd guess that 99.9% of all the precision sole flattening that goes on is a complete waste of time!
> Only ever had one which was really in need of correction and that was a No7 Stanley with a definitely concave sole making edge jointing really difficult. Was new but I'd had it a few years before I realised it was the plane's fault and not my planing! Did it on my planer bed with 2 sheets of wet n dry very wet with white spirit.



Jacob, you wouldn't know. You're scrubbing beams. 

For someone doing cabinet type work, flattening a jointer and smoother is usually worthwhile unless they are slightly convex from the start (they're never dead flat, but slightly convex doesn't cause any harm). 

It takes no more than $20 of "shelf replacement" glass and $15 of PSA roll to true up every tool one will ever come across if the point is just truing the tools. A 24 inch high quality straight edge is worth buying in my opinion, but I'm sure there are people who spend 100x that in options on cars or cable TV to watch who think the straight edge is a waste of money. 

Most of the people commenting on what does or doesn't make a difference in planes would waste 100 additional hours over their lifetime planing with a junky plane that could be corrected in 20 minutes, and then bloviate about how they're not prissy. 

(let's be realistic, though - most people arguing that planes never need flattening couldn't flatten a board with them accurately in the first place, and will turn around to make up for shortcomings in a $40 plane by buying gaggles of sanders and oddball scraping tools).


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## D_W (25 Mar 2021)

Bedrock22 said:


> I bought a granite floor tile from the local tile warehouse, 24"x 12" some year's ago. Checked it with a Moore and Wright straight edge, all fine.
> Think it cost under £20.



Sounds pretty reasonable to me. The most important part of this isn't that you have a certain type of surface, but that you have a good straight edge to check it by eye. A straight edge and a light bulb is all it takes to match any boutique flatness spec. (perhaps a file sometimes if a plane is wonky in a way that's not that easy to lap out without chasing the wonkiness down in sole thickness).


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## Jacob (25 Mar 2021)

D_W said:


> Jacob, you wouldn't know. You're scrubbing beams.


 I scrubbed a beam! Once!
I discovered what a scrub plane is for.


What sort of work do you do D_W?


> For someone doing cabinet type work, flattening a jointer and smoother is usually worthwhile unless they are slightly convex from the start (they're never dead flat, but slightly convex doesn't cause any harm).


Do you do cabinet work yourself? Show us a pic or two?


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## D_W (26 Mar 2021)

Jacob said:


> I scrubbed a beam! Once! I discovered what a scrub plane is for.
> 
> 
> What sort of work do you do D_W ?



I literally posted an upper and lower cabinet made by hand and French polished in the last thread where you made dopey comments about planes, finally admitting that you do mostly coarse work and mostly with power tools the last three or four decades.

Entirely solid wood with hand beaded flat panel doors, cut mouldings top bottom and middle and colored with micronized earth pigments.

I've planed more board feet of wood in the last five years than you did your whole career, and not pine.


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## Orraloon (26 Mar 2021)

The other and free option is the cast iron top of your tablesaw. Provided its reasonably flat. Check with a strait edge first. Saves having to lug around and store a huge lump of rock and doing yourself a mischief. It's how I did my planes.
Regards
John


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## Jacob (26 Mar 2021)

Orraloon said:


> The other and free option is the cast iron top of your tablesaw. Provided its reasonably flat. Check with a strait edge first. Saves having to lug around and store a huge lump of rock and doing yourself a mischief. It's how I did my planes.
> Regards
> John


Yep. It's what I've been doing for years. And I use thin paper backed wet n dry, very wet. Nothing is flatter for grinding/polishing, in terms of an ordinary non engineering workshop.
I've also used the toughened glass door saved from a cupboard, which works perfectly well.
Well it would do wouldn't it.
You get drawn in to doing all these pointless things by the enthusiasts, I even bought eze lap diamond plates which was reckless as they are expensive and have low resale value. They don't cut any better than various Norton stones and I have the feeling they won't last as long. I do use them however as they are convenient and I want to get my moneys worth! The coarse side of a Norton combi "0" cuts a lot faster than the coarse diamond Eze Lap.
I've never been tempted by water stones as they sound so inconvenient and messy, judging by all the descriptions you get on forums. Nor a "Tormek" which is universally described as "very slow" which I interpret as "very pointless".


