Hey everyone, please help me figure this out.
If I want to build a top for my workbench that is 4 inches thick, 8 feet long, and 2 feet wide how many board feet do I need? Please provide the calculation that you used.
I cannot seem to get my mind around this.
Thanks in advance.
Bob
Replies
63 board feet. Think of it like a volume calculation. 12x12x1 is 144 cubic inches... 96" x 24" x 1" is 2,256 and times 4 (4" thick) is 9,024... which you can divide by 144 to get 62.6... or 63 board feet.
4" thick is pretty thick, I think my bench top (hard maple and padauk) is 2" thick with 16/4 end caps and a 4" border around the perimeter.
Thanks for the input. I am thinking of building the workbench featured in the book "Workbench" written by Christopher Scwartz and it calls for a 4 inch thick top. The guy at our wood supplier was suggesting ASH as it is relatively cheap, Oak for the same reason, or Maple which is quite a bit more expensive. Here are the prices for 6/4 stock.
Ash - 4.27 a board foot
Maple - 7.42 a board foot
Red Oak - 4.89 a board foot
White Oak - 5.99 a board foot
Any thoughts on which you would choose or even alternatives for obtaining the wood such as the internet or other sources? FYI, I live in the northwest suburbs of Chicago.
Bob, ash is an excellent choice. In fact, if you haven't already seen it, check out this ash Roubo bench from Schwarz's blog:http://www.woodworking-magazine.com/blog/The+Deluxe+Roubo.aspxNorman
Norm thanks for the link. That is impressive. It is something to aspire to.
Bob
64 bf is what I get for the finished top, but you'll need to buy extra to get that finished dimension to allow for shakes, knots, end splits and what goes up the dust extraction system while you get the planks flat and true prior to gluing up. For square edged rough sawn maple I generally add 50%, so you'd need to buy 96 bf-- call it 100 bf.
The yield from rough sawn white oak is even less generous in my experience; add 75% to that 64 bf, ie, buy 112 bf. Slainte.Richard Jones Furniture
Richard,
Don't they grade timber anymore in the States? I am thinking that if he went for example Red Oak he would most likely be better off buying a better grade such as comsels or clear one side stuff so there would be a much smaller wastage factor.
Philip Marcou
Sure they do philip. You're possibly trying pull my leg a bit. I like to buy sufficient to ensure there's enough for the job. From my experience of living and working in the US I found it prudent to allow about 50% waste in hard maple even if I purcahsed FAS and F1F grades: those are higher grades than the comsel grades you mentioned.
It meant that I fairly often had a bit of material to put into stock, but even that generous wastage sometimes cut the material requirements fine. I guess I'm fussy when it comes to selection of show wood, ha, ha. I grant a work bench top may not need to be quite so fussily selected as some table tops. Slainte.Richard Jones Furniture
Wot, me, pull legs??
But your figures for wastage allowance even on better grades inclusive of a small squirrel factor are interesting to compare.
In the eighties I worked in a factory in Darkening Africa making high quality furniture mainly for export, using American Red Oak. We used either prime grade or fair one side-other factories used comsels. The wastage factor was calculated at 20 percent and the subject of much discussion . The auditors (Price WaterMouse) thought it "reasonable", from one year to the next, but the Chiefs would want want to go either way depending on what the accounts were saying (in other words using stock valuation to manipulate things).Since I was initially the production manager and later the factory manager I was in between and it was quite amusing.
Actually I thought 20 % was generous on prime oak and border line on the next lower grade. Comsels were unsuitable for us as knots were not wanted. But then again there was no question of snipe so we weren't throwing away too much there (;).
Philip Marcou
philip, my snipe is not to be sniped at.
That's red rag to a bull stuff, but I'm not rising to your bait. And, actually, it's not been too bad lately, but that's probably because the machines have recently been serviced, and there haven't been too many clueless and clumsy hacks giving them laldy. Slainte.Richard Jones Furniture
Yup , the lumber is sold by grades and it's true the better the grade as a rule the waste factor lowers .
