Printable Front Bed Stabilizer - Level 1 Novice

The stabilizers seemed to be helping on my test print last night until it got to ~125mm on the Z. Then it started having little layer offsets where the rollers must have hit some debris on the side rails. The offset was slight but very noticeable on the smooth walls of the print. I will try to post a picture at some point. Just for good measure I ran the print twice and got the same result twice. Luckily, to take the stabilizers out of service, I just undo one screw on the spring and move the plungers inwards. 

Results so far have been mixed. If someone has some extra time and wants to play with this then have fun. If nothing else, I have a good base for a printable roller limit switch.

2n2r5,

Nice idea!  I think perhaps why you are getting mixed results may be due to the fact that these still create a "floating" system being that both ends are spring-loaded.  Perhaps if you immobilized one side to ride hard on one rail, while the other side remained spring-loaded to compensate and always bias the bed to the other side.  Of course, you would need to find out which rail is more dead parallel to the z-axis, but it's worth a shot.

If you attach a dial indicator on both sides of your bed and sweep the steel frame from top to bottom you would find they are probably not perfectly parallel with the Z axis rails. Those rollers are going to follow the angle of the frame and not the rails, which introduces a slight push factor in one direction or another via the force of the springs. Might be doing more harm than it prevents.

Yeah, that is the conclusion that I ended up with too. I have equal forces pushing on each side of the bed working to cancel each other out. The friction in the plungers might actually be helping a bit. Probably not enough to make it noticeable. I don't have any real issues so even if this did help, I would have a hard time seeing any evidence of it.  I think a shock absorber would work better than a spring but really, I only messed with this cause I was bored. I don't think that this will help enough to make it worth the trouble. The best thing would be a new bed all together that has supports wider apart and at all 4 corners. That falls under the realm of might as well build a new printer.

I think the important thing isn't if the side rail is straight so much as it is straight to the eye. I am wanting only to get an esthetic print. When I look at the side rails, I would be delighted to get something as straight as them. If you have a bent angle support then putting some flat stock on on the inside of each rail should cure that. I really don't think the 3/8" guide rods are significantly out of parallel with the sides of the printers. Or at least it didn't show up in my test prints. I would be interested to see it  measured though.

I had looked at making something like the (CRAPPY) picture below.  2 more vertical drill rods going from the current Y belt brackets down to some new (not yet created) printed drill rod holders and 2 printed parts to go from the bed frame to the drill rod and ride on linear bearings.  I figured this would sure up the movement but being that you can flex the drill rod a bit it would let it  move enough.  The problem i saw with riding on the frame as rails is its not always the same distance to the rails all the way down the standard drill rod.  and if you mount on springs like done above you are letting it walk where ever it wants.  I have not had time to design the parts at all but I dont think it would be hard.  I have the SD3 with the aluminum bed frame and if i had the measurements with me i would just whip it up real quick...but im out of town on business and wont be around my printer for a week.  I also wanted to add that it shouldnt effect the vertical travel is designed right as the frame height would be sufficient thickness for the arms.  the the print head should be ok also.