Sawhorses are indispensable for a normal household or a shop. You can use them for painting, work piece support, work bench support with a piece of plywood or door, and with a little imagination, they can be used in many other different ways like magic. The folding sawhorses are particularly valuable, as they can be stored with very minimum space, carried in your vehicle, and set up quickly when you need them.
There are many ways to make folding sawhorses, and it’s not the intention to claim that this is the best way, it's just my way of doing it. If somehow there’s a design details that has been seeing somewhere else, that means either the design was inspired by the other fellow designer's creative mind, which is really appreciated, or all good engineers follow the same physics & design principle - simple, functional, most efficient in strength and maximize material usage. I am sure there are some rooms for improvement for this project, please comment with your idea, and we’ll make it better – will try to make another pair in the near future if necessary.
One more thing to take consideration, the sawhorses were not tested to see how much weight that they can hold up, except I only jumped up and down on one of them with my 175lb body, so they can probably hold at least 200lb each without a problem.
Step 1: Materials
I started with some leftover 1x6 (5.5” x 3/4”) from here and there for the legs, and one piece deck board as beams (treated 5.5" x 1") but didn't have enough for 4 beams, so I replaced one of them with just a 1x6. An 8' 1x6 will yield 3 leg pieces with almost nothing to spare if the the final height stays at 29". Using 1x6 because it’s fairly light and reasonably wide, that will give a chance not to use stretchers at the bottom.
The leg pieces are 31 1/8" long to get 29" of sawhorse finish height, based on the calculation that I will show in next page. The regular sawhorses are 30" high, a few reasons to not go for 30”,
We as regular person normally get 8' boards from the home center, they are 96". If we want to have 30" sawhorse height, then the leg stock would be a little over 32" long, with miter and bevel cut on the boards for this application, we will not get 3 leg pieces out of one 8’ board, our goal here is trying to use up the board and create minimum waste.
In case you do need 30" height or more, you can always add another piece (which will also become the sacrificial piece that you can cut into and replace when it's in bad shape), or even a 6" to 8" high torsion box on the top to make the dimension you would like, and make it the torsion box work table if you need. I built a couple of sawhorse extensions for use of my table saw out feed table set up, click the link if you are interested to see a way to increase the sawhorse height without making another set.
Picture is showing the sawhorses been used in my other project, holding a bunch of 2x materials for part of my basement storage shelf units.
Step 2: Design and Math
Here are the design and the related simple math on a couple of papers before I build them.
I am an engineer, in most cases, I would do this in my head, but decided to draw them out this time, because these sawhorses are just part of the whole portable table project. I would like to keep the record of what I did, otherwise, the forty-some-year-old brain of mine kind’a likes to forget things. Here is the proof, I just realized that on the first picture, I wrote the height of the sawhorse as 30" in two places at the bottom, which were mistakes, I think I was struggling to decide whether build them at 29" or 30" in height, and messed them up at the drawing, before I made the decision for cutting down to 29” finish height to use up an 8’ board.
Step 3: Cutting Away
All 8 legs were cut with 15 degree miter and 15 degree bevel. I used compound miter saw. Measure once, cut 8 times with a stop at one side. The trick here is not cut everything in accuracy to 0.001” but to repeat one fairly good measurement 8 times so that all the pieces are the same length. The orientation of the board should be cut the same way, we will get to that in the assembly process.
4 beams are all cut with 15 degree miter only, but have the bevel cut at the shorter side along the whole length. I use table saw with blade tiit 15 degree, and put longer side against the fence. Make sure cut them at one set up without move the fence. Again, we are looking for repeatability with reasonable accuracy.
Step 4: Assembly
Assembly should be easy and painless if all the parts were cut right. Again, try everything you could to be consistent.
There are 8 joints total in this pair of sawhorses, the way to join them is the same. Dry fit one beam and two leg pieces (one on each side) together on a flat surface. I put a couple of cut off pieces from the beam under the leg pieces at the other end as spacers to ensure the assembly sits flat. My beams are 1" thick, and legs are 3/4" thick, I decided to put screws through the leg onto the beam so I can have more bite material.
After figuring out the orientation of each parts in the dry fit (a little tricky because the legs spread out in different direction), use glue on both part and screw them together. Remember, glue is like a lubricant when wet, I would put a couple of small nails after all edges aligned to lock two parts together before screw them so that they don't move out the alignment. The picture will show three little brad nails - two by the knot and one by right bottom corner screw.
I left the assembly set over night before I put hinges on, but you can do it right after the joints are completed. I used gate hinges because of the length of each side, I think they are better than door hinges in this application. The hinges were sticking out the top surface a little, I didn't bother to correct them, because I am planning on put another board on the top, I can use a router to cut a couple of shallow slots on the bottom of the board to get it sit flush
Finally, I use some leftover chain to ensure the two folding pieces will not spread apart too much under the load. It's just two 1 5/8" screws one on each side. (use longer screw and pre-drill the holes). The way to attach the chain is, I measure 21" on my assembly table, put two screws at each end, spread two sawhorse legs to that two screws, and attach the chain. I did 21" because of the following rough calculation: 8"+8"+5x1"=21" (refer to step2, W+W+5x thickness of the material at 15 degree).
Rick Habecker made it!