Tuesday, 28 April 2009

BIG CUTS across the board...

I used my new workbench and jig-saw to cut the MDF - took about an hour. Then I did the threaded rods, cutting through the hardened outer with the saw and then snapping off. The first one was harder, the second cut easier and the third cut middling! Guess the material isn't consistent. That took another hour. Then I cut the U-shaped channels. Although I started with the jig-saw, it was easier, actually, to use my Boa saw (a kind of hacksaw, only better for this kind of thing).

The workbench has well and truly been christened - I used it at three different heights depending on the job in hand, but I took a graze off the top of one handle, off one side of the top and onto the metal top support too! (Design-flaw: these supports need to be lower to avoid the jig-saw blade depth.)

I filed off all the sharp metal ends as I went with a little hand metal file.

Cutting the aluminium angle and filing off any sharp bits took about an hour and a half (again starting with the jig-saw but swapping to the Boa) and cutting the PTFE took under an hour. Don't try cutting this with a jig-saw - just doesn't! I filed all the fluffy cut edges off with the same metal file.

The only thing I've not cut is the PTFE rod. I haven't decided exactly what I'm doing with that yet.

1 comment:

  1. If I could make an observation about your design choice based on similar choices I made...

    The threaded rod work very good for moving heavy loads or moving very accurately, assuming you've incorporated some anti-backlash mechanism, but they are dogs for speed. I've found that my biggest problem has been speed.

    Once I tweaked the frame into alignment and got the axis moving smoothly, power was the least of my worries. I found I could not move the stages fast enough to keep up with the slowest speed of my Mk II extruder. Granted, you may have better slow control over the new pinch wheel and feedback type extruders, but if you are using an Mk II, you may have the same issue.

    My friend is now building his own McWire-type RepStrap and we are putting on a rack and pinion type drive system to combat just this problem. We've got the x stage on the rails and it slides like butter at this point. We don't know how fast it will go but it will be orders of magnitude faster than the threaded rod drive my machine has.

    Just food for thought. I've experienced much frustration over this issue--it's effectively kept me from printing on a machine that otherwise works.

    Glad to see you posting so often!