Stiffening a PVC Pipe

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#1 walkerofdarknes on 1 year ago

So I'm making a basic scythe for this year's backup cosplay. Since the handle of it is round, I opted for 3/4" PVC pipe. The problem is the size of it: at the projected 6' length, I've got a noticable wobble in the pipe. I picked up a dowel rod that's SUPPOSED to be the same diameter, but is just a hair or three smaller than the pipe. And the 1" dowel was not going to fit unless I ground it down, which just isn't fun to do on a length like that.

So there's my dilemma. I could use plaster/concrete to fill the PVC but I want to save on the weight. Should I stiffen it with something like spray foam (although I'm uncertain if it'll reach down far enough). I do intend to fiberglass the pipe for a faux-metal appearance, however I doubt that'll give it the rigidity I'm looking for. (And yes, I do acknowledge the joke about a guy asking how to make something hard.) Any ideas?

#2 Midnight Dawn on 1 year ago

Try an acrylic pipe at Tap plastics.


#3 nathancarter on 1 year ago

I'd just replace it with a shovel handle, or a wooden curtain-rod dowel.
If you gesso it and sand it, you can get a slick surface that can be painted with the same metal-effect that you intended to do on the PVC.


#4 Dictamnus Albus on 1 year ago

honestly, you might be making a bigger deal of it than it really is,

stick the slightly off dowel in the pipe,
fit can be improved with a few wraps of tape or gob of hot glue,

if the idea was to just kill the wobble/sag, just having the wood in the pipe will fix that

though my preferance would be to lose the pipe and just use the wood
(assuming the rest of the project hasnt already been built to the pipe specs,
but thats a similar fix, of making the wood fit)

also, for future referance, spray foam wouldnt do squat in this case,
the common gap filler is low density and either, remains semi-flexible, or dries up gets brittle
and starts chaffing and crumbles into a nasty off-orange dust

the construction grade abc? foam is denser but your probably looking at high costs
and (for the purpose) unreasonable quantity of material

#5 walkerofdarknes on 1 year ago

Well, I suppose I should elaborate some on the weapon. I put a "simple scythe" before, but it's not quite that simple. It's essentially a boar spear (that has two cross arms about 9" from the top) and the scythe blade is mounted on one of the cross arms. I chose PVC pipe for it because I'm going to make the blade from EVA foam and stick a heat shaped pipe in for a skeleton, then use a straight coupler to allow me to pop on/pop off for transport. Plus, the PVC has a cross coupler, which means I don't have to deal with hassle of drilling through to put in the's a link [URL=""][/URL]

#6 nathancarter on 1 year ago

Use a dowel, and inset a 2"-long threaded rod into one end of the dowel, so there's about an inch sticking out. Put a nut (better yet, a wingnut or insert nut) inside the PVC cross-coupler and fill it with JB weld or epoxy or something, so the cross coupler can screw onto the top of the dowel.

I did something kinda similar for my wasteland shaman staff; but because the coupler is horizontal instead of vertical, I didn't inset the nut into the coupler. I just drilled a hole so the threaded rod pokes all the way through the coupler, and I can thread the wingnut on top of the coupler. You can just barely see the wingnut underneath the cauldron here - I don't have any closeup photos handy.

The 1/4x20 x 2" threaded rod is glued into a hole I drilled in the top of the dowel, and it's plenty sturdy.