Need advice on having a prototype made

[Anonymous]

I'm trying to get several prototypes parts made and haven't had any luck. I was hoping someone could point me in the right direction.

The problem is the attached "pot"... which is similar to a double-walled/vacuum sealed tumbler.

The parameters are:

• It needs to be exposed to a flame (without melting. 🙂 )
• Liquids should be consumable from it.
• It's a thin walled object and I've learned that additive/reductive prototyping isn't a good fit for this 
• It's part of a press-fit assembly so making it by hand has proven difficult (8 times and counting)

Top ViewBottom View 

Any suggestions would greatly be appreciated.

Thanks!

Dustin

[lee_sanders]

Hi @Anonymous 

Certainly, not the easiest part to make!

One way could be,

material = aluminum, CNC turning and probably need to use EDM (spark errison\die sinking) 

Op1 - bore, and OD

Op2 - turn as much as possible including groove (using a special grooving tool)

Op3 - EDM the rest of the internal groove

I hope this helps, good luck!

Lee

[RCSDesign]

That is a stamped/die formed part all day.  It being part of a press fit assembly probably means you need more machining after the initial form. 

With that being said that looks expensive as hell to make.  I would approach the problem from another angle and rethink the design unless your volume is going to be in the millions and its worth making specialty tooling for.

[CRANDALLPRECISION]

Press together and weld?

https://a360.co/3esBV2z 

[Anonymous]

Modify joint to have secure and precise connection, make outer and inner parts to have .001 interference fit at joint.

Heat outer part, freeze inner part, assemble and let cool down. 

[CRANDALLPRECISION]

Yeah if you heat it I would go up to .005 interference. This way if parts are slightly warped they won't leak

[Anonymous]

Idea is based on previously done work, actual numbers need to be considered based few factors like material type, precision, intended purpose, function .... etc.

Too much of an interference can result in outer part crack so specifics need to be derived from information I don't have.

[Anonymous]

@Anonymous 

I would take anything like that to my friendly local Metal Spinner, example, if making the part from Aluminium, thin MS steel or thin Stainless Steel he would be asking me for a simple form tool to the size shape of the internal bore of the "Pot", and also a sleeve the size of the gap between the inner and outer walls.

The operation could be a simple spin shape of the inner first, then place the sleeve on the just spun shape and using a larger diameter stop to suit the sleeve a fraction under its diameter then spin the material back along the sleeve and part off.

All done from a single piece of material, modern CNC Spinning Machines are very accurate and I reckon you could achieve the tolerances you need.

So, the two form tools needed would be quick, easy and inexpensive to produce, the spinner guy would probably be able to do those "in house" if you are not able to provide them yourself.

Link to an example CNC Spinning machine

https://www.youtube.com/watch?v=dLr7FTDUpX8

Worth looking such a shop up and running your design by them, can`t hurt.