Saturday, January 29, 2011

A2ZCNC Leadscrews Upgrade - Fabricating the Z-Axis Stepper Motor Mount - Part 1

By looking at the title, you will know that I didn't finish the job.  It looks a simple part to make but still, I didn't make it.  There was an accident as I screwed up.  I'll show the pics towards the end.  The loud sound really scare the hell out of me... Mmmm... come to think about it, it is not a bad thing that the hell is out of me.... lame...

Ok, back to business.  After facing the aluminum piece and squaring it off in my previous session, I painted the top face red with a marker and layout the 4 holes to be drilled.  2 will be tapped M4 and the other 2 will be made into a slot with counterbore for the original sherline screws to be mounted at the end of the z column.

I originally planned to use a set of the holes to hold the stock down for profiling.  But given the size of the job and the holes pretty near the cut line with the capscrew head in the way, I decided to fasten the stock onto a pair of 123 block.


Using a 6mm steel dowel pin to find edges.


Drilling the holes...

Testing the tapped holes with a M4 SHCS. A little wobbly.  The tap was made in India. I changed to the Japanese tap I bought, much much better result.

Setting up for profiling of the little arc on the center front. Diameter of 10mm
 

The T-nut broke even before I started tightening.  Defective stuff.  Replaced and moved on.

A sudden loud noise and I saw the whole spindle swung to my left turning the column...  It was just touching the surface of the work piece...


More obvious from this pic.  Am I trying to make use of the 8-directional feature of this mill? Nay...

Think I'll fly cut the top face for a thinner than specs piece...

Looking straight at the mill.  The spindle is now facing around 30 degree to the left.

I hope I didn't wake anyone up with the loud noise.  I hit the e-stop pretty quickly.  Else the 1/2" endmill would have hit the clamp.  I must have done something wrong with either my setup or the approach.  I'll think about that for while before commencing work.  Looks like I'll be spending some time tomorrow to inspect the mill for damages and re-tram the machine.

On a lighter note, Mike (SG Tooling) sent me a pic of a leaf he milled onto a piece of pine.  He was demo'ing Vectric Cut3D and took the sample to this mill.  Nice stuff.

Whatever is the name of that leaf, it sure looks nice.  Good job, Mike!
Ok.  1.12am now.  Should be working till maybe 3am but have no mood after the incident.  I'll retire to bed and start again tomorrow.

2 comments:

Anonymous said...

You know, I have one of those tee nuts, broken just the same way.
Long ago I decided not to use end mill larger than 1/4"(6mm) on the Sherline. I had my 2000 do the same dance yours did too many times. I also learned that the column nut has to be tight. I really torqued on it and got it tight. That took care of the jumping to the side for a while.

GeneK

Wongster said...

The way the tee nut broke is interesting. It was twisted, it just "popped".
Tightening the bolt is tough, without moving the arm. I tightened a little at a time while tapping the arm back to square as the turning of the wrench moves the arm.
I think I'll cut real slow for a while (0.2mm per pass) and not want to be like those high speed moves shown on youtube... :)