Time to update this blog. There was not a whole lot of movement for a while because after getting the planes all put together, I set to lapping the soles flat. Well, the issue there is that because peening through rivets is less precise, the sole pieces were somewhat misaligned, much more than I could lap out. I tried using my little mill to fly cut the soles, but I only made it worse (I have come to find out that to cut steel in my little machine, I must use sharp HSS and not carbide, it isn’t rigid enough for that).
So to remedy that, I took them down to the local machine shop. For $30, they milled the soles nice and flat. The only thing is that they had to sneak them in between jobs, which took 4 weeks. And when I got them back, they were covered in surface rust, including inside the plane where the lever caps go. But I’m getting ahead of myself…
Lever Cap Screws
The lever caps are retained by custom made brass screws. These are made from 3/16” brass rod, that is threaded #6-32 on one end and left at 3/16” on the other. I made these on my little metal lathe. My first batch, however, I cut the slots by hand using my dremel. This resulted in slots of inconsistent depth and some off center. For planes like this, that simply wasn’t going to do. So I pondered the situation, and came up with this:
All this is is a piece of scrap aluminum, drilled and tapped at #6-32 and held in a little vise. The dremel cutoff disk is held in the mill in a collet. To ensure that the screw doesn’t move, I used a jam nut on the back, like so:
Then, I set the height of the disk to be on center (which was marked using a center finder and scribe). I cut the full depth in one go (I think it was like 3/32 depth), and we get a perfect looking slot, like this:
Lever Cap Goodness
While waiting on the machine shop, I also started working on lever caps. My prototype used 3/8” steel for the lever cap, which looks totally overkill, so on these I used 1/4”, which looks much better. I decided not to just wing it with the shape, and drew a design out in cad. I printed it out and marked the lever cap blanks, including the hold for the thumb screw. I roughed it out on my metal bandsaw, then worked the profile using both the belts and spindle of my ROSS.
One of the hardest things with lever caps is getting a nice rounded top. This is because it can be tough to hole the piece tightly through a 90 degree arc to get the rounded profile. On the prototype, I used a screw through the thumb screw hole with a jam nut. This worked ok, but it was very difficult to get the profile to be square to the side of the lever cap, which is not aesthetically pleasing.
To make sure that the rounded profile was square, I pulled out one of my angle plates. These are so handy, and are rather cheap. This one was 8 or 9 bucks from Enco and is way more square than woodworking ever requires. I just used a bolt through the plate and into the thumb screw hole. I used a machinist square to make sure it was all squared, and it was off to the belt sander:
I apologize up front for no images of this process, but I have described it a number of times, however here is a recap:
- Take a piece of round stock roughly the diameter you want (slightly oversized)
- Drill and tap through the center
- Cut off the desired thickness (plus enough to get rid of any cutting marks on both sides)
- Clean up both sides. Make sure the bottom side gets sanded to about 1000 grit
- Epoxy in a length of threaded rod so that it sits just less than flush
- Epoxy on a piece of wood about 3/16” thick. This can be square at this point
- Turn down the thumb screw (with the threads in a pair of nuts that have a slit cut in them, so you don’t mess up the threads) so that the wood and metal are flush
- Use a file and sandpaper and sand the whole thing up to 1000 grit
- Finish wood with some oil and wax the whole thing
In my case, I used some bronze I have on hand, which turns about like steel. It is much(!) tougher than brass. I decided to use end grain wood on these because this Burmese Blackwood has a really cool ripple in the end grain that is hard to get in a picture. I still need to cut the threaded rod down more.
Putting it All Together
So I started off by cleaning of all the surface rust. This was a huge pain, literally and figuratively. Use good quality sandpaper and change out paper often to make it easier. Getting in the mouth area was so annoying. If you are going to do as I did and have someone mill the soles, coat all metal surfaces in wax before taking it to them.
I filed chamfers along the front and back, but not on the sides. I felt the rounded profile of the top was enough. I then sanded up to 320 grit, and then used maroon and gray Scotch-Brite pads. This left a beautiful satin finish.
I wanted to prevent rust and had read of some people using Danish oil and wax, even on the steel. So I gave it a try, and it was disastrous. It was sticky and nasty and left a strange appearance to the steel. So I had to get rid of all of it using gray Scotch-Brite again. Then I waxed everything thoroughly. Just wax has to be reapplied every now and again, but it is cheap and easy to do and very effective. I coated the lever caps after finishing them 4 or 5 weeks ago and not a trace of corrosion despite sitting on my bench top that whole time.
Now, before the final photos, I have a confession to make. Somehow I managed to make one of the planes a 55 degree bed and the other a 46 degree. I have no idea how that happened, to be honest. It could be that it was put in the milling machine at the machine shop on an angle, but I haven’t cared enough to figure it out. It should still work just fine, but it was a bummer. I looked at it and said “That does not look nearly steep enough” and lo and behold, it wasn’t. Oh well, it has a mouth of only a few thousandths, so it should work well anyway, and I can back bevel the blade if need be.
Without further ado, here we are:
And with the prototype:
I lost track of how much time, but rest assured it wasn’t all that bad.
Now, before we leave, here are some
- 7/32” thick steel takes a while to cut
- Peened through rivets on something this wide is not a good idea. Drill bit flex comes in to play and alignment can be an issue.
- Measure your bedding angles very carefully
- Bronze is not equivalent to brass
- A strong belt sander would make life even easier
- Not all precision ground steel is equal. I have yet to find any as good as what Enco carries, but I have not tried several places still
Thanks for following along, our journey ends here
-- Brian T. - Exact science is not an exact science