Working with Construction SYP

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Forum topic by HorizontalMike posted 09-03-2013 11:10 PM 2261 views 0 times favorited 27 replies Add to Favorites Watch
View HorizontalMike's profile


7898 posts in 3799 days

09-03-2013 11:10 PM

Topic tags/keywords: syp southern yellow pine cupping

Well, I thought I would cheap out in building a modified “6-Board Chest” and picked up a handful of 2×8 8ft SYP boards from Big Orange(HD). I figured that at ~40% the cost of picking 1×8s how could I lose, especially with all that extra to thickness that can be planed down to perfection, right?...

I resawed about 3/8in off the thickness and then jointed and planed things down to 1in. I let those set for 2-days before planing to final thickness of 3/4in and immediately butt-glued two board pairs up to get my desired 14in width.

I had left one board, the one I planned on making the legs/ends of the bench at 1in upon glue up. The next morning I started out by cutting everything to final size and dado’d and scroll sawed the appropriate parts. My chest end “leg” boards had a pronounced “S” look from the alternated crown glue up, so I took it to the jointer to flatten and then planed both legs down to 3/4in (had to trim to 13in width to fit my planer). Glad I had left this one with so much extra thickness, as it paid off here.

Mounting the 14in wide front and rear boards, which had already started to cup slightly, took some extra cut nails to make a good fit. The bottom of the chest had to be planed down to just 0.700in, and even then it took some major effort to fit it in the dados on the end boards, but I got’er done.

By the end of yesterday the chest carcass was built and I had just cut the top to fit (+ an 1/8in) and called it a day. Went back out today to hinge the lid and lock, but found a significant cupping. I did a crown-crown glue up so at least the cupping is somewhat even across the entire width. The image below shows the lid with 70lb of weights on it to attempt to straighten out the cupping until I decide what to do next.

The lid will have a 7/8×1in molding/border around the sides and front. I realize that I am going to need to install some internal ribs to try and straighten out the cupping. And that leads to the following…

If I soak/wet one side of the lid board (crown side), will that at least temporarily, swell the crown side enough to straighten the board out long enough that I can install three or four hardwood ribs to hold the board straight in the long run?

FWIW, I plan on milk painting both interior and exterior to hide the fact that my wide boards are glue ups and not single cut boards. I am hoping that by painting all sides, it might help stabilize any more wood movement once I get it into the house. I am sure that the 108F in the shop is not doing me any favors either.

Also, feel free to share any tricks/tips for working with SYP if you have found any that work…

-- HorizontalMike -- "Woodpeckers understand..."

27 replies so far

View madts's profile


1942 posts in 3224 days

#1 posted 09-03-2013 11:16 PM

Just lay the top in the grass in the morning, with the cupped side down, and watch it. It should only take about 15-20 min. and you will have a straight board.

-- Thor and Odin are still the greatest of Gods.

View Woodmaster1's profile


1553 posts in 3472 days

#2 posted 09-03-2013 11:50 PM

Great idea if it works. That is something I never would have thought of. I think it is great to get tips like these. Simple and easy to do.

View Don W's profile

Don W

19726 posts in 3452 days

#3 posted 09-03-2013 11:54 PM

I’ve had madts process work, and I’ve had t not work. You won’t know if you don’t try. It won’t make it worse.

-- - Collecting is an investment in the past, and the future.

View TheDane's profile


5868 posts in 4548 days

#4 posted 09-03-2013 11:56 PM

I have found that SYP is best when I cut it into 16” to 18” long pieces and throw it in the fire pit.

-- Gerry -- "I don't plan to ever really grow up ... I'm just going to learn how to act in public!"

View HorizontalMike's profile


7898 posts in 3799 days

#5 posted 09-04-2013 12:03 AM

My only problem is that I have no mowed grass. I sold the lawn mower 12yr ago when we moved out in the South Texas Hill Country. It sounds like I might get by using a damp towel on the concrete shop floor and letting the lid lay on that for a bit. Madts’ idea sounds more controllable than trying to sponge down the board manually. Thanks!

-- HorizontalMike -- "Woodpeckers understand..."

View Dallas's profile


3599 posts in 3372 days

#6 posted 09-04-2013 12:04 AM

Mike, look at your end grain…..

Those boards were cut from almost the center of a farm raised tree.
The closer you get to the center, or ‘pith’, the more they will cup, bow, crown, split and cause general havoc with your plans.
No matter how much you wet and press they are going to cause problems.

-- Improvise.... Adapt...... Overcome!

View HorizontalMike's profile


7898 posts in 3799 days

#7 posted 09-04-2013 12:31 AM

Yeah, I was wanting to slap this together on the cheap side, hence trying the construction SYP. Live and learn.

Hmm… I still have a bit of 8/4 Ponderosa Pine left that I might try to use, but it is really full of large knots. I am going for the rustic look, so who knows…

-- HorizontalMike -- "Woodpeckers understand..."

View Mark Shymanski's profile

Mark Shymanski

5623 posts in 4597 days

#8 posted 09-04-2013 12:44 AM

I had a 10 foot length of spruce 2X6 that has been sitting in my shop for about 4 years. Ripped it yesterday and it corkscrewed on me. I don’t think it is just a humidity thing, I think Dallas has something with respect to the internal stresses in the wood…...I think Gerry has the best idea LOL!

