POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

[Rex Walters]

75 ton cylinder
with some V blocks

The different skills and scales exhibited in this thread never cease to amaze me.

That's not a knoife!

 

[dkemppai]

I use a 4" on my Rockwell. The big trick is to saw off the back coolant trough! And DON'T bolt it to the center slot.

Look at the newer grizzly south bend 4" vices. Have one newer and one older style. Really like the new style for smaller mills. Not cheap, but otherwise been really happy with them.

 

[rwm]

I’ll have to think about that! Thanks ChazzC!

Today I worked on a handwheel. I still have to make a dial.

My fancy method of keyway cutting was just an appropriate size piece of hss in a boring bar mounted in the tailstock. Then lots of pushing and pulling, until it was deep enough. Truth be told, I went a little too deep.

Much easier to do this with the boring bar in the tool post and moving the carriage. You can advance the cross slide slightly each pass. I have cut several keyways this way.

Wait...did you really use the tailstock? How did you advance the cutter radially?

 

[Rex Walters]

How did you advance the cutter radially?

I’m guessing with the set over screws, but I’m mystified how a boring bar gets you even close to the right geometry? At a minimum, the bottom of the slot won’t be square unless you re-grind (and ruin the tool for boring).

I guess a brazed carbide chip might work, but unless the keyway happens to be the same width as the carbide chip, how do you adjust vertically in the tailstock and still keep perpendicular walls in the slot? And is ther enough depth for a slot?

It’s really not hard to grind a keyway cutter out of any scrap of HSS that you can mount in a tool holder to broach a key way!

I’m all for cheap, “ghetto” approaches to accomplish a one off, but this one has me puzzled since the normal approach is so cheap and easy. All you need is a broken center drill and a bench grinder!

 

[rwm]

Not a boring bar with a conventional cutter but a boring bar with a cutter the size of the keyway:

 

[Rex Walters]

Not a boring bar with a conventional cutter but a boring bar with a cutter the size of the keyway:

View attachment 458197

Ah! I see. It’s a terminology problem.

I think of a boring bar as the entire assembly to bore holes, not just the holder for the cutter.

I’d call that a keyway broach.

 

[GT-6 Racer]

Steady rest clamp for a 14” Clausing steady rest. To replace a missing part. 1018 CR.

 

[Mauzinette]

Nice work @GT-6 Racer

 

[jwmay]

Wait...did you really use the tailstock? How did you advance the cutter radially?

Loosen set screw, lower hss bit, tighten set screw. I imagine using the carriage would be as simple, certainly more accurate, and possibly faster.

I think of a boring bar as the entire assembly to bore holes, not just the holder for the cutter.

I’d call all of these things boring bars. I’d call a boring bar tool holder something that mounted in a machine to hold one of these. But…horses for courses! And that one on the far left works great, but it stretches my nomenclature choice a bit. Ha!

 

[rwm]

Ah! I see. It’s a terminology problem.

I think of a boring bar as the entire assembly to bore holes, not just the holder for the cutter.

I’d call that a keyway broach.

Old style boring bars (as shown) have a transverse hole to hold a piece of HSS for boring. By swapping out the HSS for the correct shape you can have a broaching tool.
Carriage is definitely faster. I struggle to measure the correct depth with this technique. I typically measure from the bottom of the keyway to the opposite wall of the bore and try to match the shaft + key diameter. Is there a better way? I suppose the keyway width is more critical than the depth, especially if you have a set screw that bears on the key.