Fastest way to flatten chisesl I've found

[Anonymous]

Over the years, I've tried loads of ways, scary-sharp (Wet ' n' Dry), oil stones, water stones, DMT stones, powered flat platten machine.

The powered one was easiest and the course DMT quickest

Until now


I had an order with Axminster that was below minimum for free postage, so chucked one in to get to over £45

First attempt yesterday and I am over the moon!! Not only does it flatten MUCH faster than any of the other methods I have tried, it is actually more accurate with the whole of my chisel dead flat in a couple of minutes.

The only caveat is that despite the claims, the chisel does not get polished to a mirror - not sure that I care about this one jot though as the important thing is flatness (finer scratches do mean better edge). However, I ran it over my Norton stone for 20 seconds and now it is flat and has a mirror surface.


Worth every penny

http://www.axminster.co.uk/product-Harima-Lapping-Kit-20855.htm

 

[woodbloke]

Tony - as you know, I was recently playing around with this sort of thing and was using 6mm float glass with various grades of silicon carbide w/d paper glued on. I had good results with this method and it was fairly quick to do. What worries me with the lapping plate is that after some time the carborundum paste may wear the plate into a hollow which is undesirable for flattening the backs of chisel and plane blades. With the scary sharp method the plate material is never touched so when the paper ceases to cut it's just replaced with a new bit, or replaced with a finer grade - Rob

 

[NeilO]

Funnily enough Tony I did exactly the same as you, adding it to get the free delivery (tightass B*****ds we are, or what :lol: )
the grit range was a little disappointing being more aimed at grinding rather than lapping (or at least as I would describe lapping ie , the finishing of a tooled edge)
grit sizes were 90, 120, 150, 180 and 240 in mine , same as yours Tony??
would have prefered something like 150, 180, 240, 400, 600..
but the price isnt bad ,as is the lapping package in itself, works well for what is is, even if the grit sizing is a little bit on the coarse side..
but for £15.00 ish you cant really go wrong , and added to some descent diamond stones you would pretty much have everything you need..

Rob, I think the plate is pretty much indistructable,as the muppet I am , whist hanging a 20 oz hammer missed the hook , and crash , you guessed it dropped slap bang square on my new lapping plate, you can guess the air went a little blue , and cursed myself for being such a tw*t.... but checked the plate for flatness and was perfect even after its trauma, so all in all, I think it may take some lapping before its truley fubar.. :lol: , although I would guess i will need replacing sometime in my 60`s.. :shock:

having had a second look , the grit sizes are 90, 120, 180, 240 and 400...

 

[woodbloke]

I suppose it all depends on just how hard the surface of the plate is. If it's been case hardened, in which event it's just about as hard as it's going to get then I would think it would be OK...t'would be interesting to see just how it wears over a period of time with reasonable use. Cost wise, £15 sounds good, scary sharp is cheaper, 'specially if you buy's your w/d grits of Salisbury market ...piece of glass cost me about £1 iIrc - Rob

 

[NeilO]

Rob, using "your" glass and w/d method could I flatten my plane soles on it...I take it I would need a peice of glass at least a couple of ft in length?

Stanleys No3, 4, 41/2, 5, 51/2, and 6....Oops, I think I have finally hit THAT slope. :lol: :lol:

 

[Joe]

In the interests of preserving the plate surface, might it be an idea to use some self-adhesive plastic, like the stuff that comes with the Veritas stone pond?

 

[Anonymous]

What worries me with the lapping plate is that after some time the carborundum paste may wear the plate into a hollow which is undesirable for flattening the backs of chisel and plane blades.

Absolutely Rob. This did concern me, however, the plate is prepared on both sides and quite long. Unless one has an awful lot of chisles and plane irons to flatten I don't see it as a problem - one only flattens them once after all and the total cost of £14 is not particulalry high


I think the palte is hardeend (it has a sticker claiming it is made in japapn and they are welll known for producing hard steels, and the surface is prepared ready to hold the grit in place)

 

[Anonymous]

grit sizes were 90, 120, 150, 180 and 240 in mine , same as yours Tony??

Same as yours Neil, but with 400 grit as well - still does not 'polish' the back, but I am chuffed to bits with the system

 

[woodbloke]

Rob, using "your" glass and w/d method could I flatten my plane soles on it...I take it I would need a peice of glass at least a couple of ft in length?