Besides the hardwood assoc. grading specs private companies create grades all their own . Select for color , width , grain .
Commons , select & better , fas lowest to highest are mostly what you find in Red Oak .
Typically with Northern ( there is a difference in Regions the true northern that of say Conneticut and North ) RO FAS my waste for stile and rail cabinet work is low maybe 10 - 15 % if that , it is very consistent , Soft Maple 35 - 40 % and higher , I'm on a Cherry job as we speak sort of , the waste looks worse then RO so far . 7 $ a foot , I'm looking on the floor a hundred dollar bill .
Can't imagine Richard thinking you a kidder imagine that
d
Edited 9/24/2008 7:45 pm ET by oldusty
you won't regret a 4" top, and considering you will probably have a bench like this for a lifetime + some more, you might as well go big!PS- I second the comment that ash is a wonderful wood. I really like working with it when I get the chance.
Edited 9/22/2008 6:50 pm ET by Woodman41
If you want the bench to look very nice, a hardwood like ash or maple (or oak) is a good choice. Another option is to buy fairly wide dimensional lumber like yellow pine (2 X10s) and rip 2 x 4s from the best parts for the bench. They'll be a fair amount of waste, but probably cheaper over all. Internet lumber sources generally don't make sense unless you are far from a decent lumberyard or are looking for an exotic (you can't pick your boards and shipping is expensive). Fir is another option. A lot depends upon pricing in your area. Soft maple is pretty reasonable here in SE PA, so that's what I'd probably use. It's dense, hard and fine grained. YMMV.Glaucon
If you don't think too good, then don't think too much...
FYI, I live in the northwest suburbs of Chicago.Go to Owl hardwood in DesPlains.. You can look all day and nobody will bother bother you! Ask and you may have to stand in line! Great folks there~http://www.owlhardwood.com/The selection of wood is something.. Most 'sticks' marked with the price!I live in Shiller Park...
Edited 9/24/2008 2:20 pm by WillGeorge
Will, funny you should say that, I went there two days ago. I grew up in Arlington Heights. That is where I got my prices for the hardwoods. I think I am going to go with the cheaper wood for now as another poster suggested.
Thanks for the post.
Bob
Did you mention that you were going to use hemlock framing lumber for the benchtop? If you do you'll find out why the stuff isn't really a good choice for furniture of finished projects. It warps and twists; it's only dried to framing lumber standards, and will shrink dramatically and unpredictably from where it is originally. You'll wind up with a very unflat benchtop, a lot of work wasted and money down the drain. In addition, hemlock is pretty soft. You can dent it with a fingernail.
Heck, you'd actually be better off laminating two layers of 3/4 inch Baltic birch plywood together and putting that on a nice framework. Or, as I mentioned before, laminating the plywood to a solid core door. Again, the birch plywood is flat and stable, and you can flip it over for additional wear surfaces.
Zolton If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Just when I thought I had the answer you gotta throw that at me.
OK, I got an idea of how much wood I will need but what truly is the most inexpensive but durable wood to use an a workbench that will give me the best results?
Bob
Chris Swartz wrote a book called Workbenches and makes a strong argument about making a bench out of Southern Yellow Pine from your local big box store. He claims that the wood is just as durable as beech. If you find yourself a copy of the book, it's worth the read.
http://www.lostartpress.com/product/3513e08a-2f07-4616-8f2f-74017f296377.aspx
Edited 9/25/2008 4:47 pm ET by mvflaim
If I wuz makin' a new bench, SYP would be my choice.
But I probably wouldn't get it at any orange & white or blue & white store. I've got a real lumber yard nearby that's great, and I find it MUCH easier to get straight stock there for not much (if any) more money. Heck, what I save on less waste more than makes up for any price differential.
