[MFchief]

Hi all,

I'm looking for input on using one of the relatively inexpensive imported water cooled hi speed spindles. I'm curious if anyone has ever tried using the coolant on the mill as the coolant for the spindle? I use Koolmist 77 currently and if it could be plumbed into an auxiliary spindle instead of using a completely new source to water to cool the spindle, it would sure make life easier.

I don't have any idea about the plumbing of these types of spindles, if there is a "water jacket" type setup, or the coolant actually makes contact with the components of the spindle.

What I am considering is one of the relatively low power, 0.8 or 1.5 kilowatt units to use for mainly engraving.

Thanks

Terry

[WOTDesigns]

I would have to think the coolant would gum up in the the jacket over time, and You would definitely need screens as even Kool Mist develops gummy white or blue crud. As cheap as some are it may be worth just trying it and see.

I went with the Tormach speeder because I need the whole 18" X travel. It's actually running right now breaking in the bearings. $260 to have it overnight Saturday delivery via UPS yesterday. I have 4000 parts to slot almost an inch deep with an 1/8" EM. If it shaves a minute off the 2.5 minute/ea cycle time I save a week. Not bad.

Brian
WOT Designs

[LSM]

My fadal has spindle coolant they use dowfreeze more like antifreeze then coolant no need for lubrication and such,
the main purpose is to help with z axis stability, same with the ballscrew cooling.
on the tormach I would just go with a speeder

[WOTDesigns]

I can now attest to the glory of the speeder! 2x 5" vise and one 4" Machinist vise on the table each holding 12 parts. Used to run 53 minutes with 0.125 em, 0.9 stick out, 0.075 doc spiral slotting (total slot width 0.145) at 5140rpm 12ipm.

After some program tweaking and switching to 3 Flute (after breaking 6 2-flutes trying to find speeds and realizing flood not Mist ) I'm running the same depths at 25ipm and running the whole lot of 36 in 33 minutes.

I have tried 3 flutes on this job before and they always broke. Maybe they just like the additional speed???

On this run alone that will save 14 hours of cut time on the first half and likely similar on the second half of parts. 28 hours at 60/hr = $1680... Funny how it literally exactly paid for itself on the first job.

Brian
WOT Designs

[MFchief]

Thanks for the input guys.

My thoughts would be:

As to "gunking up" the spindle, almost certain to occur, as Brian suggested. Might still be acceptable since I could flush it pretty easily when it's off the mill.

Using a different coolant, such as the dowfreeze used on LSM's Fadal would likely work, but would negate the advantage of using the existing coolant supply on the Tormach.

The speeder is definitely an option, but seem like over kill in power and cost for engraving. Plus I have longer range ideas of using the auxillary spindle on a cnc router as well.

Terry

[tbaker2500]

From what I saw with these spindles, just use a small pump and coolant used for PC cooling.

[MFchief]

I ordered a spindle/VFD setup this afternoon, so I am going to give it a try with the mill coolant, if inspection of the spindle makes it seem feasible. I did change my mind and went with a 2.2 Kilowatt unit, instead of the smaller one, since that would be large enough for the main spindle of a router setup.
I'll post after I try it to let everyone know if the idea works out or not. The router plan is hopefully going to use my old series II Tormach steppers and drives, since I did the series III upgrade last year.

Thanks again for the input.

Terry

[tbaker2500]

Let me know how it works out, I'm interested in how well the spindle works.

[victorofga]

I check it every day... when I see less flow, then I just blow trough with pressured air ... backward in the return hose.. takes no time..

I also using a catlitter box... it is small so with continuous use I have to refresh water likely 4-5 hour..

I think a larger, 15-20 gallon tank would be sufficient without changing or even cooling the water..

[GLCarlson]

I went with the Tormach speeder because I need the whole 18" X travel.
Brian
WOT Designs

For what it's worth...I built a concentric mount for a DeWalt variable speed router (precisebits.com has a lot of info on what to use, collets, etc). I've now got 5-25K rpm over full table travel with capacity for 1/4 and 1/8 shanks and around 2 tenths runout. Lost about 8" of z axis movement...which, after I thought about it a bit, meant that the wear would be on a part of the column that isn't used much. And small mills don't have much depth of cut. Still plenty of room to mount a vise or workpiece. Total project cost, including the router head, was under $100. Early days yet, but so far works fine.

[WOTDesigns]

I like the 25K a lot! I've though about a concentric mount but seemed challenging to create much rigidity without being a PITA to mount. Love to see some pics!

Any issues with coolant?

Sadly I barely have time to tie my shoes much less make a mount and R & D something that is available and quickly removable. Love to see the design though.

Brian
WOT Designs

[MFchief]

I'd also love to see some info/pics on a concentric mount design! I looked at precisebits.com, they have some neat goodies, I especially like the 1/2" shank, ER16 adapter.

Terry

[MFchief]

I wanted to get back and maybe close out this thread by reporting my progress.

I ended up getting a 0.8KW spindle to use as an auxilary, mainly because of it's smaller size. When I received it, I decided not to try to use the mill coolant to cool the spindle because the paper work that came with the spindle implied the coolant actually came in contact with the electrical parts of the motor, stating that anything other than liquid might cause a "jam" of the motor. I don't have any idea how true that is, but did not want to disassemble the spindle to find out, I was concerned that a small chip might make it thru the coolant loop and short out the motor.

I fabricated a mount to attach the spindle to the mill and mounted the VFD and coolant tank to a small shelf hanging from floor joists, since my mill is in an unfinished basement. I haven't yet cleaned up the install, to properly secure the wire and coolant hoses to the spindled, I was eager to do the test run. LOL

I made my first runs today, and so far am fairly happy. I am glad I opted for the water cooled spindle verses air cooled. It is amazingly quiet, even at max rpm! Not having a fan really helps. I tried using a carbide 60 degree engraving bit such as are all over eBay and a 0.025" end mill, basically because that's what I had on hand. The results with the small end mill were much nicer for me. I would appreciate any suggestions from experienced engravers concerning the best bits to use. The spindle max's out at 24K rpm.

I attached a few photos of my set up and the test block with a small American flag engrave to 0.005". I apologize for my lack of photographic skills!

Terry

[tbaker2500]

Nice!
How's the runout?

[MFchief]

It seems pretty good to me, especially for such an inexpensive spindle ($180 US). With the ER11 collet that was included the runout was .00075". Measuring without a collet on the inside of the spindle it was only .00025", so I expect with a quality collet it will be somewhere in between.

Terry

[tbaker2500]

Thanks.

[TurboStep]

If you're considering purchasing additional collets you might be interesed in this thread:
http://www.cnczone.com/forums/genera...e-spindle.html
Regards
Step

[MFchief]

Step,

Thanks for the heads up! I checked my collet nut and it is a type A so hopefully it will work out OK.. I ordered a collet this morning, so I guess I'll see......

Boy they don't make it easy, do they LOL

I also have one of those ER11 stub spindles I got cheap off eBay with the intention of someday making a floating tip engraving tool. It has the type M collet nut, and they are definitely different, that nut is quite a bit smaller in thread diameter, It didn't come with any collets, so I need to research the proper ones for it.

Terry

[kstrauss]

Who supplied your spindle? Did it ship from a US source, Chinese or...?

[MFchief]

It was these guys, equipmentwholesaler1 on eBay.

They are a Chinese company, but they do maintain US inventory, I believe in California.

Terry