Long straight dado?

[Jonathan W.]

I am finishing up rebuilding a barn/shed on family property to make a small apartment.

The original first floor (about 25 years old now) was 2x6 tongue and groove, laid over 4x6 on about 3 foot centers. I had planned to sand the wood floor and put several coats of poly on it. The wood has some character and will look OK.

This building is on the shore, and was knocked off its pilings a few years ago. I jacked it back into place and bolted it more thoroughly down.

My problem is where the edges of the 2x6 come together on the top (inside) there is a gap between most of the planks of between 1/16" and up to 5/16". I had originally thought about filling the cracks with epoxy and a filler, then decided it would look like shit. I've tried cutting tapered splines to drive in the cracks, but some of them (cracks) vary so much in width over a 14' run, that I am afraid of not having enough embedment to be leaving wood in the crack after sanding the floor.

I thought of routing the worst of them out to say 1/2" wide by 1/2" deep and laying a spline of a different color wood (I have a lot of Australian Hard Cypress left over from another job, and the upstairs of this one). I thought that would give an effect sort of like a teak and holly sole on a boat

I am not all that conversant with a router and the first test groove did not come out well. I tried cutting the 1/2" x 1/2" groove in one pass, with an Oldham Viper bit, the box mentioned starting from an exposed edge. I have an old Craftsman 6 amp router that says it is 25,000. rpm

From reading other posts, I see it might have been better to set my "fence" up on the left side of the groove, but what else do I need to do? If I have to make three passes with a different depth every time it obviously makes the job that much slower....

I had thought to run the bit down the center of the existing crack, thus taking some meat out of each side, but might the differing characteristic of the different planks affect the cut?

Are there Dado kits for skilsaws (7.25 circular handsaws)?

Any other ideas?

[Jay Pique]

WRT the gaps in the floorboards, I've seen various sizes of rope crammed down between them on TOH before.

I doubt that filler/adhesive would last. Perhaps you could reinstall the entire floor?

JP

[Duane Bozarth]

"Jonathan W." wrote: ...Please don't multipost---if you want to get more than one group involved, crosspost instead.

My suggestion elsewhere.

[Andy]

I've never heard of a dado set for a handheld circular saw, but I don't think a router would be that difficult. Yes, set up a fence (or clamp a straight 2x4, or whatever) exactly 3 inches to the left of where you want the middle of your dado to be, then just run the router along the fence. (Of course, if your router base is different than 3" in radius, adjust accordingly). Once at 1/4" depth, then at 1/2", would probably be fine. Once the fence is set up, it would only take about an extra minute to do a second pass. Good luck, Andy

[Charles Krug]

Sears sold a circular saw dado blade back in the '70s. I've never seen one nor spoken to anyone who ever used one.

I like a router for dados on large panels. It's easier to wrangle a five pound router than a forty pound panel.