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Looking for a 20000 - 30000 RPM Drill powered by pneumatic 2

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What do you what the tool to do?
How will you mount the tool, or will it be hand-held?
Most tools will be rated for 22,000 to 24,000 rpm (air-driven motors or grinder or polishing tools for example) with 1/4 inch shafts.
Do you really - really want to look for 30,000 rpm tooling?
 
6 mm in rubber at 30,000 rpm??
Melting will be easy.
Drilling? Easy once.
Not so easy the next 44 times.

Ouch.

How deep?
How "stiff" a rubber compound are you trying to go through?
How will you "pull" your chips (debris actually) out of the hole way from the tip of the drill to prevent seizing of the very tiny drill with loose rubber strings as they bind and wrap around the drill shank when it tries to withdrawal?
How will you cool the drill bit between each hole to prevent "melting" the rubber and "drilling" the rubber?

can you use a drill drill with an air supply hole down past the shank to "blow" the accumulating rubber strings and debris out of the hole BEFORE you try pulling the drill up and out of every hole?
 
it take 1.5 mm thickness
and i have try it with electrical drill doesn't melt at all
it shape like pipe and pneumatic will push the chips out from one side
 
Sharpen a 6mm tube in the end of a 250+ W soldering iron.

Should melt through in a few seconds.

It will probably take longer to clean the tip than make the hole.


OR

Sharpen a 6mm tube in a pneumatic die grinder.

It will be difficult to remove the divots from inside the cutter, but less of a mess than turning all the removed material into dust or smoke.



Mike Halloran
Pembroke Pines, FL, USA
 
The problem with machining rubber is its flexibility and resistance to transfering heat. In the rubber industry they use liquid nitrogen or CO2 to freeze the material to harden it and then machine it quickly before it looses that hardness. A polished surface finish on cutting edges is crucial to prevent/reduce pick-up and/or frictional heat and lubrication with suds (oil and water or just water) is essential.

Some examples from my experience:
[ul]
[li]A circular hole in room temperature material - a simple tube with a polished chamfered inside end will produce a clean hole but result in difficulty in removing the waste material due to its compression by the tube's wall thickness (therefore thin tubes are best). A chamfered edge on a circular part (e.g. a sealing edge) can be produced by rotating the part at the highest speed available (>1,000 rpm) and "machining" with a thin blade (e.g. scalpel) with plenty of water. The blade has to be pushed axially into the material maintain its strength (as a knife cuts bread) and a suitable holder is essential.[/li]
[li]A shaped hole in a block/sheet of material will depend on the complexity of the shape and the thickness of the material and/or hole as well as whether the ability to freeze the material is available. Reasonably complex shapes in thin materials can be produced using a knife tool (a thin flexible blade fitted into a board of timber or stiff plastic which has been routed with the required shape using a cutter of the same diameter as the blade thickness and using the waste/inner piece of the board to lock the blade in place - more details available if required) and a press to punch the shape into the sheet material against a sheet of board/plastic (knife tools are capable of 1000s of parts when set up correctly). If the material is thick then freezing is the best solution but using CNC rather than by hand due to the lack of rigidity and control that hand machining produces.[/li]
[li]If the volume justifies some investment then a milling machine modified to take a high speed pneumatic motor produces excellent results in many types of soft materials (I have machined very complex shapes in thin pure aluminium at 80,000 rpm using 3 mm diameter micro-grain carbide cutters in one-piece flow lines where tact time was critical and quality paramount)[/li]
[/ul]

I hope that helps in general, if not with your specific requirement.
 
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