How much increase in bdft of material beyond what the project calcs to?

[George Bokros]

How much extra do you buy for waste, ooop's and sawdust, 10%, 20% more less??

I do not have room to store much more excess stock.

Thanks

[Mike Henderson]

That's really difficult to answer because it depends on a lot of things. When I go to buy wood, I try to figure out how I will located the pieces I need on the wood I'm buying. Sometimes things don't lay out nicely and you have to buy a fair amount more than the board feet you calculated. Sometimes the wood is a lot wider than you need and the pieces you rip off can't be used on the project.

Other times, things work out exactly right.

Also, it depends on the mistakes you make and that's hard to calculate.

But as a rough guide I'd say 20%. The problem with buying too little is that when you go back, you can't find wood that really matches what you bought originally.

Mike

[Matt Day]

Higher the better. Depending on the size of the project and cost of wood i’ll Go as high as 50%. Better to over buy than take the time to go back for more.

[Larry Edgerton]

I figure estimates at 25%, always rough stock but then usually buy 50% more if I am low on that species. If the wood is inherently difficult I will bump it up accordingly.

[Cary Falk]

I shoot for 20%. Sometimes it is too much. Sometimes it is not enough.

[George Bokros]

That's really difficult to answer because it depends on a lot of things. When I go to buy wood, I try to figure out how I will located the pieces I need on the wood I'm buying. Sometimes things don't lay out nicely and you have to buy a fair amount more than the board feet you calculated. Sometimes the wood is a lot wider than you need and the pieces you rip off can't be used on the project.

Other times, things work out exactly right.

Also, it depends on the mistakes you make and that's hard to calculate.

But as a rough guide I'd say 20%. The problem with buying too little is that when you go back, you can't find wood that really matches what you bought originally.

Mike

I try to do this also but sometimes I loose my place in my laying out because i figure some this part and some of that part in single piece then try to figure out what you have already accounted for after doing this with several pieces.

[glenn bradley]

The eternal answer . . . it depends. Like Mike, I have a list of parts when I go looking through my stacks or through the yard. I check off the parts as I find them and even chalk them out on the boards before I ever get to the register. I may want a specific sort of figure for drawer fronts. This pattern may or may not be near the edge of a board, follow the mills rip lines and so forth. This means the blank for that drawer front may come out of an odd position in the board and at an angle. This results in more spoil but, I get the look I am after. Odd pieces of spoil can be used for small parts, secondary wood on another project or even a whole project if it is small enough. I can say without reservation that I would rather have 10bf left over than have to go back to the yard and try to find a matching 3bf for a project 90% done ;-)

[roger wiegand]

it really depends on the quality of the wood and the details of what you are trying to cut. I've lucked out and only used 5% over the total, other times 50% barely made it. I'd guess 20% is a reasonable average, but you really don't want to get caught one board short. If you are cutting a lot of small pieces you don't need to be over by as much-- Always cut your large pieces first. It also depends on how carefully you match grain and color and pay attention to which board goes where. The fussier you are the more extra you will need.

For very expensive wood or special figure I will plan cuts very carefully, perhaps changing the dimensions of the project to fit the board.

90% of what I do is made from cherry, maple, and walnut with poplar as a secondary wood, so I just keep a good stock of those on hand so I don't run out in the middle of something, or make a bad compromise "making do" with what I have on hand.

[Rod Sheridan]

Hi George, if you're accounting for sawdust, then start with 25% as that much normally winds up being removed by jointing and planning.

Another 10% for end trimming, maybe 10% for stock selection and another 10% for trimming.

That works out to 55% which seems about right looking at my records for various furniture pieces, however I've been at 100% or more when I really wanted nice grain matching...........Rod.

[Ted Derryberry]

If you're buying 4/4 and milling it to 3/4" you need 25% for the milling alone. However, who figures a project like that? I figure how many lineal feet of a certain width and thickness I'll need and go from there. I take my list and a calculator to the lumber yard and see what's available. Sometimes I want 10' material but have to buy 12'. That can be a 20% loss right there or I can sit down and refigure how to cut my parts out of 12s instead of 10s and reduce the waste. I'll usually buy 5% over on the quantity of boards just to allow for screw ups on my part. If I don't screw up I save it for the next job. Consider that I'm hand picking each board so there's usually no real surprises unless I completely miss something.

One variable that I didn't see mentioned above is the project itself. If there are a lot of "back sides" and other hidden areas where you can use up less than perfect material then your waste factor goes way down. Larger projects also tend to have less waste as there will be more total parts, including small parts which can eat up the offcuts and "bad" boards that you can't get a long piece out of.

[Lee Schierer]

I buy my lumber S4S from my supplier. I have a program I purchased years ago that allows me to enter lengths and widths of pieces. I can select the size of the raw material I want to use to make that part. The program will optimize the way to cut the pieces from lengths of stock. For initial calculations I use standard lengths (i.E. 6, 8', 10' etc.) and the program calculates the best way to cut the pieces and how many pieces are needed for each width of board. It allows for kerfs as well. Once I purchase the material, I measure the actual length of each board I bring home and enter those lengths as "stock" material. I can also include lengths of material left over from previous porjects and un the optimization again. This usually results in a significant amount of left over material from what I purchased. If I make no mistakes when cutting i normally have enough wood to make the project. Errors or design changes sometimes cause extra material to be purchased.

The program is called Sheet Layout, but it is no longer being sold. There are some trial versions that can be downloaded, but those versions have limits on the number of pieces you can enter. The licensed versions had larger part capabilities.

[Don Bullock]

Other than figuring out the cost of a particular board I don’t even consider board foot in creating projects. My projects are always based on the grain pattern in the wood. I try to maximize the visual affect and perhaps strength of the wood I’m using for each part of the projects I make. While this process may create more waste and therefore increase the cost I believe it is worth it.

[Brad Shipton]

It also depends if you get to pick it yourself or not. My stock comes on a truck and is picked in a warehouse by a picker. If you get to pick it, then 25% as Rod suggests can be fine, but in my case it can be more. If working with Cherry or Walnut it also goes up a lot more if you need to cut off the sapwood.

[Bill Adamsen]

I buy different hardwoods and from a variety of suppliers, typically local sawmills though some stocking resellers. It comes in many flavors from d4s to rough. I find few woods source consistently enough to provide a blanket statement. Roger's statement is pretty much my story. Occasionally project specific requirements such as one of the oaks. 25% is probably the best number for estimates.

[Brian Holcombe]

For projects I cut all the time, 10%. For new projects 25%.