Quantifying the Waste Factor

How much of the lumber you buy becomes scrap instead of cabinets? Shop owners report their observations. December 27, 2007

Question
I'm currently doing some cherry t&m cabinetry. I haven't used cherry in about 5 years. I had forgotten how much waste factor the sapwood takes up. Our products cannot have any sapwood, unless it is absolutely covered and not visible. What percentage of waste factor do you estimate for cherry cabinetry and millwork? Any other woods that are this tough? I find I spend a lot of time sorting and cutting to fill a cutlist.

Forum Responses
(Cabinetmaking Forum)
From contributor S:
If I'm really selective in the lumberyard, I'd say about 10% waste due to sapwood. But if I just take it as it comes, probably 25-30%. I make it a practice to never go in for wood if they are low on supply; all you get is what's left over from guys like me. The other woods I've seen as a problem are maple - where we don't want heartwood - and hickory. I've had some clients who don't want much hickory heartwood.



From contributor D:
Picking and choosing is okay if you're only getting a few bd. ft. (100 or less), but nobody's going to let you sort through if you're getting 1000'. Since sapwood in cherry is not considered a defect, it all depends on the stack, unless your supplier sells premium cherry. Then it's only about 25% sap and about 25-35% more expensive. The best thing to do is learn to color sapwood.


From contributor A:
The way they seem to grade it is as long as one side of the board is heartwood, it counts as select. Unfortunately, 75% of the board can be sap and still have one good face. I still think you guys are way too low on the waste factor.


From contributor B:
Depends on how you do the math. If you need 100' of finished product and have a 30% waste factor, you would need to purchase 143' of material. Your waste factor would depend on your product dimensions, the raw material dimensions you purchased, and so on. Smaller parts usually have a lower waste factor than larger parts. For cherry, I use a 50% factor. Sometimes it runs a little less, but better pay for it than not. I am picky about grain, so cherry has a higher waste factor than, say, a painted product.


From contributor W:
In general, I think waste is grossly underestimated, by your numbers here and from everyone else I have talked to. I buy lumber by the truckload, and the quality on several species is many times better than you can get at the local supplier. We make doors, use Tigerstop optimizers, SLR our own lumber, use all the cutoffs we can, etc. After running all the numbers comparing purchased lumber to square feet of doors sold, here is what I get:

R.O. - 1.85 bd ft of lumber to make 1 ft of door. Northern red oak, wide, mostly clear, no sap.
Maple, hickory - 2.18 ft northern.
W.O. - 2.50 usually no sap, #1 comes from the center of log, all heart.
Cherry = 2.22 usually no sap. #1 comes from the center of the log, so it is all heart. Local suppliers sell #1 that is almost all sap.
Ash - 1.63.
Walnut - 4.5 to 5. Some loads have very little sap, but some have 15% of unusable boards due to sap.



From contributor U:
It depends a lot on the grade. Because I am pressed for time on most orders, I tend to order A grade cherry (90% heart face) and end up ordering 30-40% extra. Because I have several suppliers competing for my business, I can ask about their stock availability when I order. They know by now that I will return stock that doesn't match what I told them I want, and have another supplier deliver more the next day. I reward good suppliers with repeat orders even if their price is higher.

I've tried dropping down to #1C to get better prices and ran into lots of issues with color, not just knot type defects. Not such a big deal for stain, but creates a mountain of waste for clear finishes - more like what contributor W is documenting.

I try to meet the wood salespeople personally to explain the criteria for getting my business. Some organizations get it and deliver, some have no communication with the pickers in the warehouse and never see another order.