Almost done with the mechanics

Today I've continued working on the mechanics. Everything is ready now. I only have to make everything level and tighten the bolts. As you can see, the extruder isn't attached, due to the problem I mentioned yesterday.

Just like yesterday, I encountered some minor problems. During the assembly of the x-axis, I noticed that there were no m3x10 screws for attaching the motor. So I used m3x20 with a lot of washers instead. It doesn't look as good, but it holds everything in place.

I also had to cut the bars holding the x-axis. They were made for the "default" Mendel and not the adjusted part I am using. So I had to adjust them from 495mm to the 463mm that I needed. Now I have 2 bars with ugly endings compared to the ones that were cut in the shop and have a nice and smooth edge. I also burned my finger during the process. I wanted to take the first bar after I cut it, but it was still too hot. Stupid me.

The bearings in the z-axis were really hard to get in place. There was not enough room for my wrench, so I had to use some small pliers instead. I think one of the bearings is slightly sideways because the left axis only turns if the lead-screw is slightly tilted to the right. I hope that won't be a big problem.

That's about everything I did today. I hope I can fix the extruder next weekend and attach the electronics and belts so I can start calibrating everything.

Starting to build

I started building the mechanical part of my Mendel this morning. I've encountered some small problems, but apart from those it went rather smooth. I started with the extruder. I couldn't find much documentation about it, so if I encountered problems I could ask for help while building the other parts. All the other parts have a nice 3D assembly that I can look at from every angle, but the extruder just has a few pictures.

Once I started building it, I noticed that the bolts didn't fit in the holes in the Idler-holder. I don't know why this is. Maybe Nophead printed the part with too small holes, or maybe Mendel-parts is using bigger bolts than the default ones, or it could also be a combination of both. The result stays the same, it doesn't fit. I don't really know how to make them bigger, as all my files are too big for that and my drill would make them round instead of hexagonal. Maybe I just have to buy a smaller file to do the job.
I also noticed an other problem. Because Mendel-parts assumes I use the older version of the driven-holder and I have the new version with the extra strengthening beam, the screw is too short. I'll have to buy a longer one for that. I should have checked it before ordering my parts.

After those small problems with the extruder, everything went rather smooth. I started building the x-axis. The wiki suggested to use m4x16 bolts for the x-idler-bracked. Those were too short, so I used m4x25 instead and added a second big washer so the belt is between two washers, which should be better for holding it in place. I didn't add the bars yet, as I'll do those at the end.

Once the x-axis was done, I started with the y-axis. The only problem I encountered here was that one of the bearings doesn't turn, even when the bolts are loose. I suppose its broken, so I put it aside. I think there are some extra bearings in the package, so hopefully I won't have to use the broken one. Again I didn't add the bars and went on to the z-axis. That one was easy, so I had a little time left to assemble the frame sides.

Below is a picture of my messy desk after a whole day of building. I hope the building will be done by tomorrow evening, so I can start adding the motors and electronics next weekend.

The last parts finally arrive

So on Monday the 11th my order from mendel-parts.com finally got shipped. It arrived on Wednesday, but as I only have time during the weekends I'm only posting about it now. The box was a little too small and the steel bars were sticking out of it. Luckily they were wrapped in bubble plastic. I hope they haven't been bend during transport. You can see the weird packaging on the image on the right.

Inside the components were packed in separate bags to make it easyer to find them. The only thing they could have done better is binding something around the kapton film, because it has some small dents and holes from other items pressing against it. (I removed it in the picture so you can see everything inside the box and not just the film) Everything else doesn't seem to have been damaged during transport on the first sight.

To have a better view on everything inside the box, I laid them out on my desk. The steel plates had a funny note on them that they could be sharp. It's like those sunshields for in the cars that say "remove before driving". Kinda obvious those things.

As you can see, the Gen 6 electronics are also in the box. There was even a certificate with them saying it was #14 ever made. They are really a lot smaller than the other types of electronics. I hope that doesn't mean that they can overheat faster. But I still have lots of unused ram-heatsinks if that would be the case. I made a closeup picture of them for you, so you can see how they look. I haven't taken the out of the plastic yet, as it could only damage them. I have enough experience with computer electronics to know that. 

Now that everything has finally arrived, I can start building mu Mendel. I know that I will get stuck at some point, but I hope someone will be there to help me. And now I'm going to start building. Wish me luck.

Mendel 3D renders

Yesterday I was looking on the wiki for some renders of a completely assembled Mendel. The only thing I found was a tiny picture of the front view. That's really too small to be of any use. I did find the 3D-models of an older version of Mendel made in Solid Edge. Luckily my university has a license for Solid Edge, so I downloaded and installed the software. Once installed, I opened the file and wanted to render it.
I got a lot of errors telling me that the included files had an absolute path reference to \\campus\files\MechEng\... well, just a very long path from a filesystem on a university. I looked for a way to fix them all at once. The only solution I found was putting all files in the same folder as the general-assembly.asm file. I was now able to see the whole Mendel in 3D. That will certainly help me once I start building mine.
I made some high resolution renders of the front, back, top and bottom for people without access to Solid Edge. If you click on a picture, you will be taken to a page with the small version of the image. There is a download button on the top left corner of that page. That's the one you need to download the big image. The images are over 1MB each, so you have been warned.
If you want a view from a different angle or from a specific part of the assembly, leave a reaction below and I'll render it for you.

Front view

Rear view

Bottom view

Top view