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

View Dallas's profile


3599 posts in 3372 days

#9 posted 09-04-2013 01:04 AM

I love Ponderosa Pine… Especially the knots.
If the the knot is tight, see if you can suck some epoxy into it with a vacuum on the backside.
If the knot is loose I use Bartop finish, basically a thinner version of an epoxy.
I usually use 3 or 4 layers, but have done a single layer 1/2” thick before…. just use a blow dryer to pull the air bubbles out or they’ll show up when it cures.

-- Improvise.... Adapt...... Overcome!

View WDHLT15's profile


1819 posts in 3361 days

#10 posted 09-04-2013 01:12 AM


The problem was that the wood was not dry to the extent we expect for building furniture. Construction SYP lumber is generally dried to KD19, which means kiln dried to 19%. The reason the top cupped is that it is still drying in your shop, and one side got more air and dried faster than the other side. If you manage to straighten it back up, it would best to let it dry for a few weeks in the house before finishing. Be sure to let the top get air equally on all sides.

-- Danny Located in Perry, GA. Forester. Wood-Mizer LT40HD35 Sawmill. Nyle L53 Dehumidification Kiln.

View redSLED's profile


790 posts in 2777 days

#11 posted 09-04-2013 01:15 AM

Just FYI, over the years for pine tables I’ve bought from HD their sometimes available 1”x12”x8’ rough planks of kiln dried white pine at very reasonable cost here in Ontario, CA. Being pretty soft it’s easy planing them after about 4 weeks of drying in the garage, and I’ve never had big issues with cupping and twisting prior to assembly (as opposed to the SYP planks). Not sure if your HD stores in Texas get those white pine planks though.

-- Perfection is the difference between too much and not enough.

View Dallas's profile


3599 posts in 3372 days

#12 posted 09-04-2013 01:20 AM

Mark, Spruce is notorious for reaction wood… We use to take the S out of the SPF studs we framed with and put them in the morning burn pile….. Shhhhh…. The GC would have had a fit if he knew!

SYP is a bit different. If you are ever in the Carolinas, Georgia, Alabama, Mississippi or north Florida, there are a lot of SYP farms… They are easy to spot, trees 5 to 20’ apart, farther apart as they get older due to thinning.
They have irrigation systems and only grow about 20 years before they are cut.
Syp on a farm is a lot different than the SYP of the olden days. That was a very dense wood, very stable and had tight rings from natural causes.
Notice the thick growth rings on the wood you buy at the box stores. The smaller the radius of the rings, the closer it is to the core.
The wood is grown so fast that it cannot support itself. Without the water and stuff they feed it with, it would have a difficult time surviving.

We have 5 Loblolly pines here at the campground. They are 63 years old and look really ratty because they’ve never been ‘groomed’. When these trees die they will make wonderful lumber and basically they are the same species as the SYP in the southeast.

-- Improvise.... Adapt...... Overcome!

View HorizontalMike's profile


7898 posts in 3799 days

#13 posted 09-04-2013 01:45 AM

Perry: ”... Construction SYP lumber is generally dried to KD19, which means kiln dried to 19%. The reason the top cupped is that it is still drying in your shop, and one side got more air and dried faster than the other side. ...”

I think you are on to something there. I do remember thinking about just how heavy these boards were when hand picking them at HD. 19% huh, well that makes sense.

Plus, I had the lid on opposite of the image for the first 24hr (no weights) and the lid cupped upward on the sides, so I flipped it and put on the 70lb of weight. Now thinking inside of box is drying slower because of lid making it a closed environment.

And guess what now, 2hr later and temps dropped to 95F (from 108F)


THE LID NOW HAS FLATTENED! I am now thinking I should sticker this lid with weights on top for some more Texas Heat drying time on both sides. And that would allow the entire chest carcass to breathe internally too. I guess I really did not expect to see so much drying in such a short time frame.

BTW, the front and back boards are now bowing outward ever so slightly. I guess maybe I should also put a partition down the center of the interior to pull them back in. The bow is only about 1/8in so far and I don’t think making the chest a double compartment is a big thing. This chest was supposed to double as additional seating anyway, so having additional support across the span couldn’t hurt.

-- HorizontalMike -- "Woodpeckers understand..."

View MT_Stringer's profile


3183 posts in 4116 days

#14 posted 09-04-2013 02:03 AM

Mike, how about some good old white pine?

-- Handcrafted by Mike Henderson - Channelview, Texas

View HorizontalMike's profile


7898 posts in 3799 days

#15 posted 09-04-2013 02:27 AM

”...Mike, how about some good old white pine?...”

I recently made a second narrow Amish cabinet(green one) with HD White Pine (the first was Ponderosa Pine) and found it to be really really soft. Almost PITA soft, especially when trying to do handcut dovetails. I think I made 6 attempts before getting an acceptable set. Other than that I guess WP is OK. It sure takes a light hand to work with though.

-- HorizontalMike -- "Woodpeckers understand..."

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