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Wiper pads change
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After some testing, it has been brought up that the current wiper pads do not work well with Banded and Dingy. As the pads break down, the fibers stick inside the large nozzle, and interferes with the probing process.

It has also been brought up that the current supplier may not be able to continue to supply our wiper pads. We may have a second source who can make them, but something to think of now is do we want to consider changing the entire wiper pad for all printers and tool heads, or stick with what we have and included a different wiper pad with Banded and Dingy.

@anolen @adam @tutley @west @nickp @karrad @Steven @samantha @kent @david.hall @jessica
Would like all of your input on this.

@lansky do we hear about probing issues with the MOARsturder? is this something we should think about rolling in to that tool head as well if we don't change the printers?

Event Timeline

DaniAO created this task.Sep 24 2018, 1:49 PM
DaniAO triaged this task as High priority.
DaniAO created this object with edit policy "LulzBot Hardware Products (Project)".
west added a comment.Sep 24 2018, 2:06 PM

@DaniAO for quiver, we could use new wiper pads. The current set up is an abrasive wipe and a polishing wipe. We can switch either accordingly

anolen added a comment.EditedSep 24 2018, 2:07 PM

**Actually the fibers are not sticking inside the nozzle, they are adhering to the outside of the nozzle which has more surface area the larger the nozzle is, making it statistically more likely that a fiber would remain.

I have been using the Scotch Brite 3M #7447 scrubber pads in place of a wiper pad for my banded and dingy testing. It has been FAR more reliable that the normal wiper pads. I feel this is due to the fact that the 3M pads are pressed together with larger strands of fiber and the normal wiper pads are shorter fibers making it easier to separate from the pad and adhere to the nozzle. I do not believe more coating of ABS will make much of a difference long term.

My only concern is increasing the pads abrasiveness may cause the life of the copper nozzles to decline. I feel more testing is needed before we can determine this for sure but my current vote is a YES for switching all wiper pads over to the #7447.
(of course... we could just switch all nozzles over to being hardened steal... any takers?)

adam added a comment.Sep 24 2018, 2:15 PM

I have the same concerns as @anolen. I want to know how much this might reduce the life of our standard nozzles before we go for full replacement.
I think including a replacement wiper pad in Banded and Dingy of the 7447 scrubber is both doable and advisable.

Previous testing was none in Cluster to see if the Scotch Brite pads would work well for replacing the wiping pad. We found that the green pads would wear the nozzles too rapidly, but the Maroon 7447 pad would work well for cleaning without being too abrasive and shortening the life of the nozzle too much. The hardened steel nozzles would not be affected (much), but we would want to see what type of longevity that we have with the brass nozzles. Perhaps we could install them on a pod in Cluster and remove them after 2 weeks and see what the wear is on them. This may give us an idea of how long they may last. Of course, as @anolen says, we could just switch all of our nozzles to hardened steel!

@anolen agreed. My only concern about using scotch brite is the reduced lifetime of the nozzle, especially since we dont support people changing them out.

@adam i am all for switching all of our nozzles to hardened steel

E3D asked this morning if we are considering changing all nozzles to hardened steel. If there is a consensus that this should happen, lets get another ticket going on this! @DaniAO

@jessica how much does that change the cost?

@anolen that means testing on all the profiles on all the tool heads with the E3D hotends.

We don't see more probing issues on the Moarstruder compare to any other toolhead, if anything it's more reliable.

@lansky The higher reliability of the Moarstruder could mean that there is a difference between the metals of the nozzle, the nickel/copper may not attract the fibers to the same degree. I am going to dig into some research here and let ya'll know.
@DaniAO Yeah it would mean a lot of confirmation testing, I feel the biggest change would come at the "Regular fan Speed at Height" because it was the blow back of the fan at a lower height as it hit the bed, that caused my temp drop issues. More discussion about this?

adam added a comment.Sep 25 2018, 8:44 AM

How quickly are these other pads getting gummed up with the filament remains they are removing from the nozzles? Are we able to pick out filament like we have before? Are customers going to go through a lot more, a lot less, or about the same amount of these?

I feel it would be about the same but I have not been documenting my use with these since my focus has been on profile development, I would feel more comfortable implementing some testing that is designed to document this info and work from that.

