[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]

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.

[LeeWay]

I did some testing with it of course. It works the best when a bigger stock is used. The splitters I cut are usually around 8.5 " by 6". That is big enough to hold very well. Smaller parts don't fair nearly as well. You would have to take ridiculously light cuts. I always just try to use as much of the surface as I can. Haven't had anything slip yet while milling.
I tried just the vise initially and it won't hold up to milling. With the full surface of the magnet holding along with the angle on the side, it don't move. I will put a cam lock on this end of the vise though. That will lock it down really well.
I generally use 1/8", 3/16" and 1/4" end mills on this fixture.

This particular chuck does have the sliding stop on the left end for use with a grinder. I think they should come with those all the way around for different setups, but they would be real easy to install yourself too.
One thing I did notice is that this comes perfectly smooth on top. One of the first things I did was rough it up some. It has a little tooth to it now. Grizzly even mentioned that these are for grinding and light milling, so I doubt it unheard of. You just gotta insure that your fixture is using all the strength it can from the magnet and don't hog off 1/4" stock at a time.

[miljnor]

I don't know of anyone who hasn't tried this before , given the chance.

So its not like we all haven't learned our lesson.

Was just trying to save you the learning curve. But as always its easier to learn the hard way. And always harder to learn the easy way, especially when the easy way works so darn well, (until it doesn't!)

[LeeWay]

Don't get me wrong. I appreciate the wisdom of your warning. I am aware of the possible disaster it could cause. Light milling is all I ever do anyway. This machine could probably handle more than what I feed it, but it's only a semi production machine. Meaning if it runs for a couple days, I have enough parts for a couple weeks.
I will certainly lock it down though. Any failure would start with a slip and if I take that out of the equation, then I only have to worry about crashes. I always test new code pretty well though. I am always in the shop when it's cutting as well.
This is a temporary setup as I mentioned and hope to use it no more than just a few more months. If it works that long, I done good. If I screw something up because of it, you told me so. I haven't learned as much as I have by not heeding advise from guys that know what they are talking about.
You will be the second to know if I have trouble with it. Thanks for sharing your experience and cautions. I would much rather be aware of potential problems than ignorant or oblivious to them.

[twocik]

This cost about $3.00 to make and about ten minutes. You can find these at any home depot or lowes in the roofing section. I also used a rivet gun, and some silicone.

[Bowman]

I haven't tried it on my sherline but I once saw a setup that used plastic soda bottles cut to cover the steppers. They left the bottom open since any liquids would just drip off and this allowed for airflow. They claimed it worked well and it looked like it would make a perfect fitted plastic cowl for these size steppers.


Bo

[maxboostbusa]

Come to think of it I think I saw that somewhere too, I had forgot all about it. I do remember seeing some square bottled water at Sheetz last time I was there. Looks like I may have to go and get a drink and carry a tape measure with me. LOL Good idea thinks for the reminder.