Page MenuHomeAleph Objects Inc

Confirm if going with single wiper pad or if scotch bright will be required
Closed, ResolvedPublic

Description

Current Alphas will have a single felt wiper pad. There was consideration of requiring a dual wiper with felt and scotch pad. We need to determine if we will need the scotch pad or not.

Event Timeline

Steven created this task.Nov 21 2018, 3:37 PM
Steven triaged this task as Normal priority.
Steven created this object with edit policy "LulzBot Hardware Products (Project)".

Here are some relevant tickets open: T2885 , T2904 and T3759

logan added a comment.Jan 2 2019, 1:12 PM

I have found the scotch brite works better if cut at double width and folded over so that the nozzle rubs on the outside of the folded edge rather than on the fraying edge

anolen added a comment.Jan 2 2019, 4:06 PM

@logan, which grade of scotch bright were you testing and do you have any pictures you could post to show what you mean?

logan added a comment.Jan 3 2019, 10:35 AM

@anolen The white stuff we were given, not sure on manufacturer's part number.
Here is a scotch pad cut to the same dimensions as the felt pad


Cut to double width:

Fold in half lengthwise and insert in wiper pad mount with crease facing up

logan added a comment.Jan 3 2019, 10:37 AM

Crease facing down was working OK as well, frayed a bit more but does great at cleaning the sides of the nozzle as well as the tip which is important during auto calibration as the side of the nozzle touches the cube.

@logan I chose not to load mine in that way because it shreds the pad pulling the nozzle along the closed web weave but if it works better that way it seems worth it. Only issue is the life of that pad, no objection from me. I did double up my pads tho so that the pad is a bit more dense, that could be part of the improvement for us both.

logan added a comment.Jan 3 2019, 11:00 AM

@anolen Yeah that would be about the same effect as inserting the double width with the crease down

@logan, Ill cut the next wiper pad batch I make to a double fold able width and have some passed around on Monday

logan added a comment.Jan 3 2019, 11:10 AM

Sounds good

logan added a comment.Jan 8 2019, 2:01 PM

I received a blue pad this week and installed it with the crease facing down as suggested. I have had a lot more probe fails since installation. Part of this may be because of the fold makes a channel that the nozzle tip lands in and may not be cleaning the tip as well.

oliver added a subscriber: oliver.Jan 8 2019, 2:09 PM

I can also confirm with @logan that the nozzle does not seem to be getting cleaned very well. I havn't had a probe fail but I have had some more inconsistencies with the probe.

@oliver and @logan you should have gotten PVA soaked wiper pads to test. Any thoughts on this?

@DaniAO I just noticed that I had some of the PVA soaked wiper pads under my printers bed. Testing them now.

I did noticed that If too much is used, it makes them a bit stiff and hard to actually fit into the current wiper pad mounts.

@oliver do you know which wiper mount you have? I do believe there is a new verison and it does make it easier to load the pad.

I am currently using one of the un-upgraded alphas. I was able to get it in and am aware that there is a new wiper pad.

Another thing to note is that we may want to consider a way to store them because the 2 I had were pretty stuck together, which could have been causing one fo them to be a bit stiffer.

Can I get some of the new wiper mounts? I still have the first alpha ones that hit the alpha blower shroud during the wipe

logan added a comment.EditedJan 25 2019, 10:07 AM

The pads seem better but still not always getting the end of the nozzle clean, and with only fractions of time available to pick/scrub those bits off before you can no longer reach or see the nozzle, I basically scrub the nozzle by hand before every print.
Q11 is back in pieces for OHAI so I wont have any further feedback for this until maybe mid next week.

yes.. I don't think we have a part number for it yet.. working on that now

The POLYDISSOLVE (pva didn't work) treated wiper pads going around now have been soaked in a solution that was too thick and thus the pads are harder to install (my bad), I am mixing a solution right now that should be thinner. Some of the pads may have not been completely dry when I sent them around and that is probably why you have found some stuck together (also, my bad). I will have a new round ready for y'all by Wednesday morning next week, along with the measurements of the ideal solution ratio. The pads are cut 25mm by 90mm, to be folded in half when installed. This measurement is for the newer wiper mount design so they will work best if updated.

Nozzle Heat test:

Original test, this polyester/abs wiper pad was pressed up against the nozzle at the writen temp for 5-7 seconds:

New Wiper Pad Tests UNTREATED, held against nozzle for 20 seconds:


100C


150C


170C


*This is the recommended wiping temp.


200C


*The black material you see is from the black Polyflex that was melting out the nozzle upon the heat up, not burnt pad.


220C


240C


*The material begins to melt at this temp.


260C


*This temp caused the wiper pad material to melt and adhere to the nozzle. There was no smoke or flame. There was a light burning hair odor. The material on the nozzle was easily wiped off.


@tutley and I set one of the white wiper pads on fire, it caught fire and degraded into ashy material. Combustibility seems only to occur when it is placed in contact with open flame.


I will be repeating all of this with a Polydissolve treated pad, coming soon.

DaniAO closed this task as Resolved.Feb 26 2019, 7:37 AM

We know we can't use the current wiper pad, and will need to use the white scotch brite pads. Going to close this ticket down as we have a few others open for that testing.