Need to hold a 1" ball nose

[tbaker2500]

First post here, looks like an active forum!
I've tried my best searching for an answer to this question. If it's already been answered many times, I apologize.

I have a new part that needs to use a 1" ball nose end mill. Not major cutting, just need the curve. However, I can't figure out how to hold the mill! All the ones I find online are either 1" or .75" shank. The biggest bit a TTS will hold is a 1/2".

Just cutting 6061.

Surely this problem has occurred many times and there is a easy solution I'm missing?

I am unsure how to go about cutting my own TTS blank, not sure how to get it precise enough?

Thanks for any help!
Tom

[zephyr9900]

The TTS R8 collet is .75", Tom. I have held a loooong flute .750" endmill in it for initial machining. Of course, once I progressed to the rest of the tools I had to touch down the first TTS tool to re-establish Z. Even if your part is fully contoured with the 1" ball-end, you should be able to find a surface (vise jaw, tooling plate, etc.) to touch down the first tool for a reference Z once you're done with it. Just a thought.

Randy

[SteveKoerner]

Buy the tool with 3/4 shank and "TTS it". The best way is to buy a 3/4 shaft collar from McMaster-Carr then machine out the TTS recess from the collar and just clamp it on. That scheme was described here before -- it works great.

[MFchief]

Hi Tom,

Welcome to the forum, hope you find it interesting and fun!

Is there a reason you must put your cutter in a TTS holder? Couldn't you get the one with a .75" shank and place it directly in the R8 collet in you mill?
Terry

[tbaker2500]

Ok, that's kinda embarasing. Yes, that seems like it could work very nicely. What about putting the TTS collar that tormach sells on it? That or the shaft collar should do the job. I only need about 5-10 thou repeatability on this pass, so a collar should do the job.

Thanks for the quick and intelligent responses!

[philbur]

Here's a low cost alternative:

R8 End Mill Holders (WT)

The added anvantage is no risk of pull-out.

Phil

[TXFred]

Thanks for the quick and intelligent responses!

You'll find that there's a lot of that sort of thing on this forum.

Frederic

[tbaker2500]

Here's a low cost alternative:

R8 End Mill Holders (WT)

The added anvantage is no risk of pull-out.

Phil

I've never used a R8 holder, my understanding is that I have to remove the TTS collar? So I couldn't use the TTS and the R8 tool holder without reconfiguring the machine? That's a downer if that's the case, since I have about 6 tool changes on this part. :-(

Thanks!

[rowbare]

See this post Making TTS-style toolholders in a Mill/Drill for one way to add a tts collar to a 3/4" shank end mill.

bob

[tbaker2500]

I got the bit in today, and I'm thinking that I might be able to mount a TTS conversion ring onto a shaft collar. I'll give it a try, and I'll post my results.

[Don Clement]

Here are some pictures of my TTS conversion of a ¾” shaft tool:





Don

[tbaker2500]

Thanks Don!
I don't have a lathe, although I could do it on the tormach I suppose.
Does the TTS flange have to be perfectly centered? I'm wondering is I could take a hefty shaft collar, and a TTS flange. Drill/tap and screw the flange to the collar, then I would have a 3/4" TTS adapter which could be moved between tools. ( I'm using an end mill, not indexed, so I will have to change bits every so often. )