Building a CNC mill based on X1 parts / extended axis kits

[Qwerty256]

I'm thinking about building a CNC mill based on the micro mill extended X and Y axis kits from LMS and micro-mill spare parts. I started out thinking about buing a micro-mill but realised I would end up replacing much of the mill and what I would keep is available as seperate parts..

These parts should provide what's needed for the XYZ-axis ways: Extended Y-axis kit #2297, Long table kit #2642, Column #2082, Spindle housing #2107.

I'm planning on using a DC tread-mill motor and build a driver for it (should be an interesting electronics project).

I don't need a real high-speed spindle, but I think 5-7000rpm or so would be a better match than the X1's max 2000rpm spindle for milling aluminum (which is what it will be used for most of the time). I don't think the stock spindle handle this.. Maybe with better bearings? Maybe a taig headstock would be a good option, but inconvenient shape to fit to the spindle housing (which I would need to keep because it has the dovetails to fit the Z-axis).

Are the leadscrews any good (it I add anti-backlash nuts) or should I go for better acme screws? (Would like to avoid ball screws because of cost, and may be hard to find something to fit in the available space?)

Comments? Criticism? Suggestions?

[Pres]

Sounds like a worthwhile idea.
The lead screws that come with the "extended kit" seem ok (for acme).
You will have to make/buy some lead screw mounting plates and bearings as well as lead screw nuts.
(since the "extended kit" uses the stock components from the X1 & you won't have them)
These axial bearings fit the lead screws well:
http://www.vxb.com kit981 Thrust BallBearings-8mmx16mmx5mm

Good luck,
Pres

[cncuser1]

Originally Posted by Qwerty256 I'm thinking about building a CNC mill based on the micro mill extended X and Y axis kits from LMS and micro-mill spare parts. I started out thinking about buing a micro-mill but realised I would end up replacing much of the mill and what I would keep is available as seperate parts.. These parts should provide what's needed for the XYZ-axis ways: Extended Y-axis kit #2297, Long table kit #2642, Column #2082, Spindle housing #2107. I'm planning on using a DC tread-mill motor and build a driver for it (should be an interesting electronics project). I don't need a real high-speed spindle, but I think 5-7000rpm or so would be a better match than the X1's max 2000rpm spindle for milling aluminum (which is what it will be used for most of the time). I don't think the stock spindle handle this.. Maybe with better bearings? Maybe a taig headstock would be a good option, but inconvenient shape to fit to the spindle housing (which I would need to keep because it has the dovetails to fit the Z-axis). Are the leadscrews any good (it I add anti-backlash nuts) or should I go for better acme screws? (Would like to avoid ball screws because of cost, and may be hard to find something to fit in the available space?) Comments? Criticism? Suggestions?

Take a look at Sherline Industral spindles.
They have a couple of different spinddles availablle, choices of bore, housings and motors with controllers.

[Qwerty256]

Originally Posted by cncuser1 Take a look at Sherline Industral spindles. They have a couple of different spinddles availablle, choices of bore, housings and motors with controllers.

The 6512-ER-16 looks ok, but I can't find any info on the maximum end mill/face mill sizes it can hande. Will search the forums to see what I can find.

A noticed the taig spindle assembly (both normal and ER16) is available seperately without the head stock, so that may be a better option than I originally thought.

I'm missing one important piece of infomation: the size of the hole in the X1-spindle housing. No dimensions on the assembly diagram in the manual.

[CountZero]

The range of collets for ER16 I have seen is 2-10 mm.

[Qwerty256]

Originally Posted by Pres These axial bearings fit the lead screws well: http://www.vxb.com kit981 Thrust BallBearings-8mmx16mmx5mm Pres

Wouldn't it be necessary to use a second bearing to support the leadscrew radially as well as axially? Maybe easier to use a double-row angular contact bearing?

[Qwerty256]

I'm debating using the replacement parts for Z-axis column and Z-axis leadscrew or getting the #2296 "tilting spindle, y-axis travel kit".

It basicly comes to down to two questions: which option is more rigid, and which leadscrew is better..

[Pres]

Originally Posted by Qwerty256 Wouldn't it be necessary to use a second bearing to support the leadscrew radially as well as axially? Maybe easier to use a double-row angular contact bearing?

Radial clearance in the block of a couple of thou would not effect the table position measurably.
But a couple of thou in axial clearance translates directly to table backlash.
It would be marginally better to use use "a double-row angular contact bearing" but I think certainly not "easier".

You need to precision bore out the mounting block and provide some way to secure the bearing race at its od.
Compared to just removing about 10mm off one face for the axial bearings.
Your call!
I did mine using "a double-row angular contact bearing" and after it was done felt I wasted time & effort compared to just using the axial bearings.

If you are going to use an offset motor and belt drive then some radial load will be incurred which could justify it.

Pres

[Pres]

Originally Posted by Qwerty256 I'm debating using the replacement parts for Z-axis column and Z-axis leadscrew or getting the #2296 "tilting spindle, y-axis travel kit". It basicly comes to down to two questions: which option is more rigid, and which leadscrew is better..

Not aware of any appreciable lead screw difference between them.

I would think it would be better not having another axis to "trim in" which is the case with the tilting column (beside the fact of it not being as strong).

Attached is a picture of the LMS extended base, without the tilt, compared to a stock X1, for your reference.

[miniumwage]

Hi Qwerty256
I'm working on a x1 cnc. just got my treadmill motor in today, but need to find or built speed controller. Keep me informed on your motor and controller build.

thanks
Chad

[Qwerty256]

Originally Posted by miniumwage I'm working on a x1 cnc. just got my treadmill motor in today, but need to find or built speed controller. Keep me informed on your motor and controller build.

I'm building my controller around a PIC16F877 microcontroller. The desired rpm is set by turning a pot and displayed on a 4 digit LED display. To sense the spindle speed I will use a sensor like the one I built to do threading on my CNCed Taig lathe: a small magnet on the spindle and a circuit based on a 3503 hall effect sensor to give one pulse per rotation. Actual motor control will be done using the PIC's hardware PWM driving a mosfet. (With an optoinsulator between.) Supply to the mosfet will be 308VDC (220VAC trough a bridge rectifier.) So far I have only tried it with small/low voltage motors and need to get some IRFP460 mosfets, some high speed optoinsulators and a streadmill motor before trying this.

[mohaon]

hay i am very very thankssssssssssssssssssssssssss