Wednesday, June 30, 2010
Tuesday, June 29, 2010
I finally have a few shots of my progress. I have completed the frame and installed the x-axis. My only problem is that the z-screws seem to project too far below the machine and raise it up off the feet. I haven't checked yet to see if I measured something wrong or if this is due to using nuts that are thicker than intended. I expect the fix to be fairly straightforward though.
Closeup of the z-axis 360 bearing and the x-axis motor.
The y-axis chassis is ready to go although I still have to do final adjustments on the bearings.
And, finally, a quick shot of the y-axis 360 bearings.
So, next steps are:
- Resolve the issue with the z-screws.
- Install the y-chassis and the bed.
- Install the belts.
- Move on to the electronics
I'm feeling pretty good at this point. the mechanical construction is almost complete. Since I bought pre-built electronics I am cautiously optimistic that they will work out of the box. That means that I could have a working Mendel within a week or so.
that is, if I can continue to work on it. Vacation is coming up and I need to put some serious time into getting my old '76 motorhome into shape for the trip. With a vehicle this old, that is only used once a year, there is always something to fix before we can head out so the Mendel may have to wait until we get back for the final touches.
I have ordered 5 lbs. of green PLA which should be here this week so I will be ready to build as soon as the machine is done. Then the real fun begins!
Tuesday, June 22, 2010
The open source powder printer chassis
Peter's geared drive mechanism for the bins
Monday, June 14, 2010
I am now installing the electronics on the two electronics boards and then it will be time to begin the final frame construction. Since the boards that I bought from Techzone are smaller than the original design I am trying to figure out exactly where they mount and how. I should have that straightened out today.
The main problem that I still have to face is that I have have not yet managed to get the gears off of my stepper motors. I tried to drive the motor shaft out with a punch but it seems to be very firmly attached to the shaft. Even a couple of shots with a 2 pound steel mallet didn't budge it. I have resorted to attempting to cut one of them off with the Dremel. I wasn't able to finish the job last night so I will be back at it tonight or tomorrow. if I can't get the gears off, or if I damage the shaft in the process, I will just have to order new motors. At least they are not one of the more costly parts.
BTW - Nophead, who made my plastic parts, posted an excellent article on his blog today regarding an enclosure for the entire Mendel. It basically acts like a heated chamber and can also be used to contain and control fumes. It looks like a good idea to me but I would probably mount the electronics outside the box. I worry that the heat inside might shorten their life.
Friday, June 11, 2010
It took me two weeks of spare time and hours of drilling, grinding and sanding to get all the subassemblies for the x-axis built using the cast parts. Even then, they didn't align properly when it came to installing them on the rails. With the properly printed parts I was able to build all of the same subassemblies in 2 hours and all of the holes for the rails align so they should go together just fine. I hope to have the whole x-axis together tonight if I get some free time. Since it has been raining here for days that seems likely.
Thursday, June 3, 2010
So, I will have to wait a week or so for them to arrive and then the build should proceed in a fairly straightforward manner.
In the meantime I will try to get the old gears off my motors and install the new ones. I can also finish the extruder build, except for the HeatCore piece.