Major gantry update. and complete mechanics.
I have some more work to do on the belt drive, and mounts. but the basic mounts and mechanics are done. the igus bearings would be able to be added to this build if someone was wanting to them. this video served as some inspiration.
https://plus.google.com/100827274652904341735/posts/LEx4fzmU2hk
Z axis screw mounts need to be added.
I am starting a “typical” BOM. but it will change slightly from. And all of the parts are parametric.
Repo at
I think the question would be…why is my experience different? Humidity? Lubrication? Belts vs line? I seriously doubt the problem was alignment. You had rods that rusted in short order…stuff doesn’t rust in Colorado.
When my delta starts making noise with it’s linear bearings…it needs lube.
I used JFM (I have no idea what I’m talking about here, I just read the label. 
) But those are significant discovery points. Bushings (metal or otherwise) need adequate rigidity and adequate length along the shaft to establish accurate movement.
(I’m setting the printer up now to print a lot of little shapes, we’ll see how they turn out.) I’ll also admit my ‘belt to gantry’ connection is…goofy. I was planning on improving them when the printer was making plastic.
White lithium grease. My printrbot was crazy loud until I added lube
If used lithium grease but have moved to Silicone superlube
I just wipe/spray a little on the shafts and let printer movement handle the rest.
I’m still playing with plotting, but you’re right, smaller circles are kind of square. I dunno if its the pen dragging, a controller issue, or the igus bearings. Will post samples later today.
I’ll want tuned prints before that. 
Are you just doing that on the sled, or on everything that slides?
I am planning on using LM8UU bearings around and 608ZZ bearings on the ends to allow smooth spinning.
I am going to put 1 small continuous GT2 belt to turn the cross carriage, and 4 long GT2 belts to pull on each side of the sliders.
Keep in mind, linear bearings don’t work on a spinning rod, they WANT to go straight.
They make bearings that allow spinning.
Just making sure you’re aware…and I’m not sure THOSE bearings start with LM
That works with a motor on each side, I’m using the shafts and pulleys to transfer motion to the other side. I guess the far side could slide, though
I will get it sorted, i have bearrings seperately defined, changing that part would be simple
So I spent some quality time with the ‘plotter’ tonight… @Shauki, did you have the ‘stiction’ issues when laying down plastic, or just running a pen around paper?
Most of my anomalies look like the pen is baing drug around the paper, or the paper isn’t flat to the build plate. It’s surprisingly difficult to get a large print to print all the way across the sheet…due to the paper not being tight, and the build plate not being 100% dialed in, and the pen will drift when a high-acceleration movement causes it to drag.
I guess I’m not ready to rule out Igus yet, the mehanism just ‘feels’ like it’s working as it should.
That said, I have had ‘squircles’ (Square Circles) at higher drawing speeds.)
From his posts it was on the prints.
