Making Wooden Roubo Try Squares
Chris Schwarz showed us how to make Roubo-style try squares in the February issue of Popular Woodworking. These have the virtue of being easy to make in any size desired, are half the weight of a purchased square, and because they’re made from wood, they will not scratch the wood pieces being squared.
I thought I’d take advantage of this article as everytime I watch one of Rob Roziaeski’s podcasts I get square envy as he uses Roubo squares in several sizes and I just like the looks of them. The more I use tools made from wood the more I want to use them so I see a fair amount of tool-making in my future.
Materials
I looked at what materials I had in the scrap box and came up with some hard maple, some cherry, and some red oak. I cut enough pieces to make half a dozen squares, though I really don’t need that many. The key, it seems to me, is that you must ensure that the faces and edges of each piece are flat and square to each other.
I’m fairly confident that maple and cherry will make good squares but I included the red oak as an experiment. Red oak is known to move quite a bit which is not an attribute you want in measuring devices. Time will tell whether this is a problem or not.
Making a Bridle Joint
The squares are pretty simple, involving a 1/4″ thick blade and a 3/4″ thick handle. They are connected to one another with a bridle joint, which I pinned with a couple 1/4″ dowels.
Laying out a bridle joint is easy as the blade width determines the depth and the blade thickness the distance between the two saw cuts. If there’s a “trick” to bridle joints it is to have practiced sufficiently with your saw to cut square and true. I used my dovetail saw to make the two cuts in each of the handle pieces. And I only screwed up one of them.
Some might wonder why I don’t use a tenon jig and run the handles through my table saw rather than do this slot chopping. Truth is, it simply takes too long to set things up. Doing it by hand is really fast as the two photos above indicate. You simply hit downward on your chisel vertically. Then, coming in from the end with the chisel and you can remove 1/4 of the material that needs to be removed. I repeat this twice more, and then flip the stick so I can access the other side. When I hit the piece with vertical chisel blow the last fourth pops out. If you’ve made your cuts correctly, you’re done.
Glue the Joint
Obviously, if you’re going to rely upon a square to check square, it must be itself. Thus, it is imperative that you glue the bridle joint absolutely square. I use hide glue for this, knowing that I can easily undo the joint with steam if the result isn’t square. Once glued, I left the squares overnight to completely set and rechecked them again before pinning the joints.
Pinning the Joint
I’m sure there are various opinions about how to determine where to put the pins. I simply laid a straight edge between the inside and outside corner and measured in 5/16″ from each corner. This looked “right” to me. I drilled 1/4″ holes through the joint and used a wooden mallet to pound cherry dowels through the joint. I used a flush cut saw to trim the dowels on each side of the joint.
One piece of advice for those who don’t own a flush-cut saw and want to buy one. Avoid the Stanley saw. Flush-cut saws should have no tooth set on the side of the blade that is flush with the surface. The Stanley has set on both sides of its blade and it’ll scratch up your piece every time. I use the saw from Lee Valley and it works great and costs only a few bucks more than the Stanley saw.
Making Them Fancy
At this point the squares will work just fine but they aren’t yet “kewl.” I drew out some guidelines for cutting trim on the ends of each piece and then us my scroll saw (fret saw will suffice) to cut the decorative trim. Absolute accuracy is less important than cutting smooth curves and square corners. It’s ok to make happy sounds as you finish up this step.
Final Form
All I did to finish my squares was to give them a dose of boiled linseed oil. I’d given the wood a couple swipes with a smooth plane before I started joining blade to handle and so no sanding was done. Notice how I assembled one of the maple squares backwards. Without screw ups, how else can one appreciate when things go well?
Cheers — Larry
Q&A: Why Do You Use Those Crappy Clamps?
One of the problems with discussing woodworking in blog posts is that we tend to concentrate on a single aspect, discussing it in isolation from all other parts of woodworking methods and choices. This will be an exception in that I can’t answer a question about clamp choice without discussing other choices I’ve made.
On several occasions, when I’ve pictured my ratchet clamps in use, people have written and asked “Why do you use those crappy clamps?“ I chose that way of depicting the question as it was less inflammatory than some other ways the question has been asked. To those who were simply rude and justifying to themselves why they’d spent $500 on a rack full of Bessey K-bodies, [sound of a raspberry being blown here]. To those who genuinely wanted to know why (if?) one should use ratchet clamps, what follows is my reasoning and the reasons why I can/do use these clamps often.
1) They’re cheap.
There is no doubt that if you decide that you need to equip your shop with a bunch of modern “K-block” clamps, you’re going to spend a bundle on them. If money is no object, they do look nice when hanging in a wall shelf and they undoubtedly do a fine job of squishing joinery together. Push-button ratchet clamps on the other hand are cheap, particularly the smaller ones.
2) They’re handy in my shop.
This is a situation unique to my shop but others could do the same thing. Right above my work area is a small wood rack. To it are attached all my ratchet clamps. When I need them I can reach up, push the button on a clamp and it’s in my hand and ready to use. Maybe it’s cuz I’m lazy but not having to get the clamps before I start a glue up works for me.
