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How to Stop End Checking in Lumber

Lumber is stacked on sticks like this to allow air flow for drying.

End checks are a common problem when drying wood. Sometimes they aren’t too destructive and don’t travel too far, but other times they make the end of the lumber completely unusable or make a nice wide board into two not-so-wide boards. These cracks form on the ends of lumber because the ends are drying out faster and shrinking more than the middle. This happens because water can easily and quickly escape out the end, which is the same way it came in, but water trapped in the middle must travel out sideways to escape, which is a much trickier maneuver.

The secret to keeping lumber from checking on the ends is simple and logical – force the ends to dry out at the same speed as the rest of the board, meaning slow down the drying on the ends. Unfortunately, there is no single, 100% effective, way to do this.

The default method for beginners is to paint the ends with latex paint. Latex paint will not stop end checking because it it just too permeable. It will make you feel good, like you are doing something useful, but that’s about it.

Beyond latex paint is wax and unlike latex paint, wax is waterproof. If applied in a thick cohesive film, wax forms a perfect barrier to keep water from moving out of the end of a board. The biggest problem with wax is application. It is just hard to get hot wax on to the end of a lot of lumber in a timely fashion.

Anchorseal is an industry standard for green wood sealing of logs and lumber. (Click on the photo to visit UC Coatings website for Anchorseal)

The application issue has been addressed by the kids at UC Coatings, who make a product called Anchorseal. Anchorseal is a wax and water emulsion made exclusively for coating the ends of logs and lumber to help prevent end checking. Anchorseal works just as stated, but it isn’t perfect.

First, Anchorseal isn’t cheap. A five gallon bucket goes for about $95. It costs enough that I thoroughly consider whether the wood deserves it. I usually save it for only the best lumber and the species most prone to checking, like white oak. Second, it still takes time to apply, and it is pretty messy. I know several guys that won’t use it in their operations because it gets on the floor and makes everything so slippery that it can be difficult to stand up. Third, using Anchorseal doesn’t guarantee that your wood won’t split. While it will greatly reduce the overall number of end checks, it isn’t uncommon to still get one or two big checks in wide boards. Many pieces of lumber have flaws in them and will split during the drying process no matter how much you try to stop them. Fourth, it must be applied to freshly sawn lumber before the end checks have started to develop for maximum effectiveness.

You can tell from my four points above that I don’t use Anchorseal very often. But, there are places that I will use it, and one is on high-quality, especially thick, flat-sawn white oak. Again, it may not stop all end checking, but it is a great tool to help prevent much of it. On many other species, like poplar, maple, and even walnut, I feel like I usually get by with minimal losses not using Anchorseal. It should be noted that my customers are usually shopping for small quantities of lumber, so they can decide on a board by board basis if an end check is problematic for them. For operations sending out large amounts of lumber to customers that are not picking through each board, using Anchorseal makes the most sense to help produce the greatest amount of useable lumber out of each bunk. At the very least, sealing the ends of the lumber lets your customer know that you did try to prevent end checking.

Fluted sticks are commonly used in the industry to promote drying and reduce sticker stain, but do nothing to reduce end checks.

My greatest gains fighting off end checking have occurred in my sticker selection and placement. While many strides have been made in the industry to produce fluted sticks that reduce sticker stain, very few people have given much thought to using stacking sticks to help reduce end checking.

Awhile back, while at a friend’s sawmill, he casually mentioned how he noticed that lumber will split on the ends, back to the first stick. He was mad that his guys where producing lumber piles that weren’t so neatly stacked, but I focused on the end checking. After that, I paid more attention to my own stacking and changed how I stacked lumber.

Place wide, solid sticks on the very end of lumber stacks to reduce end checking.

The main difference was that I started using the sticks on the ends of the lumber to reduce end checking. I focused on getting the sticks out to the end of the lumber, and I also made sure the end sticks were solid sticks, which help hold in moisture, even on sticker stain prone woods like maple. Since the ends dry out quickly, they don’t sticker stain, and even if they did the loss on the end of the lumber would be minimal. Beyond using solid sticks, I also use wider sticks on the ends, up to 3″ wide. The extra width helps hold in even more moisture and still doesn’t risk staining the ends.

