Cold Shock Damaging to Satin Powder Coated Sheet
I've been using the Satin Powder Metal-Coated Sheet for a few months now. It has become a common practice for me to pull the sheet off the heat bed after a print and set the sheet, with the printed part on a marble counter-top. The heat sink of the counter drops the temp quickly and allows me to pull my part off, take off the other artifacts from printing, and reinstall it back on the printer and be ready to print again in just a few minutes. A friend who is an engineer was by today and observed me doing this and told me that he thought that would cause the metal coating to degrade faster than allowing it to cool slowly. Anyone out there have any experience with cooling the print this way, and had any adverse effects to the Sheet?
RE: Cold Shock Damaging to Satin Powder Coated Sheet
I do it the same way. You have to hold in mind, that these sheets are consumable materials, but they last long.
Best regards, Clemens
Mini, i3 MK2.5S, i3 MK4, CClone (Eigenbau)
RE: Cold Shock Damaging to Satin Powder Coated Sheet
That makes sense. Thanks Clemens.
RE: Cold Shock Damaging to Satin Powder Coated Sheet
Do I raise my standing if I say I'm an engineer? I have extensive experience & education in metals & metal processing, but not specifically polymer bonding on metal. I have had satin sheets on both of my printers for only a few months. I have been setting the satin sheet from the Mini into a granite cutting board, much as you have. I don't think the temperature gradient is deep enough or rapid enough to degrade the bond. It's not in the range of what I would consider to be "thermal shock". Neither material is going through a phase change or crystal structure transition in this temperature range. There is thermal expansion & contraction, but neither of these materials is brittle enough to cause stress fractures in this range or speed of contraction. Maybe if it started at a higher temperature than the heated bed is capable, & then quenched in ice-cold liquid, there might be a problem.
Whatever you find to do with your hands, do with all your might!
RE: Cold Shock Damaging to Satin Powder Coated Sheet
Another consideration would be the thermal expansion coefficients of the two materials and the bond between them. During temperature change, the coating must be able to expand with the metal plate and not break or weaken these bonds. The faster the temperature change, especially in the cooling direction, the larger the stress would be. There is a lot of advice out there to allow the plate to cool naturally before removing the print, I've always thought that was to prevent deformation of the plastic, but who knows maybe print surface failure is also a motivation.
RE: Cold Shock Damaging to Satin Powder Coated Sheet
Good input burtronix, ty. You sound as much like an engineer as some I've worked with in the past.
Did I mention the engineer is my son-in-law. I try to walk the fine line of being appropriately abusive, but not too hard on him. In addition, he actually does have quite a bit of experience with metallurgy and surface treatments, so I try to learn (but I do think he's jealous of me having a 3d printer). I've also got quite a bit of shop level background with metals, but not too much with power coating. After having Clemens' post nudge me and looking up the price for a new sheet - about $45, I'm not at all worried about it. Even if I cut the lifespan in half (which I doubt would happen), I'm willing to trade a few dollars down the road for the turn-around time to get my prints off a few minutes quicker when I print. I'm usually pretty impatient and I've seen enough people discuss actually pulling the coating off that I'd rather "shock" it a little if that helps break it loose and keeps me from pulling the coating off. It does make sense to me that it's probably not ideal, in terms of the maximum longevity for the steel plate (as Lynn was probably thinking) but I suspect the stress along the surface where the plastic is bonded to the sheet for printing due to the temp change is what helps break the print loose so easily.
Thanks for the input.
RE:
Difference in TE coefficients was an unstated assumption in my comments. TE for metals is much higher than for polymer, but I don't think it makes a significant difference for the thin layer of PEI on a satin sheet. The reason I'm not concerned is because of the flexibility & stretchiness (Young's modulus) of polymer.
Upon reflection, it could be a problem for a tightly bonded print on top of the PEI. That's been the problem with the smooth sheet and PETG prints. But in the case of the smooth sheet, it's a bonded film rather than powder-coated. I guess if your print bonds extremely tightly on the satin sheet, rapid-cooling could be a problem.
Another consideration would be the thermal expansion coefficients of the two materials and the bond between them. During temperature change, the coating must be able to expand with the metal plate and not break or weaken these bonds. The faster the temperature change, especially in the cooling direction, the larger the stress would be. There is a lot of advice out there to allow the plate to cool naturally before removing the print, I've always thought that was to prevent deformation of the plastic, but who knows maybe print surface failure is also a motivation.
Whatever you find to do with your hands, do with all your might!
RE: Cold Shock Damaging to Satin Powder Coated Sheet
Your over analyzing (your engineer friend is acting the fool) just do what you have been doing. it's fine.
Regards
Swiss_Cheese
The Filament Whisperer