Thread: A split-sole plane (part 1)

Originally Posted by Simplicity

...... never really going to happen guys, but you never know scenario, leaving a back door just slightly open.....

Matt, I spent close to 50 years in a profession where you always put an escape clause or two in the report......

Well, I went to the shed after lunch, to start cleaning up. I started by clearing some of the clutter off the metalwork bench, which uncovered the tray of brass scraps, & this short length of brass rod leapt out & said “Hey, I’m just the right size for a thumbscrew for that little plane you just made!”

I tried to ignore it & stick to the mission, but the brass insisted I change plans, so I chucked it up & made a thumbscrew with a 2mm disc to engage the slot which I cut in the end of the blade:
1.jpg

Now this is the part that always makes me nervous – setting up & drilling the hole for the stud for the thumbscrew to run on. It has to be centred, dead parallel with the blade bed, & within about 0.2mm of the right distance from it so that the disc on the thumbscrew will engage nicely & not either bind or want to slip out of the blade slot. The operation is complicated by the cross-piece I'm drilling being at quite an angle to the drill bit. The safest way I know is to start with a #2 or #3 centre-bit which have the least tendency to deflect (when new & sharp, which this one wasn't). Without moving anything after drilling, the hole is tapped using the DP to hold the starter tap straight. Both drill bits & taps want to deflect because there is no support on the “down” side as they enter, so a good deal of care is called for with both operations.
2.jpg

All good so far – the stud goes in nicely and looks straight. A bit of measuring up and the stud (a 6mm SS bolt) was cut off at the right length and neatened:
3.jpg

The blade slot needed a bit of adjustment to allow full lateral movement – I try to curve it just a little to match the radius of swing.
4.jpg

The curve is very slight so I do it by eye & if it’s absolutely spot-on (which I’ve only managed once), the blade will swing through its full adjustment arc maintaining precisely the same clearance with the disc. However, it’s not desperately critical, the disc needs to have good clearance in the slot so it doesn't bind, which will slew the blade as you turn the thumbscrew. A bit of extra clearance is better than not enough. Backlash is almost inevitable with this style of adjuster, the only way to eliminate it is to use a bearing that fits snugly in the slot as on the “Howard adjuster” (a very clever bit of lateral thinking there, Robert!). If you get it perfect, you’ll have minimal backlash no matter where the blade is positioned to cater for a slightly off-square cutting edge (& remember, with low beds it requires much more lateral movement of the blade to compensate for any error in the edge angle). A bit of backlash doesn’t bother me, so I don’t get too anal about it. [In the event, I’ve got just over a half-turn of backlash this time, which I consider a very good result]

So here we are, assembled & ready to test.
5.jpg

Hmm, slight problem Houston, either the plane body slipped in my Heath-Robinson vise/clamp arrangement, the centre-bit deflected, or the light tricked me & I didn’t set up as accurately as I should have (most likely explanation), but the stud is slightly out of parallel with the blade bed. This means the disc only barely engages the driver slot when the thumbscrew is screwed out to its maximum, but is fine lower down. When I tried to move the blade under just a little bit of lever-cap (wedge-cap?) pressure, the disc wanted to slip out of the slot & underride the blade. This has happened to me once before so I applied the same solution I did then. I tightened the stud fully & marked the top just behind the cross-piece. I then took it out, held it in my (aluminium-jawed) vise & using a solid piece of hardwood, pushed the stud to create a slight bend (just a degree or so) where it exits from the cross-piece. That fixed the problem nicely, and a drop of Loctite will keep it in position so it doesn’t move out of alignment. The thumbscrewl still screws all the way in, so it will continue to function as the blade wears down.

Whew! As they say, experience doesn’t prevent mishaps, it just teaches you how to remedy (some of) them…

Time for a test drive: 6.jpg

The adjuster works smoothly enough – I still need to use a small hammer for lateral adjustment, of course, so for me, the screw adjuster doesn’t make the process any quicker than doing both depth & lateral adjusting by the tippy-tap method, but the plane is going to have a new owner someday (& I hope several more after that) and as I've said before, I once thought screw adjusters were an absolute necessity on any plane, so maybe it will keep at least some new owners happy.

That’s it for this little plane, it’s distracted me as long as it could, but I can't fiddle with it any further. I do still need to temper the blade at some point, and although it worked nicely on the bit of jacaranda I was using as the test-bed, I’m not game to feed it to a lump of blue-gum for fear it'll be chip-city. Maybe I should, out of curiosity, just to see how much edge-chipping does occur….

Cheers,

Ian

Your little BU plane may still have one more distraction to occupy you yet. I think you mentioned somewhere early on that you would update your plane making guide.

As I have read through this thread I found myself thinking I could have used some guidance in this respect during the "plane challenge." It became apparent to me that filing the mouth was going to be awkward at best and impossible at worst. I researched commercial manufacturers and saw they had an adjustable mouth (on their planes: not so much their advertising language), but for the life of me I could not see how I was going to achieve that without milling equipment at my disposal.

Your split sole solves that issue although it would still not have been an option for me, because of the base material I used. However i would have had a better understanding of what I was up against.

Regards
Paul

Paul, yes, I think I asked early on in your plane build how you intended to make the blade bed. I was trying to direct your attention to the problem without being too explicit - might have invoked howls of favouritism from the crowd...

Never mind, you saw the problem & came up with a workable solution on your own, which is a far better outcome than having someone tell you "do it this way". You'r in good company (if my company is good!), because the first BU plane I made was this shoulder plane:
1 SP.jpg

When I started on this plane, my ignorance in all matters 'plane' was vastly more than it is now (30-odd years and 30-odd planes have reduced it a little). I had cut it all out and joined the sides to the wedge that forms the blade bed, and it was only when I was test-fitting the piece that was to form the nose that I realised I had a problem with how to get a blade in & out. My design (& the cutout for the escapement hadn't taken this into consideration at all (I was full of enthusiasm, but hopelessly naive!). So like you, I opted for a removeable toe piece, and upped the ante further by making it adjustable. The amazing thing is it worked reasonably well (I had very few tools at the time, & this plane really was "hand made".

I also sweated the body together with (lead) solder, which wasn't very difficult, as I recall. I later tried to do something similar with lead-free solder & failed miserably, which is one reason I seized on Peter McBrides idea of riveting laminated bodies when I saw it.

That first shoulder plane worked tolerably well, and in later years, as I learnt more about planes in general I re-visted it a couple of times and spruced up a few things (like re-doing the nose-piece to get rid of the terrible (first try) dovetails that held it in place, and removing the ridiculous 'horn' that looked like it belonged somewhere else.
6 SP.jpg 4 SP.jpg

I think by the time I was finished, I would class it as "good", though certainly not "excellent, but the lessons it gave me over the years are unbeatable....
Cheers,