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## Jacob (26 Mar 2021)

D_W said:


> I literally posted an upper and lower cabinet made by hand and French polished in the last thread where you made dopey comments about planes, finally admitting that you do mostly coarse work and mostly with power tools the last three or four decades.
> 
> Entirely solid wood with hand beaded flat panel doors, cut mouldings top bottom and middle and colored with micronized earth pigments.
> 
> I've planed more board feet of wood in the last five years than you did your whole career, and not pine.


Couldn't find it - do you have a link? 
Do you micronize your own pigments?


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## Phil Pascoe (26 Mar 2021)

okeydokey said:


> I wonder if your local headstone maker would have a suitable sized offcut he would be willing to sell for small amount?


I expect his local headstone maker imports them ready made from China. I had an acquaintance who owned a granite quarry - he could but them them from China cheaper than he could get the granite out of the ground.


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## Phil Pascoe (26 Mar 2021)

Jacob said:


> Only ever had one which was really in need of correction and that was a No7 Stanley with a definitely concave sole making edge jointing really difficult. Was new but I'd had it a few years before I realised it was the plane's fault and not my planing!



I bought a new Stanley No.7 about 30 years ago and sold it on it was so bad. I have an old (red) Marples No5 that was winding so badly I put it on a coarse alox disc on my lathe. It's fine.


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## D_W (26 Mar 2021)

Jacob said:


> Couldn't find it - do you have a link?
> Do you micronize your own pigments?



Robin artist colors and Kremer for earth pigments. Go look for the pictures yourself. Until you post something that would suggest you could use planes for fine set work, i have no intention of mapping my posts for you.

You give people terrible advice unless they want to make large blocky test pieces. There are actually people who do neat work and who would gain from better advice instead of being told to forgo 20 minutes of work on an old plane.


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## Jacob (26 Mar 2021)

D_W said:


> Robin artist colors and Kremer for earth pigments. Go look for the pictures yourself. Until you post something that would suggest you could use planes for fine set work, i have no intention of mapping my posts for you.
> 
> You give people terrible advice unless they want to make large blocky test pieces. There are actually people who do neat work and who would gain from better advice instead of being told to forgo 20 minutes of work on an old plane.


OK I found it! If you're working on something mostly hand tools....updated
Not bad.
Design a bit crude - it's always a good idea to copy a good example rather than trying to work it out for yourself for the first time - design is always first priority however good/bad the workmanship.
Colours and finish a bit blotchy - possibly over ambitious?
Well done!
PS - horrible hinges!! Surprised to see all those electrical devices kicking about on the floor - they'll be the apprentice's I imagine?


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## D_W (26 Mar 2021)

Design constrained by Mrs demands to fit between mantle and wall. Let's see something you did by hand last year. I saw your fence post test cut demo and thought it was a ruse. My tool work is literally everywhere on these forums, too, and I've never had someone get a plane back from me and suggest it wasn't better. 

You literally bloviate about endless nonsense that you're not qualified to offer an opinion on and get upset if someone actually knows enough to say whether or not something makes a difference in plane setup. Your response is test pieces and pine. You don't even recognize what you don't know.


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## Jacob (26 Mar 2021)

Seeing as you asked:
I'm retired now and messing about doing all sorts of things. My last big job was 10 of these windows and this staircase. Midwinter sunrise.
The windows were beyond repair so I made replicas. At 14' tall required a lot of hand planing. I've always done a mixture of machine/hand-work as necessary - with a bias towards hand work where it's viable.
The staircase - and another similar one, had a lot of 4" square newel posts also reaching 14' so these too needed a lot of hand planing (2 sides square by hand, the other 2 through the thicknesser.)
I've also done lots of odds and ends of furniture but most of what I did was architectural.
Biggest single job ever was a huge set of sashes and doors for a big house in west of Ireland, meticulous copies of 1812 originals. Needed three excursions through the year and a little team of us camping on site. Did a bit of tourism too - Matt Molloy's bar in Westport, Croagh Patrick, a few nights in Dublin etc
I've nearly always done replica work with occasional repair/renovation, which entails an incredibly valuable learning curve as you are looking at minute details , down to tool marks, pencil marks, over the shoulders of those did the work first time around. You see their mistakes too!


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## D_W (26 Mar 2021)

Jacob, that's coarse work that you're showing with near nothing planed. No wonder you don't have a clue. Note that I called my case utility furniture (it was, i had to copy the proportions from another case exactly and the mrs. wanted soft close hinges which I have a distaste for, but the cabinet is used by the kids and that's that. No face frame, no center post - broke all of my personal rules. I made it, anyway, and hid in the chance to try things while making it - the other choice was to have my mrs. try to find someone like you to create some horrid overpriced piece screwed together (at least that one is properly joined). 