In my opinion, focusing on placing wide, solid sticks at the ends of the boards is as effective as end sealing, especially in relation to cost and time savings. Again, this isn’t a perfect method, but you would be amazed at how well it works to reduce end checking. And, if you have some especially prized lumber, you can rest easy knowing that you can always add AnchorSeal to the mix to double your chances of check-free lumber.

 

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Don’t Screw (up) Your Wood Top

Recently, I got a question from a customer regarding a crack forming in his solid wood countertop. He built the top out of flat sawn white oak lumber and he wanted to figure out what caused the crack and hopefully, how he could repair it. Luckily, the repair is simple (just some glue and clamps), but he really needed to address the cause of the problem or the countertop would most likely crack again.

This countertop split in the back corner because it was screwed firmly in place and couldn’t move.

This view from inside the cabinet shows how the top was attached with no room for movement.

When he sent me photos of the crack, he also sent me photos of the how he attached it to the cabinets, which was very helpful. The vintage metal cabinets have a bracket in each corner with a hole just large enough for a screw, but not large enough to allow for any movement in the top. In this case, the wood was stuck in place and had no choice but to split when it shrunk in width.

I recommended to simply make the holes in the metal bracket bigger and to add a washer or use a large-headed screw to allow the top to move side to side while still being held down. The secret is to tighten the screws just enough to hold the top in place, but loose enough to allow it to move if the wood starts to pull.

This particular solution was pretty simple, but only because I have seen it many times before, and I knew what caused it. Without understanding how wood moves, the diagnosis wouldn’t be so apparent. Even though most people don’t worry about wood movement as much as I do, I always try to get them to understand the most basic premise, which is that wood moves more in width than it does in length, and you need to allow for that movement.

In woodworking in general, this disparity in movement is referred to as a “cross-grain situation”, when two pieces of wood come together with grain perpendicular to each other, then they want to pull in opposite directions. It happens all of the time in furniture construction, and it must be addressed to avoid catastrophic failures. In the example above, the setup was the same as a cross grain situation because the metal cabinet will not change in any dimension, while the wood moves in width.

When attaching wood tops of any kind, whether it be a wood countertop to a cabinet or a table top to a table base, you need to allow the top to move or it can split. The good news is that there is more than one way to attach a top and still make allowances for this movement.

The first and most common way, as mentioned earlier, is to make an oversized or elongated hole and to make up any differences with a washer or large-headed screw. Assume that any problems will be caused by excessive shrinkage and make sure that your holes are big enough and that your screws are placed in the holes so that the top has room to shrink.

It easy to make blocks like this for attaching tops. The screw is firmly in the block, but the lip on the block can slide if the top pulls hard.

Another method, which I like to use on tables, is to make blocks to fit into dados on the insides of the aprons. They don’t take too long to make and can easily be added wherever necessary. The blocks should be made so that tightening up the screws will just pull the top snug, like a perfect fitting tongue and groove joint and placed with a little separation to make sure nothing binds. They work great, and I think they look great too.

When attaching a top with a propensity to move, understand that all of your attachment points don’t have to have play in them. For example, you can firmly attach a countertop to the front of a cabinet as long as you allow the top to move in the back. Or, on table tops, you might choose to firmly attached the top in the middle of the width and allow the outside edges to move. This is perfectly acceptable and keeps the top centered on the base.

The main point to remember through all of this is to allow the wood to move. You can only really cause a problem if you don’t allow it to move. And remember , if you find that it is moving too much for your liking you can always go back and firm things up once you understand the potential problems.

For a more thorough description of wood movement click on these two earlier posts Have Your Heard About Shrinkage? or Why Quartersawn Lumber is so Stable: The 0-1-2 Rule In Action, to read a link on the subject. I think it is probably the most important subject for any woodworker to fully understand.

 

Why Not Mill Pin Oak?

On a regular basis, probably at least once a week, someone contacts me looking to have a pin oak milled into lumber. They are excited because they finally got their hands on a truly giant specimen of a tree, and even though it is just a red oak, they are excited to get to work with a hardwood at a reasonable price. Unfortunately, I have to be the bearer of not-so-good news and try to get them to reconsider.

This pin oak is less than 20 years old and is already over 15″ in diameter.

As I mentioned, pin oak is in the red oak family, but that is about the only relationship it has to any decent red oak lumber. Pin oak is not milled and sold commercially under the name red oak, and as far as I know, is only used for low-grade products like pallets and blocking, where the only requirement is that it be made of wood that will stay together. And funny enough, pin oak often falls short of even that low requirement.