3) Because of the way I work, I don’t need lots of clamping pressure.
Here’s the important stuff. Here is also where clamp usage and other woodworking decisions converge and where the discussion becomes more diffused. Because of the things I do prior to glue ups, and the glues that I use, I simply don’t need as much clamping pressure as many seem to think they need in their work. In my opinion, if you need a lot of pressure to pull a joint together, the joint is ill-fit but I’m not here to preach. Here are a couple of the factors that allow me to achieve tight joinery without a lot of clamping pressure.
a) Prep the joinery by hand
Power tools are great for a lot of things but it you want tight joinery, hand tools bring much to the table, presuming you’ve practiced enough use them. On this last limitation, I am still a work in progress and must defer to many others who are my superior when it comes to hand tool use. Still, I can create joints that have no gaps between the two parts being joined.
With hand tools, there are things one can do to eliminate glue-up problems. For instance, if you match-plane the edges of two boards you’re going to glue up, the two boards will fit together so well that clamps are not needed to pull the joint together (see below). For those unfamiliar with match-planing this amounts to jointing the edges with the two boards clamped together. You use a jointer plane in the same way you would for one board but by doing the two boards simultaneously you will achieve a perfect match of the two boards as they come together. Similarly, fitting tenons to a mortise can be done .001″ at a time with the use of hand planes.
b) Glue choice – the most important parameter
Beyond working with hand tools, however, much less clamping is required if one shuns slippery, aliphatic resin glues in favor of hide glue as your primary glue. Aliphatic resins replaced hide glues in production shops because 1) they are far cheaper, 2) require less maintenance when used in volume, and 3) clamping is less of a problem in a shop that using fixtures to clamp pieces on a production line. But these glues bring to the cabinetmaker, creating pieces one at a time, are glue joints that will slip, creep, and where the glue does not hold the joint together and so joints must be clamped and clamped tightly.
By contrast, hide glue is a very tacky substance that is not slippery and actually pulls the joint together as it sets. And hot hide glue will hold a joint in place almost immediately as when the glue temperature 20-30C, it will sets, holding the joint together. While complete setting of the glue requires several hours just like aliphatic resins, you don’t have to hold the joint in place while that happens.
If you’ve heard about “rub joints”, once commonly used by cabinetmakers, this is why they work. You simply slap hide glue on two parts, rub them together and walk away with no clamps whatever. To see good examples of this I urge you to check out podcasts by Rob Roziaeski over at the Logan Cabinet Shoppe. Podcast #17 (attached knee blocks without clamps) and Podcast #18 (does a panel glue up without clamps). If all you’ve ever used are yellow glues, you have to see the process to believe it.
And so, while “cheap” and “convenient” are part of the answer to why I can and do use ratchet clamps, the real reason is that I “can” because of the methods I use. More and more people are embracing hide glue, realizing its virtues. If you’d like to investigate it, you might start with some of my earlier posts on hide glue:
Stephen Shepherd’s Hide Glue Book
Are there times when I need more clamping pressure? Sure. If I were laminating a bunch of 2x4s together to create a bench top I’d drag out my pipe clamps, my F-body clamps, and I wouldn’t have enough of them. But for most things I don’t need any more pressure than those “crappy clamps” provide me.
Cheers — Larry
Keeping the Hide Glue Warm at Wood'n Bits
Anyone who has followed this blog knows that I’m a fan of hide glue. I like the fact that it is stickier than PVA glues and thus the pieces I’m gluing don’t slide around while I’m clamping. More important, though, is that it can be debonded with heat and moisture, making repairs easier. It’s easy to fix glue up mistakes too, mistakes I never make, of course.
And while I use both liquid and hot hide glue, I find that hot hide glue is superior. Rather than reiterating all my thoughts on hide glue, here are two posts I’ve made on the subject:
Today, though, I want to talk about a new pot for heating my hide glue. If you follow the links you’ll see the pot I’ve been using. It’s a thermostatically-controlled tea kettle and I’ve used it as a double-boiler, keeping the actual glue in a container sitting in a water bath. This works well but suffers from the fact that it heats so quickly that it overshoots its temperature setting. I also, sometimes, get water slopping onto my bench but that’s cuz I’m like a whirling dervish when I’m doing a glue up.
I heard about this pot in a Twitter discussion and while I wish I could remember who recommended it, I can’t remember who gave up the name “La Grande Wax Warmer.“ It’s used to heat various torture devices sold under the auspices of removing body hair. Ya just gotta love any product that requires two languages to name it but I guess if you’re selling stuff to people who think sticking hot wax on themselves and then ripping it off is ok, this makes sense. There is also a smaller version called “La Petite Wax Warmer.” In fact, I ordered the small one. I paid the price of the small one. But they sent me the larger one. Go figure but I’m grateful for the error.
In spite of its true “raison d’etre”, this device has two attributes that I really like in my tools. It works very well and it was dirt cheap. The first thing I wanted to see was how long it would take to heat and, initially, I was disappointed.