You have windows and coarse work. There's nothing there notable in terms of hand tool or planing work. All of the railings look like assembled parts from a lumber store. Let's be realistic about what that stair work is, it's crude.

Let's see the part where you planed, resawed, created sliding dovetails, etc. It's always missing.

you have an opinion about planes all the time, but you never show any tidy work done with them. Maybe everyone doesn't want to assemble sticks.

The last point about this, as I've taken interest in actually using planes, this is my hobby. There should be no part in this re: planing that you have a better sense of, but it's backwards. You post work where the planing is missing, and while there are plenty of folks on here who post wonderful hand work, you never do. Your opinions about how good of condition planes need to be in are always backed up by the work you show.


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## D_W (26 Mar 2021)

by the way, if someone had a window question, I'd send them to you or to someone I know here who makes one off casement bits. where you fall off the wagon is that you don't have a good grasp on planes or what they're actually capable of or what makes them work well, just as you don't know enough to know when to stop when it comes to abrasives. You've had to do little with it, it's apparent (the abrasive side), and you have no means of testing after the fact, anyway. So you choose a slower way to do things than my suggestions, but you can't stop yourself, and then one that is less accurate, but you can't stop yourself from opining that it is. When we see your work, we know then why you have no idea. 

I can only lead people in the right direction with planes. I wouldn't bother to comment on windows, but I know that I know little about them. Of course I could do peripheral work on them, but it wouldn't be enough to get me to give advice to other people. That's where you really are with planing and sawing.


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## Jacob (26 Mar 2021)

Talking of Ireland I've just bought this very beautiful book. Highly recommend! Irish Country Furniture and Furnishings 1700-2000
The link includes a vid


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## segovia (26 Mar 2021)

I picked up some granite worktop offcuts from a Kitchen fitter, I was surprised when I ran a straight edge over it that it wasn't flat. Over 30" it was 0.005" out


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## D_W (26 Mar 2021)

There's no shortage of fine furniture in the older areas of the united states if one wants to make fine furniture. I generally make tools. I count 16 pieces of case work or cabinetry in my house that I've made, and a laddered bed. And 8 guitars (and probably more than 100 tools). That's enough for me for the furniture, though the jones to make things out of wood will probably change that. 

The difference between you and me is I'll make something like this in a style that I don't really love, and squeeze out of it what I can. If someone asks me how to dimension the wood by hand, i can tell them precisely how to learn to do it. You will show a pine test piece. 

If someone wants to ditch their bandsaw but still saw wide panels or guitar tops. 





I can tell them exactly how to do it, and I can tell them how to make the saw out of shim stock and wood. You'll show a test cut with an old hand saw in a way that would get anyone to think it's too hard to do. 

I'll show a case in process (even though it's not my favorite thing to make) joined top and bottom with dovetails and dovetailed shelves with hand planed T&G back installed later, and mouldings and base made entirely by hand (there was very little on this case that wasn't done by hand. I got in a rush on the top half and did skip about 20% of the wood through a thickness planer, I can't remember why - I probably wouldn't do it again as much of the other stuff that I've made is 100% solid from rough lumber with no power tools at all). 



I've got pictures of the remnants of doing the work:




You talk about planes and show windows. 

You haven't got the actual experience doing anything that you talk about. And I'm just a hobbyist. It should tell you something. If I thought you had a chance of having had enough detail go through your nerves to know the difference, I wouldn't be so rough on your suggestions, but you give terrible advice. That's all there is to it. Your advice leaves people thinking that closer work will be difficult to do, or that this stuff isn't easy by hand. If the planes are set and prepared properly, it's just exercise no matter what any reasonable wood or level of figure is. The resawing, just exercise. But with shoddy tools and ignorance of how they work, it could seem quite difficult.


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## D_W (26 Mar 2021)

segovia said:


> I picked up some granite worktop offcuts from a Kitchen fitter, I was surprised when I ran a straight edge over it that it wasn't flat. Over 30" it was 0.005" out



Most of it probably isn't flat. If it's hollow that amount, you could probably get away with using it. When I built my bench, I spent about 15 minutes making sure that the area that my glass lap runs on had no visible light to a starrett edge. It's 15 minutes worth spending. The rest of the bench is flat, but not as intentionally flat. If you're making guitars or something of the sort, having an area that flat on the bench as a reference is a significant time saver. 

