Hoss ATC Project

[digits]

Originally Posted by hoss2006 .0000 My test indicator can't measure anything smaller. showed no deflection. before i drilled and tapped for the set screws, the endmill acted like a shock absorber from the air that couldn't escape and wouldn't go all the way in. good enough for who it's for

Nice looking tool holders Hoss - did you cut them on your lathe on your mill, or do you have a 'real' lathe as well?

Also, do you need to add some sort of groove in the flanges for an ATC, or will it just locate the tool holders via the flange?

[hoss2006]

Used my real lathe to make the holders.
The mill is in pieces right now.
Phase 1 will be a simple 7 tool rack, probably for (3) large and (4) small holders.
Figure that will be the easiest for the DIYer, Should still fit the stock X2 table.
Those with more than 4 inches Y travel could add on from there.
Be more programming for the Macro for Mach 3 than one similar to the LMS ATC
that moves to the same position each tool change.
Still have to get into figuring that out.
Phase 2 will be an articulating tool rack, probably an 8-10 tool.
Phase 3 will be a Scarlett Johanson robot to change my tool(s).
Hoss

[ataxy]

Originally Posted by hoss2006 Phase 3 will be a Scarlett Johanson robot to change my tool(s). Hoss

see thats the part i am interested in

[Willyb]

Hi Hoss

Sounds like a good looking project. Always wanted to build a ATC and someday I will. Interested in watching your progress. Keep up the good work.

Willy

[nine 16]

Hoss2006,

You are an inovative machinist to be sure!

Having just read this thread I do not recall seeing Z repeatability specifically addressed. If I'm picturing this right, an upward-biased spring-loaded drawbar will be in threaded connection to an R8 collet. When said drawbar is forced downward the R8 will disengage from the spindles non-locking taper and release its grip on the tool holder.

The tool holder itself will rely on it's flange contacting the botton of the R8 for Z control. The R8, if I recall, has a longitudinal indexing slot, so it cannot rotate.

Is there a need to positively restrain the drawbar from rotating? Is it assumed the springs will accomplish this? If the the drawbar does rotate a bit over time, might it not effect spring tension and might not the Z drift also? I understand that uniformity of tool holder shank diameter is important, but is that alone sufficient to deliver repeatable non-drifting Z?

Thanks, later
-Mark

[hoss2006]

Hey Nine,
With 600 lbs or more of spring pressure exerted on the drawbar constantly,
I don't think loosening will be much of an issue, but time will tell.
When it's at tool change, the spindle will be stopped (i hope) and the pin should keep the collet from being able to rotate.
No matter how much pressure is exerted, the collet isn't going to any higher than the point it clamps ahold of the tool.
The spring washers will wear out as time goes and need tightened or replaced.
I'll be leaving enough room to access the drawbar manually
since I still want to be able to use my other R8 tooling for other jobs.
I have another cool project in the works too, but can't test it till the mill's back up and running.
stay tuned.
Hoss
http://www.hossmachine.com
Note: the server was down for a couple days, they cost me money from the
missed clicks on the google ads.
One more time and i'll be going to GoDaddy.

[nine 16]

Hoss2006,

Yep. Restraining the drawbar from rotating should not be necessary. Even if it does rotate over time somehow contributing to Z drift, occasional Z rezeroing will make it moot. As long as the tool holder shanks are 'equal' in diameter the R8 will be prevented from collapsing more, or less, and disturbing Z too much. It is an X2 after all; mods such as your can easily be of equal or greater tolerance than many of the stock head and spindle components anyway.

Keep it up.
-Mark

[Bob Adams]

Your webpage is still down can't access it.

[hoss2006]

bob,
should be ok now, just checked again.
they posted a backup from last month, i had to re update it for today.
try hitting reload if you use firefox.
hoss
http://www.hossmachine.com

[hoss2006]

Hey mark,
you're right, I'll bet my quality assurance department is a little more picky
than the ones in china.

[Bob Adams]

Hey Hoss, no go on your webpage. What happened to your Yahoo group?

[pastera]

Hoss

For Z repeatability take a look at the Tormach tool holders - I made a few knock-offs for my X1 and the Z is repeatable of a range of drawbar tensions.

Aaron