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kbillan
11-12-2008, 10:46 PM
Greetins all- I am a newby- if thats not obvious.. anyway- I am curious how you change the tools when prompted= without loosing your reference to home.


I have also searched- and cant seem to find specific definitions to the following..

I am so embarrassed to ask this too..

Flute diameter
shaft diameter

there were others, i dont recall at the moment. But any info on tooling- or a point toward were to obtain that.. would be super appreciated.

I Just cut my first piece and it turned out well. But im sure it could be better. Some of the details were not cut and i assume its because i did not run the pencil tool path that meshcam offered... but again, i did this because i didnt know how to change tools..

thanks in advance=

Humbly

Keith

jalessi
11-12-2008, 10:59 PM
Keith,

If you want a quick tool change solution take a look at the Rapid Changer.

http://www.hightechsystemsllc.com/rapid_changer.html

You would preset all your required tooling in individual holders and program tool change stops in your cam software.

Hoss2006 also has a very kewl Power Draw Bar and Quick Change however it is not for the Taig spindle.

Jeff...

kbillan
11-12-2008, 11:01 PM
Cool- but i was really just looking for a way to do it by hand-- i suppose this is where you tell me there isnt one ;)


Keith

kbillan
11-12-2008, 11:08 PM
Also- looking at their vids.. my machine does not run that fast.. should it?

(taig)

jalessi
11-12-2008, 11:28 PM
**********Cave Man Solution************

If your tooling is close to the same length you can set Z zero with the first tool then when you are ready for a tool change remove the first tool, insert the new tool loose in the collet "So the tool will slide in the collet without force". Lower Z axis slowly until it reaches Z zero then tighten collet.

If the tools are longer be careful you don't bottom out before hitting Z zero.

*********************************************************

Using built in Mach3 software technology:

1: Setup Home / Limit Switches
2: Setup Auto Tool Zero
3: Use Auto Tool Zero After Each Manual Tool Change

There are many ways to solve your dilemma, others will chime in with better solutions.

Jeff...

Teyber12
11-12-2008, 11:35 PM
**********Cave Man Solution************

If your tooling is close to the same length you can set Z zero with the first tool then when you are ready for a tool change remove the first tool, insert the new tool loose in the collet "So the tool will slide in the collet without force". Lower Z axis slowly until it reaches Z zero then tighten collet.

If the tools are longer be careful you don't bottom out before hitting Z zero.

*********************************************************

Using built in Mach3 software technology:

1: Setup Home / Limit Switches
2: Setup Auto Tool Zero
3: Use Auto Tool Zero After Each Manual Tool Change

There are many ways to solve your dilemma, others will chime in with better solutions.

Jeff...

just to clarify-

You have your endmill in loosely, holding it in with one hand
you tell your z to go to 0
you "drop" the endmill so it rests against the table
you tighten it up
you go to home

Sounds like a good effective way :) thanks for saying that as i also had a similar question as the OP.

OP- tormach tooling is also pretty neat- it holds your endmill without the endmill sliding while storing, (er- can't put words on it) but it requires you to only zero it the first time, then you can just swap them from there on out

cheers

LUCKY13
11-12-2008, 11:52 PM
I dont think he is wanting a automatic tool changer. It sounds like he needs to know how to stop the program at the point he needs to make a tool change. And then how to restart it back where it left off.



Jess

jalessi
11-12-2008, 11:52 PM
Teyber12's detailed description is very good!

Your Taig is running slower than what?

If you compare it to a machine with more aggressive screw TPI it probably looks slow.

The Taig has 20 Turn Per Inch screws on all axis.

The reasons:

1: Very accurate resolution
2: Allows the use of low powered inexpensive stepper motors and stepper drive.
3:The Taig is designed to mill metal, the feed rates for metal with small tools are a lot slower than a wood router with a high speed spindle.

The Tormach quick change tooling system is also nice, I am not sure which one would be used on the Taig.

http://www.tormach.com/Product_TTS.html

Jeff...

jalessi
11-13-2008, 12:01 AM
The flute diameter is the tool cutting size. (See A on attached diagram)


The shaft diameter is the shank size. (See C on attached diagram)

jalessi
11-13-2008, 12:05 AM
Keith,

What kind of tooling are you looking for, what are you cutting?
What inside corner radius do you need?

Stepper Monkey
11-13-2008, 12:58 AM
A very easy way to rapid tool change by hand is to go to the hobby store and get the tiny little locking shaft collars used to hold wheels onto R/C aircraft. They look like your typical shaft collar, but are really thin and tiny so they can fit small diameter tools, and have a setscrew that uses an included allen wrench that looks like a sewing needle!
These come in common sizes down to even 1/8", so you can use them to preset all your tools, even the smallest ones. They are reuseable indefinitely and only cost a few bucks for a whole pack of them.

