Tips for a newbie?


#1

I’m relatively new to the Form2 and am not printing for professional reasons. I’m mostly printing 28mm miniatures and scatter terrain pieces. I print a lot of HeroForge models. I have a few challenges that I’d love to hear your thoughts on them.

  1. I’ve been trying to just use the automated PreForm preparation, but the web of supports are really hard to removed without damaging the model. Should I try removing prior to curing? Should I start trying to use fewer manual supports?

  2. Some of the pieces end up being pretty fragile. I’ve used standard gray and clear resins. Any suggestions on resins that might provide a little more strength to smaller areas like tiny weapons being held by figures?

  3. I’d love to consider casting some of these. Any good primers out there on how to get started casting miniature figures from castable resins?

Thanks all!


#2

1- you can try making the support attachments smaller and fewer- like with anything, practice will be the most instructive.
Also- the most important thing you can do for better prints and control of supports is often to print a figure in more than one piece. Sometimes something as simple as printing the upper and lower halves separate can make for a much better print with a lot less support needed.

2- Some folks swear by the dental resin for high detail.
Tough is pretty good- but won’t print at highest resolution.

3- the simplest way to make High accuracy molds for small detailed items is to use paper dixie cups.
-A- Buy a package of dixie cups. The kind with the simple straight tapered walls.

B- Mount your master to a board and add to it any vents you might think will be needed to enable air to escape from things like outstretched arms… do this my simply using needle nose pliers to bend wire into a vent. Most importantly, try to imagine that the mold will ultimately be cut open in 2 or three parts… and you want these wire vents pretty much follow the path you imagine this cut line to run. Drilling tiny holes in the board roughly in plane with the imagined cut line you can shove the bottom of these vent lie into the holes to hold them tightly in place, running several mm off to one side of the master and only coming into contact at the specific point you want air to be able to get out of.
The Line you will cut the mold open on is called a “separation plane” and it will be a sometomes complex single plane that will separate the rubber running thru any closed loop in the figure- like, say a figure has their hand on their hip- this creates a hole thru the crook of the arm- entirely surrounded by resin. the Rubber mold will fill that hole and you will have to cut the rubber in half along the narrowest part of that hole so you can pull the cast part out…
Think of the vents you will place on the separation plane as ALSO being GUIDES for cutting the mold open when its cured.

C- So once you have the model mounted, Take a dixie cup… and cut a hole in the bottom. Place the dixie cup, upside down, over your master and use some plastilene or hot glue to stick the rolled rim of the paper cup to the board. Look thru the hole to ensure the cup fits neatly around the master without touching the model. It is important to pick a Size of cup such, that the bottom of the cup- now sticking up- is half to 1 inch HIGHER than the top of the model and vents you are molding.

D- now mix silicone rubber and vacuum it to get rid of air bubbles… if you don’t have a vacuum pump- then just try and pour the silicone into the hole in the dixie cup in a stream no thicker than 1-2 mm- this should break 99% or any air bubbles in the mix.

E- as the dixie cup fills with silicone- make sure you STOP filling the cup about a quarter inch BEFORE the silicone gets to the top of the cup. you want an air gap between the bottom surface of the cup that you cut that hole thru and the silicone.

F- when the silicone has cured, tear the dixie cup off and pry the mold and master off the board. Take an xacto knife and cut the mold in half along the separation plane that will best work- if you placed your vents correctly, you can have the tip of the knife follow the vent wire as a way of guiding your cut to be more accurate.
Cut the mold into at least 2 fully separate halves.

Once you have the mold cut- and the master removed, you can also cut any additional vents you feel might be needed.

G- Now- re assemble the separate mold parts and drop the assembly into another fresh dixie cup. The dixie cup acts as a mold casing- that holds the mold parts in accurate alignment for casting.
Because the mold has shrunk a tiny bit… the mold will slide DOWN into the dixie cup a little further until the seam lines on the mold close completely. In this way you are taking advantage of the constant smooth taper of the dixie cup to eliminate any flashing lines- which can be problematic in such small castings.
the reason you want to make sure you stop filling the cup with an air gap between the upside down bottom of the cup and the silicone is so that when you put the cured mold in a fresh cup it will be ABLE to slide a little further down inside the cup to close the separation line perfectly tight.

You might also need to cut a small hole in the bottom of the cup you use as a mold casing- and perhaps talcum powder the inside of the cup a little, just to make it easier to demold.

You can now filled the silicone mold with resin for cast parts.

Urethanes are usually the best for casting small parts- they are generally less brittle
.