Tool Changing for spindles without tool holders.

[aamir]

It's a custom made machine .
Manufacturer TPM Engineering Malaysia

[martyscncgarage]

I'm going to have this issue as well as the knee mill I am converting is an R-8 spindle and I just use collets for tool holders (right now).

I thought about changing each tool change request to an M01 (optional stop) and then make my tool changes by hand.

My tool library will have all tools set to 0 length and only have diameters in the tool table. I will have to set my tool heights using the knee and a gauge block.

As long as my tool change position is a constant I think I can make this work.

We will see, I'm not done with the mill yet.

Dave C.

Dave, consider using R8 endmill holders.
Also, another idea I use on my CNC mill is using a 3/4" Collet and ER32 collet chucks with 3/4" straight shanks. The chuck pulls up tight to the spindle nose. (Think Tormach TTS system)
I wouldn't want to do what you are thinking of doing with a CNC mill.

If you need a visual picture of one of my ER32 collet chucks let me know.

Marty

[Dave_C]

Marty,

Yeah, I agree, what I proposed was not very well thought out! But I'm not ready to test anything out just yet.

I thought about using the Tormach TTS system but then it is a lot of money so maybe R8 tool holders will be the answer.

I'm familiar with the collet holding system you mention and I'm thinking that would be even better.

I'm still going to be faced with the fact that I only have 4" of quill travel in the Z so going from spot drilling to hole drilling is a lot of change in Z length, more than the 4 inches I have to work with.

IE: Center drill is maybe an 1.5" down from the face of the spindle but by the time I inset the drill chuck and a drill bit I've added about 5" or so.

It is the one big draw back to converting this Knee mill!

I've checked my X and Y travels with the screws installed and I have 21" in X and 8.5" in Y!

Dave C.

[andyolney]

Dave - I have a similar machine I converted years ago. You are doing a super job, much better than what I have done.

I move the knee on mine, which has the advantage of 13 or so inches of z travel and no cranking. I put a 4 inch or so 3mm pitch pulley on the screw, as close to the bevel gear as I could manage and cobbled together a motor mount up inside the casting. I also put a gas spring in to help out the motor, sizing it by sticking a bathroom scale inside the base. ( 100 lbs? Don't know the exact #).

I retained the original leadscrew, thinking that the weight of the knee would minimize backlash.

Andy Olney

[Sportbikeryder]

Whilt not suite on topic, here is another option for "unusual" tool changers. This is not an Acorn based machine, only posting to show the action to possibly provoke ideas for others.

https://youtu.be/HCzP9PqdoVE

[martyscncgarage]

Marty,

Yeah, I agree, what I proposed was not very well thought out! But I'm not ready to test anything out just yet.

I thought about using the Tormach TTS system but then it is a lot of money so maybe R8 tool holders will be the answer.

I'm familiar with the collet holding system you mention and I'm thinking that would be even better.

I'm still going to be faced with the fact that I only have 4" of quill travel in the Z so going from spot drilling to hole drilling is a lot of change in Z length, more than the 4 inches I have to work with.

IE: Center drill is maybe an 1.5" down from the face of the spindle but by the time I inset the drill chuck and a drill bit I've added about 5" or so.

It is the one big draw back to converting this Knee mill!

I've checked my X and Y travels with the screws installed and I have 21" in X and 8.5" in Y!

Dave C.

I think you will do ok with the quill travel. Short bits and end mills.
Its going to be a nice machine!
Either buy the Tormach 3/4" Collet or modify one like I did.
Buy 3/4" straigh shank ER32 holders. Many dealers on ebay. That's what I did. I don't own any TTS holders....just borrowed the idea.
Marty

[cnckeith]

Keith I've looked for M6 macro which I presume you call mfunc6.mac and there isn't one in my cncm folder. goes 3, 4, 7,8, etc but no m6.
Is this normal.?

yes, if there is no custom m6 it defaults to the mill tool change default action which is.. 'goes to tool change position, displays message to change tools, waits for operator to press cycle start to continue. etc..
scott will post the macro with the tool measure/z reset in the tool change on monday and you guys can simple copy paste and try it out on your systems

[jazzcnc]

yes, if there is no custom m6 it defaults to the mill tool change default action which is.. 'goes to tool change position, displays message to change tools, waits for operator to press cycle start to continue. etc..
scott will post the macro with the tool measure/z reset in the tool change on monday and you guys can simple copy paste and try it out on your systems

Ok, that's what I suspected. Thank you.

[cnckeith]

viewtopic.php?f=60&t=1464

[diycncscott]

Here you go: viewtopic.php?f=60&t=1466