WASP

[Algenco]

You know, this tape that is used by the WASP can be applied by hand. This is what I do. It is a comfortable medium between cutting and breaking in strips of paper, and dropping the money on a WASP. There is another method a few of the other European pyros have posted that I believe they call the Liuyang method. They brush one side of a large sheet of paper with paste or glue and fold it up on itself. These wetted strips can be stored for a day or so I believe in a plastic bag. It can be cut into strips from there with a guillotine type cutter or scissors, peeled apart, and applied like normal strips. I've never tried it, but it seems like it should work pretty well.

 

 

Mumbles, that the method I use, makes for hard, smooth pasted layer

[warthog]

http://www.pyroguide...strip_method%29

 

Thank you Arthur, one last request. A rule as to n umber of layers to paste for different diameter shells. Or is this more governed by the desired diameter at the end of the process and therefore essentially learned as you do them and get more used to things. I am just looking for some sort of idea from which I can go as I do.

 

Thanks again!

[Potassiumchlorate]

3 layers for every inch of the shell diameter is a rule of thumb, though you can cut down a bit on that if you use H3 or any other really powerful burst. So for a 5" with BP, you should use 15 layers, but if you use H3 or KP you could very well go down to 12 layers.

[Arthur]

My hand technique seems unique but it works so I'll share it, whether it works for you...

 

After simply securing the hemis together with gummed tape.

Using 19mm gummed tape with the hemi joint as the equator, paste with short strips from "tropic of capricorn to tropic of cancer" progressing only about 3mm each strip, and laying the strips at about 45 degrees to the equator.

So this effectively puts six layers on per turn.

Then repeat this with strips on the other diagonal from the "Arctic circle to the Antarctic circle"

Then repeat this with strips which start beside the fuse and finish at the side of the other pole. - this is the neat and tidy layer!

If you want a string loop then place it opposite the fuse before the last layer which looks better and is stronger or tack it on later with more paper tape.

 

This method is easily done one handed while holding the product and has enough strength at all points to break OK, without building egg shaped at the poles

 

cf http://en.wikipedia.org/wiki/Tropics_of_Cancer_and_Capricorn

 

PS has anyone any experience of using really thick paper? I have some rolls of Colorama photo studio background paper which is about 1.5mm thick. If this was soaked in paste would it be worth say three or four pasted layers or would it not work? I could have some cute shades of shells!

Edited November 13, 2011 by Arthur

[Potassiumchlorate]

I actually use a similar method, though with gummed tape all the time, but I can't say that it goes quickly. I put a lot of time in making the strips eqaully long, getting them just wet enough and not too much, making sure that they adhere well etc. Edited November 13, 2011 by Potassiumchlorate

[FREAKYDUTCHMEN]

How do you manage to paste 17 layers in 45 minutes to an hour? You must be very skilled.

Actually I find this quite slow for 17 layers on a 6" shell.

 

I never paste more than 5 layers on a 6" because I like to use flashpowder.

[Potassiumchlorate]

Actually I find this quite slow for 17 layers on a 6" shell.

 

I never paste more than 5 layers on a 6" because I like to use flashpowder.

 

Hm. BP on rice hulls and flash to lace it with? What BP/carrier ratio and how much flash? H3 is cheap and simple, but BP with a few grams of flash would be cheaper and perhaps more powerful.

[Algenco]

I get 5-6 layers on a 6" using pasted 50# kraft, any more and they won't fit

[FREAKYDUTCHMEN]

Normally there would be about 1cm space left between shell and mortar wall, more or less. 5 or 20 layers, doesn't make a lot difference.

 

H3 doesn't ask lots of pasting if I remember correctly.

[50AE]

Storing wet paper is a problem if one must use recycled one. Recycled kraft must not be allowed to soak water completely at all costs, otherwise it will become very sensitive to ripping and it it will be a PITA to work with.

Yes, cutting the paper is the most consuming parts. With time, you get the trick and start to paste faster and faster. You just need experience and a little self confidence.

I remember when it took me about an hour to paste my first 3" shell, but now I apply 14 layers on a 5" shell for about 50 minutes including the paper cutting.

I fold long sheets of paper, wet them in glue and cut them in strips - the longer the strip is, the more efficient the pasting is.