It takes about 15 minutes to take cold water and heat it to hide glue temperature. I tested it with cold water because I often have hide glue in the fridge and so I figured the cold water would be a close enough mimic. My initial disappointment turned to joy, though, as the slower heating brings the contents to temperature and stops – the temperature control of this device is wonderful. With my old system the temp would heat to around 170F and then drop back to the 150-155F that I like. Then it would cool a bit more and the cycle would repeat. This device does lose a couple degrees when I remove the lid but not much and there is no over-heating. My preferred temp comes at a setting just about half of the max setting.
I don’t normally store my glue in the pot but I might start, at least for short periods as the lid on this pot can be locked in place and the seal is quite good. In operation you just set the lid on top of the container. I’m a happy camper and my shop is just a wee bit warmer.
Cheers — Larry
Fish Glue – a Sticky Solution
I’ve talked about how I use hide glue when building miniature furniture and I’ve discussed the reasons why it is superior to the typical yellow or white glues most use. More recently I’ve talked about Stephen Shepherd’s new book that is a complete treatise on all aspects of animal (hide) glues.
I hope this helped at least a few to learn and experience the virtues of this time-honored glue. Today, though, I’m here to discuss what this discussion has done for me, the author of those posts. Feedback is the best part of a blog and Peter Tucker, a true master miniaturist, wrote to me about hide glue and he mentioned that he was using fish glue in his work and that he liked it.
Being a glue junkie I ordered a bottle from Lee Valley. Fish glue is really a variation on hide glue. All of the animal glues, whether they be hide glue, fish glue, rabbit glue use collagen as their base so in the case of fish glue, fish collagen is used to produce it. Fish glue isn’t quite as strong as hide glue but in miniatures this difference isn’t important.
Lee Valley’s fish glue, however, is sold as a liquid, with urea added to it to keep it liquid at room temperature. There’s no need to heat it as I describe in my hide glue posts. I could also suggest that you ‘don’t get to heat it’ but only those who have actually used hot hide glue would understand what I was saying.
You can buy liquid hide glue as well, of course. In my experience, however, it’s not quite as nice to use. Liquid fish glue, however, has the virtue of being VERY sticky. You can apply it, stick two pieces together, and in most cases, they will stay stuck so you don’t need clamps of any kind. This, to me, is the virtue of hot hide glue as when it cools it will hold things in place as the glue sets.
If there’s a downside to hot hide glue it comes when you have a complex (many parts) glue up as you have a very short time to work as the glue cools quickly. This is a great time to haul out the fish glue. My fish glue “technique(s)” are simple. They are:
1) Use a small applicator bottle. Here’s my bottle.
They’re available from Williamson Walton Marble. You can squirt out the glue just like you would yellow glue except that it’s thinner and so easier to get it through a small tube. It’s also the case that if the nozzle gets plugged, all you need do is put it under hot water and it will clear out.
2) I use micro-applicators to spread the glue. These are too pricey to use with yellow glue as you can’t get them clean. With hide/fish glues, however, hot water will clean them out squeeky clean and so you don’t need to throw them away after use.
The green ones are larger than the white ones so I just choose the one that fits the joinery best.
Once you apply glue and stick the parts together the glue will generally hold them in alignment. The photo below shows two parts right after I’ve stuck them together. The joint needs no clamps, though being the guy that I am I’d generally use some anyway to pull the joint closed.
The downside? Unlike hide glue crystals, that will sit on a shelf forever, liquid hide/fish glues have finite shelf lives, just like yellow and white glues do. With that in mind I still recommend you add this glue to your arsenal.
Cheers — Larry
Stephen Shepherd's Hide Glue Book
You know it’s a good day when a book arrives in the mail. Today is a good day as I just received Stephen Shepherd’s new Hide Glue: Historical and Practical Applications book. If you’re not familiar with Stephen, he is a consummate craftsman and shares his knowledge via his Full Chisel Blog. His long awaited hide glue book is now available from Tools for Working Wood and I can’t recommend it enough. He writes in a friendly, though succinct style that make his books fun to read and yet the information density is high. This 133 page book is packed with historical and use information and the illustrations are a joy to behold.
What is hide glue, you ask? Well, it’s the glue that’s held things together for most of human existence. It’s the glue used by the craftsmen who created all the great antique furniture that we miniaturists drool over in the antique stores. It’s also a glue that has been replaced by modern “carpenters glues” not because they are superior nature but rather because they’re cheaper to produce. And if you’re using thousands of gallons of glue on the Ikea furniture production line, maybe that matters, but for most of us, the virtues of hide glue are well worth the few cents a year extra you’d have to spend to use hide glue.
Shouldn’t we be choosing our materials based upon criteria other than cost? Instrument makers and those doing veneering regularly have never abandoned the use of hide glues. What do they know that you don’t? Stephen’s book will yield up all of the answers.
While I don’t scratch the surface of the material in Stephen’s book, I did make the case for using hide glue in miniatures in two previous blog posts titled “Hide Glue use for Miniature Woodworking – Part 1” and “Hide Glue use in Miniatures – Part 2“. I encourage you to read those posts and then order a copy of Stephen’s book. You’ll be glad you did.
Cheers — Larry
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