41 replies to this topic

[Matt]

Hey fella's, I havnt bugged ya's in a little while so i thought i'd do it now
My question is about paper weights, I have always bought 60gsm craft paper on 10m rolls. I always thought it was the same as 60lb paper. I just thought to myself that this probably isnt true so i googled it and I still havn't gotten a straight answer, ive had conversions from 1.5lb to 45lb. Is there anyone on here farmiliar with the converson from gsm to lb? This paper has always worked well for my shells and tubes but this has sparked the question of "could they be better?" as shells require certain weights for best performance yada yada yada. Thanks for any help.

-Matt

[bernie]

If it works, use it. You'll have to fill me in on gsm.

[Matt]

gsm= grams per square meter, not per ream *smacks self in head*

[Edited on 31-7-2003 by Matt]

[bernie]

I wouldn't sweat it. From what I've seen your shells and tubes are top notch. Actually Matt, you should start a thread about tube rolling.

[Matt]

Oh silly me, I searched all over google but it didnt pop into my head that i should search rec.pyrotechnics. Searched in there and i got my answer straight away. divide the gsm by 1.63 to get the equivalent in lb's and likewise times the lb's by 1.63 to get the equivelant in gsm. This might come in handy for anyone out there in the future with the same question.

-Matt

[Matt]

Thanks Bernie! its nice to get a few complement here and there. Speaking of tube rolling. What is your favorite glue? ive always used white pva glue pasted on with a brush then rolled on the former. I was recently thinking about using wheat paste, is this good for strong tubes? I was thinking of using for price (obviously) and the fact that I could cut up lots of strips and put it in a shallow tray full of the paste, that way I could pull out one sheet then rollit, put the tube aside, get another sheet roll it etc etc etc. I figured I could get a heck of a lot more tubes rolled in a shorter time this way. Perhaps I should just thin down some white glue with acetone. uugghhh so many options! But then again this hobby was "founded" on experimentation.

-Matt

[Pyromaster2003]

try wall paper paste.

[smpip]

Matt,
If you water down your PVA (poly vinyl acetate)(using water) and dunk strips as you suggested with the flour glue method, ensure they are wetted, then squeegee off the excess, (hey, I don't have all the answers, put two windsceen wipers face in and wrap an elastic band round each end, not too tight!), then start your production line.
PVA can be watered down until it flows like water and still be effective as a glue, however if you are dry rolling (tut, tut) then the glue needs to be thicker.

[bernie]

Try the wheat paste. Add some PVA to it if you feel the need. I just paste on one side. Never had good success myself with getting the paper all soaking wet. Make a couple samples of each and see what you end up with. Keep notes and spread the good word.

[Matt]

ok. i just made a few (8) tubes with some wheat paste, i soaked the strips for about 10 mins in a small bath of paste, I pulled them out, wiped off the excess glue then put them in a little pile. Got a steel rod (5mm) and rolled the tubes. I must say this way is far easier than my other way. The only downside is that they take a painfully long time to dry. Some people say to cook them in an oven on a very low heat, i might go put some of the tubes in my oven shortly and see what happens. Whilst i was waiting for these to dry I went to rec.pyrotechnics and searched up on rolling tubes with wheat paste and the arguement is that wheat paste dries hard and relatively brittle and that wheat paste is best used for shell casings as they will give more even breaks and that white glue often has different chemicals added to have a small amount of elasticity when dry. So I'm thinking that wheat paste isnt so good for giving good rocket tubes but rather for goos shell casings. Only time will tell. I shall keep you all informed of my findings.

-Matt

[Matt]

Just a little update. I havnt had much success with rocket tubes with this stuff, they tend to split and ripple, they are pretty good for shells though, one note to anyone planning on making wheat past ADD SOME SALT!!!!! FOR THE LOVE OF GOD JUST ADD SOME SALT!!!! the last thing you want is to open up your jar of wheat paste a few days later to find its gone off! no-one on this planet deserved that...... except perhaps sihakket or whatever his name was.

-Matt

[smpip]

Man, that smell will be with you for life:o

[bernie]

Can't even begin to imagine............

The wrinkles(ripples) etc that you describe can be attributed to 'soaking' the paper. The paper stretches unevenly. Best to paste just one side when rolling tubes. Wheat paste is the only way to go when pasting shells.

Did you use flour or wallpaper paste?

[Matt]

wheat paste tubes ripple. i now have a crapload of watered down pva, it works better for rocket tubes.

-Matt

[dfk]

whats the difference between dextrin and soluable glutinous rice starch in stars. can they be switched? and does dextrin work for rolling tubes or not even close?
thanks
marcus