Tube Roller - 4oz - 1 # and 3 # or more

[Col]

The glue is important but how its put on the paper will have a big effect on the finished tube, If you pour the glue onto the paper you`ll be putting more water in some areas than others. Paper changes with moisture content so ideally,you want an even film of glue over the entire sheet without any excess, applied as fast as possible.

Here`s some useful info on the different kinds of glue machines http://www.schaeferco.com/about_rollcoaters.html

Edited October 2, 2014 by Col

[stix]

Yes indeed Col, it's ALL about the method.

[Col]

I reckon we should be able to come up with something smallish, cheapish with an integrated inline glue section to roll tubes upto say 12" long. The only tradeoff is the roll of paper would need to be precut across the width into 12" strips and temporarily reconnected end to end (using masking tape) so it can be driven through the glue section in one continuous strip rather than feeding seperate sheets which gets messy. The sheets can be overlapped during the taping process to create the correct dry margin width on every sheet. The masking tape would be on the top so it wouldnt see any glue.

That just leaves the issue of paper thickness vs width to get the desired tube wall thickness.

Edited October 2, 2014 by Col

[dagabu]

Why not follow industry and cut the sheets after they are glued?

[Maserface]

Read it again, dagabu. He implied that a roller with glue applicator longer than 12" wouldnt be as cheap/easy to build-

[Col]

Why not follow industry and cut the sheets after they are glued?

because then you`d need a glue machine as wide as the roll

[Maserface]

well, not the roll, just as long as the tube you want to roll. remember that the paper has to turn to get the correct grain direction.

[Col]

The paper comes off the roll in the machine direction but the tube is rolled in the cross direction. The commercial machines glue the full roll width and where they cut it off that becomes the tube length. For example, a 4ft wide roll would be glued and cut at 2ft if they wanted 2ft tubes, the 4ft width gets rolled onto the mandrel. We have 2 choices, cut the paper in strips (across the width of the roll) and feed them through the glue machine in their cross direction, or leave the roll intact (full width) and feed it through the glue machine in the machine direction. We trade making the wider glue machine for a narrow glue machine but we`ll still need a full roll width paper cutter either way

 

Edited October 2, 2014 by Col

[dagabu]

Wait... Why 12"? Just because that was a suggestion does not a rule make.

 

If you want a 32" long tube, use a 32" long conveyor tube for the glue rollers. Get a length of shrink tube and a hot air gun, coat the one, two, three coating tubes, arrange them to meet any of the roll coater configurations you wish, put a double roll (wallpaper) pan under the pick up roller and go to town!

 

Good reply Col, that's what I was getting at.

[Maserface]

Nobody said it was a rule, just a suggestion, 12"-15" would be much more feasible. I personally dont plan on building an automated tube roller, I dont have the space to deal with big sheets of paper. 15" would be plenty easy enough to cut and splice together by hand (as Col suggests) and put through a 15" glue applicator and rolled.

 

Roll width would determine wall thickness, and Litin Paper sells many different widths of paper- almost like it was meant to be

[dagabu]

A pull through system with bottom metering would be as easy as making the tube roller.

[Bobosan]

I figure several folks are going to be working on some type homebrew roller system using suggestions and methods talked about here and elsewhere. It would be interesting to see all the designs we come up with to see what works and what doesn't to improve our designs.

 

IMHO, the mechanics of the roller system should be arrived at first, then on to other issues like adhesives and paper. I think mkn has made a nice head start on the mechanics with improvements suggested by others.

[schroedinger]

Btw why not just use virgin paper that comes in sheets of the right size?

[dagabu]

Btw why not just use virgin paper that comes in sheets of the right size?

 

Do you have a source?

[schroedinger]

In the EU yes, but not in the US.

[Col]

Be sure to ask which way the sheets have been cut from the roll, the technical terminology is grain long and grain short (nothing to do with rice). Virgin kraft thicknesses are very limited compared to imitation kraft and thats the main problem. You have to resort to nept tactics and roll multiple sheets at once to get the wall thickness.

The glue machine will need to be gear driven (like the tapofix) or chain driven in the case of conveyor rollers. The pickup roller will be immersed in the glue so a standard conveyor roller cant be used as the bearings wont be happy.

Edited October 2, 2014 by Col

[MrB]

Virgin kraft thicknesses are very limited compared to imitation kraft and thats the main problem. You have to resort to nept tactics and roll multiple sheets at once to get the wall thickness.

I know i saw something of a conversion chart somewhere, but i cant find it anymore. Anyway, i got access to 40, 45,60, and 80 gram weight virgin craft. 40 & 80 on rolls between 20,(40gram only) 57 and up to 150cm wide rolls. The 45 & 60 gram stuff is precut, and very limited sizes. They might accommodate custom sizes, but i suppose that makes the price go up. Currently it's about 3.5 USD / kilo. For single rolls / packs, and drops to 2.75 or so for 5 rolls/packs.

Now, most the numbers might be worthless, especially prices, since it's not reasonable to ship it stateside. But... Would it perhaps be a better move to use the lighter (thinner) paper, wider or multiple sheets to build sufficient thickness, hoping for a stronger tube?

Also, using a less wide roll as the source, should let one alter the total "width" of the paper when rolling, to accommodate for multiple tube sizes, while still ending up at the right, or close to, wall thickness.

