St James' Bay Tool Company infill plane kit

[gasman]

There will be a slight pause in this project as (a) I have to lay paving slabs outside my workshop and (b) the brass lever cap screw supplied with the St James Bay kit is awful - it has a steel threaded rod inserted into the brass knob and is ugly so I am going to make my own. I have ordered some brass rod and acme tap and die and will wait until they get here. Oh just thought I need a knurling tool too - it all adds up but this is all 'for the future' as I keep telling myself. Any advice as to what sort of knurling tool to get to use with my Sieg C3 mini lathe?
Cheers all and thanks for any advice
Mark

 

[rxh]

I think that the two wheel style of knurling tool is best because it does not put a high load on the bearings of the lathe.

 

[gasman]

thanks you I had kind of thought that I remembered that from one of Jimi's infill threads. I have my eye on one on eBay so hopefully won't be too much
Cheers Mark

 

[-Matt-]

Thanks so much for the comments
My wife came down during the peining and told me off for making such a lot of noise.

Give her some ear defenders. Or I dunno, get a new wife

I'm watching this thread with interest, whilst also really wanting to make my own. Liking the progress and I'm interested to see your results from turning a new screw. I'm toying with the idea of getting a mini lathe (my current one is... well... bodged in places and far from smooth running)

 

[gasman]

It is a bit stop and start this project but some progress made over the weekend.
I think I had shown you the cap iron which was supplied just as a casting

I think I have also mentioned the lever cap screw was awful - an M8 steel threaded rod secured into a rather inferior looking piece of brass, so I decided to replace the screw with a 7/16-10 acme threaded version. I bought an appropriate tap and die from rdgtools which arrived friday
I started by marking by eye the centre of where the cap screw will be as shown and drilled out an 8.5mm hole which is the closet I had to the 8.7mm I had calculated from various online formulae (OD in inches - pitch/10 +0.005) then converted to mm or something like that

Then I tapped that 8.5mm hole using the 7/16 acme tap - easy as anything using generous amounts of cutting fluid

Then I made the sides parallel by milling the edges. The internal width of the plane is 63.3mm so I made the lever cap 62.8mm wide

Then it was just a case of filing the body of the lever cap down, bit by bit using decreasing grades of file and drinking a lot of tea. I actually switched to Abranet 120, 180, 240 and 320 as this seemed to be an easier way of doing the smoothing. Then I used my recently acquired metal polishing wheels on a bench grinder with waxes that I had bought from metalpolishingsupplies.co.uk http://www.metalpolishingsupplies.c...aluminium-brass-steel-stainless-steel-11pc-8/ - OMG the transformation. In literally no time I went from that very rough looking casting to this

I cannot cut the lever cap screw yet as I need a holder (handle) 33mm in diameter for the die
So I started thinking about the inflll
Purists need to look away now as I have been doing an experiment for the last few days in the rapid drying of timber on an oven
We cut down a rather sweet little weeping beech tree recently - the top of which had the most figured beech I have ever seen. I know it is only beech but even so I thought it would make for interesting infills and also a memory of this tree which was small and right in way of SWIMBO's view down the garden (we planted 4 other trees the same day I cut it down to offset our guilt). So I cut it up, placed it on the Aga and have been drying them it all week. It is now down to 8% or less I think, and the weight loss each day has dramatically fallen

I chose this piece for the front bun which I thought would be by far the easiest piece to make (and therefore abandon if it is no good)

So hare is the rough cut front bun awaiting some serious shaping and fitting

I have my eye on this piece for the rear infill, which, shakes aside, has a beautiful curve to do the curved handle bit. We will see

More soon!
Thanks for looking
Mark

 

[rxh]

Very nice work on that lever cap.
I hope the "wood cooking" works out OK - I've never tried anything like that.

 

[n0legs]

Lovely job on that lever cap. The Beech has found a worthy use, excellent =D>

I hope the "wood cooking" works out OK - I've never tried anything like that.

