We have a problem with printing text relief on our prints.
As you see above letters are kinda “shifted” or something. They are “dragged” to distancce of 0,1mm. Always. We tryied to print exactly on the center of printing area but it doesnt seems to make any difference : / .
This print was oriented in vertical to the build platform. I think we have tryied to make print horizontal but the letter also were kinda shifted.
Dont have any clue how to print letters well.
Ì think it’d be interesting to have the STL file (not the .form) in order to get a better idea of the sizes of the features and how the 3D model is made.
It seems strange that only the letters print badly and not the other features, I would suspect an issue with the mesh of the 3D file.
Unfortunately stl has sth about 2gb+ and for our internet provider it will be nightmare tu put that file anywhere.
Do you have a STP file or any other lightweitght format ?
2Gb for a part of this size, even with details, seems a bit overkill.
If I understand correctly, you are referring to the letters that have sudden horizontal overhangs without support. I do not think this is a mesh or slicing error. In this case, the initial start of the letters are ‘flaps’ that may curl and produce slanted bottoms. The top features of the letters should be in the correct position (you should measure to verify.) It looks like you are printing this at 0.025mm layer height. You may have better luck at 0.05 because the layers are thicker and more rigid (inertia increases as the cube of the thickness.)
This deflection may also be asymmetric with peel direction. Try a few different rotations about the Z axis - perhaps there is an optimal position for the most important face if there is one.
Good luck and let us know what you find. Feel free to post more pictures and highlight the defects and label with dimensions and directions so we have all the information.
If you don’t have anything on the back side, then it would help to make the print more stable by putting some supports back there. Usually most issues are due to lack of support or lack of stability.
Also, as far as how the model is made, make sure that any separate meshes are slightly intersecting if you want them built together, if you have coplanar surfaces it will create artifacts.
Do you get the same effect when printing a colored resin like grey?
The posted pictures looks to me like the shift is dead vertical- which if consistent means its likely not a peel function…
It could be that the thin rim of the letter as they are printed are sagging- as Adrian pointed out.
but it is also possible that the laser light can penetrate the clear resin deeper than the layer thickness and partially cure the wet resin above the submerged previous layer. if you get better results with a colored resin this might be verified.
That is- its not SHIFTING the letters’ positions- their top faces look correctly centered on the arc. What it is doing is Adding a draft to the upper surface of each prominence of each letter. The letters are drafted only on the platform side which gives the appearance of them leaning,
Also- lay the surface back around 45 degrees- if this is a two sided coin, then split it down the center so you can have supports on the back of each half, and just glue the two halves together.
Thanks everyone for reply! We will try to print with 0.5mm resolution. Meaby this will help. Orienting the print differently doesn’t seems to help. Laying down prints with 45 degrees is also no no. We cannot glue parts together beceause of purpose of those prints. They go through vulcanization process so any kind of connections cause to breake prints. I hope that 0.5mm will make difference.
Gluing the parts together with Form 2 resin is possible. A 205 nm flashlight will cure the resin. The flashlight won’t penetrate all the way through the coin so it would need to be “glued” in layers. Requires some good finishing work though.
try pigmented resin- if the laser is curing resin THRU the initial letter layers this might solve it.
Do you mean that I should add pigment to the original mixture or try resin that is already pigmented ?
Grey, black and white are pigmented Clear resins, this is what @Sculptingman meant I think. It’s a good idea however White and especially Black will probably not give you a good enough resolution for the small features you are printing, grey on the the hand is very good with fine details (better than Clear) so it’s worth a try,
Unfortunately there is no way to use other resins than HighTemp. We need it to be resistance to 200 degrees : )
you could experiment with the formlabs pigments- in open mode- but i am not sure that would not affect high temp resistance- the pigments might pyrolize at those temps.
It sounds to me like you are using the print as a pattern for pressing a vulcanized centrifuge mold… is that right?
Is that the case?
If so Consider that its also possible to print in Castable- which has a pigment- and then use a traditional investment mold process to burn that out and cast bronze patterns that can take 1800C you can compensate for shrinkage in the print… and I would advice printing both sides as thin shelled halves glued together to allow the pattern to swell internally during burnout.
This is my preferred process for producing high temperature patterns for vulcanized molding. The bronze patterns are rigid and can be used as masters to press hundreds of molds over their lifetime. Being ductile, they are easy to both polish out any visible print raster, as well as sharpen details with a fine chisel punch or engraving point.
Another way to go to get maximal detail, would be to print the pattern as a split master- separate obverse/reverse
sides- each relieved proud of an integral separation plane with simple keys- gates and vents.
Take a silicone mold from each half master- and the two molds would fit together to from a single mold for casting
multiple copies in metal filled resins that can take suffcient heat to be use in producing a vulcanized mold.
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