Lets see what you are doing to protect your steppers from coolant and chips

[maxboostbusa]

Im fixing to dive headfirst in my CNC project and along with it goes a flood enclosure so I was wondering what everybody is doing to keep coolant and chips out of the steppers. Description or Pics would be great. Thanks in advance.

[rexstep]

It's not an easy problem to solve because most solutions hurt the stepper's ability to shed heat. If you enclose a stepper in an aluminum box say, you are trapping it in there with the heat it gives off. This raises the ambient temperature causing the motor to run hotter than it otherwise would and put out less torque than it otherwise would.

If you can manage to put a fan on the enclosure without compromising its seal you'll have protected the motor while letting the heat out.

A second way: Mount the stepper so that the front opening is concealed by the motor mount and coupling/pulley cover. Use heatsink compound to seal where the motor and mount meet. Then brush 5 minute epoxy all over the outside of the laminations including where they meet the end bells. Brush some over the grommet and exit of the leads. After it sets cover the back opening with duct tape. This method will hurt heat dissipation slightly but if coolant is hitting the motor it will of course cool the motor as well.

Chips aren't likely to enter a stepper but dust and abrasives can get in through the bearings.


-Rick L.
www.homeshopcnc.com

[hoss2006]

I used some thermoformable plastic sheet from usplastics.com.
Wrote it up here.
Hoss

[Anokiernan]

I have 2 tons of spectrum aluminum lying around my shop so I figured I'd put it too good use. I left the rear of the enclosures open with an angled upper lip, that way the steppers are protected from coolant but are also able to release any heat developed. I also took the time to disassemble the steppers and seal them up with silicone RTV.

[dertsap]

does coolant affect the steppers , i thought they were sealed units , will the coolant eat the seals ? i'm just wondering out of curiousity if it is necessary to keep them protected

[Anokiernan]

Originally Posted by dertsap does coolant affect the steppers , i thought they were sealed units , will the coolant eat the seals ? i'm just wondering out of curiousity if it is necessary to keep them protected

When i was first building my flood cooling system i called up Taig and asked if the steppers were sealed, I was told they were and proceeded to build my system. Within the first 2 hours, both the x and y stepper fried. After opening them up it was very clear that they were not sealed and the boards were in an orientation that made it very easy to short out. I was able to fix both steppers with a bit of effort. Never again will I EVER run coolant without checking to see if the motors are sealed myself.

[dertsap]

thanks
thats interesting , i was always under the impression they were completely sealed

[LeeWay]

They do make some that are sealed. The average joe's though are not sealed perfectly. The sealed ones I have seen are white or cream colored.

I just got done finishing the rest of my way covers. Here are a couple pics.
I just used some .063" thick roofing rubber. Over the X motor, I just bent a little polycarbonate. Bent up a little aluminum for the Y. As long as you leave a drip edge on the sides so the coolant will drip off, you are probably okay. Both of these are open on the bottom. I am running 203V's though and these motors hardly even get warm. They don't get hot.

[maxboostbusa]

Very cool I will probibly use a little from each and it gives me a good idea of what is needed. Thanks everyone for your help.

Rick

[miljnor]

Wow a magnetic chuck on a mill?

You like living dangerously!

Hows that working for you?

[LeeWay]

No death wish and I'm not a thrill seeker. I took a page out of your sig line, Adapt, Improvise -- Overcome!
I hit upon the mag chuck idea as a bit of a work around. I cut splitters for tablesaws out of 11, 12 and 13 gage crs sheet. I was doing all this freehand on the bandsaw. Time consuming and not very accurate. I had mixed results using hold downs on the sheets. They just wouldn't pull flat without drilling holes in the waste in the center somewhere. I make about 40 different patterns of these and this was a lot of extra work.
The mag chuck pulls the sheets absolutely flat and holds them very well. Now this little vise is just sitting on the chuck, but it is attached with 4 pins to the 6" x 12" by 1/8" steel sheet and by 2 pins and a bolt on the 1/4" by 1' angle iron. I don't think my mill is capable of moving this vise once it's locked down. I can't move it by hand nor by using a mallet.
I was going to put a quick lock mechanism on this side under the vise and may still do that, but that will just add a little more security.
This magnet pulls with 270 pounds per square inch. 19,440 pounds holding power. That works. It also added some nice mass to the table. Really produces smooth cuts.

I am working on a plasma cutter as well, but it's on hold till spring, so this magnet will fill in until I get that done.

[miljnor]

Magnetic chucks have awesome down force, but its the shear that gets you, which is entirely a friction issue.

Even on grinders, they are usually set up with a stop in the direction of force, against the friction forces.

Cant see a problem with thin large surface area parts with small cutters, but I've been around awhile and mag-chucks, with Tall levers like your vice, are always a recipe for disaster.

So its a good thing you have extra hold downs on it.