The trick is to use the above method mentioned a couple of posts back to get a tool to protrude from the collet a given measured amount, then you slide the little shaft collar up the tool as far as it will go until it rests firmly against the collet. Tighten the screw. Now when you remove the tool, it has a firmly mounted stop ring to index it the next time you use it. Every time you go to install that bit again, it will be in its pre-measured position everytime. Do all of your tools to the same set of known heights and it makes life really easy to swap them mid-cut or if one breaks.

I watched those videos, and yes, you should be moving that fast with your Taig. Also, you should not have your machine stalling when going faster than 2 IPM, nor while cutting in wax.
I was serious in the other thread, you need to get Mach configured right first before you do anything else. No matter what some people might think, 2 IPM is >not< normal.

If I remember correctly, Deepgroove used to just use straight Xylotex boards in a simple unmarked box with 24v supplies and unmarked black motors of around 270/oz rating. Is this still correct? If so, I can look up the specs for optimal settings for the Xylotex setups. Its been years since I've used one of those boards but I still have a few config files saved for them for use with Taigs, I think even one for a Deepgroove machine like yours.

kbillan
11-13-2008, 09:13 AM
Thanks for all of the replies, guys.

My collet/bit seems to have a tight tolerance and i dont know that that would work. Perhaps i should investigate this further. Maybe im using the wrong collet.. I am using .125 endmills.

and just as i suspected// flute diameter/shaft diameter.. exactly what i thought.


StepperMonkey-
I just looked at my mach3 setup= I was able to run well over 2 IPM last night. I reduced my motor velocity and accelleration in the motor tuning section.

Before, i had it up around 33 for velocity... and i took it down to 12.498 for velocity and 2 for accelleration. Now it runs easily at 4.5 IPM.. and if i over ride that= it goes faster. But it is still slow. Not like the machines on the vid.

As far as i know, yes.. they are like 270 or maybe 280 oz motors.. and the rest-- is out of my realm of info.. LOL


My newest issue- the tool change, is the one that is holding me back- well.. im sure the setup could be tweaked too.. but at the very least i was able to cut my first part out- so i have some sense of accomplishment. The part looks rough, and i think this is because i used a flat .0625 endmill to cut it out. My theory is that a ball end mill would run this much smoother.

I also did not do the pencil finish- so i am assuming that if I did, it would have cut the details around the center better? I have a lot to learn. i probably dont have my tools set up right either because you can see around the base where it looked like it double cut... This was why i asked about flute dia. and shaft dia...

these are the tools i have.. and i just ordered a few more.. Try doing a surfae clean up on a black of freshly cut wax with a .125" bit.. mind numbing.. ;)
http://www.bitsbits.net/index.php?main_page=product_info&cPath=33&products_id=286

here is a pic of what i got now.. not terrible for day 3 on this.. and the first attempt at drawing something with Rhino... (last time i drew something, it was 11th grade CAD (1996)

http://img145.imageshack.us/img145/9541/dsc02838xe6.jpg (http://imageshack.us)
http://img145.imageshack.us/img145/dsc02838xe6.jpg/1/w640.png (http://g.imageshack.us/img145/dsc02838xe6.jpg/1/)

kbillan
11-13-2008, 09:30 AM
and im retarded.

I just went to the Deepgroove website to look at the collet set.. i have been using the 3mm collet, for .125" endmills.. rather than the 4.. awesome. I can now see how that idea would work (lowering z onto the endmill)

thanks so much guys. One piece of the puzzle at a time..


Keith

Teyber12
11-13-2008, 10:07 AM
and im retarded.

I just went to the Deepgroove website to look at the collet set.. i have been using the 3mm collet, for .125" endmills.. rather than the 4.. awesome. I can now see how that idea would work (lowering z onto the endmill)

thanks so much guys. One piece of the puzzle at a time..


Keith

What type of material is that in the picture, and where did you get it?

cheers

kbillan
11-13-2008, 10:44 AM
What type of material is that in the picture, and where did you get it?

cheers

thats machinable wax- from machinablewax.com they have a banner here..

I took all of the shavings and melted it all down.. talk about an awesome material..

Keith

Stepper Monkey
11-13-2008, 12:23 PM
There are a lot of tricks to machining wax to make it go faster. As a jeweler I used to cut wax daily. You can use a fly cutter to surface blocks in seconds, and they cost $10-20. Just manually jog it across the surface as fast as you can, it will true the whole face at once. Taig even carries one but there are others. They also have the collet sets. Just with them directly and it will make life easier.
I run my Taig in wax at about 50 IPM. Now with an old school Xylotex 24v setup you won't get near that fast but the speeds you are getting are still really pokey even for it. You should aim for at least 10 IPM to start which is actually pretty usable.

