Adding Bracket to New Transom

[billfisher]

After raising the transom from 25 to 30 inches, I decided to do this??? I used Coosa 26 for the engine box, two layers of 3/4" with two layers of 1708 mat in and out of each layer. The float pods on each side are 1" corecell with the same glass and then filled with two part foam. I estimate the whole thing weighs about 100 to 110 pounds. I hope it workes out. Set back is now 25 inches from the original transom, but I am also adding a CMC 5.5 inch set back hydraulic jackplate for running in skinny water. Any thoughts or comments would be appricated.

[Bryan A.]

Interesting.

I can't tell from the pictures but does the platform created by the "pods" line up with the existing waterline?
Are you going to fill in the notch?
Looks like it will work from here. Interesting bracket.

[FELLOW-SHIP]

Ha Lou;

First off on the first picture your transom looks just like me old transom when I did my boat. I had so many holes in it that it looked like it was used for target practice by a mini machine gun.

As to the bracket how is it attached to the transom?
Is any of it attached to the stringers in side the boat?
Is there any part of your bracket through bolted through your new transom?
Or is it simply attached to the outside skin on the transom? I can’t tell with the pictures.



FellowShip

_______________________________________________

My motto: Just for the Grins

[billfisher]

Platform height? It is even with my old boot stripe, about 3" above my old water line, so I hope it will be at or about the same height with the added bouyancy I hope to pickup? As far as attaching to the hull? It has overlapping layers of 1708 mat from both directions of all structual foam pieces that come into contact with the hull, sides bottom and both layers of Coosa26. I would say that the total laid up thickness of the glass is between 1/4" to 5/16" with each mew piece extending over the first onto new glass. The transom was beefed up using 3 pc's of 3/4" Okume ply glassed between each layer using the same 1708 mat. Also added large gussets to add stiffness to the new transom. As to the question, any bolts, No, hopefully my motor won't fall off??? Now U have me wondering if I should bolt the CMC bracket on and extend the bolts all the way thru the transom,??? See additional Pic's

[Bryan A.]

Fellowship brings up a good point. Without the bolts it seems you are relying on just the outer skin to hold the weight of the motor. I would say bolts with large plates or washers would be needed to tie the whole thing together. After all a transom is basically layers of wood or foam, glass, and resin. The outer skin being just that, a skin. I think Strick posted a while back about using plates and washers to secure his home made bracket.

[FELLOW-SHIP]

Ha Lou

What I see of your work you have done a great job and looks very very good.

I am no engineer and really don’t know how much stress that engine sitting on a bracket puts on the transom but “For Me” I would not trust a bracket that has just been laminated to the outer skin of a transom and expect it to hold. Maybe some one else who knows this type of stuff more then me will chime in on this point. I really like your idea & I have talked about fabrication a integrated bracket into the transom on two separate occasions but I have always thought that you would have to connect the stringers to the bracket and beef up the outside wall of the transom to at lease ½ to ¾ of a inch to boot. Kind of like how Sea Vee does their boats. If you don’t at least through bold through your transom the ¼” outer wall of the transom could de laminate from the transom core and you just lost your $15,000 motor. Again maybe some one else could talk about these types of issues.


FellowShip

_______________________________________________

My motto: Just for the Grins

[wavelength]

Are you going to fill in the notch?

My question also

[billfisher]

Oh yeah, the notch??? I haven't decided on what I'm going to do there yet. I have thought about going up half way to create a seat/cooler combo type of thing, but I like the easy access to the platform as I plan on using her in and around the barrier islands of the Eastern Shore of Virginia. We can get on and off easier than climbing over a full transom. Just not sure how thats going to pan out yet? Thanks for all the quick response's. I think I will have some custom stainless steel threaded rods made up next door and take the advice of the powers that be here, and lock that whole mess down by extending the bolts all the way thru the transom. I was leaning that way, but wanted to limit my holes in that new transome. The votes are already in, THRU BOLT IT!!!

[Old'sCool]

You might also consider a real sea-cock thru hull valve. Nice work!!

[Bryan A.]

Are you thinking of running the bolts from the motor all the way through the bracket then into the transom with one continous rod? If so you may want to make up a sleeve for the inside part so it does not "squish" the whole bracket. Or maybe just nuts and washers on the inside between the transom and bracket and the motor and the bracket. Just a thought.
Nice work so far. Can't wait to see it in the water.