Material for large print bed

Ciao,

I am building a very large printer 1300mm x 800mm and wanted to investigate different materials for the print bed without heating.
Currently I am opting out for glass and looking at aluminum 3mm thick.

The printer will print different materials as I am building a dedicated 4 materials extruder.
Any suggestions on different materials for the bed?

Requirements are:
No heated bed
Very large surface 1300mm x 800mm
As light as possible

Alessandro

Look at PIR foam. It is sold inexpensively, almost everywhere, as fire retardant building insulation in large sheets that are easily cut to required size with a razor knife. The foam usually has paper/foil on one or both sides that is easily peeled off to prepare it for printing. The foam does not break down chemically at extruder nozzle temperatures (see video here: https://www.youtube.com/watch?v=RXan0uONA04).

ABS sticks. I haven't tried other materials, but the bond is mechanical, so it probably works with other materials, too. No heating and no bed leveling are required- just bury the extruder nozzle about 1mm or so into the foam and print on a raft.

Video here:

https://vimeo.com/66558877

https://vimeo.com/66108108

Ciao,

super cool !!!
Looks like I found what I was looking for

Thanks a lot !
Alessandro

Ciao,

funny, but I am having problems to find an online store here in Europe that sells these type of panels directly to consumers !!!
Hopefully on Monday some store will respond to my emails.

BTW any suggestions on the panel? Should be only of PIR material not covered with other foils ?

Thanks
Alessandro

Edited 1 time(s). Last edit at 06/20/2015 05:41PM by biskero.

PIR foam sheet is usually sold for building insulation with paper/foil on one or both sides. It is easy to peel off the paper/foil. Be sure to get PIR (polyisocyanurate) foam, not polystyrene foam (usually pink or blue) which decomposes and produces toxic vapors at extruder temperatures.

In the US you can buy PIR sheets at Menards, Home Depot, and Lowes home improvement stores for $15 for a 4' (1.22m) x 8' (2.44m) x 1" (25mm) sheet.

It sorta depends on what properties your looking for, but if it's not a heated bed, that opens up some possibility.

Polished stone and/or ceramic tile would be an easy way to go but it might not be a very light option.
The high hardness would allow you to be a bit more blaise about detaching pieces from the tile/stone and those can be made to have high degrees of flatness and rigidity.

Allot of the lighter options, depending on how fast you want to print, can bend and flex, especially with hot molten plastic being sprayed on them.

You might look at a high temperature epoxy, such that you can get at an automotive store for repairing gas tanks and engine blocks.

It's a lighter option. It would take some work, and you might need to mix in some not-so-fun stuff like fiberglass, but it could be done to be hard, rigid, and relatively durable.

Finally, as a thought, Have you considered a teflon cutting board cut to the correct dimensions?

Teflon is basically the same thing that's in the liner of many J-heads, so a good cutting board made out of teflon would probably hold up ok. You might need to plane it so that it has the desired smoothness though. Alternatively, you might try a coating of aluminum foil.
With that in mind, perhaps just leave it at "Have you tried any cutting boards?". Most are made to be heat resistant, at least partially, and all are hard and rigid so that seems like it'd be ok.
You might need to use a coating, like aluminum foil or a bunch of tape, to aide in the removal of the piece from the print bed after printing, but something removable is usually manageable.

I think you're mistaken about cutting boards. A 1/4" thick x 12" x 24" piece of PTFE (Teflon) costs $~200 (http://www.amazon.com/dp/B000ILHVXU/ref=biss_dp_t_asn), so the ~10 sqft the OP is looking for would cost ~$1000, assuming you could find a single piece that large. I suspect that's a little more than anyone wants to spend for a print bed to which parts won't stick. A quick perusal of these forums will demonstrate the myriad, much less expensive ways people have found to make beds to which parts won't stick. Generally speaking, parts need to stick to the bed in a 3D printer because when they don't, the print fails.

You're probably thinking of PE or HDPE. It's cheap stuff, often used to make cutting boards, and it's sort of white like teflon. It has a very low melting temperature (about 130C) that would make it unsuitable for use as a print bed material, even if parts could be made to stick to it.

Ciao,

to me the PIR looks a great solution since is light, cheap and does not require the heat bed.

I am printing mainly with carbon fiber and nylon plus HIPS support material so hopefully they will stick !

Hope to have some answers from resellers on Monday.

Thanks
Alessandro

Quote
the_digital_dentist
I think you're mistaken about cutting boards. A 1/4" thick x 12" x 24" piece of PTFE (Teflon) costs $~200 (http://www.amazon.com/dp/B000ILHVXU/ref=biss_dp_t_asn), so the ~10 sqft the OP is looking for would cost ~$1000, assuming you could find a single piece that large. I suspect that's a little more than anyone wants to spend for a print bed to which parts won't stick. A quick perusal of these forums will demonstrate the myriad, much less expensive ways people have found to make beds to which parts won't stick. Generally speaking, parts need to stick to the bed in a 3D printer because when they don't, the print fails.

You're probably thinking of PE or HDPE. It's cheap stuff, often used to make cutting boards, and it's sort of white like teflon. It has a very low melting temperature (about 130C) that would make it unsuitable for use as a print bed material, even if parts could be made to stick to it.

Ahh... nah I was thinking PTFE, but it's been several years since I looked at the cost of teflon, and it's apparently done nothing but climb. I used it in an aquaponic build i setup for a friend at that time, but it was maybe half the cost. A bulk discount might have also come into it.

If PIR works, it's not really an issue, but I'd be worried about the rigidity of the product. Large prints can be heavy, even if it's plastic, and that could cause deformation of the build platform (especially since it's also plastic). I'd test it out a bit to see if it's okay.