The reason I mentioned above about the straight edge being useful is that sometimes you can get something really cheap and it _is _flat, but marginal straight edges won't know the difference. 

I'll wait for jacob to mention that such things never matter, but anyone who has ever set up or built a guitar with frets 5 thousandths high in an area (especially if it's just a couple) will know how important it is to have a straight reference for flatness.


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## Jacob (26 Mar 2021)

segovia said:


> I picked up some granite worktop offcuts from a Kitchen fitter, I was surprised when I ran a straight edge over it that it wasn't flat. Over 30" it was 0.005" out


Strewth - that's about the thickness of a human hair! Was the straight edge straight?


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## cowtown_eric (27 May 2022)

I'm well aware of the"flat sole society" and can see the benifets. Don't want to argue the point at all, just want to know if anyone knows any proponent of "sole flatness" has actually measured the flatness proported to any degree (.0001 or finer) or just been satisfied with putting a straight-edge over it???

Eric in the colonies


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## Ttrees (27 May 2022)

cowtown_eric said:


> I'm well aware of the"flat sole society" and can see the benifets. Don't want to argue the point at all, just want to know if anyone knows any proponent of "sole flatness" has actually measured the flatness proported to any degree (.0001 or finer) or just been satisfied with putting a straight-edge over it???
> 
> Eric in the colonies


Like this?
("timestamped" at the feelers)


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## cowtown_eric (29 May 2022)

Ja like that, but .03mm equates to .0018", and I'm hoping to find someone whom has measured the "flat sole" down to .0001", an order of magnitude finer.

Please don't tell me it makes no difference, I know it doesn't-unless you got a "plane 0 shame", but what I want to investigate is a measurable effect of using an 8" deburring wheel on a flat sole. Some folks tell me it will create gouges, but I'm of the opinion it has less than .0001" difference.


I could absolutely put it on a surface plate, and try to put a feeler gauge under it ?ever tried to find a .0001 feeler gauge- but even that wouldn't tell me anything other than it won't fit under the outside edge, but anyone whom has flattened pane soles will show you how the deviations oft appear away from the outside, so the feeler gauge concept tells me nothing other than the outside edge is tight to a surface gauge.

Veritas block plane





Veritas Tools - Block Planes - DX60 Block Plane


DX60 Block Plane from Veritas Tools



www.veritastools.ca




is proprted to be to within .0015 but it's a short sucker...

It is a total rabbet hole, and maybe a "folly", but I'm going there, maybe without success... who knows

Eric


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## Ttrees (29 May 2022)

Jack Forsberg had a plane scraped for him, he's pretty happy with it.
I've heard it said it creates extra effort, as to how much convexity one has,
i.e a plane like in Cosman's videos which is noticeably concave along the length
as is audible, and is said to be more consumptive of the wax, since the front will be scraping it off somewhat more.
Obviously preferable to something the opposite, and wouldn't take but a few licks on some new abrasive.

An interesting experiment to do, I haven't went there myself as material deflection is an issue on such a skinny bench top, but I hope to get at the proper bench someday, and am leaving off the tiniest bit of lapping of the no.8 I have for the job, as that is the tool IMO which will highlight this the most.

I would be eager to see what folks preference is where the plane will hinge from,
and if that differs on various sized planes.
It might be a more inclusive question, for the folks who don't have a guaranteed surface plate and all the rest.

Cheers
Tom


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## Ttrees (29 May 2022)

More so into this realm of the question maybe asked
Is there a trade off for that efficiency should want even less variables.

I've read of a few disliking the LN planes due to their weight,
but drag is less written about, and hard to know if a bit of that maybe part of this.
Although there is or was a college in UK which fettles even those.

Hard to find these answers, since many seem to plane in very variable circumstances.
I use my bench as one would check something on a surface plate, as I see it as more of a 
certainty laminating and plugging expensive reclaimed timbers.
Everything else just looks odd, difficult, time consuming and wasteful to me.

Seemingly a big difference from someone who works traditionally, and doesn't have a polished bench which is easy to clean with one or two swipes from a bearer with no chips for detritus to stick into.

One could speculate this is why Roubo made them benches so thick, as the argument of convex vs concave bench & plane hinging debate was the sharpening debate of today,
but then again maybe discounted as the design is spoiled by those pesky through dovetails.


