Prusa Mini Silicone Bed Leveling Mod  

RE: Prusa Mini Silicone Bed Leveling Mod

I think I'm good too, I'm too lazy to squish it further 😀

What would you say? Before / after  [why is it so hard to format your post?]

RE: Prusa Mini Silicone Bed Leveling Mod

@kormirluk

You have set the measuring scale rather roughly (+-2mm). Set it to +-0.2mm and level again. Then you can see the deviations more clearly.

RE: Prusa Mini Silicone Bed Leveling Mod

@karl-herbert 

Thank you for your input! I changed the scale and let it run a couple of time, these are my new values, even the github tool from bbenji says it won't get better somehow.

Or am I missing something again?

RE: Prusa Mini Silicone Bed Leveling Mod

I had not been using the visualizer.  Should I have 'Use Center Origin' checked in settings for the Mini?

RE: Prusa Mini Silicone Bed Leveling Mod

@kormirluk

I'm right at the point with you. i don't think i can make any smaller turns with my screw driver...

RE: Prusa Mini Silicone Bed Leveling Mod

@kormirluk

That is already very good. Everything within 0.05mm is perfectly adequate and provides a good starting point for printing 👍 .

RE: Prusa Mini Silicone Bed Leveling Mod

Anyone have leftover hardware / tubing that they'd like to sell? I'm in the US and about to do 2 Mini's and it seems like I have to buy way more material than I need.

-jim

RE: Prusa Mini Silicone Bed Leveling Mod

Posted by: @mcjamez

Anyone have leftover hardware / tubing that they'd like to sell? I'm in the US and about to do 2 Mini's and it seems like I have to buy way more material than I need.

 

-jim

I've got my tubing and lock nuts coming in at the end of this week. I can't find a source that will deliver faster than 2 weeks (OR, USA) for the Torx screws , however.  If you're able to source the screws, would you be up for doing a swap?

RE: Prusa Mini Silicone Bed Leveling Mod

@davem

i ordered a bag of a 100 screws for a tiny price, and have already done the mod. cover shipping and i got ya. can send 8, or a bunch. 

RE: Prusa Mini Silicone Bed Leveling Mod

Posted by: @arklan-uthoslin

@davem

i ordered a bag of a 100 screws for a tiny price, and have already done the mod. cover shipping and i got ya. can send 8, or a bunch. 

Thank you! I tried sending you a private message but am apparently too  new to do so yet. Could I bother you to send me a message so that I can reply with my address and get payment information for you?

If this mod works well for my 2 Mini's. I might package up the parts into a kit for future folks like me who want to get everything in one shot with tested components. 

-Jim

RE: Prusa Mini Silicone Bed Leveling Mod

@davem

Ha! I'm in the same boat, everything but the screws were mostly easy to find. Thanks for the offer though!

RE: Prusa Mini Silicone Bed Leveling Mod

@mcjamez

HMU if you end up making a kit. I'd be happy to add a note about that to the official Github repo for this mod.

RE: Prusa Mini Silicone Bed Leveling Mod

message sent.

RE: Prusa Mini Silicone Bed Leveling Mod

I finished my bed leveling mod and am supremely impressed at how well it works. It took me quite a while to tune it in. I didn't follow the online calculator as it expected one side to lift higher than the screws would allow. However, after figuring out how to tune it, I was able to get a really flat bed and performance is fantastic. I can print over the entire bed with zero issues now.

I've got enough hardware leftovers for 15 kits (using only 1 low profile 3mm locknut, the rest will be standard profile). I can't offer support but can offer the hardware including

9x M3-16mm Torx Screws

6" of silicon tube (about double what you need) 

7 M3 standard lock nuts

1 M3 low profile lock nuts

I can offer them for $6.00+ shipping in the U.S.A. 

PM me if interested.

-Jim 

RE: Prusa Mini Silicone Bed Leveling Mod

@mcjamez

Thanks for the feedback!

I am glad that the mod brings good results. It would be recommendable to integrate this into the mini from the beginning. After all, many other brands have this option.