The problem is that many pin oak trees suffer from ring shake, which is where the rings of the tree peel apart like an onion, making that section of lumber nearly unusable. The beauty of ring shake is that it can’t be seen from the outside of the log and it won’t always be visible even early in the milling process. Sometimes, it won’t be until the lumber has been fully processed and dried for it to start falling apart. Needless to say this is frustrating, especially if you are counting on that lumber for a project and then end up with no wood to work. Even if the ring shake isn’t bad enough to make the lumber actually break, it very often leaves at least one fancy break line somewhere in a board where you would rather not have it. Again, super frustrating.

So, let’s say you find a pin oak that is solid, with no ring shake, then it is all clear sailing, right? Far from it. You may have lumber, but you probably don’t have great lumber. One of the main attractions for pin oak is the giant size and the promise of a never-ending bunk of lumber comprised of super-wide boards. This, you may indeed have, but it comes at a cost. The cost is that all of the super-wide lumber will have super-wide growth rings, rings that may be up to 1/2″ or more in width. Because the tree grows so fast, putting on up to 1″ in diameter per year, the logs get big in a hurry too. It isn’t uncommon for a 36″ diameter log to have only started growing 45 years ago. It was planted because the trees grow to a large, stately appearance quickly, and that means big, wide growth rings.

Big growth rings mean a coarse textured wood, no matter how you cut it. Whether flatsawn or quartersawn, red oak is already known for its open, in-your-face, grain, and pin oak is ten times worse. Imagine an 8″ wide flat sawn board that may only show a couple of annual rings on the face. It looks more like the cheapest of spiral cut plywood for sheathing the side of your house, instead of quality hardwood lumber for building fine furniture. That same 8″ wide board, if quartersawn, will probably show about 20-25 rings, where a high quality white oak board will show 60-80 rings. The difference is night and day, with the higher growth ring count looking much more refined and not so clunky.

Even if the wood stayed together and for some reason the growth rings weren’t so wide, pin oak would still be far from a great hardwood. The lumber typically also sports bad color, bad smell (commonly referred to as “piss” oak by local tree guys), and many more knots than are outwardly apparent. Since the trees are usually open grown and well pruned, the always straight, always perfectly upright trunks appear to contain up to 30′-40′ of clear lumber. The truth is that the trunks typically contain only 8′ of clear lumber near the ground, with the remainder being full of knots from previously trimmed branches.

Overall, I have nothing good to say about pin oaks, except that they grow big, tall and straight. And, while it may be possible to mill pin oak lumber that meets some minimum requirements (like staying together), the best pin oak is still easily surpassed in quality by almost any other reputable wood. Just know, if you are thinking about paying someone to mill a pin oak tree for you, that I wouldn’t even mill a pin oak if it magically fell on my sawmill. I would take the extra time to get it out of the way, so I could mill something better. It’s just not worth it. Move on.

Lucas Sawmill Is Small But Mighty


Scott Wunder of WunderWoods laying on giant white pine live natural edge milling

My sawmilling adventures began with an Alaskan chainsaw mill, which is just an attachment for a chainsaw to allow it to repeatedly cut a log lengthwise into lumber. It wasn’t anything fancy, and while it produced fine lumber, it was painfully slow to use. It didn’t take too many hours of me directly sucking in sawdust and fumes, while sweating my butt off, to start shopping for a more capable sawmill.

When I started my search, I considered bandsaws made by companies smaller than Wood-Mizer or TimberKing or Baker in a quest to also find smaller prices. While searching, I found several mills that looked suitable in the $5,000-$10,000 range, and I also came across a new “swing mill” from Australia called a Lucas mill.

The bandsaws looked to be a good choice as far as production went, but I didn’t have any way to move logs at the time, so the Lucas won out. It’s ability to easily break down and set up on site, while fitting in the bed of a pickup truck made it the clear choice, especially for larger logs. I say clear choice, but it wasn’t an easy choice. I didn’t like that the basic mill, fitted with a circular blade, was limited to 6″ or 8″ wide lumber without the optional slabbing bar attachment. And, my biggest fear was that this new mill from Australia, that I knew nothing about, might not be as good as it appeared in the videos.