The boxes have their uses -- and I use them a lot for certain items -- but straight, dry lumber ain't one of 'em. At least not in my neck 'o the woods.
Mike HennessyPittsburgh, PA
I'll have to agree with you 100% on that point Mike. Alway better to get your lumber from a local lumber yard rather than Lowes or Home Depot if you have opportunity.
Chris's rationale for SYP is that it is inexpensive and readily available in his area. Here in New England it's not. I corresponded with Chris and our own John White on this, and John suggested Douglas fir as an alternative in this part of the country, a suggestion Chris seconded. The bottom line is to find out what's currently used as floor joist material in your area, use that for your workbench, and be done with it.Norman
My thoughts exactly. There are a number of good candidate woods for a bench- SYP, Doug fir, beech, maple, etc. The would should be fairly dense and hard (as in ding proof, not necessarily hardwood). What you choose depends on cost, availability and your desire for aesthetics. The optimal wood will be different in Georgia than in Vermont.Glaucon
If you don't think too good, then don't think too much...
"find out what's currently used as floor joist material in your area, use that for your workbench"
Well, around here, that would be wood from the seldom seen, but often harvested, "Sprucepinefir" tree. While that is what I made my bench from (2X4's on edge), it did shrink -- a LOT -- over the first few years. I accounted for that in advance by holding the top together with a length of allthread every 18" through the top. As it shrank, I tightened up the allthread. Note that my bench does not have an integral end vice -- that wouldn't have worked well with this unstable wood. (Not to mention that it would be useless, since my bench is against the walls in a corner -- I hate small shops!) Don't know what the OP plans on doing in that regard.
Using construction lumber is fine, IF you allow for its foibles.
Mike HennessyPittsburgh, PA
Yes, moisture is the trade-off for an affordability when it comes to using a lot of construction lumber for a bench. Its MC should be checked and planned around.NormanEdit: I should add, in the interest of full disclosure, that my own benchtop is made from two sheets of 3/4" AC plywood. It gets the job done.
Edited 9/26/2008 1:21 pm ET by nboucher
"my own benchtop is made from two sheets of 3/4" AC plywood"
Not a thing in the world wrong with that -- totally avoids MC issues. ;-)
I am always a bit puzzled by folks who make their benches out of cabinet-grade hardwoods, polish the surfaces flat within .000000001" over the lenght of the bench, french polish to a lusterous shine, etc. Heck, I just couldn't bring myself to pound, saw, plane, paint and chisel on such a piece. I'd be too worried I'd mar the surface and thereby be condemned forever to WW-er's Hell! ;-)
Mike HennessyPittsburgh, PA
I have it already and the french bench is what I am looking to build. We do not have southern yellow pine by me (I am in northwest suburb of chicago) that is why i was think of using 2x12 hemlock. Any other wood suggestions?
Bob
Hemlock should work fine. Douglas fir will work well as well. Whatever your local lumberyard carries for construction grade material. Just make sure it's #1 premium grade so you get straight grain material that won't have as many knots.
I'm in the same boat as Mike Hennessy when it comes to building a workbench. A workbench is meant to be pounded, shook, clamped and spilled finish on. It's not a piece of furniture that you dust and spray Pledge on every month. Why spend $700 on some fancy wood when three months after you build it you accidently slipped your chisel and mar the top of your bench? Just buy whatever local construction grade building material you have available in your area for $200 and use the $500 savings to buy a new tool.
I'll be making a new bench this fall out of pressure treated wood for the added weight. I'm going to buy the wood and let it dry and acclimate for a few weeks before I start cutting it. If I develop any skin rashes in the process I'll let the Knots community know but since I use to work for a pressure treated lumber manufacturer and was around the stuff for years, I doubt that will happen.
Mike
Edited 9/29/2008 11:58 am ET by mvflaim
(I am in northwest suburb of chicago)
Go to OWL Hardwoods in DesPlains,, Bring alot of money.. You will find something!