My girls brought home some bits of wood last year that the tree cutters let them have, it turned out to be sycamore.
By the time I had cut it into some useful shapes a sizes I found that it fit in the halogen oven :-$ So while the good lady was out I played :lol:
I got it down to 8-9% in about an hour.

 

[gasman]

What I have definitely found is that after a night on the oven top, the wood feels very dry and hardly registers on the moisture meter at 6% or so. However after a few hours away from the oven the moisture content has crept up again - i.e. there is moisture in the deeper layers which takes a bit longer to come out. The weight kept coming off for more than a week but is now down to a gram a day or less for a piece weighing 1kg - I think we are virtually there!
I am going to finish the front bun completely and polish it up to see what it looks like before committing on the rear infill.
Thanks for interest
Mark

 

[gasman]

I think my experiment with rapid drying of chunks of timber has failed
Having done a 'dry run' of a piece of the figured beech which had far too many cracks to be the final front bun

I started cutting down to size the final piece for the front bun, using a bandsaw, 12" sander, plane and a router to take the sides off
After I got to this stage (i.e. with new wood exposed, I put my moisture meter on the base and found to my disappointment that it was registering 18%. So my week of baking on an Aga was not as successful as I feared

The following day, after another night on the Aga, it had shrunk and was no longer a snug fit. Bummer.
So I need to think carefully about whether to wait a good while for the beech to dry or to use something else. I have lots of very dry mahogany etc so I think it will be that
I am hoping to get the lever cap screw finished this week
Cheers Mark

 

[Biliphuster]

Fick's laws of diffusion are a pain aren't they? If you graph weight and surface moisture content and keep a note of the starting values you can make sure that your wood is fully dry but I appreciate this a bit of a rigmarole. I find six weeks in the airing cupboard is usually equal to about a year air drying.

Having said that, do you want the infill at such a low moisture content? If it expands later wont it stress the sides of the casting?

 

[gasman]

I might get shouted at by the traditionalists but as I said at the start I am using this to learn about metalworking and this step can always be done again.... so yesterday I did the cap iron screw - well almost finished anyway
I had bought some 8 or 12 inch lengths of brass rod - 1", 3/4", 1/2" and 7/16" from an eBay source and I was going to use a length of the 1" rod to turn down to get the level cap screw. However when they arrived I thought why not make it in 2 parts.
So I started by taking the 7/16" rod and using my new acme 7/16-10 die to thread it. The really irritating thing is I cannot find the photos on my phone of quite a lot of this so I have retaken some but some crucial steps are missing - very sorry no idea how that happened.
Anyway I needed 2 goes at using the die to cut the thread because the first time the thread was not square, but by tapering the rod slightly first on the lathe it was much easier and it cut so easily with cutting fluid.
When that was done I cut the 50mm of threaded rod off with a hacksaw, mounted that piece in the lathe and turned the end half inch or so down to 8mm diameter so all traces of the thread were gone from that bit.
Then I mounted the 1" rod in the vice and cut about 20 mm off the end

. I mounted that small piece in the lathe and turned the end flat - then drilled a 6.5mm hole in the end to 10mm depth and used a 5/16"-26 tap to tap it. I had recently bought from eBay a huge pile of taps dies and reamers so I have lots of sizes to choose from

I then found a 5/16"-26 die and threaded the 8mm diameter unthreaded part of my short length of acme-threaded 7/16" brass rod... and then screwed them together.
When this was then mounted in the lathe I turned it all square - and I figured that in the process this would tighten up the union between the 2 pieces due to friction. I thought it was worth a trial and it looks to be working so far as it is very solid

I still want to shape the end of the lever cap screw better, plus it needs knurling obviously - but at the end of yesterday it looked like this and I was reasonably happy as I had learnt quite a bit about tapping, dies, brass etc etc. I have plenty of brass rod left...

