A while back, there was an MR article about cutting stone/rock castings made of plaster. Has anyone tried this? I have some that I’d like to cut the bottoms off of to “help” them stand where I want them but this seems a little risky to me. I can see the things just shattering.
Any experience or thoughts?
Thanks.
dlm
I can’t say how MR did it but my only experience cutting plaster or hydrocal castings have been first using a razor saw typically on the back side of what your looking to cut, in my case it was some W/S cut stone retaining walls and some tunnel portals that I felt were a tad too tall for my taste. The latter i cut down using a cut off wheel on a dremel tool. Not the same tool used for cutting rails etc. but this is a general purpose wheel if you will that they claim can cut anything so far they have been right about that part. A guy I know suggested pouring water on the piece that needed to be cut not so much for cooling it down but more for keeping the dust down. A good thought in hindsight.
If I have a casting of a stone wall with deep grooves and obvious “weak spots” between rows of stacked stones, then I will sometimes score with a knife blade and then snap the casting apart. Most of the time, though, I cut with a Dremel wheel, too. It makes a mess. I do it outside, if possible.
To smooth edges, try using sanding screen. This is a mesh material you can find with the drywall tools at your hardware store. The mesh works Hydrocal very well, and doesn’t clog with the dust. If I need to take a quarter-inch or so off the bottom of a castijng, I’ll use sanding screen. It’s more precise than the Dremel, and when you consider the cleanup time, it’s actually faster.
Mentioning Hydrocal castings, what I did when I put a bunch of retaining walls on one of my hills was to get a masonry blade that fits on a hacksaw frame. It looks a lot like a round mill file with loops on both ends to fit on the frame. (I got my blade at my local Ace and borrowed one of my Dad’s hacksaw frames.) It takes a little bit of practice to get it right. (I speak from experience.) It cuts through the Hydrocal fairly easily and it leaves a smooth edge behind. It can also be used to file edges if need be. As with a lot of the methods, it does leave a mess, but if one is careful the debris can be used again for other scenery methods.
I have cut plaster castings on a band saw, my table saw and also flattened the bottoms on a disc sander. Not once did the plaster break. I was cutting Woodland Scenics tunnel portals. I used a zero clearance insert on the saws when cutting them.
Don Z.
I used a Hack Saw, worked well for me. I all used a sanding block with 150 grit to get the bottom level.
Cuda Ken
Hi!
I have used a bandsaw quite successfully for cutting plaster and pretty much any other modeling media over the years. Make sure you go slowly, and have the exposed cutting surface of the blade just a tad higher than needed. Oh, wear eye protection, and WATCH YOUR FINGERS !!!
In addition to wetting it down, Be sure to wear a fine particle dust mask when filing, cutting, sanding the plastercasts!
Plaster dust is not very lung-friendly!