Unfortunately, my fears were NOT immediately allayed. I went to pick up the more than $10,000 sawmill at the shipping terminal, and I couldn’t help but feel like I way overpaid for the amount of merchandise I picked up (Did I mentioned that it fits in the bed of my pickup truck?). There was only a sawhead, two long rails, and a few other miscellaneous metal parts that formed the frame ends. Besides that, the kit included a sharpener and some other odds and ends, but none of it added up to very much. I started doing the cost per piece arithmetic in my head, and it wasn’t looking good.

Here I am reading directions and setting up the 6" Lucas mill for the first time.

Here I am reading directions and setting up the 6″ Lucas mill for the first time.

Regardless of my buyer’s remorse, I was tickled to have a “real” sawmill and set it up in my back yard the very first chance I got. After just a short time reviewing the directions, I had the sawmill set up and ready to cut. Even for someone who had never set one up, the Lucas went together fast. It was then that I realized what I had paid for. I didn’t pay for lots and lots of parts and extra bulk. I paid for an impressively designed machine, with an amazingly small stature, than can tackle the biggest logs. I paid for all of the research and design that went into the mill by the Lucas boys, and I paid to not lug around thousands of extra pounds, and I paid for everything to go together with minimal effort and a minimal number of steps. I got all of that and more.

From a design standpoint, I can confidently say that every part of the Lucas mill is well-planned and simplified beyond belief. The only mechanisms that I have ever had a problem with are the winches that raise and lower the ends of the long rails. They work perfectly fine and they are quite smooth, but they can be dangerous. When fully loaded with weight, it is possible to release the winch and lose control, resulting in a violently swinging handle that can smash your arm and allow the sawhead to come crashing down. I know from personal experience, as this has happened to me more than once, with the last instance leaving me at the hospital with a possible broken arm (luckily it was just a very bad contusion). If they were to ask, I would recommend that the winch system be built like the raising and lowering mechanism on my TimberKing 1220 manual mill, which magically is able to easily raise and lower the sawhead with complete control and without the possibility of having a disastrous crash. I have no idea how it works, but it smoothly operates the sawhead with a very heavy 15 hp electric motor attached to it like it isn’t there at all.

Even logs this size, like the one I milled for Martin Goebel of Goebel and Co. Furniture can be milled with the Lucas mill.

Even logs this size, like the one I milled for Martin Goebel of Goebel and Co. Furniture can be milled with the Lucas mill.

Now that you know to watch your arm and to be careful when lowering the sawhead on the Lucas mill, I can continue telling you how wonderful the Lucas mill is. First off, realize that I bought a Lucas mill in 1995, so I have been using one for about 2o years now, and I still use it on a regular basis. It is a very versatile machine that can handle big logs with ease. I often get asked how big of a log I can handle, and with the Lucas mill in my corner, I can just answer, “Yes.”

Currently, I use the 8″ model, which means that with the 21″ diameter circular blade attached it can produce up to 8″ x 8″ dimensional lumber. I rarely cut 8″ x 8″, but the mill can easily be adjusted to cut any dimensions under 8″. I often cut 1″ and 2″ thick lumber by 8″ wide.

The Lucas mill is called a “swing” mill because the blade can flip or swing with the pull of a lever from the horizontal to vertical position and right back again. The cool part is that both of the cuts line up with each other and work in concert to produce accurate and straight, completely edged lumber without a dedicated edger or any extra handling. In contrast, to edge lumber on a bandsaw mill requires flitches (lumber with bark edges) to be stood up in the mill and cut one or two more times to produce lumber with four square edges.

In the 1990's, I used the 6" Lucas mill to produce lots of 1" thick, fully-edged lumber.

In the 1990’s, I used the 6″ Lucas mill to produce lots of 1″ thick, fully-edged lumber.

When cutting dimensional lumber I can easily work by myself making the vertical cut walking backward, then making the horizontal cut walking forward and finishing by sliding the cut board backward and out of the way. After a quick repositioning of the sawhead and a flip of the blade, I am back to cutting another piece of lumber. When cutting dimensional lumber like this I get in a rhythm–walk backward, flip blade, walk forward, slide board, move and flip blade, then repeat. The first cuts on the outside of the log are firewood, but after one pass across the top of the log and then dropping the mill to the next set of cuts, almost every pass produces an edged piece of lumber.

