Spring steel sheet

Hi,
I'm mainly printing PETG (99% of the time). Until now, I've been printing on blue tape, then mirrors + hairspray. My last 2 mirrors broke while printing, within 24 hours ! Back to blue tape...
I'm considering spring steel sheet.
I'm not interested in textured PEI coating, I want a smooth 1st layer, and the same results I'm used to get with mirrors.

3 reasons I'd like spring steel sheet, no coating :
- smooth surface
- experimenting with inductive ABL probe (I've been using a BL Touch since the begining)
- experimenting with the nozzle as a probe against a conductive surface

Before I order :

All magnetic beds come with PEI. It seems they don't last long with PET(G).
How to 100% remove PEI coating ? It seems ethanol methanol and chloroform can do it (I have all of them).
Does spring steel + hairspray work like glass + hairspray ?

With PEI and PETG the secret is to have a relatively high Z offset for the first layer. I use an offset of 0.08mm higher for PETG than I use for PLA, and I could probably do a whole 0.1mm and the PETG would still stick well enough. You essentially want no "squish" on the first layer.
That said, you can buy the spring steel sheets with no PEI: [www.aliexpress.com]

This is exactly what I need. But for this item, I will purchase from Amazon with Prime because I had poor experience from Ali with large items : damaged parcels. (I purchase a lot from Aliexpress). Where I live, Energetic 3D SSS are not available from Amazon stock ; they come from China..

It is unclear what SSS are single or double coated. I even searched for negative comments from customers receiving single coated SSS while expecting double coated. No success ! It seems Two Trees SSS are single sided. If I understand correctly, powder coated SSS are textured, and adhesive PEI is smooth ? (I don't want any texture).

I never squish 1st layer with PETG : squished 1st layer is the best way for nozzle build up and ruined parts ! 0.1 to 0.2mm, plus underextrusion (usually 95%) on glass + hairspray. I love PETG and rarely print PLA (I only print structural parts). If I understand correctly, PETG sticks to PEI as hell, and some hairspray or PVA glue is needed as a release agent. Just another reason why I want to test bare stainless + hairspray...

Edited 1 time(s). Last edit at 10/10/2021 05:20PM by yet-another-average-joe.

I just received the Two Trees SSS : exactly what I needed ; one side coated with smooth PEI, the other being bare metal. 310x310mm, perfect fit for the Tevo Tornado (the bed is 310mm wide).

I print largish PETG items on PEI all the time. I use 70C bed. The prints stick, but come off easily enough by applying a few drops of IPA to the bed/print interface prior to prying them up.
I use this type of tool to do the print release:



I never liked either glass or hairspray...

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]