Been down that road, i think i am going to stick with construction grade lumber for my bench. Don't have a lot of money right now to spend on a bench. (my main job is in the mortgage business), and things are a little (understatement) challenging right now.
I appreciate the idea though. I love going to Owl, they have a lot of great stuff.
Bob
i think i am going to stick with construction grade lumber for my bench.
My current bench is as such.. I sold all my old good stuff to put the girls (three) through college and had to mortgage my home! And rob a bank! Not really a bank,, Just my retirement funds!
Kenny,
If you haven't bought the material yet here is a link to a great sawmill/lumber dealer that has prices about half of what you are quoting for ash and maple and significantly less on the others.
http://www.kmhardwoods.com/index.htm
That will take you to their home page, a click on hardwood lumber products will get you to the page with the locations of their stores, about halfway down that page you click on hardwood lumber and it will take you to the page describing their inventory. About halfway down that page is a link to click on for their current price list. It is kind of hard to negotiate their site, that is why I gave you the step by step.
Their current price for hard maple is $3.11 b/f, soft maple is $2.81 b/f, ash is $2.40 b/f. All of those prices are for 6/4 select and better.
The nearest store for you is straight up I-94 in Caledonia, just north of Kenosha, right off the interstate. It is probably closer to you than it is to me, but I stopped there a couple of weeks ago and was impressed with the quality of the lumber and the service. Last week I went to their north store where they actually mill the lumber and I was blown away. I bought a bunch of soft maple for drawers and figured I could save money by picking through the #1 common (which they encourage, they leave you alone to pick out exactly the boards you want unless you ask for help), When I got it home and started planing it I found that fully half of it had very good curly figure. Too good for drawers, but I am not planning a trip up their again for a while so I will use it. How often do you get tight curl maple for $1.75 b/f?
As you can tell I am a very happy customer and I will give them my business from now on. While I was there the owner showed me a log they had just finished drying for a custom job. The owner brought in the tree and had them mill it for his private bar. It was 8- 3"x 28" x 16' natural edge slabs that had almost no visible sap wood and were beautiful. They also had a piece of Bubinga for sale that was over 3' wide and 20' long. Bring a trailer and a credit card!
Rob
Thanks Rob A. I will definetly check this out. It really is not much more of a drive than going to Des Plaines.
Bob
Woodman, your calculator may be broke 4*96*24=9,216
9216/144 = 64
So the board foot would 64 board feet for the top + another 30-40% for waste.
Bob
you used a calculator?
Yea I did, the path of least resistance and I am work so its right on my desk :).
Thanks for all the input.
Bob
I have seen some becnh tops made of glue lams
Here's a simple way to think about this calculation. Figure out how many square feet the surface of your finished top will be -- in your case, 8' X 2' = 16'. Then multiply that by the thickness, in inches -- in your case 4, so 4 X 16 = 64bf. (Each square foot of surface area is 1 bf if it's 1" thick, 2 bf if it's 2' thick, etc.)
For a bench top, I don't think you'll have to allow a whole lot for waste, since I presume that you'll be laminating the stock such that only one edge is showing. Your main source of waste will be end cutoffs. You'll need to buy 9'+ to be able to trim splits & snipe off the ends. But that's pretty much all the waste you'll need to allow for unless you get some pretty poor grade wood. FAS-graded lumber should be fine. You may even be able to get by with #2. Hey, its a workbench, not a highboy!
Mike Hennessy
Pittsburgh, PA
Edit: As for type of wood, I built my first workbench some 35 years ago out of 2 X 4s on edge, 'cause that's all I could afford then. Figured I'd build a better one some day. I'm still planning on doing that, but so far, my first pine bench has been all I need. ;-)
Edited 9/24/2008 7:09 am ET by MikeHennessy
I don't know about you all, but I've got better things to do with my shop money than to sink it into expensive lumber for a bench top. For the past five years I've been working on a simple bench made of a solid core exterior door (5 bucks from a local lumberyard - it had been mis-drilled by a customer, and had some chips along the edges), with a sheet of 1/2 inch Baltic birch screwed to that. It's been the flattest and most durable top I could hope for - much more so than my previous bench top, which I built of solid maple.
