Slotting 3.0 tube. New fixturing or reprogram?

E

evega

Plastic

Joined

Jul 22, 2018

• Apr 30, 2021

• #1

Another simple-ish job landed in my lap on this wonderful Friday. A part programmed by one of our 'senior" guys that has been a complete disaster all day. I'm sure I can tweak the endmill toolpath using the current setup but want to see what other ideas are out there.

The stock is 3.0 alumn. tubing with .120 thick wall, 32" long. I need to add two 1" slots that are about 12"long and some tapped holes.
The setup: HAAS head on one end and two vises w/ blocks under it to keep it level and stabilize it but not crush it either.

So- how to not crush this part yet keep it from lifting? Build a support arbor? Smaller tool? Different helix? Mill the slot profile only with smaller endmill?

So many options but prefer to not spend half a day experimenting.

Appreciate any ideas before I get back to it on Monday.

 

V

vegard

Aluminum

Joined

Jan 28, 2006

Location

San Diego, CA

• Apr 30, 2021

• #2

Try a hss corncob roughing endmill. They work well for really crappy setups

 

G

gregormarwick

Diamond

Joined

Feb 7, 2007

Location

Aberdeen, UK

• May 1, 2021

• #3

Maybe try a downcut endmill, to push the tube into the vice instead of lifting it out.

Variable Helix End Mills for Aluminum Alloys - Square - Downcut

 

E

evega

Plastic

Joined

Jul 22, 2018

• May 1, 2021

• #4

I was just looking at those the other day while looking for a different tool. Seems I missed a great idea !
Thanks.

 

Mud

Diamond

Joined

May 20, 2002

Location

South Central PA

• May 1, 2021

• #5

I use a shop made V-jaw on the fixed jaw position.

 

A

atex57

Stainless

Joined

Sep 6, 2006

Location

SW Wisconsin

• May 2, 2021

• #6

Thin tube is hard to hold in a conventional vise. How about those vises that have a fixed jaw that clamps to one end of the table and a moving jaw on the other. Clamp the parts from the ends and maybe a hold down in the middle. I remember seeing those advertised as a universal clamping system.

Ed.

 

E

evega

Plastic

Joined

Jul 22, 2018

• May 2, 2021

• #7

I need to rotate so I'm using a HAAS head. I did consider making an adjustable height arbor with swap-able plug/ center sizes though. My GM wants these done so making fun fixtures and rethinking the entire set up is a bit much for this run.

 

E

evega

Plastic

Joined

Jul 22, 2018

• May 2, 2021

• #8

That's a solid idea. I did notice that someone used all the new jaws so I'll need to order stock to make more.

 

Peter from Holland

Diamond

Joined

Jan 15, 2005

Location

The Netherlands

• May 3, 2021

• #9

Can you clamp it lenghtwise ?? Works better probably


Peter

 

Mtndew

Diamond

Joined

Jun 7, 2012

Location

Michigan

• May 4, 2021

• #10

evega said:

So- how to not crush this part yet keep it from lifting?

Click to expand...

Either make some Vee jaws, or use a tie-down strap lightly clamped in a couple of places next to your vises.

 

H

HuFlungDung

Diamond

Joined

Jan 19, 2005

Location

Canada

• May 5, 2021

• #11

I'd suggest making a support plug to go inside the tube at the chuck end so you can effectively apply some real clamping pressure with the chuck.

I've often used a 5C collet fixture (with axis laying horizontally) to support the far end of some projects. Only 'special' thing I had to make was a custom riser block to get the axis of the 5C up to the same height as the Haas indexer. Use a 5C clutch collet and machine it to fit the part OD. You can even use expanding collets in the ID. Just have to release the collet before indexing the part.

 

dandrummerman21

Stainless

Joined

Feb 5, 2008

Location

MI, USA

• May 5, 2021

• #12

You don't have a live/dead center for your rotary?

Get one. They are cheap. Even if you buy one now and it doesn't arrive until after you are finished.


For holding long thin wall tube in an indexer, make a plug like Hu suggests above me for the chuck end. Couple thou under your ID. I'm assuming 3 jaw chuck and not some other type of holding method on the rotary side.

Then make a plug for the center end, that has a shoulder on it so you don't push it deeper in the ID. Pop a centerdrill in it, and stick that live center in it. That'll give you positive pressure towards the chuck. It'll also keep it level, won't need vises, won't need to unclamp/clamp to rotate.