What is the best glue for cardboard/paper tubes rolling

[Col]

If the mandrel takes off at speed, the paper can get left behind or skewed if it only catches on one side. Its plain sailing once you have the first turn locked in place. The you tube machine uses the foldover method for the first turn which is the easiest option but its better if you can run the paper straight onto the mandrel. Getting the leading edge of the paper to tuck into the nip isnt as esy as it seems and prolly the reason why most folks go for the foldback method.

[dagabu]

I have a slitter blade that will cut a start notch into the mandrel, it's 0.05mm thick. The tube will be hand wound until it overlaps then a foot pedal rheostat will control the drill speed. Burnishing will likely be the only high speed operation.

 

Once I get the 8" wide strips working well, I will go to 16" wide strips then the full 24" wide.

 

Looking at shrinkage, it look as if I need to make the mandrel a full 10 thousandths larger than the 0.75" rammers. 7/8" stock will turn down nicely and I can start large, working my way down to the ideal size.

[Col]

A 0.05" slot isnt much of a target and it will still create a tab I have some slitting saws converted into circular knives but no mill so i couldnt cut a slot even if i needed one.

Infeeding a 2ft wide sheet of kraft is easy enough. As long as the front edge is square it should track straight. I prefer calendered paper which are more rigid and easier to handle/position. Single sheets work but its tricky to get the alignment spot on

 

[dagabu]

0.05 mm is purposeful, it is as small as I can go and the sharp angle will indeed tab the paper but the slitter is only going 2mm into the mandrel so the tab is inconsequential. Alignment is going to be the hardest part but with 90 degree straight cuts, it should be manageable.

 

If not, I will slit it deeper or use a 1.5 mm slitter and set a lead in strip to grab the paper at 270 degrees.

[NeighborJ]

Has anyone experimented with adding a few drops of dish detergent to your glue? I'm theorizing it may help to allow calendered sheets to slide allong each other as they are rolled to prevent the delamination issues.

[Col]

Its worth a try. I think the tricky part will be getting the paper to form a clean 2mm bend without pulling it out of the slot

The dishsoap would act as a surfactant which would help with surface tension, not sure if it would be effective as a lubricant

Edited December 21, 2018 by Col

[dagabu]

Not a problem keeping the paper in the slit, run the mill down so that the angle into the mandrel is at an angle so the paper goes in and does about 200 degree turn to capture it. .5 mm is tight enough to where it won't pull out and it's sharp enough to grab the edge of the paper.

[Col]

It sounds feasible enough I guess the mandrel will be slid onto the paper from the side so the paper has no option but to go into the slot?.

Here`s a pic of where the paper sits in relation to the mandrel after the paper slides down the board into the nip point. I can usually tell by feel if its in the right place.

 

 

Edited December 21, 2018 by Col

[dagabu]

The plan is to have the mandrel sitting on the bottom two rollers just like the video I shared yesterday and slip the edge into the slit using the roller as a guide. Wind the mandrel a 1/2 turn to lock the paper in and apply the adhesive. Get a few turns slowly then pick it the speed as the paper is pulled onto the mandrel. Finish with a high speed burnishing run.

[Col]

I think you`ll need some way to keep the paper edge flat and level as it heads for the slot. Something like 2 pieces of aluminium flat strip might do it as the paper will be dry, Fix the bottom strip in the right place and hinge the top strip at one end. You can drop the top strip onto the paper which will force it flat and level but still allow the paper to slide through (T6 strip is pretty slick). Once you have the paper locked into the slot, you just hinge the top strip out of the way so it doesnt get covered in glue. The bottom strip will only be in contact with the unglued side of the paper so it will be ok. You might need to prevent the mandrel from turning as one degree of movement could be enough for the paper to miss the slot

[dagabu]

The mandrel will be in that coupler so it wont move. I can also start the paper by hand like I do now and just wind it up in the machine. It is the tight winding I am after, not so much the rest.

[Col]

The mandrel moving wont be issue with that. The slot will work but i think you`ll need something to tame the paper. If you look at the wavy leading edge of the paper in the infeed vid, its hard to imagine that going into a 0.5mm slot without a bit of taming Generally with handrolling, the bigger your hands the better the tube, so for tight windings its a case of getting enough even pressure over as much of the tube area as you can

Are your conveyor rollers male threaded, female threaded or the spring loaded hex type?

