Does anyone here do 3d printing?
I want to make some small fixtures to hold a part in place on a PCB as it passes through our reflow oven. I was planning to machine it from aluminum and steel, but it would be cool to 3D print it if some material would stand the temperature, maybe 250c peak.
UV resin printing, maybe. Nice and quick for cheap.
Cheers
Phil Hobbs
Yes. In fact there are UV LED+LCD printers for $125 or so, with 17-um voxels. Elegoo is one brand.
Cheers
Phil Hobbs
Another option is making a simple wax model of the fixture and then make a mold (lost wax) using Smooth-on.com's high temperature epoxy resins along with their flexible molding materials.
I use their products for quick reproduction jobs of various parts we need...
John :-#)#
There is also 3D printed lost wax process type stuff which provided the shape is half way reasonable allow you to 3D print in a material that can be melted or burnt out of the moulds and then cast in aluminium.
There are some print heads that claim to do 300C so if you can find a plastic that needs 260+ to soften you might stand a chance. Worth talking to your local makerspace guys - they like a challenge.
No but there are some UV cure 3D resin printer systems that produce plastics that are rigid and crosslinked (so don't soften so much with heat) that might survive in an oven for long enough to be useful in reflow oven soldering. They might not last for many passes though.
250C might be a bit much to ask, as I think most "heat-resistant" 3d-printable thermoplastics (PEEK / PEKK / PPSU / others) are only good to around 200C (+/- a bit).
Admittedly though, I don't have one of the printers that runs a chamber up to 100C (or can get the nozzle up north of about 250C); so haven't really looked into the materials much past "oh, I can't use these".
One solution is to use the 3D printed part to make a mould for casting the final part in another material. JB Weld epoxy claims it "can withstand temperatures up to 550F when fully cured". That's
305C. I've 3D printed a part in ABS, then pressed it into a cut-down disposable plastic cup filled with silicone sealant. Once the silicone is fully set, the cup can be flexed to release the plastic part, leaving a perfect mould into which the epoxy can be poured. I found it worked very well for a higher-temperature application, but JB Weld is quite brittle so it wouldn't suit all applications.I've also done aluminium casting using the Lost Wax process, but with 3D-printed ABS instead of wax. The basic idea is to put the
3D printed object (painted with a paint containing bits of ceramic) in a bucket full of fine, dry, sand, and pour in moulten aluminium which melts out the ABS while simultaneously filling the resulting cavity in the sand. That worked well sometimes, but it's not easy and there are a lot of details to fiddle with, not least building the furnace!Have something to add? Share your thoughts — no account required.
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