Scott Wunder of WunderWoods milling a large white oak slab on the Lucas mill for Martin Goebel of Goebel and Co. FurnitureWhen I first got my Lucas mill I used it with the circular blade most of the time. Everything I produced was fully edged. Big slabs weren’t in style, so I didn’t even own a slabber, let alone use one. Now things are different. Live edges are in and so are big slabs, so the slabber is on the mill most of the time. The slabber is an attachment that turns the sawhead into a giant 2o hp chainsaw mill, with a maximum cut of 64″ wide.

I use the Lucas mill with the slabber attachment to cut all of my big logs that will produce slabs for table tops. With the slabber attachment the Lucas is not fast, but it can cut much wider than my bandsaw mill (maximum cut of 29″ wide), and it doesn’t make sporadic wavy cuts like the bandsaw mill. Knowing that I won’t get a miscut on a high-priced piece of wood gives me a great piece of mind.

The Lucas mill is great at flattening live edge slabs too.

The Lucas mill is great at flattening live edge slabs too.

These days when the slabbing attachment isn’t on the mill, the circular blade is, but not for milling lumber. I have been using it to flatten my kiln-dried slabs, and as long as the blade is sharp, it works great. After I move the slab into position, I just skim the surface with the mill to remove the high spots. Next, I flip the slab, drop the mill a bit and skim the other side. The end result is a perfectly flat slab, ready for final planing. The kids at Lucas sell planing and sanding attachments, but I haven’t used or purchased either one since I finish almost all of the slabs with the power hand planer or wide-belt sander.

Every time I use the Lucas mill, I am reminded how well it works, from quickly setting it up to making small adjustments, everything is simple. And, I know when I show customers how capable it is, they are impressed that such a lightweight, easy-to-setup mill can do so much.

Note: While Lucas is more than welcome to pay me to endorse their mills, as of now they do not. This was written for educational purposes and to let others know how my slabs are produced.

 

Antiques Roadshow Find or Nakashima Knockoff?

Last week a friend of mine, John, was at my shop telling me about a chair that he found on Craigslist. It wasn’t in perfect shape, and the wood was stained with red blotches that he said looked like Kool-Aid, and he joked that they were more likely blood. It was, however, well built, in good shape overall and had not been repaired, so he shelled out the asking price of $20.

After getting the chair back to his house, John quickly got to work sanding on the chair by hand to remove the stains and then followed the sanding with a little Danish oil to make the chair look like new.

This is how the chair looks now, after the stains were removed.

This is how the chair looks now, after the stains were removed.

I’m not sure exactly how it happened and I don’t know that it is important to the story, but another friend of ours stopped by John’s house and between the two of them they realized that the bottom of the chair seat was signed. Luckily, John hadn’t sanded the bottom of the seat and everything that was written on it was still very clear. They found, in large letters, lightly written in pencil, an inscription that says “Cotton Rocker” and in bold, black ink what appears to be, “George Nakashima, March 1974”.

Pencil layout lines and markings, a few red stains and a brushed signature on the bottom of the seat.

Pencil layout lines and markings, a few red stains and a brushed signature on the bottom of the seat.

Looks like "George Nakashima, March 1974" to me.

Looks like “George Nakashima, March 1974” to me.

It didn’t take long after hearing the story for me to end up at John’s house, so I could see the chair for myself. I wasn’t expecting much and imagined that I would know right away that the chair wasn’t a legitimate Nakashima, not because I am a Nakashima expert, but because I know wood and something was bound to be obviously wrong with the materials or construction.

My initial concern was that John destroyed any possible value with a wild bit of overly aggressive sanding, but that wasn’t the case. The chair looked great, and after a little more interrogating, I discerned that it didn’t take much work to remove the stains. And, though it didn’t necessarily help, nothing John did permanently damaged the chair.

After I gave the chair a quick look, I plopped myself down and took it for a test rock. The chair is a bit low for me, but it makes sense for someone who is probably a foot shorter, like Mr. Nakashima himself. Both the seat and back are wide and provide great support while still being flexible and comfortable. As a matter of fact, it is probably the most comfortable, all-wood chair that I have ever sat in.

I sat and rocked for a short time while we talked more about the chair and my disbelief that he found it on Craigslist for $20. It was beginning to look like it was the real deal, but even if it wasn’t, the price was fantastic for a chair of this quality. He definitely did not overpay.

After I rocked for a bit, I decided to really do some detective work. I started by looking closely at the wood. The walnut had the right patina for being around 40 years old and the spindles were made of hickory, which later research verified was appropriate.

