Crossbeam fit and padding

[Scott Veirs]

Hey all,

Any opinions about what James and Hanneke mean by "loose fit" when describing how to build the beam sockets and blocks in the Tiki 21 crossbeam plan.  Sheet 12 says "Beam should be loose fit to allow for paint and wood expansion."  Are we talking 1mm here, or 5, or 10?

Also, any recommendations for the padding that lines the sockets and covers the pads?  Plans call for 3mm thick "rubber."  Any common (re-used?) source folks like?  I've heard that a lot of beams squeak quite a bit at the contact points.  Is that happening in the sockets and on the pads, or where the beams rest against the cabin?

Thanks from Seattle,
Scott

[kim whitmyre]

McMaster Carr: they have everything and they ship fast. Once you learn their website, you can find what you need quickly. As for the fit, you don't want to have to pound the beam on. . .;~)

[Scott Veirs]

I'm getting the fit down to 1-5 mm with the lashings tightened down on the rubber pads. (We're trying some 3-4mm thick red rubber from local hardware store for now.) The fitting can get pretty involved given all the odd angles, both horizontal due to the along-deck curvature and vertical due to the across-deck curvature.

[Scott Veirs]

CROSSBEAM BLOCK CLEARANCE PROBLEM

A separate, more serious issue arose recently when lashing the beams on. The beam blocks we glued/screwed to the bottom of the beams are contacting the deck before the beam contacts the outboard beam pad/sockets. Even rolling the hulls can't resolve the problem as the gap between socket top and beam bottom is 1-3 cm. It's as if Hanneke and James forgot to add a second layer to the outboard beam pads, or we didn't get enough curvature in the outer ends of our beams, or the decks are bowed upward too much.

Have any other Tiki (21?) builders had this issue arise?

Ideas for solutions?

I'm leaning towards just adding another 1x2 layer to the outboard beam pads. An alternative might be to sand down the beam blocks where they contact the decks, but in some cases that's not going to leave much block!

Cheers,
Scott

[kim whitmyre]

Scott,

For clarification, here is a shot of my new aft beam pads fitted some months back:

The inner pad, as you can see, has a portion that sits proud: this fits into a "socket" on the beam underside. You can just see this socket on the beam directly aft of the pad. My socket is flush with the bottom of the beam. . .Are you saying (in my terms) that your socket is proud of the beam?

[kim whitmyre]

Scott,

This is what I did in fitting the blocks on the hulls: I laid the beam in position on the hulls, center of hull and beam touching, and measured the space between the hull and the pad locations. Then I added a 1/4"/6mm to the measured distance. This insured that the hull/beam center between the pads would have that much clearance.