1971 14 ft Fabuglass Fury Transom rebuild

[ScottR]

Hello all,

I am in the process of rebuilding the transom on my 14 ft Fabuglass closedbow runabout.


We live on a lake that is limited to 15hp motors so these old runabouts are a fun alternative to a slow pontoon (I have a 24 pontoon with a 9.9 hp motor). I got the boat with new carpet, new seats, steering converted to teleflex, and mercury controls for $400 a couple years ago. I put on a new Merc 15hp and we got a fun little boat. I thought the transom was pretty solid but over time and some stand water has caused it to rot so I am replacing it this winter.

Here is a picture of the transom area with motor off before demo

and another


Here is a picture after some initial demo

and another


Have done more demo - basically have all the plywood off transom which was not fun but almost done. I will post pictures of where I am now later tonight. The transom is 1 1/4 thick and it looked like it had only one maybe two layers of glass on the inside. The floor of the well area was 1/4 thick ply covered in glass.

At this point I am mulling two different rebuilds. 1) The first is to rebuild it as it was with the 1 1/4 transom and put the 1/4 decking in the well area but include more access hatches. When I first got the boat there was no inspection port which lead to the standing water when the boat was in the water. 2) The second thought is to not put the decking back on and leave the bottom of the boat exposed (ie you can see stringers, bottom of boat etc). Either way and I am going to put a bilge pump in.

So my question is if I go with 2) above and leave the decking off do I need to increase the transom to 1 1/2 or so for straighten? The deck was glassed into the transom and I am assuming it gave it added strength like the rear seat of my GF 12. I am assuming if I go with no decking I can lower the level of the stringers (which are actually in decent shape except for the last 5 inches or so.)

Next question is with the old transom almost out the fiberglass skin is pretty flimsy. What is the best way to make sure the new transom is bonded to the old skin? I am not sure I have clamps deep enough for the bottom half of the transom.

Thanks for you help.

Scott R

[ScottR]

Here is a picture taken last night. I still need to grind/chisel/sand all the remaining ply still on the transom but I am getting closer.


and another


My big question is can I do away with the decking in the well area and reduce the height of the stringers? You can see from the pictures that the height was increased by adding wood on top the floor stringer and supporting it with glass and the plywood patches. If I do not add the decking and leave the well exposed as in the pictures will I need to increase the thickness of the transom? It was 1 1/4 thick with 1 layer of glass. My motor is a 2012 merc 15hp 4stroke weighing around 115.

Also what weight of glass needs to be on the inside of the transom. I know it should be bi-ax but does it need to be 17oz or is 12oz ok? I assume I will do at least two or three layers.

Thanks for your help.

[jacquesmm]

Joel is out fishing . . . He will be back Monday.
In the mean time, look at this:
http://www.bateau2.com/howto/transom.php
That is how I design the transoms and motorwells. Ideally, you should try to reproduce that: a pair of motorwell sides that go from the transom to the motorwell bulkhead and all the way to the bottom.
They can "sister" the existing stringers. It does not take much plywood and resin but would be very strong.
For the glass tape, we do almost all our tabbing with 12 oz. biaxial tape 6" wide.
Joel will tell you how many layers: you still have some cleaning to do but you are progressing nicely.

[ScottR]

Thanks Jacques! I was off line for the weekend doing Christmas stuff. Based the link it seems maybe I should go ahead and put the decking back on the motor well as original for the added strength. Correct?

Thanks for your time.

Scott

[TRC886]

I like the lines on your boat; it looks a lot like my 16' SilverLine

IMHO: That boat is rated for around 50-60 HP. Since you are limited to only 15 HP, a 3/4" transom with a 1/2-3/4" clamping board should be sufficient.

It is also my opinion that you can add a couple of knees and eliminate that bulkhead, or relocate it a few inches aft, to gain some cockpit space. Using Jacques design of a motorwell, a full width bulkhead with 2 motorwell sides, is extremely strong. Either of these options will be strong enough for the original motor rating...if you ever need it

I like option 1, eliminating the bulkhead and gaining the maximum cockpit space. I'd run the sole to the transom, except for a small bilge well that I'd add between the knees. This allows easy inspection of how much water may be under the sole, yields a lot more space in the boat, and gives a good sole to walk on, all the way to the transom

[tech_support]

1) The first is to rebuild it as it was with the 1 1/4 transom and put the 1/4 decking in the well area but include more access hatches.

that is what I would do. There needs to be a small hatch back there for access to the bilge

My big question is can I do away with the decking in the well area and reduce the height of the stringers? You can see from the pictures that the height was increased by adding wood on top the floor stringer and supporting it with glass and the plywood patches. If I do not add the decking and leave the well exposed as in the pictures will I need to increase the thickness of the transom? It was 1 1/4 thick with 1 layer of glass. My motor is a 2012 merc 15hp 4stroke weighing around 115.

those changes will dramatically reduce the strength and stiffness of the transom, which is no big deal if you never put more than that 15 on the transom

Also what weight of glass needs to be on the inside of the transom. I know it should be bi-ax but does it need to be 17oz or is 12oz ok? I assume I will do at least two or three layers.

well if your just going with the little motor, then a single layer of either would do the trick (assuming you replace the thickness of wood)

[ScottR]

Thanks Joel. I think I will rebuild it as it was but put in more hatches. The boat is rated for up to a 50 hp but I was surprised that the fiberglass looked to be only a layer think from the bottom of the transom to about the 6 inches short of the top. The top 6 inches looked like it had several layers maybe an 1/8 thick. I never really noticed the build up until I cut through the transom. I am assuming that was for added strength.

I neighbor saw my GF12 and got the boat building bug. He is in the process of building a Sharpie and put in an order for wood from you all few days ago. I had him order some extra for me so hopefully I will have the transom in over the next several weeks. Got to order some epoxy, glass and tape!

Scott

[TRC886]

It is also my opinion that you can add a couple of knees and eliminate that bulkhead

It appears that I have my terminology wrong

By "knees", I was referring to braces tying the transom to the stringers; such as this one on my tin boat:


Since making the post, I've seen other threads where "knees" were clearly used to tie the transom to the hull sides. This builder is using cardboard templates for his knees:

[tech_support]

you had it correct. "knee" has more than one connotation

[TRC886]

Thanks for the clarification, Shine

Can we post this link somewhere, maybe in the "Read This First" forum? I'm not the only one who needs a clarification on occasion.
http://www.seatalk.info/