OK, I am fairly new to this, I have had some successes with what I am trying to do and several failures.
Generally I am embedding objects in rectangular blocks of resin.
I am using metal moulds (mainly cake tins) lining them with wax to ease out the resin once cured.
The issue I am having is that the five sides that were waxed seem to sand fine, but the exposed surface layer appears to be clogging up my sander (using a random orbit sander).
It's happened on 3 out of 4 sculptures now.
Wonder if anyone has any tips about preparing the surface, or using a different approach?
Thanks in advance.
HI POORUSHER. is there a way you can block the exposed areas with more tin after you have pored your resin such as with tin sheets that you can buy from the do it yourself stores and draw a profile around your exposed areas and cut them out to cover the exposed areas if possible.
I guess that would be possible, if I could cut it to size.
Edit: However I would like to know the best way I can sand the current sculptures as they are already cured.
HI LUKE. the other thing about clear embedding resin if you are using large moulds it is best to cast your resin by pouring it in stages because it will not cure in bulk as it is intended fore small plastic moulds for specimens.and it might be the tacky stuff that is blocking your sander so if you pore it in stages this should help the curing process you can also help the curing by putting the tacky cured resin if it is that in really hot water for an hour or so.
Yes for larger pieces I pour in layers, also as I am embedding objects I tend to do this anyway.
Also to finish the curing process and harden the resin I am baking it at a low temperature.
However one of the baked pieces still started clogging my sander.
HELLO AGAIN. sorry to be a pain but you can buy large or small different shaped plastic containers on the web including the shape you are using resin will destroy some plastic so you would need polyurethane plastic as im a bit sus about tin moulds but i could be wrong
No there is no problem with the moulds.
They are sturdy, reusable, and wax well, I can also sit them in a water bath if the resin gets very hot, and the issue is not with the waxed sides of the resin (i.e those in contact with the mould) it is the exposed top surface that seems to be causing problems.
I am wondering if there is a way to treat this surface before sanding.
I do have an angle grinder for a rougher treatment. But I would rather avoid using that if possible.
you could try wax polishing it first it might work i hope it works out fine for you.all the best. mick.
Try using wet/dry sand paper. lay it flat and pour a little water over it then use it to sand the bottoms of your pieces by rubbing them back and forth over the wet sand paper. You could start out with the coarsest grit then the finest. You would keep the paper very wet while working with it then simply use a cloth to dry the piece.
Just in case this is of use to anyone else in the future
I spoke to some chums of mine who make resin kitchen units. They recommend:
Post-cure: Bake the resin in a low temperature oven.
Pre-cure: Pour "wax in styrene" into the last poured layer.
Pre-cure: Cover the top layer with talcum powder.
The latter two stop air coming into contact with the surface layer.
Of course for the resin pieces I already have I think wet sanding will be the answer.
I'll let you know how I get on.
If the surface is remaining tacky try treating it with a 2 pac spray lacquer (for cars)