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## pgrbff (29 May 2022)

It seems to me that it is all a matter of individual preference. I'm not sure telling someone new to the hobby that flatness or sharpness or waterstones aren't necessary is very useful. Surely they need to be offered the full picture and be left to choose for themselves.
Could this be achieved with an old dished oilstone? I doubt it. Does everyone want to achieve this level? I doubt it. 
Personally, I am just interested to know what can be achieved if you want to.


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## Jacob (29 May 2022)

Ttrees said:


> ......
> 
> One could speculate this is why Roubo made them benches so thick,


No need to speculate - the mass resists movement better when bashing away with hand tools. There is no other reason. Everybody does it, not just Roubo.


Ttrees said:


> as the argument of convex vs concave bench & plane hinging debate was the sharpening debate of today,


Never heard of bench/plane "hinging".  Or "hingeing" for that matter. I guess it's just another silly idea you might encounter if you go down the modern sharpening rabbit hole!


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## Ttrees (29 May 2022)

Jacob said:


> No need to speculate - the mass resists movement better when bashing away with hand tools. There is no other reason. Everybody does it, not just Roubo.
> 
> Never heard of bench/plane "hinging".  Or "hingeing" for that matter. I guess it's just another silly idea you might encounter if you go down the modern sharpening rabbit hole!


Only kidding about the Roubo bench, but the point of a thick bench and all that, is what I was making.
That's not to say that how flat a plane is (how much bias a convex surface has.)
wouldn't be noticeable in other ways, 
Match planing,
planing to remove ripples on a really dialed in machine, or however snipe maybe dealt with,
and likely a whole lot of other ways of consistent things which might make ones mind up about this.

Hinging, or call it pivoting if you like.
Its a term used for checking how flat something is.
Common stuff really, nothing new about it.
Should be in one of those old books you've read.

Tom


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## Jacob (29 May 2022)

Ttrees said:


> ....
> 
> Hinging, or call it pivoting if you like.
> Its a term used for checking how flat something is.


I check stuff by looking at it. Or looking at winding sticks.


Ttrees said:


> Common stuff really, nothing new about it.
> Should be in one of those old books you've read.


Nope - news to me! Sounds like something from one of the newer books, or youtube!


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## Ttrees (29 May 2022)

@Jacob 
I'd be quite surprised the book you sold didn't mention this?








Sold - David Charlesworth "Furniture Making Techniques"


David Charlesworth's Furniture Making Techniques. Good condition. "A selection of the best from Furniture & Cabinet making magazine" £20 inc P+P




www.ukworkshop.co.uk


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## TFrench (29 May 2022)

I think the hinging thing is a crossover from engineering practice. When hand scraping components, checking where they "hinge" on a surface plate can reveal high spots. Personally I think its mildly OTT for a hand plane...


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## Ttrees (30 May 2022)

One of the best ways to get an idea of flatness without needing a guaranteed plate, or straight edge and feelers,
provided some sort of surfaces are available, i.e checking against cast iron tables or whathaveyou.
The method does what it says on the tin, and is a basis for flattening something, whether it be precision or rough like belting a rusty metal plate with a big hammer.


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## Jacob (30 May 2022)

Ttrees said:


> @Jacob
> I'd be quite surprised the book you sold didn't mention this?
> 
> 
> ...


There you go - as i said, one of the new books!


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## Jacob (30 May 2022)

Ttrees said:


> One of the best ways to get an idea of flatness without needing a guaranteed plate, or straight edge and feelers,
> provided some sort of surfaces are available, i.e checking against cast iron tables or whathaveyou.
> The method does what it says on the tin, and is a basis for flattening something, whether it be precision or rough like belting a rusty metal plate with a big hammer.


Nobody needs "a guaranteed plate". 
Straight edges occasionally useful but not essential. Edge of a combi square is useful for checking for flatness.
Feeler gauges no use to woodworkers. 
Straightness is assessed by "looking" at the thing. Twist with winding sticks.


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## Ttrees (30 May 2022)

Agreed Jacob, nobody needs such a plate, if they have the ability to make something quite flat for themselves.
I have feelers, but only bought them to make my own surface plate.
It's quite evident with pivoting/hinging, tapping, and using ones eyes with good lighting, to get close, and such methods can be utilized the whole way through to unmeasurable standards for the non machinist, who doesn't have such equipment.

