Saturday, December 18, 2010

A2ZCNC Leadscrews Upgrade - X & Y Axis Installation

We just returned from HK Disney, reaching home at about 2am this morning.  We were supposed to reach Singapore yesterday afternoon at about 5pm but due to some technical problem with the aircraft, the flight back was delayed for 6.5hrs.  Other than being too cold for most of us, the trip was a good one, especially for the kids.

Spent some time in the shop this afternoon trying to fix up the precision leadscrews for both the x and y axes.  The process was simple enough except for the smaller hole size on the Super Gibs for the fastening wire.  Had to enlarge the holes slightly.  Some play observed on x but let's see if its serious enough after some trial cuts.

As usual, some pics.

Table, saddle, and motor mount were stripped off and the base cleaned.

Placing the new saddle on the base to mark out the new Super Gib.

Sawing off the excess on both ends.

The holes provided are too small for the stock wire.

Enlarging the hole a little.

Another problem encountered: the hole for the wire came too shallow.  It was drilled a little deeper.

As the new leadscrews are much bigger than the stock, adapters are provided to rise the motor mounts on both x & y.

Both screws mounted. I didn't take pics of the installation of the antilash nuts on the leadscrews and the table as I was very frustrated with fixing up the wire and the gibs.

Some videos of tests done:

Moving saddle by hand to see if the gib is set too tight. You can see the cut I have on my middle finger. This was from trying to fix up the cable to stream video from my iPhone to the roof mount LCD player in my car.

Motion test:

Simple backlash test:

I'll be doing more test to see if the play on the x axis would create some problem.


Anonymous said...

That's looking very good. You will really like the repeatability of those lead screws. Before I upgraded I made a cam for a friend out of steel so it went around the profile 30+ times.
You could see the shape of the X and Y axises change from top to bottom of the cam. That is what convinced me to change the lead screws.


Anonymous said...

Thanks GeneK. Hope I wouldn't suffer in terms of resolution. The 2 axes now move pretty quickly. Next will be the work on Z. I'll be following Graham's drawings to machine the adapters. I've more problem with Z with the stock leadscrews than the 2 horizontal axes.


Anonymous said...

If you use the Sherline steppers as I have, the Z axis is a real pain. I have to keep the acceleration quite low or I loose steps. If I remember correctly, you used larger steppers. I am quite interested in Graham's drawings to fit up the Sherline 2000 mill.


Wongster said...

I'm using 166oz in. SureStep motors bought from Soigeneris. So far been rather happy with them expect the lack of rear shaft for occasional manual work.

I was given an extra adapter (the horse shoe looking piece) to offset the stepper motor by Tim of A2Z. Do you know how I can measure the offset to make adjustments to Graham's drawing for the Z axis Anti-Backlash Nut Mount?

Anonymous said...

I measure things like the c bracket using pin gauges. Put a pin in the hole that fits snugly. Then use my height gauge to measure the height of each hole from the surface plate.
Next I measure the distance between center of the holes with digital calipers.
first measure the diameter of one hole and zero the calipers, then measure the distance to the outside of both holes.
We know that if you measure across both holes, it will be longer than the distance between the centers of the holes. That is why we measured the diameter and zeroed the calipers to subtract the two radii from the over all measurement.


Anonymous said...

Hi Wongster. You have a lot of great projects, it's fun and informative reading your updates. I have a Sherline 2000 that is CNC using IMService servos. It has A2Z upgraded X and Y (would love to get the Monster Z but it's out of my price range so I'm watching your Z upgrade with great interest. BTW, The CO. I work for is starting up a fab right now in Singapore (IMFlash). We had many of your countrymen here training for quite a while, great bunch of folks! Hope you didn't get the bug that's going around there right now.

Wongster said...

Hello Glen,

Thanks for your kind words. The mod is to have the precision leadscrew install on the z but not the rigidity of the monster mill. Maybe I'll search for a solution to improve that later.
Bug? Not that I heard of. Maybe common flu bug due to the colder and wet weather.
Do share with me what you're doing with your machines.