Cutting Delay & Smoke Grain from RCS

[beenthere2]

I am changing out some delays in AeroTech reloads and having a heck of a time cutting then out of the grain log from RDC, with parallel faces. Invertible the blade will slant and give say a 5.6mm on one side and a 6.1 on the other. I can use it as it is greater than 4MM but it can create some sealing issues and timing is based on the thinnest section much the same as drilling the center. Just wonder what other people have done/used to get an accurate parallel cut. If this has been asked before, I couldn't find it.

 

[prfesser]

Sort of like cutting a body tube. Wrap several layers of stiff paper around the grain, and using the edge as a guide, score it the whole way around with a stiff blade. The score line will help to keep the knife blade on track as you cut through the propellant.

 

[Steve Shannon]

Slide the grain into a piece of delay insulator tube and use that to mark around the circumference, then cut around it like Terry said. Then sand square.

 

[tfish]

a couple of ideas...
Do you or a buddy have a 3D printer? Seems possible to print up a sleeve and stop/spacers system to cut them to pre determined lengths.

To make it easier cut them all to long lengths then drill them to the desired length.

buy packs of them already cut to the right lengths..

Tony

 

[beenthere2]

Thanks guys. Yep I have already done the first two and 3d printed a tube with a spacer but there was too much wiggle room. I mean 1/32" is a second in time after the engine burns out, so the precision is exceeding my ability to stay straight as I cut. My best so far is like Steve said using the insulator tube and marking it and then cut it part of the way thru and then finish off the cut.

I even tried a cigar trimmer, but it lets the log tilt and gives a slanted cut. And then the right answer may be a combination of all of the above with the default being just buy them already cut. Like the commercial on TV says ..." It has gotten personal" ref squirrels in the attic. I was wanting something akin to a paper cutter type device with a fixed spacer.