Rear mount cut off tool

[jwmay]

Working on this now. My last project left me with a couple good size chunks of cast iron. I milled a ledge, so that it'll always mount perpendicular to the ways. Still have some cutting, drilling, milling and tapping before it's done.

 

[rwm]

Good project. How are you going to hold that down? If you use the T-slots that will be a heck of a lot of drilling?

 

[C-Bag]

This should be the top of my list. Every time I cutoff I’m reminded. Then other stuff pops up.

Good job.

 

[rwm]

Maybe a dual purpose holder to use for parting and for threading away form the chuck?

 

[jwmay]

How are you going to hold that down? If you use the T-slots that will be a heck of a lot of drilling?

The plan is to use the t slots. I quit for the day, to sort it out. I'll either mill a pocket for a nut, or drill all the way through it. But I have another idea that I'm working out. I just need some time to percolate.

Maybe a dual purpose holder to use for parting and for threading away form the chuck?

Ooh now there's an idea! I hadn't thought of that. Thanks!
My original intent was that it would carry two different thickness cut off tools on opposite sides. Flipping the tool holder end for end would have presented a different tool to the work. But then I saw that my 1/8" cut off tool insert holder is cracked. It's a funny shaped thing. So I abandoned that idea until I get a new one. No reason to go to the trouble of milling a special pocket into this for an insert holder that is almost broken.

 

[rwm]

The problem with my idea is that the parting tool will run inverted but the threading tool will run upright with the lathe in reverse. So having both tools at the correct height with one slot is problematic. Perhaps a second slot on the other side of the vertical? Then you turn it around depending on the application?

 

[epanzella]

I built a tool block for an old Logan lathe many years ago. One side was cut for a conventional tool holder and the other was for a cut off tool. I made a tapered spacer plate for under the the block to give me fine height adjustment by sliding it back and forth. (the center hole was slotted). Maybe you can take way something from that.

 

[jwmay]

Perhaps a second slot on the other side of the vertical? Then you turn it around depending on the application?

Almost exactly what I was thinking. Thanks!

One side was cut for a conventional tool holder and the other was for a cut off tool.

Yep! Thanks!

That moves the needle a little further to the right! The tapered piece has me stymied in the moment, but I think I get the gist.

It'll probably be the weekend before I get back to it. But the last two replies are along the right lines of what I want to do.

 

[Lo-Fi]

Nice one and welcome to the club! Rear mount parting is the best thing I've ever done for my lathe. +1 on a second slot on the other side of the post for a threading tool.

 

[epanzella]

The tapered piece has me stymied in the moment, but I think I get the gist.

epanzella said ; The tapered piece is just a fine height adjustment. Picture a 4" x 6' inch plate with a 4 inch slot down the middle. The piece is machined on a taper so that one end is .600 thick and the other end is .400 thick. It goes under the tool block and is locked down by same the center bolt that holds the tool block. By sliding the tapered plate back and forth you can get about .100" of vertical height adjustment.