transom installation stuff

[beerrun]

Hi, so it looks like tomorrow night we are finally ready to put the transom in the little 14' Valiant.We sandwiched 2 pieces of 3/4" AC plywood together with fiberglass, dry fit it, rigged all kinds of stuff to get any bow out of the hull/transom joint and its pretty tight.Being a total newbie I have asked for lots of advice. I've gotten so many different opinions from so many different people on the best method for attaching it to the hull and I have kinda narrowed it down to 2 options. Please tell me what you think.
OPTION 1: I was told to use this stuff called Cabosil. My local Marina sold me West systems #406, colloidal silica, they said its the same stuff. The plan is to mix this with my resin(non blushing epoxy) to the consistancy of peanut butter.Spread it with a notched trowel using enough to fill any voids(if there are any they're very small), join the transom to the hull & clamp the snot out of it.
OPTION 2: Use fiberglass mat and epoxy resin in between the transom and the hull being pretty generous with the resin and then put them together and clamp the snot out of it.
Is one method better than the other? Any other suggestions? How cold is too cold to do this? Its getting chilly at night here.Thanks as always for any input.

 

[drewmitch44]

Re: transom installation stuff

If you can post some pics as your going i would learn a lot from that. Good luck!

 

[beerrun]

Re: transom installation stuff

I will. We had a busy summer and didnt get much done but theres pics where we started at share a project.I dont know if I put this link in properly or not, I hope it works.

http://www.shareaproject.com/pages/projectTut,p,337,00.html

 

[tashasdaddy]

Re: transom installation stuff

on the lower part you can also drill it and use bolt, washer, and nuts, where you can't clamp, then fill them later. you are on the right track.

 

[ezmobee]

Re: transom installation stuff

Glad to see you're still working on this. I thought that was a cool old boat and was hoping you'd finish it. Thanks for the progress pics. Did you do any work to that old Evinrude?

 

[beerrun]

Re: transom installation stuff

Yes I did. Gave it a tune up, found a pressurized gas can for it and it fired right up. amazing! I found a long shaft for it so I need to switch that out. I think it will work fine I'm just wondering if 30HP will be enough. I may eventually want something bigger and then the old evinrude will be for sale.
Its been so long I'm surprised you remember it.
Thanks for the answers.

 

[sdunt]

Re: transom installation stuff

Either method of 'cementing' the transom to the outer skin will work.. One thing to be careful of is unless you get the special kind of fiberglass mat, it is not compatible with epoxies.

Check out the last entry on this page: http://www.uscomposites.com/mat.html

1st off mat is held together with a binder that dissolves in Styrene, the thinner in polyester resin, so the mat will remain stiff with epoxy.

2nd some epoxies do not react well with the binder chemicals in the mat.

You can use clothe just as well as the mat, the mat holds more resin than the clothe does.

I've got a layer of mat, a layer of 7.5 oz clothe, and a second layer of mat behind my transom: http://www.shareaproject.com/pages/imageDetail,p,148,i,3251,00.html

 

[60 grit sandpaper]

Re: transom installation stuff

would too much mat make the transom too thick so the cap would not fit on?

 

[tashasdaddy]

Re: transom installation stuff

i saved my 58 35hp. in storage, just in case i wanted to go back to more original. i have had a 71 50 on it, and a 93 40 on it. you can see my project here.
http://forums.iboats.com/forumdisplay.php?s=&daysprune=-1&f=293

 

[sdunt]

Re: transom installation stuff

would too much mat make the transom too thick so the cap would not fit on?

True, when you're dealing with a split hull - deck with splash well, yes, you can make the transom too thick. I was fortunate that I didn't split the boat and I was trying to work around the differences in the hull and deck thicknesses.

But, yes you can over do it. but it also depends on the design of the boat.

 

[beerrun]

Re: transom installation stuff

Thanks for all the input. We went with option 1.
OPTION 1: I was told to use this stuff called Cabosil. My local Marina sold me West systems #406, colloidal silica, they said its the same stuff. The plan is to mix this with my resin(non blushing epoxy) to the consistancy of peanut butter.Spread it with a notched trowel using enough to fill any voids(if there are any they're very small), join the transom to the hull & clamp the snot out of it.
I am hoping we got enough goo behind there. We went pretty thick with it and some stuff was oozing out the edges so I think we did. We got pretty creative with the clamping part and I hope we got everything pulled together tight. I will find out tomorrow night. Is 24 hours long enough to let it set before I take the clamps off? We made the new transom the same width as the old so I have my fingers crossed that the top will go right back on.
Tashasdaddy, How many boats have you rebuilt?? You seem to have an example of everything.No wonder you know so much stuff. The Duracraft turned out great! The seats are ingenious but how comfortable are they?

I will try to get some pics on here tomorrow night of the progress so for.

 

[beerrun]

Re: transom installation stuff

Heres some pictures. Everything seems to be tight and strong. We are going to put the top back on this week. Does it make sense that I am thinking the top should go on before deck goes in? I'm worried about not getting the top to fit if we do it the other way around.I am attaching a link to my share a project page too. Theres more pics there.http://www.shareaproject.com/pages/projectTut,p,337,00.html

 

[sdunt]

Re: transom installation stuff

Does it make sense that I am thinking the top should go on before deck goes in?

YES, ABSOLUTELY. With the deck off and the floor out the hull has spread, and you are going to have to pull the hull together to get the deck back on. Dave Anderson in his book 'Runabout Renovations' campaigns for only replacing one at a time either the floor or the transom. He comes down on the side of NOT stripping the entire hull down. Remember that when that hull was built and the manufacturer installed the stringers, floor and transom it was being held in alignment in a mold. The hull was in effect setting in a bathtub until they where ready to join the deck and then they popped it out and put the two halves together.

I have a 14 foot glastron to work on next and I am planning to replace the stringers and the floor, back to within 1 foot of the transom, with the deck on the boat. Then I will pull the deck to get at the transom and replace it along with finishing that last 1 foot of the floor like I did on the last boat:
http://www.shareaproject.com/pages/imageDetail,p,148,i,3424,00.html

 

[beerrun]

Re: transom installation stuff

Yeah, I too have that book. (Its by Jim Anderson by the way) Unfortunately I got the book after everything was torn apart. I think it will be OK getting the top back on. I am just thinking that to go any farther with no top might lead to problems. We will find out tonight. I will post more pics.Thanks for the input and good luck with your boat.

 

[beerrun]

Re: transom installation stuff

Hey, the top is back on. YAY!!! It went on no problem. I was so relieved when it just dropped right into place and all the rivet holes lined right up. Tonight we re-riveted and cleaned it up a bit but heres a pic with the top just sitting there.
I will post pics of it clean tomorrow night. Sorry all my pics are always a day late, I dont have a cable for my camera so I have to go make discs.
I am thinking that the next thing I need to do is get some bunk boards on the trailer so the boat has more support before I get in there and start stringers.I am also still debating on whether or not to do a bilge pump. All that was there before was a drain hole. I am not sure about how to go about adding one though. Any suggestions? experience?

 

[ezmobee]

Re: transom installation stuff

I am thinking that the next thing I need to do is get some bunk boards on the trailer so the boat has more support before I get in there and start stringers.

This would be a good idea. If the weight isn't evenly distributed you could cause damage when walking around in there especially if there's no deck at the time.