Is sheet metal fabrication the best process for this product?

[deemoss]

Guys, I have a design (see below) that I'd like to sheet metal fabricate. The problem I'm facing is that I can't get a prototype for a reasonable price. The outfits I contacted said they need to create the molds before they can produce a prototype ($7k+). Is SMF the best process for producing this? Is there a way to produce a prototype without committing to the cost of the mold?

Material SS304 1/8"
Length: 8"
Largest curve diameter 3"

Thanks!
Dimos

 

[Philabuster]

For just one part, wire EDM is an option, but it will not be cheap. Cheaper than a forming die though.

 

[memphisjed]

If not stainless fold and beat over wood board. Stainless makes it difficult.
Can fabricate (weld) one up faster and cheaper for quantity in onesie twosee.

 

[swarfless]

Find someone with a press brake who knows how to use it. Looks to me like only two radius tools required, order of ops relatively straight forward. Either develope the blank in the flat first & water jet, Laser or wire cut .. even bandsaw & a file .. then form, OR form up from rectangular blank then shape ends by one of the fore mentioned methods. This for prototype, production method dependent on numbers. For that I'd consider roll-forming lengths of the section & possibly part off parts with a punch press, formed 'arbor' supporting the section, first stroke defines 'nose' of first piece, second stroke defines 'tail' of first & 'nose' of second & so forth. A 'bow-tie' punch & die.

 

[Peter from Holland]

Depending on what accuracy is requiered one could fab something up out of rectangular tubing perhaps ???
Otherwise a welded up mould and muliple steps can bring you a long way
If I would have to do it I would first make the bead on the left Leave it too long to trim
Simple U shaped die and a rod welded to a base
Then the top part. First make it as a U shape with the right radius
U shape and 2 rods welded to a base
Then the big radius with a piece of 2" round
The lower part eighter weld it to the rest or on a folder
It may take a few tries And a decent press

Peter

 

[BT Fabrication]

anyone that is any good with a press brake should be able to do that, might take multiple bends to get the radius, but it will proove out the product for it.
it is definately a bit of a pain of a design, but entirely doable.

 

[swarfless]

Peter's comments brought me back to reality .. for a visual, tactile prototype, in my retirement shop (now) I'd fab it up from sections of tubing or pipe & flat strip, full butt-welds or silver solder, or just tack welds if sufficient for 'function' of testing the idea.

 

[Strostkovy]

Doesn't look like a good press brake job to me. I think you'd need to bottom bend the 180 degree bend on the left since there isn't enough material to use a conventional V die. You'd need a very specific size gooseneck punch you would have to order custom. The large radius tooling is cheap so that's not an issue.
It's doable but it's not worth bothering with without a lot of money behind it.

 

[Seesecurity]

You could get it 3d printed in SS, might be the cheapest option depending on the required accuracy.

 

[BarnFab]

You can make that on a press brake easy enough with one custom form tool or two if you didn't own a radius die.

 

[Strostkovy]

How are you guys who suggest using a press brake intending on forming the 180 degree bend in the top left of the side view?

 

[deemoss]

You could get it 3d printed in SS, might be the cheapest option depending on the required accuracy.

Accuracy is not paramount here. I'll get some quotes for SS printing!

 

[deemoss]

Peter's comments brought me back to reality .. for a visual, tactile prototype, in my retirement shop (now) I'd fab it up from sections of tubing or pipe & flat strip, full butt-welds or silver solder, or just tack welds if sufficient for 'function' of testing the idea.

Unfortunately, I don't have a local fabricator that could make this. I have 3D-printed prototypes (PLA and ABS) but obviously, for testing, it has to be made from the final material (SS). I'll try SS printing as per @Seesecurity suggestion.

 

[MCritchley]

Accuracy is not paramount here. I'll get some quotes for SS printing!

Let us know how much the quote is, always good to have a reference when a process is suggested.

 

[deemoss]

Let us know how much the quote is, always good to have a reference when a process is suggested.

One of the known prototyping suppliers (who I cant recall) quoted me $700 for SS printing.

 

[memphisjed]

No shade tree Jimbos bait and weld shop- but 3d ss printing available. We live in a foreign world to me. For 700 you might want to look into starting a bait and braze shack.

 

[Strostkovy]

For just one part, wire EDM is an option, but it will not be cheap. Cheaper than a forming die though.

Wire EDM the forming die then?

 

[swarfless]

How are you guys who suggest using a press brake intending on forming the 180 degree bend in the top left of the side view?

Well I'd start with the big radius then the top left tight one, bottoming die for sure possibly with a sacrificial outboard strip to be parted off straight after the bend, another awkward op for sure .. cut-off disc on an angle grinder. Then the top right bend, lastly the bottom right. Use same goose-neck punch for all the small radii. Sure it's awkward, it's a prototype, not meant to be easy. Production .. different story.

 

[MCritchley]

One of the known prototyping suppliers (who I cant recall) quoted me $700 for SS printing.

That seems reasonable.

 

[Orange Vise]

One of the known prototyping suppliers (who I cant recall) quoted me $700 for SS printing.

How much for two?

I think 3D printing is your best bet. Only having one prototype gives me anxiety though. A spare puts me at ease.

$700 isn't horrible but maybe they can do $1000 for two. There's virtually no labor component to this job.