When I have to paste many shells, I'm dreaming for an infinite length of strip sometimes

[dagabu]

Normally there would be about 1cm space left between shell and mortar wall, more or less. 5 or 20 layers, doesn't make a lot difference.

 

H3 doesn't ask lots of pasting if I remember correctly.

 

The standard is 5% of the shell diameter for all sizes.

 

-dag

[warthog]

Thanks to all of you! 5% of the diameter is a good standard for me to use. I appreciate all the help

[Potassiumchlorate]

We discussed the diameter shell/mortar on the UKPS forum. Due to the low density of a firework shell it benefits from not fitting tightly into the mortar, as opposed to a bullet in a firearm. The "pillar" of air pushes the shell downwards, but the gasses at the launch, push away a good part of the "pillar".

 

Shell diameter²/mortar diameter²<=0.5 according to Shimizu.

[Mumbles]

That ratio doesn't seem right. It should at least be greater than or equal to .5. 0.5 still seems extremely low. I'd put that number around .9 or .95.

[californiapyro]

yeah, take a small shell for instance, 1.5 inch. if the mortar is 2 inches, then it would be 2.25/4 which is over .5, and certainly the mortar is too large...

[Peret]

I thought Shimizu said the ratio of diameters should be 0.95, giving a ratio of areas of 0.9. When I have a moment I'll look it up. That's what I always worked to, anyway.

[Potassiumchlorate]

Sorry, I was wrong. It was 3:11 in the morning here when posting that, though. 0.5 fails. 0.9 is good. That was what Shimizu said. Have a diagram here.

[warthog]

And I now have the same diagram for reference, Thanks KClO₃!

 

I have also been reading up in my copy of FAST which I should have done in the first place.

Edited November 15, 2011 by warthog

[Arthur]

Your shell should slide softly to the bottom of the mortar with some air resistance to damp the rate of fall. It may even take a bit of a push but not much! If your shell drops to the bottom too quickly then it may not reach it's full potential height.

[warthog]

I did want to note I got a reply from Precious Pyro concerning their pasting machine. I asked for a picture of the machine or a description f how it works and was told he would not show a picture or tell me much about it for fear I wold duplicate it myself and not buy his machine. I was simply told it was hand cranked and used masking tape instead f gummed kraft so you didn't have to wait for the shell to dry.

 

I told him thank you for the reply and said that if he ever takes them to an event for people to buy and see, I would then make my decision. He told me he won't do this as again, the design is a secret, if I wanted one I could buy it. I asked him what this was about if it was patented and he told me he refuses to patent things because then the plans become public knowledge. I dunno what to think about him really.

[Mumbles]

It sounds like the video on the Ricardo Caballer site. Paster Video I really can't tell if it's foot powered or has a motor, but it appears to be going pretty quick. I've seen a similar thing being used on canister shells as well, but can't find the video.

 

These are really designed for the spanish style of building shells. This involves plastic casings usually, and a lot of flash powder. Those methods are somewhat of a departure from the "normal" methods we may hear about primarily from japan or china. I really don't know many people with a thorough knowledge or understanding of how they're made. You hear bits and pieces, but far from enough to fully piece it together.

[Peret]

I told him thank you for the reply and said that if he ever takes them to an event for people to buy and see, I would then make my decision. He told me he won't do this as again, the design is a secret, if I wanted one I could buy it. I asked him what this was about if it was patented and he told me he refuses to patent things because then the plans become public knowledge. I dunno what to think about him really.

That's a half-witted excuse. If he even ever sells one, the secret is out! More likely he's wary of the WASP patent. You don't need to actually infringe on a patent to go bankrupt defending yourself against a frivolous law suit.

[garyrapp55]

I just wish I knew someone who had a WASP. I could at least offer to pay per shell to paste at their leisure. Pasting 10-15 shells takes me all day. I have a job and two toddlers so obviously I don't get to make nearly as many shells as I'd like.

[Potassiumchlorate]

I know two guys, but they live in Europe, so not much help for you there.

 

But they are very satisfied with the machine.

[Bcorso85]

Its a great machine I love it. I paste a 3 inch shell in 2 minutes 23 seconds.and its dried in three hours. I didn't go to precious pyro though.