Fair market value for scrap

[geomapguy]

Originally Posted by Bob Steele

That's not exactly correct. In your Bill of Materials you need to include the cost of the metal you had to purchase in order to make the part. If it required a 4 foot X 2 foot piece of aluminum to cut out your part you must include the cost of the entire piece. You don't have to purchase it that way but you do have to find out what the smallest piece that you could purchase is that you could have cut your pieces out of and use that as a cost in the BOM. You can't just figure out the square feet of aluminum in your parts and multiply that by some square foot cost and put that in the BOM. The waste counts.

Yes this is correct

Example from manual

Example 6: A Team purchases a 4 by 4 ft sheet of aluminum, but only uses a piece 10 by 10 in. on their ROBOT. The Team identifies a source that sells aluminum sheet in 1 by 1 ft pieces. The Team may cost their part on the basis of a 1 by 1 ft piece, even though they cut the piece from a larger bulk purchase. They do not have to account for the entire 4 by 4 ft bulk purchase item.

[pfreivald]

But still, finding a general price from onlinemetals or metalsupermarket and prorating it is the right way to go--you don't have to account for an entire 4x8 sheet if you used a 1x1 square of it. Just prorate for the waste you make, too!

[MechEng83]

Originally Posted by pfreivald

But still, finding a general price from onlinemetals or metalsupermarket and prorating it is the right way to go--you don't have to account for an entire 4x8 sheet if you used a 1x1 square of it. Just prorate for the waste you make, too!

Our local metal vendors will sell cuts of extrusion and sheet at a pro-rated price, generally by the foot. For example, if I wanted a 1' piece off a 25' extrusion that costs $50, I'd pay 2 bucks and walk out of there.

[pfreivald]

Originally Posted by MechEng83

Our local metal vendors will sell cuts of extrusion and sheet at a pro-rated price, generally by the foot. For example, if I wanted a 1' piece off a 25' extrusion that costs $50, I'd pay 2 bucks and walk out of there.

We get our sheet aluminum for free from an awesome local sponsor (a small machine shop), so have the great burden of having to figure out what we'd have paid for it had we paid for it.

[FrankJ]

Teach me not to go by old rules. This one is kinda unworkable though. But in this case, since the shop would otherwise sale it for scrap by the pound, that is the fair market price.


Example of unexpected applications of this rule: So 3D printers that use expensive cartridges have to cost parts at the price of the cartridge since that is smallest unit price?

[Al Skierkiewicz]

Frank,
That opens a real issue, teams should cost as if they were purchasing the smallest quantity as shown in the copied rules. Your sponsor's scrap may be my sponsor's bread and butter.

[FrankJ]

I see your point Al. I have to admit that since our robot has never come close the budget limit, we have been conservative in costing stock, so I have not thought much about this rule. The trouble about pricing metal is that on an industrial scale the price depends on a lot of factors. So figuring out a true price for the minimum quantity allowed in the rules is always going to be a little arbitrary.

In our case we buy stock in bulk. Much gets used for stuff other than the comp bot. The price/lb is affected by the total buy, but I do have an idea of a minimum sell quantity of a particular shape so I guess that is what we will use.