Domino Deck Rail Miter Repair

[nycneal]

Greetings All!

I’m hoping you can provide some wood movement/wood repair guidance.

(Apologies if this has been asked and answered before.)

The miter on this Chicago deck rail has opened up. I can certainly domino it back to together, but I’m wondering if the seasonal wood movement will find someplace else to split once the miter is solid.

Also, any tips on domino settings, size, etc., would be most gratefully appreciated. For example, which domino settings would be most effective, loose fit, tight fit or a combination? (Sedge and Norm put one of each into a frame miter.)

Thank you!

Neal

 

[smorgasbord]

The miter on this Chicago deck rail has opened up. I can certainly domino it back to together, but I’m wondering if the seasonal wood movement will find someplace else to split once the miter is solid.

Yeah, miters on outdoors wood with a clear finish are gonna gap at one end or the other as the boards get wider and then narrower. You can domino on the inside corner, but for the outside you might try something metal - but ultimately I think it's gonna fail.

I'd redesign the corner to use a butt joint. It won't stay flush, but that won't be as unattractive as a uneven gapped miter.

 

[mcfal12]

An another suggestion- depending how difficult getting the rail off is - would be to use pocket holes (from the underside) and outdoor wood glue. It might have more holding power than just a domino. I will caution- as pointed out - future wood movement might then result in a split at the joint or on the other end.

Or, attach the short miter with glue and let if ‘float’ over the post reducing the stress in the joint. Some type of ‘z’ faster might allow for some movement. The challenge- as best as I can tell from the picture- is that appears to be at the top of the steps and someone may pull on the rail or use it as a hand railing when using the stairs.

 

[SoonerFan]

I have a DF700 and would probably use a couple of 140mm tenons to provide lots of surface for glue. Then I would either use pocket screws from underneath as has been suggested or add a couple longer GRKs and plug the holes. In Chicago with the humidity changes the miter could continue to separate no matter what approach you settle on. Good luck and let us know how it goes.

 

[peter halle]

Miters on exterior wooden handrails are, to say the least an issue. That piece is going to expand and contract constantly due to moisture content and you aren;'t going to stop that. I remember one job I was on where the homeowner had "bad "miters on the top cap of a handrail. I replaced them and she commented on how perfect the joints were. Two days later I was the scourge of the earth after the wood - exposed to the sun - shrank and the joints opened up like before. I redid the railing one more time to prove to her that it was beyond my control, and a couple of days later I was proven right.

Good luck!

Peter