Looking for information/help on X3 belt drive

[dneisler]

I have X3 working really nice with teh CNC fusion kit, and I wanting to do a belt drive upgrade and possible gan a few rpm.

Anyone have any links, pics, ideas, info, etc?

[SKICARB]

Don,
I have been trying to do the same thing on mine. Was planning on using a treadmill motor rated at 130volts DC driven by a KB motor controler.
My plan is to remove all of the gears from the geartrain, remove the motor bracket, machine a cogged pulley to fit the spindle hub, and mount the motor directly behind it, upside down of course. This will take a bit of work but it gets the motor up out of the way and I will have 2.5 hp with 4500RPM. I dont think I will lose very much low end torque because the motor is a lot bigger than the .8HP stock motor.

Does this sound workable? I am a machinist anyways so I believe it can be done.

[ViperTX]

Donald, how is the finish when milling aluminum?

[dneisler]

Pretty good, I am still tweaking on my Z which is what is giving me most of issues I think.
I am getting what I think is about .002 backlash in my X and Y just now starting to tweak my Z.

Here is a pic of a peice of Alum, not much, but it is right after the install before I started tweaking.
http://www.donald-neisler.com/index....ding-template/

[dneisler]

Back when I had my head appart I was looking, and I think I saw a way to use the factory motor, adding a belt pulley, and that is it. I need to pull it down and do some hard checking.

As for a resonable motor upgrade, what do you recommend.

[pzzamakr1980]

Hey guys, there are two ways you can go about this.

The first is what Donald is doing. Its much more expensive than what I have currently done but it should work pretty good. One bit of warning, those treadmill motors do not put out 2.5hp, but they should still be adequate for any drilling up to 3/8, maybe a bit bigger, if you are direct driving it. Also, depending on pulley size, you can run the mills right up to 5000rpm without any problems. Econobelt has a full range of htd5 belts and pulleys that work great. For the spindle get a pulley that is larger than 36 teeth, bore the inside for the spindle, and fit it right on there. The 36 have enough meat to bore and use.

The method I chose costs pretty much nothing, at least to increase spindle speed. The motor pulley and the other pulley that goes into the gear system can be switched around with a quick bit of lathe work, and will give you 6000rpm in high, 3000 in low. I have had no trouble at all with 6000rpm, but my mill is 2years old and has seen a lot of miles. I also fill the head with about a quart of synthetic motor oil, to help cool and lubricate. In low gear the mill was perfectly capable of drilling with a 1/2 in drill bit into 1in thick aluminum. In high gear, drilling is not idea, but using a 1/4 carbide 3 flute end mill, I can run my x3 at 30+ ipm in aluminum with flood coolant.

What I am doing right now, and I would be able to tell you how it turned out except I purchased the wrong size belt, is changing the final drive to a belt system (ala arc eurotrade writeup). I cut the gears off the spindle gear, turned the top 1/3 of it it to 1.635, bored the 30 tooth pulley to just under 1.635, froze the spindle gear, slid the 30 tooth on, and after the spindle gear warmed up, it was rock tight. I put some heavy duty epoxy on too, but it was probably unnecessary. I did the same thing with the final gear that comes out of the head, but with a 32 tooth. The gear got turned down to .75 about 1/3 of the gear, and the pulley was bored out to just under .75. Again, the gear got frozen, and the pulley was put on. Ill post some pics when its all done. The only thing I would change is to make the spindle pulley a 36 tooth. There was only about .002 of metal remaining between where the bottom of the teeth and the bore.