(having proper wall thicknesses numbers for different ID tubes should let one calculate how wide strips one need to use...)

 

The glue machine will need to be gear driven (like the tapofix) or chain driven in the case of conveyor rollers. The pickup roller will be immersed in the glue so a standard conveyor roller cant be used as the bearings wont be happy.

Easy enough to fix i suppose. There is always the possibility of using open ceramic bearings. They wash out just as well as the rest of the machine, wont rust, and can be replaced quite easily if they ever do get glued stuck. Of course, being ceramic, you could just slowly heat them until the glue gives up, and let them cool down slowly again. They don't like rapid temp changes, or shock, but then again, what bearings do. Only thing is... I don't know how hard, if at all possible, it is to get at the bearings in a conveyor roller, or if they can be easily cleaned once replaced with ones that stand the cleaning.

 

At least once in place they wont need lubrication, the glue should do just fine.

B!

[Col]

The best roller type for the glue pickup and doctor/metering roller are ones with flat ends and solid fixed shafts, then you can put the bearings in the frame and the drive gears or chain/sprockets outside the frame. I would go for the thickest virgin kraft paper you can get to minimise the amount of cutting and gluing. Then choose a roll width (or two) that, when multiplied by a reasonable number of plies (5 or less) will give you the desired wall thickness. For larger id tubes, the wider the roll is.. the better. The paper width, thickness and number of plies dictate the number of turns required. Taken to the extreme, 1 turn of 1/4" thick paper (maybe 57 plies of 90gsm) may be enough for a 1/4" wall tube in theory but it wouldnt be much good even if you managed to roll it

[dagabu]

In the EU yes, but not in the US.

 

 

Be sure to ask which way the sheets have been cut from the roll, the technical terminology is grain long and grain short (nothing to do with rice). Virgin kraft thicknesses are very limited compared to imitation kraft and thats the main problem. You have to resort to nept tactics and roll multiple sheets at once to get the wall thickness.

The glue machine will need to be gear driven (like the tapofix) or chain driven in the case of conveyor rollers. The pickup roller will be immersed in the glue so a standard conveyor roller cant be used as the bearings wont be happy.

 

If the sheets are square cut, you will see the grain just looking at them, it's pretty obvious on most virgin.

[dagabu]

I know i saw something of a conversion chart somewhere, but i cant find it anymore. Anyway, i got access to 40, 45,60, and 80 gram weight virgin craft. 40 & 80 on rolls between 20,(40gram only) 57 and up to 150cm wide rolls. The 45 & 60 gram stuff is precut, and very limited sizes. They might accommodate custom sizes, but i suppose that makes the price go up. Currently it's about 3.5 USD / kilo. For single rolls / packs, and drops to 2.75 or so for 5 rolls/packs.

Now, most the numbers might be worthless, especially prices, since it's not reasonable to ship it stateside. But... Would it perhaps be a better move to use the lighter (thinner) paper, wider or multiple sheets to build sufficient thickness, hoping for a stronger tube?

Also, using a less wide roll as the source, should let one alter the total "width" of the paper when rolling, to accommodate for multiple tube sizes, while still ending up at the right, or close to, wall thickness.

(having proper wall thicknesses numbers for different ID tubes should let one calculate how wide strips one need to use...)

 

Easy enough to fix i suppose. There is always the possibility of using open ceramic bearings. They wash out just as well as the rest of the machine, wont rust, and can be replaced quite easily if they ever do get glued stuck. Of course, being ceramic, you could just slowly heat them until the glue gives up, and let them cool down slowly again. They don't like rapid temp changes, or shock, but then again, what bearings do. Only thing is... I don't know how hard, if at all possible, it is to get at the bearings in a conveyor roller, or if they can be easily cleaned once replaced with ones that stand the cleaning.

 

At least once in place they wont need lubrication, the glue should do just fine.

B!

 

Delrin would work too if the speeds are low.

[Col]

 

 

 

If the sheets are square cut, you will see the grain just looking at them, it's pretty obvious on most virgin.

Hard to tell if you buy it online as the pics are usually low res or generic. They provide the dimensions but not the grain direction as for normal purposes it wouldnt matter much. Precut sheets work out a fair bit more expensive than buying a roll so you dont want the grain running in the wrong direction.

[MrB]

Precut sheets work out a fair bit more expensive than buying a roll so you dont want the grain running in the wrong direction.

Thats what i expected, but at least from my sources that seams not to be the case.it's about 3.5 USD/ kilo regardless of format and paper thickness, and drops by 25% if you buy 5+ rolls/packs. But the squares could turn out to be useless if the grain goes in the wrong direction, so one should know before hand.

B!

[dagabu]

Guys, the grain CANNOT run the wrong direction in a square cut sheet! The grain will run BOTH directions, turn the sheet 90° and it will run the right way if it is running horizontal when you pick it up. Have you never held kraft paper before?

[Col]

you`re right dag, it doesnt matter with squares

i was talking about rectangles (square cut registered as 90 deg corners in my mind for some reason lol) if you can handle a 4ft square you`d be better off buying a 4ft roll

Edited October 3, 2014 by Col

[dagabu]

Gotcha! Didn't see that, my apologies.