How to prepare SYP to make a bench top?

[dan sherman]

I finally finished a bunch of projects, and I’m now ready to start working on my benches. I have never done a project like this before, and thus have a bunch of questions; hopefully some of your more experienced guys can help me out.


I got a moisture meter for Christmas and thus my first question; how dry should the SYP be before I start working with it?


I plan on making the bench top 4” thick and 6’ long. I was planning to buy 14 foot 2x10’s and quartering them, thus yielding 4-½” x 7’ rough cut stock. Is the + ½” width and + 1’ length enough, or should I go larger?


In regards to 1 & 2 what’s the best way to prepare the rough stock? I know I need to let it dry out, and acclimatize to my shop. Do I rough cut it and then stack it to acclimatize and dry, or the other way around?

[Eric Sayre]

Dan,

I just went through this a few days ago to make a couple of benches. The lumber had been stacked in my shop for about 2 months.

You should be fine on the length.

I used 2x8 lumber, ripping it once down the middle, then removing the "rounded" edges. I ended up with about 3 1/4" widths. After completing the glue-ups, I ran them through the planer. The bench seats measured a perfect 3" thick after cleaning them up.

The 2x8 SYP that I used was a perfect 7 1/4" width as it should be. Based on that, as long as your 2x10's measure 9 1/4" you should end up with 4".

I was a little bit generous when I took the edges off, as well. This could have been done in the planer after the glue-up, and possibly yielded a thicker bench. Just remember that when you are working with Southern Yellow Pine - ANYTHING could happen. When you rip it, it will take it's own shape. Be patient and be careful.

Good luck!
Eric

[Travis Teichmann]

Dan,
1. I would let the lumber acclimate for a couple of weeks without any ripping. If you need to cut them to 7' to store them, I don't see that giving you any troubles later.

2. If you're concerned about not having enough width after ripping the 2x10, only rip the rounded edge off portion of 2x that will be seen on the top of your bench. Once you have it glued up you can then flatten the top in a planer. If you still have enough material you can then plane off the bottom side until all the rounded edges are gone, or not. 99% of the people that come into your shop will never look at the bottom side of the top.

I'm in the process of making a bench as well, and I'm using 3 sheets of 3/4" ply (generously donated by a friend replacing his benchtops) with 3" oak on top with oak banding to full thickness all around. The top will look nice and be incredibly durable, and it adds thickness and weight. I don't really care what the bottom side looks like. Hope this helps your decision.
Travis

[Pat Germain]

Wiping the glue surfaces down with acetone helps improve glue up, according to Chris Schwarz. I did this when glueing up the douglas fir base for my workbench and it did indeed remove some of the pitch on the glue surface.

[Jamie Buxton]

The "how dry" question depends a little on what you expect to do. Cabinetmeakers generally expect lumber to be dried to something around 9%. That's the level it will eventually reach. If you use lumber which is wetter than that, it will shrink as it dries, and it may warp too.

Construction lumber, which is what I'm guessing your SYP is, is often sold green -- completely undried. If it is kiln-dried, the industry standard is 19%. If you have enormous patience, you can air dry your stock and then build the bench. Be prepared to wait a year or more.

The other approach is to build the bench with the lumber in whatever state it is currently in. You get to use the bench immediately, which is good. However, you should design the bench so that if the top shrinks a bit across the grain there won't be problems. And you should be prepared to re-flatten the bench as it dries and moves.

[David Keller NC]

SYP will actually dry quite a bit faster than cabinet hardwoods like oak (and especially) walnut and maple. Stacking and stickering your lumber will be well worth your time, even if it only sits in the stack for a couple of weeks. It will not have reached its equilibrium moisture in that time, but it will have lost a lot of weight (which is good - it's heavy stuff when green).

If you want this to go faster, rip the wood for the top on your table saw before you stack and sticker it. The extra exposed surface area will make the drying go more quickly.

For this purpose, I'd ignore the moisture meter. Unless you want to wait months for the wood to reach equilibrium, it's not germane to the project. And a workbench is not a piece of furniture - it doesn't matter if it warps a little, so long as it's flattened after it does.

[dan sherman]

If it is kiln-dried, the industry standard is 19%. If you have enormous patience, you can air dry your stock and then build the bench. Be prepared to wait a year or more.

The wood I'm looking at is at my local Menards, and is listed as #1 SYP. It doesn't actually say if it's kiln dried or not, I still need to check that. It looks dried to me (though I'm a newbie and could be completely off base).



If you want this to go faster, rip the wood for the top on your table saw before you stack and sticker it. The extra exposed surface area will make the drying go more quickly.

For this purpose, I'd ignore the moisture meter. Unless you want to wait months for the wood to reach equilibrium, it's not germane to the project. And a workbench is not a piece of furniture - it doesn't matter if it warps a little, so long as it's flattened after it does.

I'm not really interested in reaching equilibrium, I just want it to be dry enough to avoid glue joint failure.

[David Keller NC]

"I'm not really interested in reaching equilibrium, I just want it to be dry enough to avoid glue joint failure."

