bed level change

[PcS]

idea.jpg (112.72 KiB) Viewed 9865 times

I ordered some parts to thumb wheel the bed on my M2 today. This is what I have in mind . The springs are longer and considerably stiffer. My screws are always too loose when the bed is properly leveled . I read all the other threads about loctite and different spring pads. I am hoping to get a spring with enough tension so it does not move. And the studs are longer to allow more adjustment. If that doesnt work i will use nuts above the thumb wheels and lock it for good !!! Thoughts ? Ideas ? Open for suggestions !

[ednisley]

a spring with enough tension so it does not move

The trouble with springs: they provide no damping at all and allow the platform to vibrate. If "does not move" is the objective, replace the springs with rubber pads, adjust the platform to slightly compress the pads, and be done with it.

Works for me, anyhow:
http://softsolder.com/2013/05/31/makerg ... ilization/



I think the main benefit of a spring-mounted platform is to reduce the (potential) damage from a nozzle crash: the platform will move as the nozzle presses on it. The silicone rubber pads have barely enough compliance to align the platform, so, if you expect nozzle crashes, they're probably not the right hammer for the job.

[PcS]

Thanks for the input. Never had a nozzle crash...with the bed at least. Lol I got springs with a compressed force of 19 lbs. I am hoping that will be enough to keep them from moving on their own. I considered your solution a while back. I am glad it has worked well for you. And will keep it in mind if this fails lol

[LazMech]

Yea, compression springs don't have built in dampening so if you print at high speeds and low layer height I could imagine it would contribute to a poor finish quality.

Mcmaster has some "shock absorbing" springs (link below); never used them and the ones mcmaster has seem pretty big but maybe smaller ones are available somewhere else. The temp range is low but could always use a PTFE washer as a conductive heat break.

http://www.mcmaster.com/#compression-springs/=xtoibv

Or you could design your own dampening spring and print it with ninjaflex.

[PcS]

I took the plunge and made this change with the springs . In the end I think I will do away with them and and lock the bed firm. I typically print on the slower side and full bed size and tall. I typically have to re level the bed after one of these long 53 hr prints. The springs are not so much for dampening in my opinion as they are for ease of adjustment. I see more motion from the z rods on wall infills.As always I could slow down more to compensate. I am looking for a happy medium though. My m2s bed screws always had to be backed out quite a bit to level the bed. I think the z rods might need to be realigned a tad. Maybe from shipping. But now with 1/4 -28 ss studs 1.25 long I can set it and forget it . Hopefully !

[jimc]

the z rods have an adjustment at the bottom. they go through a larger hole in the frame then the clamp at the bottom locks the rods then bolts to the frame. fairly easy to adjust the alignment.

btw, a long time ago i think you were talking about making that triangle plate that the springs and bed screws go through out of a thicker material. did you ever do that?

[PcS]

I have it modeled, but never had it made. I knew I could adjust the z rods just never took the time to do it .Flipping my triangle plate over helped a little. I need to replace my y slide now she is getting loose.