Cheers Mark

 

[gasman]

Mmmmm... no one has commented which leads me to think I have committed some cardinal sin in using 2 bits of brass to mke the lever cap screw. Oh well!
I turned my attention to finishing said screw.
First to knurl the knob. New skill to acquire as well. I looked at a couple of youtube videos and it all seemed straightforward - however don't think it has come out very well...
I mounted the knurling tool in the lathe and the lever cap screw in the chuck

I turned the lathe on at its slowest speed, manoeuvred the knurling tool till it was either side of the screw and tightened it slowly until it was engaging. Then kept on and tightened gradually...
It all seemed to be going smoothly but the final result was a little disappointing in terms of how precisely defined the knurling was. Anyone any ideas what I did wrong or how to improve?

Next stage was to shape the end - so I ground a curve on one of my lathe tools

Then, slowly and steadily cut a shallow curved groove in the top of the screw and then polished it out

I think I need to take the edges off the top and bottom of the knob?
Thanks for looking
Mark

 

[Jamesc]

Hi Mark

It's looking good. With regards the cardinal sin, certainly not in my book. It may work loose over time in which case an application of Locktite should sort it out.

Keep the posts comming, I am very interested in how it turns out

James

 

[Racers]

Jimi said you needed to get the diameter right so the knurls would line up after one revolution to produce a good knurl.

I like Karl Holtey ridged knobs (the knobs he makes, stop sniggering at the back) I think they look nice, have a look here http://www.holteyplanes.com/blog/page/2/

Pete

 

[gasman]

Thanks James and Pete - I have read a lot of Jimi's posts but must have missed that tip about the diameter. Given that the diameter of the 'knob' is 22mm, then there must be 3.14 x 22 = 69 ridges on the outside of the knurled screw. If each ridge on the knurling tool is 1mm wide, then I don't see how one can be that specific about the diameter because the diameter of the 'peak' of the knurling tool is different from the 'trough'?
Next stage is to drill the sides of the plane and locate the lever cap in the right place - I need some serious commitment for that move!

 

[Racers]

Long series drill bit and go all the way through?

I guess that the circumference must have to be divisible by the circumference of the knurling wheel.

Pete

 

[AndyT]

I have only a tiny experience of knurling. I think I have done it about six times so far. I paid no attention to the diameter of the workpiece but every time the knurls lined themselves up into a "whole number". I think there must be something in the way that the pattern gets established then reinforced that makes this happen.
The only difference I can see is that I turned the work round slowly by hand. (My lathe is treadle powered. )
I used the same sort of knurler as you. Can you try some experiments turning yours by hand?

And I agree that using two diameters of brass is sensible and economical.
The lever caps sold by Bristol Design use a brass knob and a steel threaded rod so they agreed with you for the construction method.

 

[rxh]

Your knurling looks good as far as I can see in the photo but if you are not satisfied you could turn off the the knurling and re-knurl, at the expense of ending up with a slightly smaller knob. I like to apply plenty of thickish motor oil when knurling, although some say that brass should be knurled dry. I have recently tried knurling by "hand cranking" the lathe rather than using a slow motor driven speed and the results were encouraging, which agrees with Andy's experience by treadling.

I'm not sure how much influence the relative diameters have on the quality of the result but I think what Andy has said above is plausible. My knurling tool has wheels of 51/64" diameter (20.4 mm) and I have used it with satisfactory results on brass of 1/2", 7/8" and 1 1/2" diameters.

Agreeing with Andy once more, I think your two part method is good. I have recently made a knob in a similar way and I applied Loctite as a precaution against unscrewing.

I like to cut small "steps" at the edges of the knurled area then remove the sharp edges slightly with abrasive paper - see photo below.

 

[Mr_P]

Just a thought but you don't have to knurl.

Keep up the great work.

 

[gasman]

Thank you gentlemen - all very helpful. I had another go at the knurling last night - and I agree hand-knurling better and more controllable. It does seem to me that once you start knurling and the grooves appear, they reinforce each other and the cutters of the knurling wheel automatically move into those grooves - I would have thought you need to think about the diameter the smaller the diameter as then the percentage ratio will be greater so proportionally greater shift of the knurling wheel to stay in the grooves. Not sure if I was clear there - I knew what I meant! I also cut a groove so the knurled section is in 2 halves now - will post photos tomorrow
Thanks again for all help. Big weekend coming - infill time!
Best regards Mark