I thought this was pretty neat and cheap. This works like an Incra box joint jig.
Some of us are less fortunate than we who have an I-Box. Using any box joint jig will give blowout unless you have backer boards on the front and back using a router table.If you are going to make one box joint project and you are real careful it will work. I own an Incra I-Box and the presenter in the Youtube video is not even in the same ball park with the Incra. The Incra is so simple to set up and when I want to make a box joint all I have to do is set it on the saw table with my Frued 1/4" box blade and set the height and it is cutting time.
The presenter in the Youtube has to hold everything and hope it does not move.
As I said for a one of the jig is adequate but if you want to make multiple size (3/8, 1/4" or 1/8" inch) and set up and get perfect results then get an Incra I-Box jig.
There is no comparison between the two jigs other than they are both jigs.
Although the Youtube jig would work there are several things not said. The first one is you need a flat top cutting blade. An alternate tooth blade would not leave square bottoms on the finger cavities. The second thing is he should be using clamps to hold the work during cutting. What he does is very dangerous and I would not recommend you try his exact technique. Third his jig is relatively cheap to make but the Incra I-Box is only $150.00 and it can be used on the table saw or a router table. The Youtube jig can only be used on a table saw.
So to wrap up, if I want to make a 1/4" box joint I put the Incra I-Box on the table saw, set the 1/4" Frued Box blade to height and cut finger joints as long as I want, then the joint is repeatable and finished before this Youtube jig is even set up.
Won't say I am less fortunate, but I don't have one. On the other hand, I don't make box joints, and as of now, no plans to make any. I know if I ever do make some, I won't be making a lot of them, so it will definitely be homemade for me. Not necessarily this one, but one that works for me. No, I'm not cheap, just don't need one. However, if I ever did decide to make a lot of box joints, I kinda think I'd buy, rather than make. But, it's soo much more fun to make your own.Some of us are less fortunate than we who have an I-Box. Using any box joint jig will give blowout unless you have backer boards on the front and back using a router table.