Jump to content
APC Forum

Pumping stars with pneumatic cylinder


Recommended Posts

Posted

This is my latest tool in my workshop. The star hight can be adjusted from 16 to 24mm, with a simple turn.

I pumped 3kg of 18mm stars in 45min.

 

http://www.pyrobin.com/files/pumping%20station%203.jpg

 

http://www.pyrobin.com/files/pumping%20station%202.jpg

 

Video of tooling in action: http://www.pyrobin.com/files/pumping%20station%204.3gp

Posted
Very cool looking. How is the consistency between composition density and weight between each comet? It seems like it'd be a little hard to control exactly how much composition gets into the tooling each time.
Posted

This is my latest tool in my workshop. The star hight can be adjusted from 16 to 24mm, with a simple turn.

I pumped 3kg of 18mm stars in 45min.

 

http://www.pyrobin.com/files/pumping%20station%203.jpg

 

http://www.pyrobin.com/files/pumping%20station%202.jpg

 

Video of tooling in action: http://www.pyrobin.c...station%204.3gp

 

 

i wish i knew how to make things like this been thinking of getting a metal lathe great job on this mate add a couple more tubes your in production

Posted

Very cool looking. How is the consistency between composition density and weight between each comet? It seems like it'd be a little hard to control exactly how much composition gets into the tooling each time.

I took 10 stars and weigh them, the weight of single star was between 6,1 and 6,3g so I think that's good enough. I constantly add composition in to the box and compress it a little, so that the pump gets almost the same amount of star composition every time.

Posted
Great machine Zmuro. How much pressure is there involved, and what about the percentage moisture in the composition?
Posted

I like the idea! Have a look at a "Tablet Press" on ebay, the single punch machines can easily press out a tablet (star!) per second at low moisture content. Now if your machining skills are up to grade the you should be able to make one for a useful range of star sizes.

 

BIG CAVEAT these things are often "cash on collection" with "smiley face dies" for the illegal drug trade, so deals may come with dog and dog handler attached.

Posted

Nice tool, I have a 100mm bore cylinder destined for a similar purpose when i get round to it.

I like your automatic star ejection feature, i`d be tempted to use a sloping ramp (operated by the piston motion) to direct the star into a tub :)

Posted

Great machine Zmuro. How much pressure is there involved, and what about the percentage moisture in the composition?

I'm using 50mm ID cylinder and 7 to 8 bar of pressure so that gives you 137-157 kg of force on a single star. I also have 80mm ID cylinder which will give 400 kg of force at 8 bar. In the future I will make multi star pump which will pump 8 or more stars (depending on star size) at once.

Posted (edited)
Nice start to a useful machine. Please look at the method of extracting the stars, anything is better than putting your hand under a press tool. How about a timed air jet to blow the star onto a chute. Edited by Arthur
Posted

I like the idea! Have a look at a "Tablet Press" on ebay, the single punch machines can easily press out a tablet (star!) per second at low moisture content. Now if your machining skills are up to grade the you should be able to make one for a useful range of star sizes.

 

BIG CAVEAT these things are often "cash on collection" with "smiley face dies" for the illegal drug trade, so deals may come with dog and dog handler attached.

 

Dammit. You had me searching the web for an hour. I would kill to have one of those hand cranked presses for making 1/4" stars. But they are very expensive and seemingly hard to find.

Posted

I'm using 50mm ID cylinder and 7 to 8 bar of pressure so that gives you 137-157 kg of force on a single star. I also have 80mm ID cylinder which will give 400 kg of force at 8 bar. In the future I will make multi star pump which will pump 8 or more stars (depending on star size) at once.

 

A multi star pump will make it a lot cheaper to run. According to the cylinder specsheet, i`d need about 2000L (70 cubic feet) of air (40mm travel) to press 3kg of comp one star at a time.

  • 8 months later...
Posted (edited)

My new 30 mm crossette tool and multiple star pumps (8, 11, 14, 16 mm) made from stainless steel.

 

The cross for crossette was drawn in Solidworks and then made on 5-axis cnc router.

 

post-1965-0-88418900-1344354839_thumb.jpg

 

post-1965-0-40277500-1344354874_thumb.jpg

Edited by Zmuro
  • Like 1
Posted

Good job Zmuro!

How can you remove the stars with this tools?

Posted

Good job Zmuro!

How can you remove the stars with this tools?

 

They auto eject, look for the spring in the middle.

 

Nice tooling!

 

 

-dag

Posted
Yeah his original video shows how easy his autoeject works. They just come out in his hand. This is awesome.
  • 5 years later...
Posted

Nice tool, I have a 100mm bore cylinder destined for a similar purpose when i get round to it.

I like your automatic star ejection feature, i`d be tempted to use a sloping ramp (operated by the piston motion) to direct the star into a tub 2smile.gif

how is the ejection of the star controlled ?

are there 2 tubes one to fill/compress the powder and an inner one to eject it ?

Posted
Dave, if you look at the picture you will see an aluminum bracket clamped to the press support. It is a catch for a bolt inside the pump. When the pump retracts the bolt makes contact with the brace and slides in a slot to eject the comet.
  • Like 1
Posted

Here`s the arrangement i used to mod a 1T arbour press ram.

post-10522-0-07260300-1513705031_thumb.jpg

 

 

  • 7 months later...
Posted
This is exactly what I am working on.
×
×
  • Create New...