The ends curl up on first layer  

RE: The ends curl up on first layer

Looks like you need live Z adjust.

RE: The ends curl up on first layer

Dirty bed - soap and water are your friend.

If you have doubts: this is a bed fresh and cleaned using ounces of alcohol: one soap and water wash made prints stick like tape.

RE: The ends curl up on first layer

(Tim does not actually mean fat-based soap)

RE: The ends curl up on first layer

Or do I ???  lol   

The net effect is the same using detergent or soap; and generally the label is interchangeable in the cleaning trades. Heck, they call Lithium Grease a soap based product, too.  Soap being a combination of agents to keep things in solution.  Soap is one of those words that make English fun for non-native speakers, akin to to, too, and two, which doesn't add up to six. 

ps: Robert is correct.  The common thought is Dawn or Fairy dish washing liquid is best for the task, and is a detergent.

RE: The ends curl up on first layer

I always take a risk, correcting my Elders - but I do preach the gospel of Dawn.

RE: The ends curl up on first layer

had the same problem i used glue to fix the problem 

RE: The ends curl up on first layer

Posted by: @cameron-reuter

had the same problem i used glue to fix the problem 

And some people use sand paper.  Why people won't simply use soap and water to fix a dirty bed problem amazes me.

RE: The ends curl up on first layer

Unfortunately in my country there is no specific product branded "Fairy" or "Dawn", are there any parameters I should look for or avoid in dish soap? Like with or without certain additives. I am sure we have products like that, it just may be harder to find given they have oftentimes "improved formula" compared to what they used to be. Add in different scents and skin protection additives and it gets confusing. 

RE: The ends curl up on first layer

Ordinary plain unscented unadulterated dish soap/detergent - though unscented is getting harder to find.  You really don't want the liquid soaps that have hand sanitizers, hand lotions, and other additives that tend to leave residue that counteracts cleaning.  So no disk sponges, no dish clothes, just use plain new paper towels as a scrubber and to dry.   

note: Some people do use a new plain sponge with a scrubber pad attached - but they have been picked carefully to not be true abrasive pads, and are never used for anything but cleaning coated sheets.

Here's a website to find local brands: https://smartlabel.pg.com/00037000973850.html#ingredients

Here's an alternative: https://www.seventhgeneration.com/dish-liquid-free-clear

RE: The ends curl up on first layer

As a postscript to all this: I've been there - that level of frustration with PLA not sticking to where I wanted to sand blast the sheet to make plastic stick to it.  Alcohol only made things worse; so I went through a quart of 91%; then tried 99%; again, nothing.  Somewhere on here, someone mentioned soap and water.  So before I went the sandpaper route (I was moments away from it) I took the sheet to the sink, believing it wouldn't make any difference, after all, alcohol dissolves everything, right? 

Well - it was a hard learned lesson - I now use soap and water.  I do use acetone once in a while, every couple of weeks after heavy printing. It removes the PETG and PLA residuals best - those shadows of the last print you get that don't wash off with water.

For me, using alcohol is a total waste of time.  Others find it works for them, but I wonder just how much better their adhesion would be if they tried the sink test.

RE: The ends curl up on first layer

@tim-m30

Thanks, I have found local brands that were taken over by P&G and packaging looks very similar to Fairy in UK. 

RE: The ends curl up on first layer

Most of the "soaps" have a lot of things inside, but what they always do is removing the fat. So I wash it with a soap of any kind, then dry it with paper towels and finally I use IPA to remove the residual things that might remain from soap. That is like once per month. For each and every print IPA is good enough, if the plate is not too greasy. It is truth, that the removable plates make this a bit worse. On the old fixed plates you usually used spatula to remove anything, not so much touching the surface. Now you take a metal sheet with your hands and bend it to remove the prints. So there is more often the contact with your fingers.

Also do not forget on one good procedure with PEI sheets. From time to time "brush" it with the kitchen sponge (the coarse side), it will renewal the structure of the PEI. Sure clean it after that with IPA.

Milos

RE: The ends curl up on first layer

Alcohol after soap and water just recontaminates the bed and wastes time and effort and reduces stickiness.

