Liquid Sprue?

Just chop up or grind some sprue into an old paint jar & add some liquid or tube adhesive, stick the lid on & leave it overnight. By the time you come back it should resemble liquid plastic, if it doesn't try adding some more glue, giving it a stir & leaving for a while longer.

Use liquid glue; Testor's Liquid Glue is the ideal medium. I wouldn't use tube glue. That stuff is just too unpredictable and slow-curing.

Hello!

For extra cheapness, you could also use lacquer thinner instead of glue. At least that's how I do it. And I love the liquid sprue - it's not only cheap, almost free, but also has great adhesion to styrene and cures the problem I had with other putties - the cavity I tried to  fill with putty "came out" again after a week or two. With liquid sprue that doesn't happen. It's downside, though, is a somewhat long drying time - about 24 - 48 hours, at least for my sprue plastic/solvent type combination. Hope it helps, have a nice day

Paweł

Straight MEK is about the best medium to mix sprue up in.. But it's H-O-T, HOT stuff... It's the base-chemical for liquid cements, like Testor's Pink label..

I second the use of MEK. Works great!

Chop up some sprue (you dont have to, just makes it easier and faster) and place it in a clean bottle with the MEK. If it is to thick add more MEK, to thin add more sprue.

I'm not sure if the plastic bottles would work. I use glass bottles.

If you want to save the mix make sure the bottle has a good sealing lid or the MEK will evaporate.

FYI- In another thread on this site is a discussion on MEK possibly been discontinued  by some big box retailers.

Sounds easy enough, thanks for the help.

Out of curiosity..........is the sprue/ MEK mix easily applied in layers ( after each layer dries ) ?

Has anyone tried using the mix to cast small , low relief ( 3 sides ) objects rather than use resin mix?

Have you guys had any luck with this? 

 When I get the sprues cut up into little slivers, I can't get it into a jar or cup to dissolve it. Due to static, it just sticks to my hands, the knife and everything else but the bottom of the jar.

Just thinking as I was typing, maybe I should try stretching some sprue and then stuffing that into a jar.

I do a similar trick with putty and acetone, mixing it in a well on a ceramic palette, and applying it with an old dental cement spatula.

dmk

Have you guys had any luck with this? 

 When I get the sprues cut up into little slivers, I can't get it into a jar or cup to dissolve it. Due to static, it just sticks to my hands, the knife and everything else but the bottom of the jar.

Just thinking as I was typing, maybe I should try stretching some sprue and then stuffing that into a jar.

How small a piece of sprue are you cutting?  I would use a wire cutter or sprue cutter to cut the sprue into small bits, eg, 1/8 " or so, and soak those in the fluid, stirring until they dissolve.

the Baron

How small a piece of sprue are you cutting?  I would use a wire cutter or sprue cutter to cut the sprue into small bits, eg, 1/8 " or so, and soak those in the fluid, stirring until they dissolve.

I used a pair of wire cutters (didnt wanna wear out my sprue cutters) to cut the sprue into pencil eraser sized pieces. I cannot say how long it takes to dissolve as I've always done it at night right before I go to bed. It has always dissolved by the next day.

I would guess that it takes several hours depending on the sprue size. I know it doesnt start dissolving immediately. Its definitely not something you are gonna want to sit there and watch it happen.

I'll try a set of wire cutters. Didn't think of that.

I was slicing off very small slivers for immediate use.

 I will say, the little bit I did get to use was very easy to work with since it's the same hardness and color as teh plastic. It sands nicely, cuts nicely, perfect for anything that needs to be scribed.

dmk

 I will say, the little bit I did get to use was very easy to work with since it's the same hardness and color as teh plastic. It sands nicely, cuts nicely, perfect for anything that needs to be scribed.

I've not used the stuff for any sort of regular filling yet, but I have used it for a few edge & corner repairs where filler simply wouldn't have cut the mustard - although it's not the easiest to work with & does seem to take a couple of days to set properly, it worked VERY well, being as strong as the surrounding plastic, easy to sand to a good finish & having no desire whatsoever to pop out. 

dmk

I'll try a set of wire cutters. Didn't think of that.

I was slicing off very small slivers for immediate use.

 

 I will say, the little bit I did get to use was very easy to work with since it's the same hardness and color as teh plastic. It sands nicely, cuts nicely, perfect for anything that needs to be scribed.

I dont believe this method will work for "immediate", "spur of the moment" use. It needs to be prepared ahead of time.