There's no possibility of glue-joint failure. You've a tremendous surface area for glue on the laminates for the top. Even a weakly clamped joint will be impossible to take apart once the glue sets.

[Dave Lehnert]

SYP will not stay as dry as a hardwood will. I made a small bench out of SYP and I just let it dry for a week in the garage. Have not had any problems with it at all. At the Lowe's here in town the 12" stock was much clearer (less knots) and flat (No twists) than the smaller size. Check your store out to see if the same holds true.

If you have not purchased it all ready the workbench book by Christopher Schwarz is the bible. After reading the book I came up with a totally different disigine that I started with. A must read. He talkes a great deal about the use of SYP for a bench.

http://www.amazon.com/Workbenches-Design-Construction-Popular-Woodworking/dp/1558708405/ref=sr_1_3?ie=UTF8&s=books&qid=1230930024&sr=1-3


http://ecx.images-amazon.com/images/I/21TcnfJSrdL._SL500_AA180_.jpg

[dan sherman]

I stopped by Menards while I was out shopping today, and the SYP they have is kiln dried to 19% (stamped on each board). I did some research when I got home, and found that the average EMC in my area of the country varies from 12.5% in May to 15.7% in December. Since the bench is going to go in an unheated garage shop I have a feeling i won't have to let the wood dry that long to reach equilibrium.

[John Thompson]

My current 15 month old bench-top is SYP, Dan. The last five I have built have had SYP tops and Doug fir bases. I just flattened mine after 14 months of heavy use and it was off more than around ..030 in one small area. It is stable once face glued.

I would not make the top 4". I prefer 3" as that is plenty as plenty thich for stability and not too thick for clamping. When you face glue 3" wide studs it isn't coming loose. Just have plenty of clamps and cauls.

I purchase 2 x 12's and if you want the table 7' long I would purchase the 8' lengths. But.. the reason I buy 2 x 12" is I intentionally only going to yield two studs from each 2 x 12. I try to pick them dry and with the pith as close to center as possible.. and be sure they are straight on the rack. If not straight then.. they probably won't be after acclimation.

I bring them home and rip the 1/8" round-over off both edges.. then sticker them to get down to around 14%. That is too high for furniture but fine for a bench-top with that much face gllue. At that point I rip 3" off the outside to get one stud. Then turn it around and take 3" off the other side. The center section with the pith is then thrown in a utility box for latter use. The pith is not stable and by doing it this way.... you have in essence quarter sawn stock left as your growth rings will look like this which is quarter-sawn with some rift sawn. /////////

Opps.. accidentally posted so I will use second post to finish.

[John Thompson]

Then sticker again for several days to acclimate in shop after the new wood has been exposed. At that point ready to glue doing 3 studs at one time. Once I get two sets of three.. I glue them together and add 3 more until done with the entire width.

Hope that might help... some pics of what I had to take off to re-flatten after 14 months. Done in about 6 minutes with a #7 jointer. First is after flattening and second is a light over-all sanding. Just click on the show-threads to view the pictures at the bottom.

http://www.sawmillcreek.org/showpost.php?p=992331&postcount=1

http://www.sawmillcreek.org/showpost.php?p=992455&postcount=6

Sarge..

[Paul Coffin]

How does SYP compare to Douglas Fir? Up here in the Northwest, the only inexpensive softwood I see in the big box stores is Douglas Fir that is usually from young trees with lots of knots. Good clear quartersawn Douglas fir costs more than than a lot of hardwoods. We do not seem to get SYp up here.

Paul

[dan sherman]

How does SYP compare to Douglas Fir?

see the following pages:
http://books.google.com/books?id=Ihc9Ma0i6rQC&pg=PA15&vq=stiffness&dq=Workbenches:+From+Design+And+Theory+To+Construc tion+And+Use&client=firefox-a&source=gbs_search_s&cad=0


page 15 : stiffness chart
page 16 : weight chart
page 17 : hardness (Janka Scale) chart

[John Thompson]

How does SYP compare to Douglas Fir? Up here in the Northwest, the only inexpensive softwood I see in the big box stores is Douglas Fir that is usually from young trees with lots of knots. Good clear quartersawn Douglas fir costs more than than a lot of hardwoods. We do not seem to get SYp up here.

Paul

Dan has posted a chart but I can tell you it is lighter.. more apt to spliner on the edges when throughly dry but that is not a problem if you know.. and it is extremely stable. The current Douglar fir is not as good as the Doug Fir of years past as they harvest early. I took several 10" x 12" x 30' beams from a warehouse here in Atlanta that was being torn down to build the Georgia Dome.

Those were in civil war era warehouses around the railroad yards and they were as straight as the day they were put up as ceiling beams. Pretty hard also once dry just as SYP. But... I prefer the SYP on top as it is easy to work.. cheap here (my top cost $22) and it's also stable. Houses here use them for framing studs. I have seen some studs that get so hard you have to drill a pilot hole to get a nail started after it case hardens on the outside.

Hope that helps...

Sarge..