finishing bubinga

[agent511]

hi. I am brand new, working on my first project, a coffee table, made with glass and bubinga.

I need to cut large notches, about 2" wide and two inches high, into the middle of the bottom of the long ends.

I don't have a Dado blade, nor is my BTS15 table supposed to be able to use one.

I was thinking of standing the piece up - it is about 2 feet tall, 10" wide, 8/4 thickness, using the SMT and making the fence bigger with some clamped-on MDF, then clamping the piece to the extended fence, and just make many repeated passes, nibbling away till i get the full 2" width. Hopefully the construct will be stable enough.

Any better ideas?

Also what can I finish with - I was going to use Tung ioil, like they usuallyuse on DIY. But I see many people here use poly...

[Mainemarc]

Hi Agent511:

It's hard for me to picture exactly what you're trying to do with these notches; some sort of housed butt joints to accept a cross member of some sort?

If I'm picturing your desired milling operation correctly, and by fence you are referring to the miter fence on your BTS15, then yes, I think your proposal is a sound one. If you have a jig saw or a band saw, then you could rough out the opening with that and clean things up with the nibbling away operation you're proposing.

The two big gotchas in this operation are ensuring that your blade is truly at 90 degrees and the depth of cut is exactly 2". At the full 2" depth of cut, any minor error with the blade angle will be magnified. So don't trust the blade angle scale; double check with a square.

I applaud you for springing for quality wood like bubinga. I gotta admit when I was first starting out I cheaped out with pine and poplar and didn't come to appreciate beautiful (and expensive!) hardwoods until much later.

But I'd hate to see you ruin any of it. Test *everything* on scrap wood first. Even if you have to go out and buy the d**m poplar. The one truly useful thing I learned in my adult community education woodworking classes is that you want to test out every operation, every setting, every cut on scrap first so you have *absolutely no surprises* when you're cutting for real. Seems so obvious but that one little nugget will save you a tremendous amount of frustration (and expensive wood).

BTW, welcome to the forum!

[Ken Weaver]

I'd worry about the stability, especially on the BT15. I'd be tempted to put the long piece in a vise and nibble away with a circular saw for the 2" depth and then finish to the final width with chisels and patience. You're going to have a lot of clamps passing over an open blade with your set up. Take a look at the two tenoning jigs in the articles section. An extended design mod of those might work but you have to do more than just clamp a taller fence on it to get the stability you'll need. One uses the SMT the other slides on the rip fence. I'd be more comfortable with those designs rather than what you're suggesting. Even then, a 2' board that wide waving in the air would make me nervous.

BTW - welcome to the forum - enjoy and be safe!

PS - Trying to visualize things - if you are thinking of the 2x2 slots centered along the 2' length then the tenoning jigs won't do it. I agree with Marc if that's the case, I was thinking of the slots being in the middle of the 10" ends. Still, you might look at the articles to get an idea of how to fasten a stable fence extension to the miter fence. I don't think just clamping will do it.

[agent511]

Thanks for the good advice.

Yes, Mark, this is for a butt joint with a crossmember. Yes it is on the 10" side, not the two foot side.

Yes Ken, I like the idea of the tenoning jig in the article, esp the blackwalnut one that can be purchased. Still, I want to give this a shot with the clamps, and maybe get the jig down the line.

I will take the advice of experimenting first with other wood. I already had a heck of a time cutting dado grooves across the grain with the router, had LOTS of tearout. Then I clamped some scrap wood to each side, and that ended the tearout. ALso had to clamp on scrap to make a fence on each side of the router to eliminate any play. Made lots of mistakes, but I am learning.

On DIY network, they use sleds for all the crosscutting. Unfortunately, Ryobi doesn't provide the miter slots for a sled to ride on. The BTS15 has no slots at all. I don't understand why Ryobi is so out of touch with what should be a standard.

[Mainemarc]

quote:Originally posted by agent511

I don't understand why Ryobi is so out of touch with what should be a standard.

Well, the whole point of the sliding miter table (SMT) on the BTS15 and the BT3x00 is to obviate the need for many custom crossing-cutting sleds. I can't speak to BTS15, but the SMT on the BT3100 is inherently more accurate than a standard miter gauge for cross cuts.

About the only thing that everyone seems to agree on with regard to the BT3x00 series is that Ryobi essentially tossed out many traditional table saw design conventions (e.g. miter gauge, miter slot) and re-engineered the tablesaw to be more functional and accurate than most traditional designs.

The BTS15 traces part of it's lineage to the BT3x00, but it's more of a compromise design. Given it's compromises, I agree it would have been nice to have incorporated an integral miter slot for the BTS15.

But since you don't have one, concentrate on using the SMT to full advantage. And where you feel you absolutely need a specialized jig or sled, consider adapting the design to attach to your SMT.

There's a lot of good ideas and helpful people here who can help you out.