Painters blue tape and calibration  

RE: Painters blue tape and calibration

Hi John,

Yes, there is an option in the Slicer to add an offset. Are you using PrusaSlicer?

Anyway before you can set it, you will need to know this offset. So you will need to adjust your live-z. Just make sure writing down your old value, so you can go back very easily. I would recommend to raise it by 0.1-0.2 before starting the print and then adjust it during the print.

For Nylon I had not much success with blue tape. It warps a lot and pulls up the blue tape. Better is to print on PEI sheet with glue stick.

Flex works perfectly fine with blue tape. I'm printing FLEX only on blue tape once I saw the result. Nice side effect is slightly rough surface finish.

RE: Painters blue tape and calibration

Thanks nicholai

do you put the blue tape over the whole bed or just the portion being printed. 

RE: Painters blue tape and calibration

Remember how the height sensing works. The PINDA senses the spring steel sheet in the middle of the print surface. Because just about everyone's Live-Z is negative, it appears that Prusa then over estimates the height of the bed to protect the bed and nozzle from a collision at the beginning of calibration when the Live-Z value is zero. Then you use the Live-Z to adjust for where the actual surface is during calibration. So by adding a layer of tape to the PEI surface, the Live-Z needs to be higher to get the same first layer thickness. No, painter's tape isn't very thick, but neither is the first layer. The datasheet from 3M for the Scotch-Blue #2090 gives a tape thickness of 5.4mils (this is total thickness, so it should be both the tape material and the adhesive thickness). Converting to mm, that is 0.13716 which is 68.58% of a 0.2mm first layer thickness. If I was using that specific tape, I would move my Live-Z up by 0.13716 as my first approximation. If I was using a different make and/or model of tape I would either find the datasheet or measure it with my calipers.

I suppose you could, instead of adjusting Live-Z, add the correction value to the slicer. If doing that I would only put the tape where I expect to be printing. The slicer z correction only happens after the purge line. If adjusting the Live-Z, I would put tape both where I expect to print and at the purge line.

As far as covering the entire bed, that is probably a waste of tape. You will probably want to cover a little more than the contact area for the print. This should (hopefully) do two things:

1. If you guess wrong where your print is, it is more likely to hit a larger area than a smaller area.
2. It may act a little like a raft to keep from peeling up between the tape and the print-bed.

RE: Painters blue tape and calibration

Posted by: john.h68

do you put the blue tape over the whole bed or just the portion being printed. 

Only the part where I print. No need to waste a tape.

RE: Painters blue tape and calibration

Thanks both of you - I've almost finished my dry box and PTFE arriving today - so I expect I see how it goes soon.

RE: Painters blue tape and calibration

Hello,

my advice is to pay attention to blue tape 🙄 . Mine adhere incredibly, and on the other printer I have, I have to apply a big force to remove it from the glass. That means that there is the risk that:

• It creates bubbles on the adhesive PEI sheet by detaching it from the metal or even worse breaking it...
• It leaves glue residues on the PEI (and you can't use all sort of solvents on it how you can do on glass. You can use only IPA on PEI to clean it without damages, it should be enough, but I found several tape glues that did not removed completely from the glass without string solvents)

Perhaps using an old damaged Chinese PEI metal sheet may be a better solution.

And last but not least, do not use the tape on the textured powder coated PEI sheet. 😎 

Regards

RE: Painters blue tape and calibration

Rather than gunking up a poor hapless and expensive PEI sheet, I suggest looking into a bare spring steel sheet and doing the deed to it. I purchased a couple of the $20 bare sheets from PrintedSolid, and have applied textured vinyl, blue tape and other oddball surfaces. This keeps my good PEI sheets clean and seasoned for PLA or PETG (one surface each) and try out whatever other nonsense strikes my fancy on the lab rats.

You can always try the cheaper ones from AliExpress, but I find the PrintedSolid much springier and only a couple of bucks more. I like supporting companies that are truly involved with the 3D printing community whenever possible.

RE: Painters blue tape and calibration

 I did see Gecko Tek EZ-Stik with a plain reverse side. https://www.printedsolid.com/apps/omega-search/?q=sheet#q=Gecko&p=1

Any thoughts especially as I plan to use nylon later. 

One thing that I noticed was the surface was good for 100 prints which didn’t seem a lot.

RE: Painters blue tape and calibration

Interesting. I thought the painters tape was low tack. 

RE: Painters blue tape and calibration

Too late to edit

here is a FAQ on geckotek

https://www.geckotek.co/apps/help-center#!what-setting-do-i-use-with-ez-stik

RE: Painters blue tape and calibration

Shoot printedsolid don’t ship to Australia.  It I did find the geckotek sheet on amazon. Does anyone know if you can buy the spring sheet form amazon?

RE: Painters blue tape and calibration

Posted by: john.h68

Shoot printedsolid don’t ship to Australia.  It I did find the geckotek sheet on amazon. Does anyone know if you can buy the spring sheet form amazon?

You can search for "Mk3 spring steel" and see many of the knock-offs. Those same sheets are 1/2 the price from AliExpress if you don't mind the wait. They are definitely thicker sheets compared to the Prusa and PrintedSolid. Charles here on the Prusa forums has done comparisons and seems to have had good luck with the FYSETC sheets.