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Tube rolling help


insutama

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Im looking for any tips on rolling rocket tubes i just bought 50lb kraft paper 12" wide. It seems as after the tubes dry when i put rammer down it pushes the first layers of paper out making my tube inside diameter too big. I try and roll a half roll on to my dowell before i add glue im trying to avoide the tube sticking to the dowel but at same time want that first roll tight so it doesnt push out. I really wish i could just buy a tube roller but cant find anywere selling one.
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Don't use a wooden dowel, or fill, polish, and wax it heavily before use! Usually dowels are not round-enough nor smooth-surfaced enough to work well as rolling formers, and since they're porous if not surface-treated, they're a poor choice of former material for paste-n-paper work.

 

A piece of polished SS or aluminum rod is more suitable. Wrap only, exactly one unpasted turn around the former. Paste should start immediately where the first wrap begins to be covered with the second turn.

 

When the tube is fully-wound, give the former about a half-turn counter to the paper's winding direction, in order to help alleviate any adhesion between paper and former.

 

If you've wound it correctly, with LITTLE-enough paste, you should then be able to extract the former while still twisting it counter to the winding direction.

 

If you got the paper too wet, it will warp badly without the rod inside, and will need to be dried on the former. In that case, turn the former about a half turn every day while the tubes dry in a warm (not hot) drying environment.

 

LLoyd

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Awsome thanks for the advice i guess now i gotta go find a new former i have a steel round bar but its not polished wonder if that would work
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I am having one made for me by a friend, I'll shoot you some pix when its done.

 

One of the things I noticed when hand rolling tubes, make sure to PUSH the tube off the bar, never pull. I have a yolk in my vice made from brass (no scratching) that helps pull the tube off the rod and a brass ring to fit over the rod in case I need a little more help. Finally, if I did glue the rod in, I also have a hole drilled in the rod behind the ring to use a come-along to pull the tube off the rod.

 

Yes, I can pull paper off the tube doing this but most is still usable. I did find that if I go over the one wrap of dry paper by 3/8", the glue will work back to almost the edge of the paper starting point.

 

BTW- my last tubes were wound with pre-glued paper, applied with a 9", 1/4" nap roller cover and 50/50 white glue and water and the sheets were left to dry. The dry paper was then lightly wiped with a sponge to activate the glue and wound. ROCK hard tubes and no air pockets. Very nice stuff!

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Fisrts post here.

 

I made successfully 12mm ID tubes both from wood dowel or uncalibrated steel pipe.

 

The only trick I used is to apply a generous amount of paraffin to the former or wax. Clean any residue after demolding the tube, and reaply a lot of paraffin.

 

I made them with a homemade machine, that I scraped because it was not precise enough, and very slow if I wanted a good tube, and are designing a new one. I will post the drawings when done.

 

O, I used sodium silicate as glue. Cheap, rock hard when dried, and fireproof.

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Fisrts post here.

 

I made successfully 12mm ID tubes both from wood dowel or uncalibrated steel pipe.

 

The only trick I used is to apply a generous amount of paraffin to the former or wax. Clean any residue after demolding the tube, and reaply a lot of paraffin.

 

I made them with a homemade machine, that I scraped because it was not precise enough, and very slow if I wanted a good tube, and are designing a new one. I will post the drawings when done.

 

O, I used sodium silicate as glue. Cheap, rock hard when dried, and fireproof.

 

Also, using only sodium silicate makes brittle tubes. For a 1/2" tube, I doubt it matters but when you get to a 3# tube (25 mm) you will have issues with cracks when pressing or ramming.

 

I applaud you for finding a method to remove them from the rod, over here in the states, we call ALL paraffin wax.... Mineral Oil is paraffin in many other countries.

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I have a few months forward to find it, and find a better method. Sodium silicate was also the glue that wrinked less the paper.

 

For demoulding, I'm using solid paraffin, the kind i'ts used when welding copper.

 

I have only done a couple dozen rockets, all 12mm ID, for the summer solstice (Firecrackers and rockets everywhere here in Spain), so my experience is very limited. And all thanks to forums like this or Ned Gorky´s videos.

 

I recognise I'm more a maker than a phyro, what I like is making tools and machines to make the "perfect" rocket, and experiment optimising it. So making the "perfect" paper tube, and the tooling to make them is one of the jobs I have until new years eve arrive and I fire a new salvo of rockets.

