meaning of "Bridge Layer"

[jferguson]

I'm having problems separating support structures from some very thin petg prints. I've messed around with the support parameters and think I'm on my way to a good solution but I need to know whether the "bridge layer" is within my model or is it the layer just below my model. On this particular design it makes a difference.

[brian442]

The "bridge" refers to plastic that is being printed in the air as it tries to bridge between 2 different foundations. So if you were printing a hollow cube, the first layer of the ceiling would probably involve a lot of bridging.

[Jaydawgx7]

I'm not sure how experienced you are with PETG, but most of your problem removing supports is in the material itself. PETG layers bond very well together, which makes printing with supports very difficult, even with good separation layers. I've had to cut out my supports. Between that and the stringiness of PETG if it's not dialed in perfectly, I've pretty much given up on it and went back to ABS and PLA. If you happen to have a dual extrusion printer, try printing the supports with a different material.

[jferguson]

I'm not sure how experienced you are with PETG, but most of your problem removing supports is in the material itself. PETG layers bond very well together, which makes printing with supports very difficult, even with good separation layers. I've had to cut out my supports. Between that and the stringiness of PETG if it's not dialed in perfectly, I've pretty much given up on it and went back to ABS and PLA. If you happen to have a dual extrusion printer, try printing the supports with a different material.

Useful advice. thanks. I conclude that a layer identified as a "bridge layer" in the colored display in Simplify must be part of the model. I also suppose that Simplyf3d looks at the layer below when it prints a new layer and if it isn't continuous makes new layer a bridge layer. makes sense.

I have a MakerGear M2 which is a lot bigger than the TinyBoy I started out with. Because of extruder construction I was afraid of printing PETG on that printer. I did print 6 spools of PLA with almost perfect results once I'd added a heated bed to it and another fan. Perfect results with PLA on the M2 and same with most parts with PETG. I think answer to my problem is to expect to CUT off supports and to redesign parts so there is enough meat in part to survive the cutting.

thanks again.

john