Wednesday 12 October 2011

Whoops.

I have now added what I think are Lap joints to most of the joining parts of wood, except the top part, I guess I should also use Lap joints for this part, we will see.  I also intend to add support blocs in all the corners if needed. And have drilled the holes for the 8mm rods.  As I like to see how its coming I put it all in place (part way through) only to notice my first mistake. look close can you see the issue.



The Y-axis rods are centralised to the wooden frame rather than the Z-axis mounting.
What is the best way to resolve the issue, The choices I came up with were:
1) Re-drill the holes for the Y-axis.
2) move the Z-axis
3) just leave it as is and hope it does not matter.

I suspect I could have gone for 3 and it would not have mattered that much, but I guess mounting a build platform would have become an issue.
Initially I was intending to just go for 1 and move the Y-axis to the middle of the Z-axis mounts, but after in the end I decided I would rather maximise the XY build area and sacrifice a little bit of build height, so have opted for 2, also after looking at it with the wades extruder in place, i would have lost the Z hight anyway.

Next I decided I would mount the Z-axis stepper motors. This went relatively smoothly, with a couple hitches, first the holes I drilled were not perfectly positioned, so I re-drilled them with a 4.5mm drill bit for a small ammount of play in mounting, I think this has worked but won’t really know until I mount the Z axis and test.


The other hitch was the coupling for the Z-axis and threaded rod needs a hole 28mm across and I only have a 25mm drill bit, rather than go and buy a new drill bit I have taken the potentially foolish option and will just file the corners of the mounting bit down to fit (it only 2’ish mm of the corners)


I think it clear the one on the right is the one I have filed down a bit, I was quite curious how well this would file down, and it seems to work quite well, I guess on an actual thing, you would want to take account of the infill level. but here I just wanted it to fit, and am not too worried about the strength
As another quick visual check I have placed all the bits together again, and think is looking quite promising. (the top plate is accidently rotated 180 degrees) but it’s only a mock up.

A slight shame about moving the Z axis mounting holes is that the motor now sticks out of the side of the wooden frame. Something I did not really want but the Y-axis will probably have the motor mounted on the outside as does the Z-axis.

Also compared to a Prusa I have lost quite a bit of build area. At the moment I think it will be something like X:180mm  Y:160->205mm  Z:135mm

And unlike the Prusa I intend to rotate the Extruder by 90 degress, to save a little bit of space, Im not sure why this is not done allready. I imagin I will find out in the future, but for now that is the plan.  

Next I really need to figure out how I am going to mount the belt and pully for the Y-axis.

           


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