MadModder

I did set up the jig, it's sketchy at best - but it did work.

Yeah it looks sketchy, yes it's made out of scraps, yup that's a 5mm end mill chucked in a drill press, and if you looked at it wrong bad things would probably happen. But it didn't need to survive for long, it just needed to be able to take a crescent shaped slice, about 0.75mm at its' widest, through 4mm of aluminum - 32 times. And it passed that test with flying colors, here's a completed rail still in the jig.

You don't get many chips taking that small of a bite.

I then started putting things together and ran into more problems. Since I'm using 2040 extrusions instead of the original 2020's, I needed to drill holes for 4 more M5 bolts - that hadn't happened yet. I don't know how much I'm paying the guy that drilled the holes, but it's TOO much. The exit point for one of the holes had about a 2mm offset from the entry, a LOT of file work later and that was corrected. You remember when I said that the M3 mounting bolts for the Y axis stepper would JUST clear the new 2040 extrusions? Well they do, they DON'T however clear the rail flanges. Take the rails/extrusions out, clip the corners off the flanges, and reinstall the rails/extrusions. Now, how much clearance do I have between the bearing blocks? WHERE'S THE FLIPPIN' BEARING BLOCKS? Take the rails/extrusions out, install the bearing blocks, and reinstall the rails/extrusions. NOW how much clearance do we have Clarence? About a mm, OK, a miss is as good as a mile. WADAMINUT, where's the grease ports? I'd installed the blocks so that the grease ports were pointing toward each other instead of away from each other. Take the rails/extrusions out, flip the bearing blocks around, and reinstall the rails/extrusions - for about the leventy-leventh time.

OK, now it was time to get serious and start getting this thing squared up. I made sure that both of the 2040 extrusions were in plane and perpendicular to the main side frame extrusions. I made sure that both the side plates were the same distance from the ends of the main frame rails, so the Y axis had a good chance of being perpendicular to the X axis. Then I went around and tightened the bolts, one last time. Annnddd...

Ya know that feeling, when the wrench suddenly loses all resistance and just spins round-n-round-n-round? Yup, I stripped the threads, and I THOUGHT I was being careful. And that's where I left it today.

I know that I ran the M5 threads at least 20-25mm deep in the ends of the extrusions, and I know that after going through the 15mm side frames the M5x20 bolts only had about 4-4.5mm of thread engagement in the extrusions. So there SHOULD be 10-15mm of good threads in the extrusion yet. My current plan is to get M5x30 bolts, that extra length of thread engagement should take care of the problem. (As long as I'm REALLY careful this time.)

I'm not sure if this chap is still carrying out repairs Andrew but when I spoke to him some years ago he said that he specialised in the older Siemens controls and servo drives.  At the time he was doing some work for a friend of mine who is the Heidenhain distributer in my area.

DW NC Solutions
Dick Westland
28, Spinney Hill Drive
Loughborough
LE11 3LD
Mobile: 07967757435
Tel: 01509 230479

I keep telling myself, the best laid plans of mice and men..... but it doesn't really help in these situations. 

I sometimes drill more slots than holes in a day. You don't want to get to the point where you're afraid to drill or cut at all, though, just because of the possibility of screwing something up. And besides, some of the most entertaining threads are where people rehabilitate something scrapped that has problems built into them. Reading about the fixes always creates a good feeling for me.

Anyway, onward and upward with this machine. I'm sure it is already better than the stock version! 

Not really practical for pens.  You have to glue a metal tube (usually brass) into a wood blank.  I use the thick stuff to fill any gaps, and you have to rough up the tube.  Regular wood glues wouldn't hold to the tubes very well, and you risk the pen coming apart in the future.

I also make pens out of solid surface countertop scraps, and that stuff is basically colored plastic.  The wood glues won't bond to it at all.  Since the tubes are really the structure of the pen, with the outside only decorative, you need a good bond for it to hold up.  I've made pens out of all sorts of materials, including corncob, acrylics, woods of all kinds, and even deer antler.

As to making your own, you only really need the in-line exhaust fan.  Everything else can be fabricated, except maybe the window.  I bought duct parts, because it is the easiest solution, but cheap dryer vent hose would do the job.

Well, ain't that just a kick in the teeth.

All the various bits and pieces have arrived, sooo...  I started assembling the Y rails, and guess what?  They DON'T fit!  I pre-assembled the tee-nuts onto the rails.  Since that would be easier than trying to pre-position the nuts in the extrusions - they would probably move around in the slots.  But I could not get the rails to slide into the slots.  The tee-nuts fit in the slot just fine, so i started looking for other causes.  When in the extrusions the tee-nuts were close enough to being on 20mm centers for using a digital-guesstimator.  The holes in the rails on the other hand were on 21mm centers, I know these were cheap rails, but still...  Where was quality control, aren't they supposed to check that kind of stuff?  Guess these rails must have been made on a Friday afternoon, or a Monday morning.  I've got a 5mm end mill, I'll probably set up a jig and just move all the holes, on all the rails, in one set-up.