Carbon Fiber arms from Trick Laser

[cambo3d]

http://forum.seemecnc.com/viewtopic.php ... 053#p11053

[626Pilot]

I read somewhere that someone measured his arms and found them to be a fraction of a millimeter shorter than stock, but I forgot where. Has anyone tried measuring? I'm seeing tall parts flare outward and it seems like that might happen if the length was off just a little. I'm not sure how to get an accurate measurement since it should be from center to center of the connectors on either end.

[Navkram]

my understanding they are build on a fixture held center line to center line so I don't know how they could be short. but anything is possible, e-mail them directly I am sure they can help. http://tricklaser.com/contactus.sc

[Eaglezsoar]

One of my arms has developed a squeak after about a week's worth of runtime. Is there any kind of grease I can use to fix it?

A white lithium grease, a small amount, can be used on the joints. Sorry about being late in answering. I just spotted your message.

[Flateric]

I read somewhere that someone measured his arms and found them to be a fraction of a millimeter shorter than stock, but I forgot where. Has anyone tried measuring? I'm seeing tall parts flare outward and it seems like that might happen if the length was off just a little. I'm not sure how to get an accurate measurement since it should be from center to center of the connectors on either end.

Mine are smack dab, laser perfect exactly the same length as each other and the stockers.

[lordbinky]

The delta rod length in the firmware determines your X/Y scaling of your print. If I'm thinking right (which I may not be) then being off from the firmware's rod length by 1mm only changes your print's size by ~1.4% which for me is less than ABS shrinkage. Even then you can change/correct that in firmware, what you can't change and is more noticeable to print quality because it isn't consistent is having differing arm lengths.

tldr; Equal arm lengths are more important to prints than the "correct" arm length in the firmware.

[626Pilot]

I tried to print the owl everyone does (first really tall thing I've tried) and the print kept failing at a certain height. I tried a few different arm length settings. Stock it was 269mm. Making this shorter (268) made the print fail slightly sooner. 270 was better but it still failed. The sweet spot seems to be 271. I made a 250mm calibration cylinder and it printed all the way up. Before that I noticed some of my prints over a few inches in height seemed to flare out as they got taller, but the cylinder seems to have printed straight. It seems to me that we calibrate our printers to be perfect at zero height, so the arms can be the "wrong length" and it will be fine at the surface, but keep incurring error as you get further away from the surface to the point that it just won't print anything over a certain height.