Build Log, Mini Toolmakers Square | Project 4

[Andre]

I thought I might as well start a build log of my latest project, a small toolmakers square.
I have two shops, one in the basement and one in the barn. Splitting a single Starrett double square between two shops is a pain, so I thought I'd make another one.
The previous owner of the square has lopped of the blade of the square to 2.6". He was a genius! It's come in handy many times a 4" blade would not fit. So I will make my square of similar (actually smaller) style.



Here I saw out the stock, mild steel for the square and Starrett low carbon stock for the blade.



I left the saw running and went in for lunch. Mr.Groundhog came out to say hi.



After the stock is cut. What? It doesn't look like a square? Well I'll just have to fix that then....



After the stock was cut, I started thinning the blade. I will not use a standard locking mech, I will have two pins through the side meshing into a slot in the blade and the blade being clamped upwards against the pins. Much simpler (in theory) than the normal square lock. And simpler since I don't have a lathe.



Also notice how the milling on the ends of the square body are angled at 45*. I held the part between two V blocks, to ensure squareness against the sides. Not crucial, but it would bug me if they were angled since this will be hopefully surface ground sometime.

That's it for today, everyone. Next time I will cut the blade slot, add the pins, and drill and tap a long hole for the locking screw. If you want to follow along and build this yourself, feel free and I can show more in-detail shots of the process to making one.

 

[Andre]

A bit late on this update, but here is yesterdays progress.

Indicating, I used V blocks and tilted my vise for a reason, to use the V blocks to support the sides keeping everything straight and, well, square. If I just set it in the vise I would only be relying on the bottom to be perfectly square. Which it probably is not.



Trial scratch pass making sure I got it right, and it looks like I did.



I cut an 1/8" slot, then enlarged it with a 3/16" endmill, shown here.



Enlarged to 3/16", now I bump the slot out about .030" per side. At this point I'm a hair shy of .250".



Blade nearly fits, it will later be ground to fit at the surface grinder. At this point I decided to narrow the square body by about a .1" to make it fit better in the hand. I like it a lot better now.



Now I flipped it over to drill the clamp screw hole. Notice I did not use the V block and titled vise method, as this is not a very precise hole. a few thou error is completely acceptable here, but I'm fairly sure the hole is within .005". Or my vise jaw may not be perfectly square, it's an old vise so that's probably the case.



I cut a little counterbore for the brass clamping screw's knob. I like little details like this, makes the tool look better even though it does not affect performance.



Not shown, I drilled a clearance hole for the 8-32 lock screw. No need for 2" of threads and it would be a pain to remove for cleaning. Because there are only threads at the top .3" or so, I tapped from the top where the blade goes in. I would've liked to tap from the bottom as the clearance hole would keep the tap straight, but a 8-32 tap relieved that much (a factory tap would not fit in the clearance hole) would be too weak and would break.



The locking screw.



That's yesterday's progress. Later I will post today's progress (this was yesterday's). Hope you guys are liking this build so far.

 

[12bolts]

Nice work Andre

Cheers Phil

 

[Andre]

Nice work Andre

Cheers Phil

Thank you! More to come.

- - - Updated - - -

Here was today's progress. Not much.

Edge finding the bottom of the slot. Pins are going half way into the slot. In this case, they are .200" above the bottom of a slot.



And here they are. I used a .059" drill bit to start the hole then enlarging them to .063 in the dremel drill press. It left a nice snug, friction fit. Enough for loctite to go into, but not to sloppy to ruin the integrity of the square. After all, these pins are what keep the blade square.

 

[Andre]

got some work done today, cut the slot in the blade and installed the pins.


Clamped to the mini pallet:



Cut the slot. Took about 20-30 passes. Wanted to be very careful with my loose spindle and tiny 1/16" endmill.


Slot is 0.1" deep.



Pins installed and loctited. These pins are hardened steel, so I will cut the waste off with a dremel (do not want to break them off in fear they will break off under the surface of the body of the square.)



That's it for today.

 

[Andre]

Cut and ground down the pins. I gouged the side of it a hair but it will come out during surface grinding. I know the owner to a little shop here who has a little Sanford surface grinder that I will hopefully grind this square on. It has bad bearings so it won't look that great though but he said you can not measure the ripples so it's fine for this project.

 

[Andre]

Just an update to this thread, it's not forgotten. I still have to grind this square, and when I went to my friends shop he told me his Sanford grinder needs new bearings........so it leaves a rippled finish. He doesn't use it much only for flattening guides in the machines he makes so ripples are okay and bearing replacement isn't a priority.

Hearing this sorta put me off on grinding it, so I think I will either build a Brooks Stent cutter grinder and surface grind it on that, or hand scrape it.

 

[drs23]

Andre,

Love the long division in pic 5 and the post that follows. On your vise, no less! Who needs a stinkin' calculator anyway?

Do they still teach kids how to do this or a we just old farts?

 

[Andre]

Andre,

Love the long division in pic 5 and the post that follows. On your vise, no less! Who needs a stinkin' calculator anyway?

Do they still teach kids how to do this or a we just old farts?

Haha, well I did put a calculator in my box and use it for numbers that can't be incorrect. Like if I have a part with no extra material to remake, and working with long decimals.....I could probably do it fine on paper....or the vise ) and be fine, but a calculator is foolproof.
And I use my phone...er, ipod for sine calculations, square roots, and basic trig. Phones are more powerful than you think albeit touch screens suck in shops with oil and all.

It's still being taught in schools. I don't see why it wouldn't be.

Also, WD40 landing on the vise wipes the sharpie off. So it's a self cleaning doodleboard