Many years ago I said that if you want to impress another woodworker, make a dovetail joint ... if you want to impress everyone else you can make box joints, and that is still true today. Most people cannot tell the difference and to an untrained eye, box joints and dovetail joints look pretty much the same, but box joints are much easier to make, and using a router means you can make very fine joints.
Watch it on Youtube: https://youtu.be/EzjG4bSrako
I first made this jig as a concept, I wanted to see if the same Lynn Sabin plans that created this jig well over 20 years ago, could be adapted to the router table. And it worked ... and it worked well. That jig I make many years ago worked fine so I didn't bother to make another ... until recently when I dug it out and found that some of the MDF and plywood that I used years ago, had cracked and the jig worked, but not smoothly.
So I thought it was time to make a much better-crafted jig this time, and with a few improvements that I knew of.
You can go and look at that first version I had, and you will find some other interesting things in the article ... it's HERE
Since the passing away of Lee Styron a few years ago, which is where the original plans from Lynn Sabin were kept, but when the site was re-made those plans were not part of it so I took it upon myself to offer them here on woodworkweb .. for free, just like Lee had done and you can download the original Lynn Sabin Plans here https://www.woodworkweb.com/free-woodworking-plans/func-startdown/743/
I will be using better grade plywood for the parts and where ever possible, I will use dowels for the assembly to make sure I get the strongest and most accurate build I can get.
I started off by cutting all the components, and then for the 2 sides of the carcass and for the carriage, I drilled identical holes through all of them at once so the redi-rod would be able to slide through all of them easily ... and it did just that.
Next, I affixed the plastic miter blank material to the underside of the jig base. This would be the guide as you push the jig and through the spinning router bit, that would keep the jig aligned on the wood router table.
Then I went about building the carriage, and this time I used 5/16 dowels. They really made a difference to alignment and assemble. The carriage came together perfectly square and super rigid.
At this point, it was time to disassemble the old jig to salvage the redi-rod, the crank, and the T-nut and keeper that I would use on the new jig. It does take a bit of fiddling around to get all the pieces of the redi-rod together, aligned, and set up, but the new construction really made it fun to do because everything aligned so well.
One of the issues that happened on occasion with the old jig, sometimes when you advanced the wood by turning the crank, wood sometimes caught in the slot on the base of the jig. When this happened, as you advanced the wood, all the happened was that the wood that caught, instead of sliding nicely, began to tip in the jig, which of course made bad cuts and I would have to abandon the cut ... re-trim the wood a bit smaller and start over again.
This time I did 2 things to help prevent this from happening, first of all, I sanded the edges of the slot where the router bit rides, to make sure the edges were smooth and easy flowing and the second thing I did was to make veneer strip with an easy pull-out handle that I can set the wood on in the initial alignment, the pull the veneer out before cutting. What this does is slightly elevate the wood so that it won't get caught in the router bit slot ... and it works better than I expected.
I also put 4, instead of 2, hanger bolts on the front of the carriage to hole the wood that is being cut, I just thought that this was an easy thing to make and purposeful make.
After a couple of days, I finally had the new jig finished and I was anxious to try it out. I started off with some test pieces, set them into the jig, and used the veneer to elevate and, slightly re-set the bit height a tiny bit higher, aligned my pieces in the jig, and began cutting them. I was amazed at how smooth and easy to use the new jig was. I set up stops on the router table so as not to waste my time going to fare in or out, and the first set of box joints came out perfectly.
At that point, I knew the new jig was done, all I had to do now was to make a second set and videotape the working process ...
Copyright Colin Knecht
woodworkweb.com