How to make a Bevel Lap Splice joint, for connecting a portable floor?

Question

I'm new to woodworking, and I've read that I could potentially create this joint using a table saw, jointer, or even a circular saw - but I do not want to rent/purchase one and find out that I can't.

Here is what it looks like / description:

Bevel lap splice joint The bevel lap is a variation of the half-lap in which the cheeks of the opposing members are cut at an angle of 5 to 10 degrees, sloping back away from the end of the member, so that some resistance to tension is introduced. This helps to prevent the members from being pulled apart.

I will be making floor panels that will hook together using this joint, and can easily be picked back up and stored.

Answer 1

This will be a tricky joint, and it won't be as strong as you'd like, because the 'neck' of the bevel will be pretty thin. But I'm going to explain how to do it.

You need a table saw and a jig/sled to hold your board vertically. This jig is usually used to make the 'cheek' cuts on tenons, so you may have one.

You'll make two cuts--one shallow crosscut at the deepest point of the bevel, and one face cut to make the bevel itself. Then you can optionally clean up the junction, or, you cut the notch a little deeper (at the expense of weakening the wood further); I show the latter (faster) solution here, since you'll be doing a LOT of these.

1. Carefully set the depth of the cross-cut to the depth of the bevel. (See picture two.) Cut a notch across the bottom of the wood.

2. Mount the piece of wood vertically in your cheek-cutting sled. Set the angle of your table saw to the angle of the bevel, looks like about 5-8 degrees might be enough. Adjust the left-right position of the sled so that the top of the cut lines up with the corner of the bevel. (See picture three.)

I have totally exaggerated the amount of kerf and overcut you'll get just so you can see the dangers. In practice you can make the second cut so that it doesn't overcut at all.

The annoying part is you can't test the fit until after step 2, which means you have to recreate the depth for step 1. Not the end of the world, just take your time and sneak up on the depth from the 'shallow' direction.

Answer 2

I think your question is, "Should I go ahead and buy/rent these tools with the confidence that I am going to be able to successfully cut these joints?" My answer is, "No." I'm not at all new to woodworking, I've been working on various tablesaw/router/bandsaw projects for years. And cutting these joints on 3x4 pieces of MDF would be VERY difficult to do cleanly. Not impossible, but definitely advanced.

I suspect you'll end up needing a fairly involved jig for a tablesaw, or a special bit in larger router/shaper.

I advise you consider alternatives. Using 16" laminate floor squares comes to mind, but any sort of click-lock laminate is pretty fast/simple to install, and would make a great dance floor.

But I don't think the fancy cut on the mdf is going to work for you.

Answer 3

OK, now that I know what your goal is, here are some comments:

A portable dance floor needs to have the individual sections lock together to avoid separation or movement and potentially resulting in injury and lawsuits. The outside perimeter needs to have a beveled edge to avoid tripping.

Something like the tabled lap joint would probably work best. This type of joint can easily be done on a table saw with an adjustable dado blade. The corner pieces and outside perimeter pieces will have 2 or 3 sides jointed, respectfully. The center of the field will have to have oriented splices on all four sides. The panels should be numbered for easy assembly.

As far as the material to use. MDF will glue up OK for vinyl, but since there will be thin edges at the splices, it could be very prone to corner and edge chipping if assembled/disassembled often. I might recommend an A/C marine grade plywood. It is very stable, strong and uses a moisture resistant adhesive between the plies. Vinyl will adhere well on the A side. It also will hold up well to moisture and spills. There will not be a substantial difference in weight.

Although this would not be a difficult project, some experience using a table saw with a dado on larger pieces would be helpful. Proper support for the stock while doing these cuts is important. The plywood stock needs to be flat and supported at all times for the dado cuts to be accurate, avoid kickbacks and assure your safety. Good Luck.