Bedding Transom

[kentjw]

I'm just about ready to install my new transom (white oak) into my very old Beetle Cat. I've plained and sanded to a pretty good fit but still have some small gaps because of the unevenness of the old cedar planking. The transom has a tappering bevel that has occupied the good part of two weeks trying to get just right. Of the three compounds I have on the shelf, 3m5200, Boat Life Life-Caulk (recommended by the builder) and Dolphinite bedding compound, I'd like to know which one you guys and gals think would be the best to bed the transom to the hull?

[Ted Chism]

I have recently started bedding cedar planking on to yew and white oak framing using a rubberized version of roof patch tar, and it seems to be working very well. Fairly easy to work with - skins over within a day, sticks like hell, dosen't bleed out, suposed to stay flexable, cleans up well with paint thinner when fresh. I plan to use it throughout.

[Hughman]

I'm just about ready to install my new transom (white oak) into my very old Beetle Cat. I've plained and sanded to a pretty good fit but still have some small gaps because of the unevenness of the old cedar planking.

If it were me, I would sort out this issue first, as it most likely will cause problems later. What it sounds like from your remarks is it seems you are trying to glue/stick/chemically fasten ragged planks - perhaps from a multitude of old fastener holes - to your new transom. The transom should be attached with screws, then caulked in a more traditional manner with a strand of cotton, then payed with seam compound.

This method allows for the inevitable movement of all the different parts with the likelihood of recovery, i.e. not producing new leaks.

To fix the plank ends, I've used Mr. Smith's CPES based coumpounds with some success - basicly an epoxy based putty and fairing coumpound. This allows new clean fastener holes to be placed where you need them to be, for a fair fit.

[kentjw]

I solved the tattered plank ends by first plugging all the old holes with an epoxy/woodflour mix and then added a transom frame as describe by Bill Blacklock on this forum. See picture. The transom is almost 3" thick where it meets the hull so I thought a good bedding compound would be in order - just can't decide which product to use.
http://s134.photobucket.com/albums/q97/kentjw/?action=view&current=transom002.jpg

[sdowney717]

I use a lot of PL Premium polyurethane construction adhesive lately so its at the top of my list for stuff like this.

I would simply glue it in and where you have gaps mix in some sawdust with the PL to cure it in thicker layers.

It wil not creep, it will still have some give because you wont be clamping it with a very tight fit.

It absolutely wont fall out or lose adhesion like 5200.

And it is very easy to use and waterproof suitable for underwater use.

If anyone had to take this apart later, it looks like you could pass a sawzall thru to separate the parts, SO it is not permanently attached like some might be thinking.

[sdowney717]

here someone used PL for strip planking,
Try it, and I bet you like it.

http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=67183&highlight=Premium