Improvements and printed objects

Mornin’ fellas!

In the last weeks I worked on my printer and made some improvements.

I printed a deer had for my grandpas birthday. It came out pretty good, all the details were nicely printed and the support material broke of easily, but I still had the problem of vertical waves due to layer shift.

not the best example but somewhat visible

The cause for this was that I had the printbed only sitting on 3 M8 threaded rods and a 8mm smooth rod on the four corners. The 8mm smooth rod wasn’t stiff enough to compensate the circling motion of the printed which was induced by the production tolerances in the threaded rods. therefore the vertical waves had the same pitch as my threaded rods.

I decided to fix this and bought 12mm smooth rods(they bend not a single fraction of a mm under force ;) ) and LMF-12-LUU bearings. 

Some cutouts were needed on the printbed and because I didn’t wanted to measure out all of it and draw it on, I made a 2d drawing of it in Fusion360, printed it 1:1 on paper and simply glued that on with superglue.  

Luckily I didn’t had to drill and file it to dimensions, because I have a very handy tool for my dremel(or better: the „replacement dremel-tool“ because the original Dremel only runs on full speed… 0 or 1… I have no idea why, maybe I should open it and  search for the cause). 

I really like this craving-bit, it eats away aluminium like a hot knife does warm butter.

After I had finished the cutouts, I screwed in the bearings and printed some suited clamps to hold the rods in place.

The result of my little modification was really pleasing. The waves disappeared completely and the accuracy went from +/- 0.5mm wall thickness to ~0.1mm. The fourth corner is still only hanging on a bearing and a 8mm smooth rod. I don’t quite like this, so I think I’m going to put in a 4. Z axis motor with a threaded rod for this corner to improve accuracy.

But for now my prints look really good. The surface is still not perfect though. I think I can blame  the filament quality up to some degree on this, because I bought a really cheap one. Furthermore I like to print at pretty fast speeds. Partially the fourth corner is also to blame as I said.

These are the things I printed with my improved printer:

This is a mug-holder which can be attached to the ventilation slits in a car. Here you can download it, I designed it: http://www.thingiverse.com/thing:1988960

fun fact: no support used...

Cheers,

JHL