[jimbo12d]

I am looking for something mostly to do 4oz or greater PCBs. The pcbs would be small 10"x10" at most. But I would occasionally want to use this for random aluminum projects.

I am considering the Lumenlab Micro for $699, but I am not impressed by the Z travel, only 3.375 inches (Closer to 6 inch+ would be nice). I think most bits are probably a few inches long and that would cut down on how far I can travel right? (I am not sure if router height is adjustable) Also, a 6 week lead time is not desirable.

Are there other options in this price range? How noisy is the micro? Can it cut aluminum at any reasonable rate?

Thanks ahead of time!

[jimbo12d]

I am considering this one also: Page Title

Does anyone have experience with Keling cnc?

[jimbo12d]

Any suggestions? Im sure someone has bought the lumenlab and can give feedback?? Or the kelling??

Thanks

[webjon]

. . . sadly I'm of no help as I'm in the same situation you are. . . seems like a TON of options out there, but scant information.

Haven't seen the Micro, it's interesting.

I like this one as well: Zenbot - Quality CNC Routers for Hobbyists and Professionals

[jimbo12d]

My only concern with zenbot and micro is they are made out of plastic. Zenbot seems even more wood and plastic based, not sure what it will stand up to in terms of tolerances or wearing down.

I dont think they actually use bearings, th plastic just slides on a rail which can cause wearing down and make the tolerances worse.

For the micro, it "uses NEMA-17 motors rated at 75 oz-in stall torque and 2a per phase. The driver it use in the syncRo 3 and the DIY amp kit (based around the Toshiba TB6560) has a peak current output of 3.5a."

The zenbot uses the same steppers

They have used it for aluminum, but that sounds a lot weaker then other cnc's.

The Kelling uses NEMA 23 185 oz-in motors and for about $100 can be upgraded to 425 oz-in motors from kelling.

Kelling is a little more expensive which is holding me back.

Also I am not sure what to use for a spindle on any of the machines. I am thinking a BLDC RC motor with chuck attached.

[webjon]

. . . I'm far more of a computer guy than a machinist, so it sounds like you are far ahead of me in that realm. . . But, according to the Zenbot site they do use bearings, and apparently slide on steel:

"Linear motion system with ball bearings preloaded on 1 " square 1/8" thick walled steel tubing on X axis and 1.25" square steel tubing on Y axis for ultra smooth motion with zero slop."

I also really like some aspects of the compucarve (mainly the length you can work with is huge), but the reliability on that is suspect at best.

I really wish there some reliable ratings or something. . .

[doorknob]

Also I am not sure what to use for a spindle on any of the machines. I am thinking a BLDC RC motor with chuck attached.

How would you plan to attach the shaft of the BLDC RC motor to the chuck?

What rpm range would you expect to obtain from the BLDC RC motor?

[jimbo12d]

HobbyKing Online R/C Hobby Store : 2848SL 3900kv Brushless Inrunner (WaterCooled)

going to use a mount like lumenlab did: micRo V3 - Lumenlab - Page 21

[doorknob]

OK, that's pretty amazing...

I still don't understand, however, how they connect the collet to the motor's rotor shaft.

What is hidden inside that block of HDPE? Is it just some kind of bearings, or is there something else?

Did they remove the original motor shaft and replace it with something else?

(While I've been reading about BLDC motor construction, I've never actually taken one apart or played with one - I'll have to look through my basement, because I seem to remember that a few years ago I bought some RC parts that have just sat on the shelf since then, and so maybe I have a BLDC and an ESC in there somewhere).

[jimbo12d]

I think there are bearings inside the hpde.

Also, I think that maybe it is a press fit collet. I have seen some press fit drill chucks for sale online, but cannot fnd the press fit collet style.

[xcayba]

The Zenbot does indeed have roller bearings that roll along the square tubes. The bearings have an axle that is then a tight press fit into the HDPE. I've done hundreds, if not over a thousand projects on mine over the past few years and it is still as accurate as it was on day one. It has no noticeable backlash and cuts very accurately. What I see in the simulator is what I am holding in my hand a little while later.