For planes and things, one could argue that the lapping on abrasive is more foolproof than using a deburring wheel alone, or other method of "targeted removal" (where-ever @D_W is?)
as a high spot is obviously going to have more contact,
and the material from the centre can be removed more evenly, leaving it a simple matter of
erasing however much material one leaves on the edges
i.e how much one feathers the ink off the edge, or infact occasionally runs off the abrasive
if using a smaller area of contacted surface than the item (plane) is.

(the edges being the reference as anything the opposite is pretty much unmeasurable)
i.e if one feels the need to do the test like Cosman shows beforehand,
because after say 10 few swipes on a large abrasive would throw whatever feelers
(one thou shim stock in Cosman's case) one would be getting beyond an "Prussian blue" test if one has a permanent marker around.

One can see most of the edge disappear with one or two short strokes of the larger area,
as abrasion will favour the edges and eliminate the witness marks one has been careful to keep an eye on.


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## Jacob (30 May 2022)

Ttrees said:


> Agreed Jacob, nobody needs such a plate, if they have the ability to make something quite flat for themselves.
> I have feelers, but only bought them to make my own surface plate.
> It's quite evident with pivoting/hinging, tapping, and using ones eyes with good lighting, to get close, and such methods can be utilized the whole way through to unmeasurable standards for the non machinist, who doesn't have such equipment.
> 
> ...


It's called "over-thinking". Elaborate solutions to an imaginary problem.


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## Ttrees (30 May 2022)

Toolmaking is what it is.


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## Ttrees (30 May 2022)

...and that is why the tolerance of those planes in the Cosman video is there,
i.e specifically biased so one can lap them on float glass or some such thing with a
wide and long strip of paper, and end up with whatever tolerance they wish,
should they feel the need to even work it atall.
Cosman shows these right off the bat and still does his trademark thing pinching shavings.

It's inbetween this and the smallest fraction of convexity which is likely for most, unnoticeable for all who don't have such want for finer tolerances,
It makes an interesting topic to me, but said hard to get an answer .
I'd like to see what Rob would make of it, should he wish to give that wide plank planing video
another go and demonstrate everything he knows, not just hints of such working.
Maybe he still makes a good few quid from the old video?

Point being he has a stout bench suitable for the job, and thus able to have a true reference and ability to note what one shaving will achieve,
not that one needs a plane of this tolerance, I've dimensioned some timbers with a scraper plane, before I knew how to use the cap iron,
it's all about speed and surety for fine tolerance things which have no room for error,
and I haven't been/yet to be swayed by anyone's opinion of how much of a tolerance or indeed how much convexity one has made their longer plane(s) who thinks works different than what I find suitable, (i.e duplicating the surface of the bench which Cosman does suggest but that might not have come across for some folks)


But yet there maybe a lot more ways this might be noticeable, which I'm not even properly given credit to, as is always the case with woodworking...
Take flipping the work around... for making up a wide panel, seat, guitar or whathaveyou, can one achieve the same gapless result without excess hollowing, so one can change their minds without without a load of faff re-matching what could be a multitude of timbers
(laminated or edge joined bench or table tops comes to mind) 
say one plank got some damage at a later date than anticipated.

This I'd guess would be up there for the most noticeable of all reasons to want a bias,



Tom


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## ivan (30 May 2022)

What's a perfectly flat plane sole for, if you could scrape it so? 
Take a final shaving from a flat board; the No.7 is running on a narrow part of the sole just in front of the mouth, and the heel right at the back. However, once running on the board, all downward pressure is at the tote. This can flex the sole downward. If the sole is very slightly hollow it still flexes down to the timber surface. If too convex, the plane might not cut. So provided the sole is either flat or slightly hollow over the full length, perfect flatness is not required as the sole is not perfectly rigid! Less true with shorter planes, but then these are not required to produce critical flatness as for edge jointing, say.
Picked up a calibrated chinese granite plate from Axminster about 450x600x100 V-V-heavy! Took 2 to put it in my van. Bought for metalwork some years back. For non critical use I found some granite place mats in Aldi/Lidl, glossy surface appeared V flat checked by using it as a mirror. Plenty good enough for abrasive backing.


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## Inspector (30 May 2022)

Granite and cast iron surface plates are for measurement. Not lapping tools on sandpaper! If you did that where I worked you would get roasted. Lap on something else and check with the surface plate. Bunch of barbarians and heathens.  

Pete


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