The only thing that seemed odd to me was the wood selected for the seat. When I think of George Nakashima, I think of wood and the way that he respected it and the way that he would make sure that the wood was selected with as much care as the actual construction – this seat seems to be less so. While not wrong, the seat is composed of seven pieces of walnut that appear to be selected on a Friday just before quitting time. I imagine Nakashima making his seats out of a single piece or two pieces of matched woods and it looks like this walnut wasn’t even from the same tree, which is a bit hard for me to swallow, especially knowing that Nakashima was known for having plenty of wood on hand.

Everything else about the chair oozes quality and makes me believe that it is a Nakashima product or was made by someone who appreciated his work and tried hard to duplicate it. All of the proportions are well-found, with a great balance between strength and delicateness. The hickory spindles are almost dainty, but offer more than enough support to the backrest, which is equally small, but more than adequate. The details that I really noticed and appreciated, are the two spindles that extend through the top of the backrest. They protrude so little that they are almost unnoticed, but they reach up just far enough to be a detail that connotes fine craftsmanship.

The overwhelming clue to me that this may truly be a Nakashima piece of woodwork is that the chair is 100% solid, with no signs of loose joints or repairs. It is a testament to the fact that this chair was built with care from the original maker, which I am guessing is George Nakashima or someone who spent lots of time with Mr. Nakashima.

While doing a little research on Nakashima and trying to find a photo of a similar signature (which I did not), I found some recent examples of authentic chairs that have sold at auction. It looks like similar chairs, like the one below, are selling currently for between $2,500 and $10,000. I assume that John’s chair will be at the lower end of the spectrum, even if it is found to be the real thing, since it is not in original mint condition. Even so, it is a heck of a find for $20.

This Nakashima rocker recently sold at auction. Except for the armrests, John's looks very similar. (Photo from Skinner Auctions).

This Nakashima rocker recently sold at auction. Except for the armrests, John’s looks very similar. (Photo from Skinner Auctions).

John plans to keep the chair and enjoy it for now. I told him that I thought it was a great idea because I don’t see it going down in value and it will give him time to try to find out more about that specific chair.

If you have any insights on how to determine the legitimacy of this piece, we would love to hear about it. I know John would love to determine if it is an actual Nakashima chair. I guess he could always go on Antiques Roadshow and find out for sure.

Update (3/5/17):
John heard back from the kids at Nakashima and it turns out that it is an original. They even have the original paperwork and will authenticate it for him. Lucky John!

Grow Exhibit Opens at the St. Louis Science Center

The Exploradome (above) was deflated and removed to make way for the new Grow exhibit. Click on the photo to find out more about the now deflated Exploradome.

The Exploradome (above) was deflated and removed to make way for the new Grow exhibit. Click on the photo to find out more about the now deflated Exploradome.

If you have driven down Highway 40 in St. Louis recently, you may have noticed a new structure being erected next to the St. Louis Science Center where the “temporary” Exploradome once stood. After 16 years in service, the inflated building was past its prime and too expensive to operate, so it was replaced with a new, permanent agriculture exhibit called Grow.

The centerpiece of the exhibit is the new building that features massive bent laminated beams which create a beautiful swoosh of a roof. Just outside the entrance of the new building is a vermiculture display that I built for the exhibit. While it pales in comparison to the woodwork that went into making the building, I like to think it makes a nice little earth-friendly welcome mat for visitors.

The bent laminated beams that make the roof structure on the new Grow exhibit building are impressive.

The bent laminated beams that make the roof structure on the new Grow exhibit building are impressive.

The vermiculture unit, designed by Mark Cooley, uses worms to make compost. Built out of locally salvaged Eastern Red Cedar, the two-compartment structure is set up to have green waste loaded in the top and compost extracted from the bottom after the worms have done their job eating the contents. The two compartments, which are side by side, are divided by a wire mesh that allows the worms to move between compartments. This particular unit has glass panels to allow for viewing of the interior from the front of the display, though the glass is not required for use.

Just outside of the new building is the vermiculture unit where worms make green waste into compost.

Just outside of the new building is the vermiculture unit where worms make green waste into compost.

