I am working on figuring out the best way to print a two-sided reliefed coin as well. I have see the following recommended solution on the interwebs:
print the coin standing on its edge
print the coin in two halves and glue them together
Both of these on face value seem sub-par to me:
translucency is greatly diminished when printing the coin vertically
layer lines are visibly and tactile, and go against the orientation of the coin, making it awkward and noticeable when handling and viewing
glue seams are visible and tactile when gluing two halves together
I have tried the following so far:
using support filament with 0 clearance to accommodate the relief on the underside of the coin when printing horizontally. this seems to work fairly well, but is problematic in separating the support material from fine details.
many colors are problematic and require manual changes (I have 7 different filaments) even if you have an AMS.
Here are two images from my first prototype where you can see the some of the issues with the support material on the one side:
My next prototype will include printing the coin in multiple parts, but printing the edge of the coin on one part, then inserting another part into the center of the coin, so that there is no assembly seam. I am worried about a visible gap line though. I also will plan for a hollow area to insert a metal washer to give it some weight.
PS: @BillByrd not meaning to highjack your thread, but it looks like weâre trying to solve a similar if not the same issue. Thought it might help if I share my journey here as well.
What I meant was that I donât have AMS. I have different color filaments. But hey-- check this out: Printed on edge. Both sides beautiful. A testament to the PEI textured plate in combination with BBL liquid glue! Just keeps getting better!
@Mike_Bronner - I havenât even tried it to know, but would dissolvable support interface material let you use support at zero clearance and not mess up your print when removing/dissolving it?
Thatâs a good idea, I havenât tried that either. Will look into it. I will first try again using support material in the hollow areas of the multi-part print, as that will not have any fine details to separate.
Yes. Different colors. They will be a personalized gift.
The bridging on your example is what I was hoping to get away from. Printing on edge seems to be the way to go (so far).
I have a spool from Bambu of it. Havenât used it yet.
It doesnât make PLA supports obsolete though. My understanding is itâs just used as the interface between the supports and model. That way you donât have all the filament swaps each layer and itâs kind of expensive to actually use as support anyway.
Others have said using PETG as support interface works really well too since PLA apparently doesnât stick to it. And you can also apparently use PLA as support interface to PETG.
But I donât have experience yet with either so canât really comment any more than that.
With multiple colors, printing on edge may still be a problem. One obvious one is youâll need to do a lot of color swaps and without an AMS thatâs going to get tedious. It also will up the chances for knocking them over and other issues with delicate prints.
Printing them flat will really reduce the number of swaps youâll have to do.
When using a different material as a support, it is far smarter to use it as a support interface rather than supports.
The difference is:
Supports
Works from the build plate up to the model, in some cases, from the model to taller parts of the model.
Support interface
Only appears immediately below the point the support would normally touch the model.
Benefits, using a different material designed or coincidentally not capable of fusing to the model means it is easier and usually cleaner to remove.
Problems, using a different material would require a filament swap on each and every layer, time and material wasting.
Best case, support interface. This provides all the benefits of the different materials, but, the only time the support material needs to be swapped out is the layer immediately below the actual model material.
The support interface material is used for only those contact layers and significantly reduced waste.
Whilst using PETG is cheaper than specifically designed materials, using it as the interface layer rather than the entire supports is also far faster due to the far fewer material swaps.
When my non printer friends marvel at some of my output, I always remind them-- Itâs not me! Itâs the technology. I just draw things and send them to the BBLs. Glad I got to be a small part of it before checking out. When I was born in 1945, they would have thrown a net over you for even suggesting such things would ever exist. I guess my favorite is DNA.
