Replace the PEI sheet on the removable steel bed  

Re: Replace the PEI sheet on the removable steel bed

Some people do get extra steel plates to reduce/eliminate down time if/when something like that happens.

That said, yes, the PEI is replaceable; Prusa sells them, as do other sources (depending on where you are).
There are other discussion threads with tips on replacing them. You can find them via the advanced search facility (click on the little magnifying glass).

Re: Replace the PEI sheet on the removable steel bed

Thanks. Last I read someone said it was a right pain in the left ventricle (which is what I'd surmised based on the adhesive I mucked with). Getting a new plate from Prusa, though, is somewhat pricey shipping. I've a powder-coated plate from a third party in Canada that works beautifully, but I prefer the PEI for PLA. Maybe I'll see if there's a third party option. Or just play around with this damaged steel one and see what I can do with a combination of caustics and heat.

Re: Replace the PEI sheet on the removable steel bed

One of the issues I've had, of course, is that the Prusa seems to either forget its Live Z or alter it. I've had it scratch the bed on successive prints because it wants the Live Z to be once again adjusted upward .2 to .4 mm. It's maddening. I've wasted so much time on this thing.

Re: Replace the PEI sheet on the removable steel bed

One of the issues I've had, of course, is that the Prusa seems to either forget its Live Z or alter it. I've had it scratch the bed on successive prints because it wants the Live Z to be once again adjusted upward .2 to .4 mm. It's maddening. I've wasted so much time on this thing.
If you are using the same sheet and filament, the Prusa Mk3 should not be forgetting the Live-Z setting between prints. Adjustments of 0.2mm are extreme if no other hardware changes have been madeI calibrate mine perhaps monthly, usually when changing nozzles.

Is it possible there is something getting between the removable sheet and heated bed that throws your calibration off? Is the removable flex sheet laying flat and not snagged on the screws at the back?

Re: Replace the PEI sheet on the removable steel bed

If you are using the same sheet and filament, the Prusa Mk3 should not be forgetting the Live-Z setting between prints. Adjustments of 0.2mm are extreme if no other hardware changes have been madeI calibrate mine perhaps monthly, usually when changing nozzles.

Is it possible there is something getting between the removable sheet and heated bed that throws your calibration off? Is the removable flex sheet laying flat and not snagged on the screws at the back?

I always make sure I wipe down the bed before putting the PEI steel sheet back on just in case. Nothing's there. It's as flat as it gets. It's driving me crazy, really. Sometimes, even if I don't remove the sheet (just pull off the part), it does this. I'm two steps from chucking this printer out the window.

Alas, as usual, Prusa's support response on everything has been much along the lines of, "Hey... we have your money already. Enjoy."

I'm tempted to simply rebuild this with a different frame and new parts, but I've replaced almost half the parts on this already just trying to get it to print, and I've only had the thing for 3 weeks.

Re: Replace the PEI sheet on the removable steel bed

Have you checked to verify that the previous Live-Z persists across power-offs? Is it actually drifting or is something up mechanically?

Part of the fun with dealing with tech support is providing enough info to clearly indicate there's a problem. If you don't provide a good summary of the diagnostic steps you've completed, they are likely to assume you skipped something. In fairness, that's often the case. If you'd care to summarize the steps you've taken to troubleshoot this problem, folks here can chime in with some suggestions. If nothing else, you'll have more info to call tech support with.

Obvious things I'd suggest:

1. Document process of adjusting 1st layer. Take a pic. Note settings.
2. Power down. Repeat the process.

Keep it real simple, and don't allow for variables (e.g. changing filament or nozzle) between runs.

Good luck with it. It's a great printer once you get it working. Hopefully it's something simple.

Re: Replace the PEI sheet on the removable steel bed

Have you checked to verify that the previous Live-Z persists across power-offs? Is it actually drifting or is something up mechanically?

Part of the fun with dealing with tech support is providing enough info to clearly indicate there's a problem. If you don't provide a good summary of the diagnostic steps you've completed, they are likely to assume you skipped something. In fairness, that's often the case. If you'd care to summarize the steps you've taken to troubleshoot this problem, folks here can chime in with some suggestions. If nothing else, you'll have more info to call tech support with.

Obvious things I'd suggest:

1. Document process of adjusting 1st layer. Take a pic. Note settings.
2. Power down. Repeat the process.

Keep it real simple, and don't allow for variables (e.g. changing filament or nozzle) between runs.

Good luck with it. It's a great printer once you get it working. Hopefully it's something simple.

I just had to adjust again. Down from -0.267 to -0.145. I started at -0.985 with the first calibration yesterday. All PLA.

The ONLY thing I noticed is that the heat block seems like it may have shifted because of pressure from the heater cabling pushing on the side. But it's screwed in tightly (at 290C). It DOES, however, have an issue with the turning of the hot-end itself, but it's as tight in the PETG housing as I can possibly get it without gluing it into the housing itself (I don't know if PETG housing for the hot-end heat sink, relying solely on friction to hold things in place, is necessarily the sturdiest idea -- a screw-in housing would likely be a better design).

Re: Replace the PEI sheet on the removable steel bed

this might sound silly, but per heat before you print. see if that helps. I have had issues like this. and after making sure it wasn't my hot end. I am left with the science of preheat. but I am going out of my way not to change the live Z. at least my roll is semi new. but I swear to the gods, Skynet is messing with me.

Re: Replace the PEI sheet on the removable steel bed

Hi Neil,
If you look at the bottom of the extruder, is the heatsink level with the bottom of the extruder housing, like this?

or are the fins more like this?
[attachment=1]20180826_230941[1].jpg[/attachment]

(these are parts for my mk2.5 upgrade which are waiting to be used)

it the heatsink sticks out, it's because the top of the heatsink is not nestled into it's proper position

[attachment=0]20180826_231325[1].jpg[/attachment]
this picture shows the gap where the top of the heatsink, should be located.
the heatsink has not been inserted properly and will move about, changing live Z on successive prints

regards Joan

Re: Replace the PEI sheet on the removable steel bed

Heatsink is level with the base of the housing.

Re: Replace the PEI sheet on the removable steel bed

Alas, as usual, Prusa's support response on everything has been much along the lines of, "Hey... we have your money already. Enjoy."

haha, that seems familiar, I have similar experience with Support. I wonder how all those reviews over Youtube and makers websites promote this printer to a best 3D FDM printer on the market.

Re: Replace the PEI sheet on the removable steel bed

Everything I have read touts the support from the frum and not the phone or email route.

Re: Replace the PEI sheet on the removable steel bed

I generally use online chat, usually successful...

never used phone,

when online chat didn't work, I used email... took a while but it was successful...

regards Joan

Re: Replace the PEI sheet on the removable steel bed

Ditto on online chat.

Re: Replace the PEI sheet on the removable steel bed

I tried online chat. But once I mentioned that I am in contact with someone by email, they refused to continue discussing it

Re: Replace the PEI sheet on the removable steel bed

I tried online chat. But once I mentioned that I am in contact with someone by email, they refused to continue discussing it

I would not do that. I do not think they keep records of prior conversations.

Re: Replace the PEI sheet on the removable steel bed

I would not do that. I do not think they keep records of prior conversations.

Well now I know. I am pretty much desperate. Email support does not provide any solution, chat takes too much time, looks I'm on my own. Being on my own for this money is ... priceless