This project was a bit out of the norm for me since it was more carpentry than fine woodworking, but it was a fun change to build something that wasn’t so fussy. I had the most fun when I was able to find some logs in my shop already standing against the wall for the project. They were left over from another project, and I was able to just carry them to the sawmill and cut the parts I needed. I chuckled to myself while I was doing it because I have never just hand carried logs to the sawmill that were standing in the shop like sticks of lumber. It was only possible because cedar is lightweight and the logs were small, but I still had more than enough to make this project.

Cedar is lightweight, durable and cuts like butter.

Cedar is lightweight and durable. I already had these logs in the shop waiting to be milled.

Mermaid Lagoon driftwood sign WunderWoods

The vermiculture unit was a bit more fussy on measurements, but it reminded me of making this sign.

Cedar mills like butter on the sawmill, even when dry, and since it was going outside I didn’t need to do any extra drying. I was able to mill it, plane it and assemble it right away, which made it feel more like I was building a fort or a treehouse, especially since I never get to knock something out like that. It reminded me a lot of the Mermaid Lagoon sign I made for Mira a few years ago, since both went together expeditiously. There were a few critical measurements to maintain, like the size of the footprint, but everything else was somewhat negotiable as long as it looked and worked like Mark Cooley’s design.

The vermiculture unit is nestled in the Grow exhibit along a mulch path surrounded by plantings that are arranged like a garden or small farm field. Nearby are live chickens, two new tractors, a greenhouse and a dairy demonstration area. Inside the building are electronic, hands-on displays that focus more on the places that generate food, from the species of plants to different farm settings. Outside, on the North side of the building, are a couple of displays that focus on water, with a chance for the kids to interact with displays that are both hands-on and hands-wet.

The St. Louis Science Center and the new Grow exhibit are free to all visitors. It opens Monday-Saturday at 9:30 a.m. and Sunday at 11:00 a.m. The Science Center closes at 5:30 p.m. during peak summer hours (May 28-Sep. 5, 2016) and at 4:30 p.m. during off-peak hours.

 

Today’s Glues are Super Strong

When customers stop by to peruse the lumber and slabs I have for sale, they inevitably end up near the back of my shop, where I do my woodworking. They like to see what I am up to and discuss woodworking in general. Lately, I have been making a lot of live-edge tops, so I usually have at least one being glued up, and I can guarantee you that the first question is going to be, “What do you use to join those two pieces of wood together?” They are expecting a dramatic answer full of technical jargon, like tongue and groove or sliding dovetail or dominos or even biscuits, but I always disappoint them and just say, “glue”. I like to say it in a sort of caveman fashion for dramatic effect and a bit of humor, but then I quickly jump in and fill the awkward silence with a more detailed explanation, especially since I can tell that just blurting out the word “glue” isn’t going to be enough.

I use Titebond original wood glue with the red cap. There is Titebond II and III for more water-resistency, but I usually stick to the original unless it is a project that is prone to getting very wet. I like that the original cleans up easily with water and that even dried glue can be soaked and removed from brushes and clothing. I don’t prefer Titebond for any special reason, except that it is widely used and widely available. I would just as confidently use other name-brand wood glues and expect similar results.

 

I use Titebond original wood glue (with the red cap) and clamps on sawhorses. For big tops, I ditch the sawhorses and just use the floor.

I use Titebond original wood glue (with the red cap) and clamps on sawhorses. For big tops, I ditch the sawhorses and just use the floor.

 

Spectrum Adhesives MG-1000 industrial-grade PVA glue is all they use at Goebel and Co. Furniture (along with a JLT clamp rack) to assemble panels and tops like these.

Spectrum Adhesives MG-1000 industrial-grade PVA glue is all they use at Goebel and Co. Furniture (along with a JLT clamp rack) to assemble panels and tops like these.

The glues available today are strong, super strong, stronger than the wood itself. To prove this, I always save the end cuts from my glue-ups, so I can break them later for demonstration purposes for customers and inspection purposes for myself. If the glue is fully dry (results are not guaranteed if the glue is still wet), the glued-up scraps will always break somewhere in the wood. Even if it does happen to spilt close to the glue line, there is always plenty of wood stuck to the glue to make anyone doubting the strength of the joint to become a believer.