Alcohol wets the paper towel, sucks oils off your fingers, then as you wipe the bed you leave a film of new oil.  Unless you wear gloves or had a wad of paper towels thick enough the alcohol never gets to you fingers.  But that would be many towels.

RE: The ends curl up on first layer

There is much more chance that you will contamine the plate after washing by drying or moving it back on the bed. So if I take a piece of paper towel, aply IPA and finally clean the plate already on the bed, I doubt that the fat from fingers will go through the towel to the opposite side and contamine plate again in 5 seconds. I have a good results with IPA before each print with occassional (ones per month) washing.

RE: The ends curl up on first layer

Posted by: @milo-v

I doubt that the fat from fingers will go through the towel to the opposite side and contamine plate again in 5 seconds. I have a good results with IPA before each print with occassional (ones per month) washing.

I have lots of personal experience with alcohol doing exactly that.  It likely depends on the person.  When I was 25 my hands were fairly dry and fingerprints were never a problem: holding the leads of an ohm meter I read meg ohms.  At 60+ my hands are a bit more productive, I read kohms, and it is pretty amazing to see the oil film I leave (a streak test makes it pretty obvious).  

Streak test: when contamination is suspected

• With a fresh piece of paper towel, and gloves, dampen the towel with 91%+ alcohol, and wipe the bed side to side moving back to front, like you're painting it with alcohol. The alcohol should be thin enough on the towel it quickly evaporates from the bed. If you see any streaks, the bed is dirty and needs a wash.

RE: The ends curl up on first layer

@damonso

I always print my first layer slow due to difficulties with petg.

Speed 20mm/s and i think it now the prusa standard.

And acceleration on first layer down to 300. It is usefull when the nozzle do some u-turn like your case or near 180°. I had good results to print sharp parts with that value and now i keep it for all.

RE: The ends curl up on first layer

Hi Tim, I would not agree, but it seems to be an interesting topic. Maybe we can measure by the resistance and see. I would not link the fat on the fingers directly to the age. I think it much more copies what you just did before. After dinner it is usually worse, especially if I had something tasty 😉 But it is worthy to check.

I use 99,9% Isopropyl Alcohol, maybe it is a bit better then yours 91%.

Still I think that just wiping the steel sheet very fast with paper towel with 99.9% IPA is much saver then moving the steel sheet in your hands after the soap wash back to the bed.

Milos

RE: The ends curl up on first layer

Hey Milo,

I used to work (engineering) around 10kV stuff that hurt when it reached out and touched you, and 600V stuff that reached out to kill you. So my body responded by drying out, literally. And yeah, I've been knocked across the room by silly designs (no bleeders on power supplies - which I quickly fixed).  But my skin resistance changed while I was working in CRT manufacturing engineering, I failed every county fair love test I tried - lol; later it dropped back to normal, but it took a while. 

The alcohol thing is purely a matter of dilution. A quart of alcohol cannot dilute oils as well as 5 gallons of soapy water, and when we are talking about a dram of alcohol, there is no contest.  For alcohol soaking up oil off fingers, I've done tests and it is a lot worse than a person would think.  A finger print is 50 ug, but alcohol can wick the entire finger load of oils, everything between the ridges, into the paper towel in seconds; which then spreads to the bed as you wipe. The alcohol evaporates and leaves a nice invisible film.  It takes a streak test to expose it.

In the end, care and proper handling minimizes to transfer, but the risk is large enough to recommend folk avoid the practice if they are already having adhesion issues.  The best method for alcohol that I've seen is to spritz the bed and wipe with a rather large lint free towel, but even then the next time you clean, which part of the towel touches the bed, is it by chance the place where you grabbed the towel last time? Instead of a fingerprint, now you have a full hand print to deal with.

As for handling after a wash, it's rather easy to only handle the sheet by the edges. And when grip is needed, only use the non-printable area in the front. After a couple washes it's a natural and easy process.

RE: The ends curl up on first layer

I have printed with materials that were tremendously hard to get to stick to the build plate. I was pulling my hair out (seriously I have no more hair). What fixed it was I cleaned off the build plate like normal then just sprayed on a layer of hairspray. I thought hairspray was widely known, but I haven't heard about it recently and keep seeing everyone mention glue, acetone, sandpaper, etc. Hairspray works wonders.