Stanleys No3, 4, 41/2, 5, 51/2, and 6....Oops, I think I have finally hit THAT slope. :lol: :lol:

Neil - this is a jig I made recently that works on the 'scary sharp' principle

to lap plane soles. It's 1000mm long and the glass is 10mm float glass, the idea being that you can trap sandpaper (aluminium oxide off a roll) under the two side pieces so that it stays flat and doesn't ruck up. This is a pretty big jig and was quite expensive to make, but if you were to shorten down a fraction and use 6mm float glass instead of 10 it would work just as well...I used 10mm just because it was over such a big distance but I made an earlier one which was shorter using 6mm glass - Rob

 

[NeilO]

Cheers for that, Rob..
looking at your pic I`m guessing the glass is about 6" (150mm) wide with a "runway" of 4" (100mm) , would that be about right for planes??

 

[woodbloke]

Yup - that's about it. Depending on the width of paper in use I trap roughly about 10-12mm under each side piece. I can't take credit for this jug as I saw it at the last Axminster show where it was being used to lap the soles of student planes from a college in Bucks if memory serves...I thought it was such a good idea that I went home and made one, one of the best things I saw at the show that day - Rob

 

[bugbear]

What worries me with the lapping plate is that after some time the carborundum paste may wear the plate into a hollow which is undesirable for flattening the backs of chisel and plane blades.

Absolutely Rob. This did concern me, however, the plate is prepared on both sides and quite long. Unless one has an awful lot of chisles and plane irons to flatten I don't see it as a problem - one only flattens them once after all and the total cost of £14 is not particulalry high


I think the palte is hardeend (it has a sticker claiming it is made in japapn and they are welll known for producing hard steels, and the surface is prepared ready to hold the grit in place)

Don't forget, in true lapping (as opposed to what some woodworker's do to flatten plane soles) it's the HARDER material that wears away.

BugBear

 

[bugbear]

Yup - that's about it. Depending on the width of paper in use I trap roughly about 10-12mm under each side piece. I can't take credit for this jug as I saw it at the last Axminster show where it was being used to lap the soles of student planes from a college in Bucks if memory serves...I thought it was such a good idea that I went home and made one, one of the best things I saw at the show that day - Rob

I saw that, and thought it awful. It's almost a worst case for generating convexity, as opposed to either "lapping" properly (see recent links to S&S) or printing and cutting using a reference surface, per my website.

BugBear

 

[Philly]

Gents
i have one of these and have been experimenting with it. The coarse grits break down REAL fast -might look into the coarse diamond pastes instead.

A thought on the lapping plate wearing - the plate is not hardened ( i used a file to remove a damaged edge) Isn't there some engineering principle with two metals rubbing against each other and the softer surface not wearing? Sorry - not my strong point but I'm sure I read that somewhere :roll:
Cheers
Philly

 

[woodbloke]

The jig I made does work well, I've not had a plane go convex yet using this method - Rob

 

[tnimble]

Nice lookin Jig Woodbloke.

As per two surfaces the softer srface will wear the least as the very hard grot partials will be pushed into the surface of the softest surface. Therefore the particals do not rub anymore against that surface.

 

[tnimble]

I saw that, and thought it awful. It's almost a worst case for generating convexity, as opposed to either "lapping" properly (see recent links to S&S) or printing and cutting using a reference surface, per my website.

I use an similar but less pretty ramp. However I have mine not dead flat but slightly concave (0.2mm over a length of 1.2 meter) This produces a near dead flat very slightly concave sole. Besides using the ramp I also mark and attack the surfaces with various files and scrapers.

This weekend I did a no 5C took about between 15 and 20 minutes to flatten sole and square the sides. The sole was already pretty flat, but the sides where off by around 0.8 and 0.5 mm.

I find using loose grit partials too messy. I recently began using alcohol/ethanol as a lubricant and to prevent glazing

 

[Chris Knight]

Isn't there some engineering principle with two metals rubbing against each other and the softer surface not wearing? Sorry - not my strong point but I'm sure I read that somewhere :roll:
Cheers
Philly

I am not sure how general it is but I was always warned not to run alloy gears with with steel ones as the latter would wear quickly. I think the idea is that particles of the harder material become embedded in the softer and these prevent it from wearing whilst at the sme time wearing away the harder.

 

[TrimTheKing]

the idea being that you can trap sandpaper (aluminium oxide off a roll) under the two side pieces so that it stays flat and doesn't ruck up.

Hi Rob

What paper do you use on this (and where do you buy)? I am in the process of buiding something very similar myself and can only find 240grit on screwfix and machinemart. I would think I need something a bit finer too once I get close to flat?!?

Cheers

Mark

 

[ike]

A thought on the lapping plate wearing - the plate is not hardened ( i used a file to remove a damaged edge) Isn't there some engineering principle with two metals rubbing against each other and the softer surface not wearing?

Absolutely - ever noticed how an engine crank journal wears more than the bearing shell. Because the abrading particles get embedded in the softer metal and stay there.