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Pneumatic multiple star pump


Zmuro

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This is my improved multiple star pump. I have various sizes of these pumps. The one in the video is 10mm. I'm using 80mm ID air cylinder.

 

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80 mm diam. = 50 square cm.

50 square cm * 8 bar = about 400 kgf for your air cylinder. Enough for crosettes, small comets etc. Nice !

 

This tool of yours can easily replace a star plate and be faster at it....

 

Is your compressor a 25l one?

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Cool machine.

How are the stars kept at consistent size and density?

I'm also curious about this.
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Actually if you push down the plunger and sleeve at the same time, you will have the same ammount of comp in every pump every time (ar least quite close). Then press down the plunger if the sleeve hits the bottom to compress the comp.

Biggest problem should be that the the comp can start to compress in the tub, if it does that it will need to be screened again.

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Explain to me how they wouldnt continue to get smaller and smaller?

Refill the tub :- )

 

In reality i don't think it's much of a problem. As long as they are longer then they are wide, you'd get the same burn time, and even with a mm or so of sizing differences, your not going to be able to tell one from another when in the sky. The only time i see it making a difference is when your building your shell, and stacking 10 of these on top of one and other in rows along the walls of a shell, the chance of getting 10 long in one row, and 10 short in another, so that the difference turns out to be an issue, seams remote.

There will be a slightly larger variance in size then from a star-plate, but if you want perfect stars you need to go further then plates or pumps like this anyway, and aim for something that pumps the star, and then size it by shaving of the excess, and finally drops the star. Entirely possible, but i don't know anyone that does it. Go-getters, and crosetts, sure. Stars? No really. Sizing stars is more typically done with rolled stars, which is a somewhat more involved process anyway. (And one i prefer. I just suck at sizing the stars. I should build a roller based sizer.)

B!

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All stars are almost the same size. You must add the composition quite often. It's quite faster than pumping with star plates, maybe stars are more dense and uniform, but that's not an isue for me. I think my youtube videos speak for themself.

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When the open part of the tube fills, it cannot fill any more, the extra hangs off the bottom, a knife plate (in production) strikes the extra off and the pumps eject the stars.

 

The really interesting thing about pumped stars is that even a long pumped star will burn out at almost the exactly the same time! Don't believe me? Try it.

 

The star is thinner than it is long, the fire burns all surfaces and the star (lets say 10mm wide for argument sake) so the greatest amount of comp that has to burn is 5MM no matter how long the star is.

 

Neat huh?

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When the open part of the tube fills, it cannot fill any more, the extra hangs off the bottom, a knife plate (in production) strikes the extra off and the pumps eject the stars.

Neat. Automatic sizing. As long as the tubes don't hit the bottom they should produce consistent stars. Saves on composition. If the tubes hit the bottom, then there might be a fill issue generating lower density stars.

 

The really interesting thing about pumped stars is that even a long pumped star will burn out at almost the exactly the same time! Don't believe me? Try it.

 

The star is thinner than it is long, the fire burns all surfaces and the star (lets say 10mm wide for argument sake) so the greatest amount of comp that has to burn is 5MM no matter how long the star is.

Muahahah. Beat ya to it :- )

 

In reality i don't think it's much of a problem. As long as they are longer then they are wide, you'd get the same burn time, and even with a mm or so of sizing differences, your not going to be able to tell one from another when in the sky.

 

Fun an giggles, all the same. Longer pumped stars just means more light. At some point the stars start looking weird in the sky due to looking more like burning rods, then round balls of fire, but if the variations are minor, you wont be able to see it. I mean, people regularly pump stars that are 2x as long as they are wide, without issues.

B!

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Well, that makes sense and all, and I can see how the stars would be easy to get to a uniform size. I was really thinking more about the density of each star. I suppose it's no different than using a regular star plate in that regard though. They may not all be exactly identical, but when you really get down to it, close enough is close enough. It's a very cool machine Zmuro. Great job. Edited by BurritoBandito
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any way you look at it, it beats scoop, ram, eject. scoop, ram, eject. scoop, ram, eject ad infinitum...

 

and yes, zmuro, that is a pretty awesome machine.

Edited by rogeryermaw
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Sweet machine, Zmuro.

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heh, alright then, go out of your way to produce inconsistent stars! You say you dont mind, thats fine!

As for me, ill be rolling and pumping stars with a star plate

Edited by Maserface
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heh, alright then, go out of your way to produce inconsistent stars! You say you dont mind, thats fine!

As for me, ill be rolling and pumping stars with a star plate

 

 

 

No, that cant happen, the extra comp sheds off to the side allowing the under-filled pumps to fill and compact. It's near perfect as long as there is room for shedding and enough comp to fill each pump. Here is the proof; Zmuro, weigh all your pumped stars in a batch and see what the weight difference is. The weight will determine the amount of comp. I bet they are as consistent as a plate.

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Unless you're weighing the composition put into each star individually, and pressing an evenly distributed pressure across the whole plate, I think a star plate is going to suffer from the same inconsistency in density. I wasn't trying to imply that this is an issue with Zmuro's machine specifically. I would even go so far as to suggest that his stars are probably more consistent, due to being mechanically pressed with a precise pressure/volume, and I bet that he can turn out a ton of more stars in an equal amount of time, with less effort. He's hardly "going out of his way".
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Building an entire machine to produce one size of stars for me would be going out of my way.

Star plates DO press evenly across the whole plate, and they are then CUT to length, pressed to density, cut to length- voila

 

This machine is certainly servicable, and I havent said otherwise- just merely my own observations. I would never use this machine to press crossettes, or anything for exhibition. Again, thats just me.

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IMHO: Gang pumps with the addition of a striker are the commercial norm, not the exception. Plates with wiper blades for small stars are the norm for production due to automation but not specialty items.

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If I understand correctly he can change out the pumps, so that this machine can be used to make different sizes. Though I may be mistaken.

 

Edit: Maserface, I'm just curious. What method are you using to apply pressure your plates?

Edited by BurritoBandito
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"do you know any show tunes?" :P

How did you know that? Get outta my head!!!

 

I use a press, and I think I know what you are going to ask next.

Seriously, I have no further questions. I wasn't looking for a debate, but was legitimately curious.
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oh alright, yup. just a plain ol harbor freight H-frame press, welded square with a 1/2" blast shield.

 

I have everything but a powerpack for a hydraulic press, waiting for one to come across the classifieds.

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