Part cost estimation??? 1

[jaykm]

Hi all,
I have a plastic part for which I need to estimate approximate cost/part. I have a choice of 3-4 materials (PC,ABS,PC+ABS blend,Glass filled PP).

Could anyone point me to a source where I can get some means of estimating how much the part would cost for each of these materials?

Thanks,
Jaya

 

[MadMango]

Have you tried to send a RFQ (Request for Quote) to some of your vendors? They should be able to give you realistic quotes.

[green]"I think there is a world market for maybe five computers."[/green]
Thomas Watson, chairman of IBM, 1943.
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[jaykm]

Hi Thomas,
Right now we don't have any approved vendors and this is a New product in development. I was thinking of posting the part into Quickparts.com or other Rapid molding sources but I would need to get permissions from dept. heads to do that..hence I was wondering if there was some kind of hand calculation just to estimate the what kind of numbers we can expect.

Thanks!
Jaya

 

[jaykm]

Oops!
I missed it.. should have been addressed to MadMango!

Monday blues
Jaya

 

[MadMango]

You could try to compare the part to similar parts that you already have made. Pick a part that has the same material and manufacturing process. Take that price and calculate the volume of material against the price, and scale that up or down for the new part's volume.

Using a service like QuickParts won't give you a production part price, as they are only capable of low volume prototype production.

[green]"I think there is a world market for maybe five computers."[/green]
Thomas Watson, chairman of IBM, 1943.
Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[patprimmer]

Find a local moulder with a good reputation for integrity if possible and ask him to quote in all possible materials.

It is a lot more complicated than just material costs.

This should be done before the design is finalised as the material choice could effect the design.

For instance, say you are considering a part in nylon or PP.

PP is 25% the cost of nylon on a volume basis, but is not as strong, so some dimensions might need to be increased to get enough strength with the PP. This will change the volume of the part in PP vs nylon, and lose some if not all of the weight advantage of the PP.

PP moulds slower than nylon, this will also influence the cost, and in extreme circumstances, I have seen it more than completely negate the material cost advantage.

PP is more prone to warpage, but less prone to flash. PP will not flow as far in a mould as nylon. These characteristics may or may not impact on both design and cost, depending on the part. You need someone with real experience to assess the design and work out a quote.

Regards
pat pprimmer@acay.com.au
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