When the top wears out or gets too beaten up to deal with, I'll either flip the top sheet of birch or simply get another piece for 40 bucks or so. But, at the rate I'm going, and because I work on and not into the top, it could be a decade or more before that eventuality occurs.
Of course I understand the desire to make something beautiful for oneself, like a killer bench. And it can also serve as an example of your work if you show it to clients. But at the lumber prices you quoted, you're going to have a ton of money invested in this thing, and at the end of the day it's just another tool. I'd go simple and inexpensive and invest your money in other things - like a good router or slot mortiser - that will make your life easier and more productive down the road. A good, flat, durable bench will do the same. But other than the aesthetics it doesn't matter what the top is made of.
Zolton If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Awesome advice. And I agree with all that you said. After adding up the price of ash, oak or maple using less expensive wood is the way to go for me.
Bob
I now am thinking of buying some 2x12's that are 10 feet long that are made of hemlock. My brother is in the lumber business and says I can get them for under 10 bucks. According to my calculation I will need at least 11 of them. And hemlock seems to be a better choice than pine right now.
Since it is a "workbench" using inexpensive lumber makes complete sense to me.
Your input was very helpful.
Bob
Bob ,
Before you buy wood at least go to the local lumber yards and check to see if they have a remnant piece of a glue lam beam ,if not price one out it may surprise you, many are 3 1/2" , the cost and labor factor are less and they have already been surfaced , and here out west they are typically Fir which imo is much harder then Hemlock er Hemfir.
dusty
I will. It makes sense to do.
And don't forget to look for bowling alley salvaged wood.
Everybody is talking "net" b/f, not gross. "How much wood do you need?" is a different question from what is the net wood in the top.
To buy the lumber, here is how I figure it:
8/4 material (assumption) will dress to 1-3/4". 24" width will require 14 pcs (at 1.7143 thick). Eight foot lumber won't work due to end checks and rough cuts, so you may need to buy 10' long (or longer!). So that is 14 pcs 5" or wider, x 10' long, or 116.666 b/f. The width is a wild card. If you get a bunch of 8"-9" wide boards, the b/f to buy will go up. Or you can glue the off cuts together to get the 5" blanks to keep things a bit more predictable.
120 b/f is a lot different from 63 (?) or 64'.
Dave S
http://www.acornwoodworks.com
"Everybody is talking "net" b/f, not gross."
Hmm? I certainly didn't. I thought I'd made it pretty clear in my post there is a wastage factor and an allowance must be made.
Perhaps you didn't read it, or if you did what I said didn't register. Slainte.Richard Jones Furniture
Right you are, I missed it. Considering the nature of the original question, most of the answers would lead to the next round of questions - "How much waste?" "How can I know?" etc. As you know, the only succinct answer to those questions is "it depends." This is the hardest thing to know when buying for a specific use when you don't control the supply. It has taken me years to feel like I know what I'm doing, yet I am still regularly humbled and retrained. I like to buy twice as much, and use the (hoped for) leftover for smaller projects, but it sure is piling up around here.... Dave S
If you want a beautiful bench top...
Get a slab of Purpleheart!
Expensive and impossible to work with most hand tools!
I'm a nut and use it all the time!
EDIT: Somebody posted ASH! A very nice wood (hickory also) to use..
Hell, pine with a 1/4 inch of tempered hard board on top works!
Or MDF!
I'd say a work bench is ... YOU ... and how you work .... or want to show it off. NOTHING WRONG with the show piece! I made one all of purpleheart and sold it for about what I paid for the wood!
I was young then and needed money for the NEW child! Actually, I forgot why I sold it!
Edited 9/24/2008 1:08 pm by WillGeorge
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