In comparison, I have worked with plenty of reclaimed wood, especially old oak church pews, that have a tendency to split along the glue joints. When closely inspected, it is clear that the old glue had become dry and brittle, and though it stuck to both surfaces, the glue itself broke down, like old plastic that has been outside too long. Most likely, the older glues, while strong at the time, weren’t formulated correctly to stay flexible over time. Current glues are formulated to hold strong and not break down during regular indoor use. Note that I wrote “indoor” use – for outdoor use, all bets are off. From extreme wood movement to glue breakdown, there is simply too much wear and tear outdoors for the glue to hold a jointed edge together on its own without any eventual failures.

So, we know that the glue is strong and is more than capable of holding a joint together, but just how strong is it? There is probably some value on some fancy scale to tell you exactly how strong the joint is, but it doesn’t really matter, as long as you know that it is stronger than the wood. At that point, to know the strength for sure, you would need to know the strength not only of the wood you are working with, but the weakest point in any given spot in a board, which you just can’t know, so I say stop worrying about it. Just know that it is more than strong enough to do the job.

Now, for the glue to work correctly, your machining and joints need to be reasonably good. I say, “reasonably” good because I think there is a lot of wiggle room here. Obviously, if everything is perfectly square and straight, there is no question about your joint integrity. You can simply coat the joint with glue, apply just enough pressure to pull everything together, and you will end up with a strong, wonderfully impressive joint. But, what if your jointed edges are square but the boards are long and have a bit of a bow and they will require a bit of extra clamp pressure to pull them together, is that gonna work? Heck yeah! Did I mention the glue is strong? A little extra clamp pressure is fine.

What about a lot of clamp pressure? Now this is where the “reasonably” good part comes into play. I say if you are doing a glue-up and you feel like you have applied so much pressure to pull things together that it just feels wrong, then you should probably work on the joint some more. But, here’s the kicker. I can tell you that I have been involved in more glue-ups than I should admit to that have required an inordinate amount of clamp pressure, and to this day (knock on wood), I have never had a joint fail. Maybe I have just been lucky, since I have done tons of glue-ups, but I use this as a real world testament to the strength of the current glues.

The problem with needing a lot of clamp pressure to pull joints together is two-fold. The first issue is that there are built-in forces that are always trying open the joint with the same amount of pressure it took to close up the joint, which can be significant. The other issue, and the one that is commonly more worrisome, is that more clamp pressure means less glue in the joint. The concern being that if all of the glue is squeezed out then obviously there is nothing to hold the wood together. As far as I can tell, especially since I have not had a failure yet, is that this isn’t easily accomplished. I am not saying it isn’t possible, but it isn’t easy. Many woods have open pores that will hold glue no matter how much pressure you give them (think oak and walnut), and if you are fighting at all to pull a joint together, that means that somewhere along the line things are loose enough to hold some glue. Sure, it might completely squeeze out in one spot and make the joint a bit weaker, but in other spots the glue will hold like it is supposed to and keep things from coming apart.

With all of this cavalier talk about crappy joints with extra clamp pressure, you still have to show some restraint. There are going to be times when you can’t rely on just the glue, no matter how strong it is, to hold everything together and you will need to rework your joints for a better fit. A couple of instances come to mind. Some woods have very tight grain that is smooth and won’t hold much glue (think hard maple), so it is possible to end up with a joint that has almost no glue in it. The second instance where more jointing work will be required is if the boards are tight in the middle and loose on the ends. The ends are where a top will want to naturally split, so trying to use extra pressure in this case, is inviting an issue down the road. I feel a million times more confident closing up a gap in the middle of a glue-up than I do the ends, knowing that the entire joint is holding things together, not just the glue on the ends.

One last category that requires a little extra attention is exotic wood. Some have oils in them that just won’t glue properly. They need to be cleaned with lacquer thinner before gluing to provide a good surface and they are often extra hard, so they don’t absorb much glue. I have had problems with bloodwood in the past, which fell apart during my initial tests because I had not cleaned the wood enough. To be safe, I cleaned the wood even more and roughed up the surface a bit with sandpaper to give the glue something to grab. Before the sanding, the edges were just too hard and too smooth. Since then, the extra hard and oily exotics scare me, so I would never force a glue joint with them. I trust the current glues a lot, but there are limits.

Assuming that you have decent joints and wood that will accept glue, all you have to do is make sure that both surfaces are coated with wood glue and clamp them together until the seam is tight. That is really all there is to it and all that is done at almost every professional shop I can think of. You don’t need any special tricks at all, just “glue,” I remind you in my caveman voice.

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