Cutting styrene tube lengthways

I cut a couple of blocks of wood, identical size, then clamp them together and drill a hole the size of the tubing. I glue the tube into the blocks while on a table surface so the tube sits level and stable. Use just a spot of glue in each block so you can easily get the blocks loose'

Then I adjust my table saw to just cut into the lower half of the tube and run the block and tube unit along the fence.  Be VERY careful of your fingers!!!  Use the thinnest blade you have.

I would drill a 10mm hole in a scrap piece of wood,. Then insert a drywall screw (they have very sharp points) into the wood until it just pierces the hole. Draw the tubing through the hole being careful not to rotate it. This will score the tube in a straight line. tighten the screw a bit and repeat as nessessary to slit the tube.

Thanks

Carl

thanks tanker! great idea!

HI!, Grimmo! what I usually do, and I do it a lot on civilian vessels where the bulwarks and such have a rounded shape requiring this maneuver is--Take the tube and Put it in a slot cut into a piece of scrap wood longer than the tube.Fasten a stop at one end.You want the slot to hold the tube snugly with none sticking up above the piece of wood.Now,get out the good old panel scriber.Lay a rule over the tube on its centerline clamp it so it won,t move and use the scriber to cut through one side.Once you have that done take a retractable box knife(RED DEVIL or STANLEY)And gently do the same from the topmaking sure to keep your knife at the exact square set you need . when you are done ,you should have two pieces a little less that half a tube.The thickness of the panel scriber won,t matter ,believe me.I have been doing this in exactly this way for twenty years at least and have done my share of boo-boos ,but thankfully not that many.good luck! tankerbuilder   P.S. Make sure you put a fresh blade in the knife BEFORE you do the cut!!!

thanks mate! great ideas.

Sit the tube lengthwise into a slot (in a pice of wood maybe) so it cant roll around, lay a steel rule lengthwise along it so that is is "held" & run a craft knife over the tube against the straight edge of the rule - you may have to do this several time's to get a nice clean cut.

Sanding one half away would also be possible, but it might be difficult to get everything straight & even.

If you have one at hand & are VERY carefull, you could also run it over the face of a sharp plane, like a block plain - but if you slip you could loose the skin of the tips of your fingers!!