RE: Prusa Mini Silicone Bed Leveling Mod

@mcjamez

Could you elaborate on the problems you had with the converter, please? The suggested adjustments are all based off the static center point. It should not have allowed for what I assume happened in your case. Any example MBL output would be nice too.

Glad we got you with a level bed though! It's nice to be able to print a perfect first layer anywhere on the bed.

Also, if you are interested, I can mention the extra kits you have available on the official repo. https://github.com/bbbenji/PMSBLM

RE: Prusa Mini Silicone Bed Leveling Mod

Posted by: @arklan-uthoslin

also, i swear to god, the mesh bed leveling on the machine doesn't do anything to compensate. like, the probe goes around and measures, but when printing, there's no compensation by the hotend. 

Hi,  @arklan-uthoslin I think you can see the auto adjusting working if you look at the top of the Z stepper motor. The threaded rod shows through and you can watch the flat part rotate slightly as the nozzle goes across the surface, thus compensating. Mine is not too good and I have ordered the parts to mod it. I also have a MK3S and did that mod and it made a big difference to print quality and to the "look" of the bed-side of the first layer. I have had a few problems with objects not staying fixed to the bed on the Mini (and, yes, I have done the z-calibration carefully and have almost "flat" calibration print, rather than the oval shape suggested is OK).

Roger

RE: Prusa Mini Silicone Bed Leveling Mod

Posted by: @benji

@mcjamez

Could you elaborate on the problems you had with the converter, please? The suggested adjustments are all based off the static center point. It should not have allowed for what I assume happened in your case. Any example MBL output would be nice too.

Glad we got you with a level bed though! It's nice to be able to print a perfect first layer anywhere on the bed.

Also, if you are interested, I can mention the extra kits you have available on the official repo. https://github.com/bbbenji/PMSBLM

The suggestions for the left side of my bed was asking for more CCW turns than my silicon spacers and screws were capable of making, I ran out of thread and "spring" to raise that side of the bed higher. So instead of going CCW on the left side screws, I went CW on the right side screws and re-probed. I know that given the fixed center reference, that shouldn't work, but it did. Once I got it close, the tool was once again useable and I used it for the final tweaks to near perfection. It's still not perfect, but wow is it massively better than it was in the beginning.

I'm also not convinced my X Axis arm is perpendicular to the Z Axis which could be causing some of my issues. I'd bet that I've compensated for that by tilting the bed to match. Hard to verify and it's printing so durn well that I don't want to touch it.

Feel free to send folks my way for a kit. Everybody should do this mod.

-Jim 

RE: Prusa Mini Silicone Bed Leveling Mod

@mcjamez

I see! It does indeed sound like your X-axis is not perpendicular to your bed. Aligning that should be the first step when doing this mod.  You might be able to see if the silicone tubing is more squished on one side compared to the other. It's possible and probable it is, but it shouldn't be too dramatic. If it is, it might cause some damage in the long run by applying too much stress to one side of the heatbed.

RE: Prusa Mini Silicone Bed Leveling Mod

@arklan-uthoslin

@sm26

@everyone 

Highly recommend you add a z-axis brace prior to performing the silicone mod to first correctly square the Z axis over the X.

The sure sign that you are not square is the constant downward slope of the bed across the X axis as shown in your screengrabs.

https://www.prusaprinters.org/prints/32054-prusa-mini-z-axis-support-brace

After a few tries, the brace flattened the X-Z slope and squared my X-Y at the same time which brought my z-deviations down from ±0.3 to ±0.1.

Now that it is square I will be performing the silicone mod to hopefully get it down to ±0.01.

I have ordered the following from mcmaster-carr and intend to report back how they work out: 

5041K732  Hi-Temp Silicone Rubber Tubing for Air&Water Durometer 70A, Opaque Black, 3 mm ID, 7 mm OD, 5 ft. Length

90236A123  Zinc-Plated Alloy Steel Torx Flat Head Screws, M3 x 0.5 Mm Thread Size, 16 Mm Long, Pack of 50