 

I have to try pregluing the paper like you did. Seems interesting for avoiding the wrinkles in the moist paper.

 

Thanks a lot.

Edited by Baldor
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what weight of paper is mainy used in pyro i got 30lb 40lb and 50lb that should be all i would need for building canitster shells and rocket tubes right ?

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what weight of paper is mainy used in pyro i got 30lb 40lb and 50lb that should be all i would need for building canitster shells and rocket tubes right ?

 

I use 70lb paper for making my canisters but 50lb will work too, you just need wore of it to make the same thickness. I use 40lb paper to roll my tubes, only because it's what I have the most of and it's available via Uline for $32 a roll. I really wish Uline had 70lb paper too, I would love to have a roll 24" wide for my 3" shells.

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Lol i ordered from uline alsoi got 30 40 and 50 what would the 30lb stuff be good for?
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30lb is perfect for over-wrapping rinfasciature shells or pasting-in around time fuses on spherical shells. Some people (me, one) will ONLY use 30lb on pasted shells, no matter how many layers it takes (and ball or cylinder). I don't like the way heavier papers 'lay'.

 

Lloyd

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Intresting so you use the 30lb for pasting ur shells or for going on after the shell is pasted to hold lift?
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I love a subject I can actually comment on from experience! I make my initial canister headings from #70 and the second wrap from #40 paper. The lighter paper takes more turns but pleats better in both pasted and rinfasciature methods. I would use your #50 heavier paper in the same fashion. I expect to be corrected momentarily so wait a bit before following my advice....

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No wonder my paper tubes are so heavy. I have been using 45gsm (about 30lb) craft paper, there must be more glue than paper in my tubes. :-)

 

Problem is, I can not find heavier craft paper in rolls of manageable size (I'm using 150mm and 300mm wide rolls). Some suggestion about what to look for? The only 70lb paper I can find is plotter paper, expensive and 1m wide, or some low quality packing paper too wide also.

 

Apart from more work winding the tubes, Is there any deleterious effect using so light paper that I must consider?

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I love a subject I can actually comment on from experience! I make my initial canister headings from #70 and the second wrap from #40 paper. The lighter paper takes more turns but pleats better in both pasted and rinfasciature methods. I would use your #50 heavier paper in the same fashion. I expect to be corrected momentarily so wait a bit before following my advice....

 

Same thing here, 70 lb for the canister itself, chipboard liner, 40 lb for the paste wrap. Like Lloyd mentions, the 40 lb seems to lay down better than 70 lb. I use 30 lb recycled kraft for the over wrap, I have never had it come apart on me but I don't build large shells either so virgin may be needed when they get heavier?

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so rolled some 1/2" ID tubes turned out great except the first wrap came up a bit when i put it on the rocket tooling so im thinking my woodglue/water mixture is too diluted ill try again and just do a single bead of straight wood glue for the first wrap see if that helps.

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Would you say that kraft paper bags the big ones (mine are from Canadian tire) are a heavier kraft paper than say 50lb kraft ?

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They're generally about 60lb. Some are as heavy as 75lb. Yard waste bags tend to be heavier than normal paper. Unfortunately they also have next to zero wet strength.

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So would i be best using 50lb kraft paper or a kraft paper bag for my canister shells first wrap?
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so rolled some 1/2" ID tubes turned out great except the first wrap came up a bit when i put it on the rocket tooling so im thinking my woodglue/water mixture is too diluted ill try again and just do a single bead of straight wood glue for the first wrap see if that helps.

 

What I do when that happens is just lift it up some using something long and thin like a bamboo skewey and smear some straight wood glue all up and down and push back in place with the skewer then back over what you rolled it with.

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If it's less than one turn of paper, I just remove it and forget. There will be little difference.

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Im talking about the first wrap comes unrolled on the inside of tube after its dry and i put tube on toiling
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Yes, it's what I'm saying, sorry for my english.

 

I did a few dozens of 12mm tubes, with various methods. With some, half the first internal layer broke loose for lack of glue when inserting the rammer (I always test the tubes with the rammer before mounting them in the spindle). I just teared the paper that the rammer get loose, and proceeded as usual. I was using very thin paper, so maybe with thicker paper this could be a problem.

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