I ordered the jig from Carl a few weeks ago. I had also ordered a new table saw, so I couldn't get the jig calibrated until I got the table saw fully set up and tinkered with properly (which was more difficult than originally anticipated). I finally got the jig put together and ready to go last weekend, cutting my first set of boxes last night. Here are some of my thoughts so far:
1. Some of the screws that need to be assembled, and of which are included in the kit, have square heads. I didn't have a screwdriver with a square head (only philips, flat head, and various hex wrenches). So I had to go purchase a new screwdriver, just to assemble the kit. I think it ended up being like $18 (for a screwdriver with about 20 different heads, the only one I could find that would work). Not a big deal, but a little bit inconvenient, as I doubt I'll ever use the square head screwdriver again.
2. Setting it up wasn't as easy as I thought it would be. It took some tinkering to get it all where it should be. The instructions were spot on, and I used the calibration board included with the kit to line the jig up nicely on the miter slots. Once set on the miter slots, it was difficult to secure the runners to the jig. Not a flaw in the design by any means, but it's a little difficult to look at something on the table and figure out how you are going to drill THROUGH the jig, THROUGH the runners, without moving the jig from the table (as if you move it, it may be off by a fraction of an inch). I got it all attached and ran it through the saw, but found out I was off by approx. 2 mm. I figured the runners wandered while installing, but when I double checked with the calibration board, it was spot on. So now I had to shift the runners 2 mm to the left, which wasn't too easy as holes were already drilled. So I had to drill some slots where the holes were so the runners could move from side to side, then get some larger washers to hold it in place, 2mm to the left. It all worked out in the end, but it took me some time.
3. I'm not certain, but I think the offset key is a little "off". I ran a set of boards through the saw with the offset key, and the box was shifted slightly higher on one board than the other. I flipped the joints over (to do the other end of the board) and this time used a scrap 1" piece of lumber instead of the offset key, and it lined up just right. I haven't taken the time to see whether it was human error on my part, or if the offset key is "off".
4. Personally, I think Carl needs to make a choice on whether this jig is for beekeepers or not. He told me that it is designed to be used for any type of box joint, not just for beekeepers. Which makes sense, except if you step back and think about who needs to make repetitive box joints. Jewelry box makers and beekeepers are the only two that come to mind easily. 3/4" or 1.5" box joints on a jewelry box are worthless, so I think this jig is really supposed to be used for beekeepers, at least my two cents. If that's the case, the dimensions of the box should be adjusted to fit beekeeping equipment only. Right now it's larger, to accommodate other size lumber. While I appreciate the versatility, I think it would perform a little better, and more consistent, if the dimensions of the sliding box fit two deep boxes exactly. Maybe I'm wrong though.
5. I had some difficulty with the clamp system. It's designed to house a pipe clamp on the right (through a hole), and a second to the left (lapped over the edge of the sliding box). The clamp on the right pulled the wood a little to the right when I secured it (could be my pipe clamp), and the one on the left couldn't go down far enough to stop the boards from separating a little at the bottom. I told Carl he should just put a second hole for the pipe clamp on the left where deep boxes go, a little further down. He reminded me that it wasn't just for deep boxes (or beekeeping boxes), which I think gets to my earlier point. When I had it running though, the pipe clamps went loose (the vibrations of the saw ended up loosening the clamps). It could have been with my clamps, but I ended up having some test boards become useless as they were moving around left, right, up and down in the box. I solved the problem by using two vice grip clamps.
6. I hear Carl talk about how versatile it is, but I don't see that. It's designed for a specific purpose: to make 3/4" and 1.5" box joints on one table saw. And it does that well in my opinion. But, because you calibrate it to the right blade of the dado set, and my arbor opens on the left on the table saw, if I moved to a 1/2" finger joint, or a 7/8" finger joint, I'd have to recalibrate the whole set, not just add/remove some blades/chippers and have some new flippers as Carl makes it seem. Which is just fine for me, as I don't foresee that I'll be making any 1/2" finger joints in my foreseeable future (or getting a new table saw).
7. As far as the 1.5" box joints goes, I don't see the advantage. Carl said many people like them because they require less nails for assembly, and hold the joint stronger. I disagree. It takes just as much time to cut on a table saw using this jig, so you don't save any time there. The strength of the joint has nothing to do with the face of the finger joints too. It has to do with how much side grain is secured to other side grain. In that respect, the more fingers you have the stronger the joint (all things considered equal). It's just not economical to make 1/8" fingers. You also don't have to put a nail in EVERY finger of a 3/4" box joint, if you don't want to. The nail doesn't do anything to the strength of the box, other than hold it in place long enough for the wood to dry. Two nails will usually hold it in place ok, but 5 or 6 would probably be where I'd limit it, adding in potential warpage.
In the end, I like the product. I would buy it again if I had to. I'd recommend it to others as well. But, I don't think I'd recommend it to a complete novice woodworker, and I wouldn't say that it's a "universal" jig, although when you initially set it up you can have it set for just about any size finger. Switching is the problem.
Well, there are my thoughts. Feel free to comment yourself if you'd like.