Cost Analysis Spreadsheet - I need your data!

[JavaLodge]

Well, being an engineer, I'm constantly thinking of ways to analyze my progress and predict costs. I've come up with a pretty bare boned spreadsheet that will estimate your costs for fiberglass, resin, and body filler based on the surface area of your project.

https://dl.dropboxusercontent.com/u/8972312/The%20Books.xls

The only problem is the analysis is based on only one point of data, my quick experimentation with a test piece. It's likely that I used too much or too little of any material. If anyone would like to donate their data, I can average it into the spreadsheet to provide a more accurate analysis. I really hope this is helpful to someone, and if you have something to add, go right ahead! If you feel you've made a significant addition, just repost the file here.

-Java

 

[Jason 078]

And I thought I was OCD...

That is more thought that I actually give. Though, I have another form of estimation.

I buy more than is necessary, use what I need, then refine the process with the following project. As of right now, I have it down to approximately the following amounts:

Hardening (2 layers on each side): 1/8 bottle of Smooth Cast 300 Trial Size per page (4 oz per page)
Sanding detail (poured like rondo): 1/64 bottle of Smooth Cast 65D per page (approximately 0.5 oz per page)
Fiberglass (cloth cut into squares): 1/3 sqft of fiberglass cloth per page (double layer in different alignments)

The fiberglass is put into the piece with spray adhesive and uses Smooth Cast 300 as the resin agent. It is then covered with a light layer of the Smooth Cast 65D to seal the edges.

I guestimated the original estimates, which is all anyone can do. After each project, I enter the new numbers in to refine it. You can't say specifically how much is used per square inch/foot, because you will always have problem areas (small details, pieces that need particular fills, etc.) that will require more or less material.

Basically, I'm saying that you should keep the data rather loose in its conclusion and results (with more give than take). Otherwise, you might find yourself with too little material for too much parts.