Mendel90 Sturdy - Build log day 1

Me and my friend Peter from the Norwegian reprap community ( reprap.no and bitraf.no ) decided to build ourselves  some new printers. It'll be his first, and my third one in complete, working condition.

We chose to build the Mendel90 Sturdy variant, since it have a lot of good press. I need a production machine to replace my wobbly oversized prusa, and since it'll be Peters first he chose the same, as troubleshooting and setup will be much easier we build two equal machines.

Here follows some pictures Peter took, with some short descriptions.

That's me, utilizing the kitchen table.

Sticky vinyl is highly recommended.

Thanks to Henning at zentrumreklame.no in Gjøvik for printing out the templates for us. I highly recommend printing on sticky vinyl like this if you choose to build a Mendel90, it makes the drilling a true breeze. Henning also taught us the proper way to glue the templates on. You place the template where it's supposed to be, tape down the centre part, peel back and cut off one half of the back, push on the vinyl from the centre and out, then you peel off the rest of the back and push the rest of the vinyl down, again from the centre and out. It's a good idea to be two when you do this.

Cheap ~€50 pillar drill did the job well.

Peter got a big sheet of 12mm and paid only ~€3 to cut it into enough sheets for three printers. The cuts were very good and perfectly square. Some of the sheets were slightly bent, though we hope it won't make any difference. We held or screwed two sheets together and drilled through them both with the template on top. This way we can easily make another printer without sacrificing the template.

Make sure you mount the brackets on the correct side of the panels.

Loosely screwed together. We forgot washers though.

It can be difficult to reach the screws with a standard drill, as the chuck is in the way. Luckily Peter had a set of very long bits, and the screws are torx, so it worked out fine.

Squaring up the front.

It comes together fast!

We couldn't get the motors to touch the base of the printer when we mounted the z motor brackets. They could perhaps benefit from being a tiny bit thicker.

A rare(?) shot from the back side of the Menlde90. Notice the sides aren't mirrored in size.

Unfortunately the x end motor bracket broke when pushing in the LM10UU.  

We plan to make a drawer or filament holder under the printer.

Bottom line after day 1?

• Sticky vinyl is great.
• Being two when drilling and assembling makes it much, much easier.
• MDF isn't that great to work with, some of the screws tore through the material and spun freely.
• Paint before you assemble. We don't dare to pull this one apart to do so now.
• I do think I would prefer using 18mm sheets, the 12mm seems barely stiff enough.
• The holes in the sheets doesn't have to be that perfect, there's good room to compensate in the parts.
• There are a whole bunch of 4-6mm holes all over the place for cabling. We chose to ditch them and rather drill a few 8mm holes when we decide where we want the electronics.
• I should have configured and exported new STL files to fit my nozzle size and layer height.
• Some of the parts doesn't behave very well in PLA.
• The x carriage can't fit a gregstruder (the motor crashes in the sheet). Moving the holes in the carriage 5mm to the front will do the trick.

That's it for now. Building RepRaps is fun!

-Nudel