Edited December 21, 2018 by Col

[dagabu]

Hollow hex, no spring. They are feed through type.

[Col]

ahh, was hoping they might have round male threaded axles, which would give you a few more options.

[dagabu]

I found my mix!!!!!!!!!!!!!!!

 

50/50 PVA mixed with 50/50 Roman 880. Burst testing comes tomorrow but my ID & OD are working perfectly, no delamination issues.

 

Here is my "high-tech dryer".

 

[Col]

The dryer looks good to me, are the tubes glued to the baseboard? Starch and pva both bring something different to the party, i use an 80/20 wheatstarch / pva mix in the shell pasting machine.The gravy retest came in at 60% solids compared to the original 58% so it hasnt changed by much over 18mths. Bottle cap weighs 1.3g

 

 

I did a test to see how much water evaporated from a tube made with three 3ft strips of kraft 200mm wide. The glue was rollered on (thin film) and the sheets were handrolled one after another with no deliberate drying time between sheets. The total evaporative loss came in at 10.9g, or around 3.6g of water per 3ft x 200mm sheet. I forgot to oven dry the paper beforehand (doh) so the 10.9g includes moisture that was already in the paper. I`ll have to check some from the same roll but its typically 7-11%.

Here`s the tube, ends cut with a 24tpi saw

 

 

Edited December 22, 2018 by Col

[Col]

Merry christmas to all

quick update, i tested some paper from the same roll of kraft and the moisture content is about 8%. The revised numbers are 2.94g of the water came from the paper and 7.96g of water came from the glue.

I also discovered the rolling machine has a novel feature. its capable of looping a single sheet of paper and automatically reloading it as it exits without any human intervention, just gravity. Its not a useful feature in itself, but it shows how easy it can load the sheet. The sheet in the vid is 2ft wide by 16" long with a 15.3mm mandrel installed. After 10 complete loops (13.3ft) there is no noticable change in the alignment even with a dirty great hump in the paper

 

Edited December 26, 2018 by Col

[dagabu]

Kickin' it with the new glue mix! The ones that didn't lay flat after rolling them got cut in half for cohete rockets.

 

[Col]

you`ve been busy The ones that dont get by quality control are always useful for something. Do some have the internal tab from the slotted mandrel or is it just where they`ve been cut.

[dagabu]

No machine yet, all hand rolled. The tabs will get glued down before using them, the three or four with the extra tabs were mistakes where I didnt apply the glue far enough back to stick them down. The newer ones are solid all the way through.

 

8800 LPI without bursting.

[Col]

After handrolling well over 1000ft of paper you should get a medal for patience The easiest way i`ve found to deal with the dry margin on the paper is to cut a strip of 6 mil poly the same width as the dry margin and tape it to the gluing board on 3 sides. You just slide the paper under the poly and glue it up without any measuring and marking

[dagabu]

No need, my rolling board has lines drawn on the surface that tell me where to stop with the roller when applying glue. Works very well, no issues.

[Col]

The edge of the poly is my line i start with the roller just on the poly so it creates the line as it rolls onto the paper. If i used marks on the board, with my eyes the chance of a straight line is more luck than judgement

[dagabu]

....... If i used marks on the board, with my eyes the chance of a straight line is more luck than judgement

 

I hear you!

[Col]

The mandrel will be pinched between three rollers, it will free float, the bottom two rollers will be static and will almost touch (I will be able to roll 3/8" up to 1" with this layout) and the third will be hinged with long arms and have a handle allowing down-force to be applied at will. I will play with weights on the handle to see if I can find the perfect compression.

I think you`ll find you can use more weight/downforce for the 1st strip, less for the 2nd strip and more for the 3rd but still less than what you used for the 1st strip The reasoning is the 3 roller layout is similar to placing the tube into a vee block and applying a downward force directly to the top of the tube. The mandrel will provide mega support during the 1st strip but it prolly wont fit back into the tube for the 2nd and 3rd strips due to the shrinkage if you are drying the tube between each strip. If you use too much force, the tube could deform (aka flatten) as you`ve only got the strength of the tube wall, not a solid mandrel to prevent it bowing out.. The 2nd strip is the one to watch because thats where you`ll have the thinnest wall. After the 2 strip is dry you`ll have more wall thickness so you can get way with using more force.

Edited December 28, 2018 by Col