Again, its all in getting it set up right to begin with, before you even need to woory about feeds, speeds, and SFM. In fact, if you are machining wax you don't even need to know those things at all.
You can simply run your machine as fast as possible and the spindle on one of the upper two pulley speeds, and you can be safe in the knowledge you will never approach the upper limit of your tools or material.

5artist5
03-23-2009, 01:43 PM
A very easy way to rapid tool change by hand is to go to the hobby store and get the tiny little locking shaft collars used to hold wheels onto R/C aircraft. They look like your typical shaft collar, but are really thin and tiny so they can fit small diameter tools, and have a setscrew that uses an included allen wrench that looks like a sewing needle!
These come in common sizes down to even 1/8", so you can use them to preset all your tools, even the smallest ones. They are reuseable indefinitely and only cost a few bucks for a whole pack of them.

The trick is to use the above method mentioned a couple of posts back to get a tool to protrude from the collet a given measured amount, then you slide the little shaft collar up the tool as far as it will go until it rests firmly against the collet. Tighten the screw. Now when you remove the tool, it has a firmly mounted stop ring to index it the next time you use it. Every time you go to install that bit again, it will be in its pre-measured position everytime. Do all of your tools to the same set of known heights and it makes life really easy to swap them mid-cut or if one breaks.


Is anyone else using this method with their Taig to do tool changes?
Is there a potential for a balance issue?

5artist5
03-24-2009, 05:09 PM
I got a bag of 1/16 collars from the local hobby shop and test fit one on a 3/16 shaft cutter. It seems that the ID is .004 larger than the OD of the shaft of the cutter. Keep in mind that the collar weighs almost as much as the cutter itself. So moving it .004 off center, will it add enough of a wobble to be of concern?

Keep in mind that I am very new to all this, I have only about three full days on the mill.
While I am waiting for the rest of my parts to do the CNC conversion I have been making
manual cuts and I am trying to come up with a reliable way to make sure that I can easily seat the cutters at the same depth, so this collar method seems like a good way
to go. But I am not interested in cutting corners if it will cause wobble or finish problems.

Are there other methods to have repeatable tool changes on the Taig?

jalessi
03-24-2009, 05:20 PM
5artist5,

Check while it is turning with a dial indicator on the smooth portion of the cutter, that will tell you if it is introducing run out.

Jeff...

5artist5
03-24-2009, 06:26 PM
5artist5,

Check it while is turning with a dial indicator on the smooth portion of the cutter that will tell you if it is introducing run out.

Jeff...


oK, i'll give it a try, thanks.

5artist5
03-25-2009, 11:16 AM
Ok so i Checked the run out with and without the collar and they both read the same
on my test indicator. It has .001 ticks and the needle fluttered between about .00075.
Of course that is a guess since there are no tics in between the .001 ticks.

I measured that at about .75" down the tool from the collet. Does this reading seem right
for a new taig spindle?

Also, let's say the needle flutters between -.001 and .001, is this considered .001 run out or is it .002 run out as it is really moving two thousanths?

Andre' B
03-25-2009, 11:48 AM
Also, let's say the needle flutters between -.001 and .001, is this considered .001 run out or is it .002 run out as it is really moving two thousanths?

That would be 0.002" TIR (total indicator reading) or 0.001" out of position, off center etc..

jalessi
03-25-2009, 04:13 PM
It would cause the cutter to cut .002 wider path if you milled a slot or a .002 larger diameter if you drilled a hole.

On very small diameter cutters ".005- .010" it could cause the tip to break because it would increase chip load beyond the cutters rated chip load.

Jeff...

5artist5
03-25-2009, 04:47 PM
hmm, what RPM should i be measuring for run out at? Maybe I was going too fast and there was a lot of vibration on the indicator and maybe the indicator wasnt following the
cutter all the time and instead jumping?

jalessi
03-25-2009, 04:51 PM
You can turn the cutter by hand and test for run out.

jalessi
03-25-2009, 04:55 PM
If it is vibrating the induced vibration will cause run out also, it will show up in what you are cutting

Will that small amount make a difference in what you need to cut?

I doubt the small collar is causing to much of a out of balance to cause the vibration though.

Jeff...

5artist5
03-26-2009, 11:59 AM
I measured again last night. I rotated the spindle by hand. This time the needle didn’t even move completely off of the zero tick in either direction. Again, my indicator is 0.001 increments so I don't really know what the reading is but it looks to be well less than 0.0005 in either direction.