After some discussion about this with @anolen ,i dont think the moarstruder is actually getting more reliable probes. What i think is happening is people arent noticing inconsistencies with the first layer as much because of the amount of material being deposited. The moarstruder prints will have a big fat bead for the first layer and seeing leveling inconsistencies in it will be hard to pick out. Go to a smaller nozzle like on cecropia or especially achemon and immediately the leveling inconsistencies will become more apparent.

Yeah, I did some research but couldn't find any evidence to suggest the different metals have any effect. The wider margin for error with a thicker bead may be a strong influence in this data, should we investigate further?
I am wondering how big of a drawback it is to make these changes, what are we possibly loosing by changing the wiper pad and/or the nozzle metal? (time, resources, etc.)

@anolen I have a bag full of test wiper pads. One bag is treated twice with ABS. Second bag is treated three times with ABS. Would you like a few for testing?

We did find the test wiper pads that Brent had sent over a while ago that have a light side and dark side.

Light side is recommended to be used with PET, PETG, Nylon, PVA, and PLA. The Dark side is recommended to be used with ABS, TPU, and PLA. @anolen has a handful to test on her machines.

Hey all! I wanted to chime in and see if I can be of any help. My understanding of it is that the sharper nozzle section of the E3D nozzles (especially the smaller nozzle sizes) is causing the nozzle to sink into the pad farther during the wipe and is just generally better at breaking up the ABS/felt matrix. I Agree with @tutley and @anolen that the MOARstruder is likely just better at hiding the inconsistencies due to the wider and taller bead, but the gentler slope of the nozzle might be playing a part.

So far I've delivered 3 types of modified wiper pad for testing:

  • Material treated with the same ABS/acetone blend in 2 separate applications (allowed to dry between applications)
  • Material treated with the same ABS/acetone blend in 2 separate applications (allowed to dry between applications)
  • Material treated with the same ABS/acetone blend on one side and with PVA glue used as the binder on the other side

The 2 types with extra ABS/Acetone treatment were intended to make the pads last longer and the version with one side treated with PVA was intended to work better with materials that don't adhere to the ABS style pad (mainly PVA and PETG)

Please let me know if there's anything I can do to help out with this process.

Cheers
-Brent

DaniAO added a comment.Oct 8 2018, 7:36 AM

@anolen How is your testing going on the other wiper pads?

Hey all! I'll be up at AM on Friday this week dropping off a batch of wiper pads, if anyone has time I'd be interested in getting together to answer any questions and try to find a better solution going forward.

@coloradoprintingproject what time do you expect to be at AM?

I was planning on early afternoon, but if there's a time that would work best for you all let me know and I'll make it happen.

That works, see you then.

Cool, is 1pm tomorrow good for everyone?

i wont be here :/ we have EMI testing, and then josh's wedding

@coloradoprintingproject We have meeting scheduled at 1pm, can you do noon or 2?

Updates on wiper pad testing data can be found here: T2885 and T2904

mbloom added a subscriber: mbloom.Mar 31 2019, 1:05 PM

I did some research over the weekend, and found a thingiverse page where someone described how they're making their own wiper pads. They're using .25 inch polyester felt, Mcmaster part# 88085K311, cutting them to length, then soaking both sides in Lulzjuice (abs dissolved in acetone). He said thiat this process was documented in the "Lulzbot whitepapers" if anyone knows what thoes are. I think this is exactly what we've been using. Links below;

Thingiverse page;

https://www.thingiverse.com/thing:2843561

Mcmaster part# 88085K311 (Search for the number);

https://www.mcmaster.com/catalog/125/3666

kent added a comment.Apr 1 2019, 7:22 AM

this process was documented in the "Lulzbot whitepapers" if anyone knows what thoes are.

http://devel.lulzbot.com/wiper_pads/wiper_pad_manufacture_SOP.odt is probably what they are talking about.

DaniAO reassigned this task from DaniAO to adam.Jun 3 2019, 3:27 PM

Reassigning this to Adam as he was working on wiper pads.

anolen removed a subscriber: anolen.Jun 24 2019, 11:27 AM