At this point I decided to get more “radical” in my design approach. I removed two of the cross rails (found out through experience that I didn’t need them anyway). Then I took the corner poles out of the flanges and put a “sleeve” on the side of my table for the corner poles to slide into (see photo below). Electrical conduit clamps work great for attaching the sleeves.
This design also allowed me to adjust the height of the router sled in two ways:
1. The corner poles were now adjustable up and down by sliding them up and down in the sleeve. The stop collar you see in the photos just at table level can then be used to hold the corner pole securely in place.
2. Because the stop collars in my earlier designs were so hard to get positioned and secured properly, I decided I had to try something different for the rails the router sled rode on. That’s when it hit me that pipe clamps have a self locking base plate that would be perfect for this type of application. Voila! Why didn’t I think of this earlier? I still need to buy two more pipe clamps to put on the back two poles.
The beauty of this design is that now I have a method that allows me to easily move the cross rails up and down, plus it serves a “dual purpose” that gives me 48” pipe clamps when I need them, as well.
As you can see by the height of the two stumps shown in the photos, this jig allows planing of sizable pieces. In fact, any piece up to a height of 40” can be done with relative ease. I’ve done sofa and coffee table bases/pedestals with this jig with close to perfectly parallel tops and bottoms. I can hardly wait to try it on a lamp base, too!
The square in the photo below is what I use to measure where to set the pipe clamps to get them the same height on all four corners. I set the sled as close to the top of the piece I’m working on as I can, and then I micro adjust each corner using measurements on the square to get it close to perfect.
The trick for getting the top and bottom of the piece(s) parallel is to shim them prior to the first planing effort in order to get everything as straight as possible and to minimize the amount needing to be planed off (see photo below). Cardboard pieces, thin plastic, or other suitable material works well as shims.
Once the piece is shimmed, the procedure is simple:
1. For these two stumps I had to fasten them to each other because they were intended to become the legs for a simple bench I was making and these legs had to be exactly the same height. As you can see in the photo below, I fastened them together by lag screwing a 2×4 onto each stump to help prevent movement.
2. The next step is to secure the piece to the table (I use ratchet tie downs most of the time, but I’ve also used bungees which are not as secure). In the photo below, I used only one tie down, but I would advise using two most of the time for this type of work, if possible.
3. Once the top is planed down evenly, it is a simple matter to flip the piece over (it won’t even need to be shimmed for this next step), remove the 2×4 and refasten it at the bottom as before, secure the piece using the tie down(s) as before, and plane away. The result looks like this:
Here’s a photo of the rough bench prior to finishing.
Next up – Version 2.0 (for the really BIG pieces!)