1976 Grady White Transom Rebuild

[Slager]

In the picture you posted, there is only a sister on one side of the joint. The thru bolts in that picture are probably used because the sister isn't very big/not a lot of glueing surface. Because of space limitations from the gas tank location, I used only one sister on my stringers. I made the sister board extend aprox 12" to either side of the joint and used thickened epoxy glue. I used some counter sunk screws to clamp the glue and I just glassed over them. I ground off the excess glue so that my polyester resin would stick properly. Including screws or bolts into the joint won't hurt anything, but aren't necessary if you have a big enough gluing surface and use epoxy glue.

 

[kcassells]

Well like I said you need to do BOTH sides. Bigger is better, Like 8" to 12" ea. side meaning 16" for a butt joint overall. I used PB for the adhesive then clamped together on other scenarious I screwed but dip the screws in pb the reset the screws after a test fit.
Slager is on the $$.

 

[demarko210]

I could not use poly to make this bond?

 

[kcassells]

Yes you can use poly. Thats your only option since you are rolling with it. Wanna cracker?

 

[Slager]

Yes, you can use poly. If using poly, I would definitely put a sister on both sides of the joint and use screws that go through all three pieces of wood and put some screws from both sides. Because poly isn't as good of a glue, the screws need to be left in there to handle some of the load.

 

[demarko210]

Yes you can use poly. Thats your only option since you are rolling with it. Wanna cracker?

lol a cracker would be nice, chicken and biscuit my flavor. Thanks man!

 

[demarko210]

Yes, you can use poly. If using poly, I would definitely put a sister on both sides of the joint and use screws that go through all three pieces of wood and put some screws from both sides. Because poly isn't as good of a glue, the screws need to be left in there to handle some of the load.

Sisters i will uses thanks.

 

[demarko210]

Wow, hope my gas tank can still fit. Would it be better to use epoxy just to joint these joints? Making sure I know the location of the glue?

 

[kcassells]

Hey when making pb w/poly you HAVE to add chopped glass or it has no strength at all. You should not mix poly and eeeeeeeeepppppppppoxyyy. Just stay w/ poly,, it's fine. most boats are made w/poly.

 

[demarko210]

Thanks kc. What wood should I get for the stringers? I realized I bought (4) 4 x 8 23/32 A/C 28.85 each and the stringers are 1 inch. Ok for the transom. The Lowes does not sell 1/4 in that brand. Could I uses the 2x10 for the stringers non pressure treated? Or could I just build up thickness of the 23/32 with biax

 

[demarko210]

I sent the gas tank to the shop to get the mounting brackets fixed. The welding shop up the street from my house. The guy said he would pressure check it for me and weld and new mounting bracket on. The other 3 have a little crack in the bracket. He will take care of that too. $50 can not complain. I just sold my 18 gallon tank on the-ebay for 125 will be shipping that today. I will buy a new sending unit for this tank and a new fill hose with this money. They guy i bought from said it was good, came from MI and he said it was tested. Check again WTH.

 

[demarko210]

they had this at the depot
https://drive.google.com/open?id=0B95_CdtAK79BUDBIWXQ5N1c2bXM

https://drive.google.com/open?id=0B95_CdtAK79BWXNocHM5UTRhQVU

 

[Slager]

Were the original stringers made from dimensional lumber? I wouldn't use dimensional lumber for the stringers. Plywood is much stronger and less susceptible to warping over time. You could return the 3/4 and use 1/2 in plywood and laminate it together to form 1 in, or laminate a piece of 3/8 to the 3/4 and be a bit thicker.

You could build up the thickness with glass and resin but that would be the most expensive and be more work.

Also when putting sisters on your butt joint the total thickness of the two sisters together should be equal or greater than the stringer.

 

[demarko210]

Were the original stringers made from dimensional lumber? I wouldn't use dimensional lumber for the stringers. Plywood is much stronger and less susceptible to warping over time. You could return the 3/4 and use 1/2 in plywood and laminate it together to form 1 in, or laminate a piece of 3/8 to the 3/4 and be a bit thicker.

You could build up the thickness with glass and resin but that would be the most expensive and be more work.

Also when putting sisters on your butt joint the total thickness of the two sisters together should be equal or greater than the stringer.

I not sure if it was made from dimensional or not. This is the second time I ever cut wood. The wood A/C i got at the lowes says its Arauco. it has 7 ply. if I can find some 1/4 4ply could use that to make the 1" or would that wood need to be the same exact type?

I thought about building the thickness and like you said i realized to much money.

So i will use 2 sisters and probably will be the 23/32 left over making total width about 2.75 at the joint...

 

[demarko210]

I have my transom cut out with (2) 23/32. i have test fitted one board but not both together at the same time. When I sandwhich the boards together with glue should I use PL Glue 3x? And if I use PL do I need to wet the board with resin first then let dry then PL? I was thinking the PL says water proof I could save the money and not use the resin between boards. Then wet out the rest of the board with resin.
or
Resin both sides of each board then sandwich resin only?

https://drive.google.com/file/d/0B95...ew?usp=sharing

 

[kcassells]

Were the original stringers made from dimensional lumber? I wouldn't use dimensional lumber for the stringers. Plywood is much stronger and less susceptible to warping over time. You could return the 3/4 and use 1/2 in plywood and laminate it together to form 1 in, or laminate a piece of 3/8 to the 3/4 and be a bit thicker.

You could build up the thickness with glass and resin but that would be the most expensive and be more work.

Also when putting sisters on your butt joint the total thickness of the two sisters together should be equal or greater than the stringer.

I do like Slager recommended.

 

[kcassells]

This is from Woodonglass, you shoiuld read it. It will answer alot of questions and is a Must read;
1961 Lonestar Flamingo - SPLASHED...Kinda!!
Fabricating Decks, Stringers, and Transoms
Paint Your Boat with Tractor Paint...Say What!!!

 

[demarko210]

Slager

Ok now I realized the difference between the wood after I had a good night sleep. The current wood that is in the stringer is not plywood, I dont think.:indecisiveness:
Reason I am saying I dont think its plywood is because i do not see any layers in the wood like I do with the current plywood I have. When I dig out the transom i could see layers of wood. Here is a picture of one of the stringers.

https://drive.google.com/file/d/0B95_CdtAK79BT3ZBY2hmQkdwTTQ/view?usp=sharing

 

[demarko210]

Hey when making pb w/poly you HAVE to add chopped glass or it has no strength at all. You should not mix poly and eeeeeeeeepppppppppoxyyy. Just stay w/ poly,, it's fine. most boats are made w/poly.

I have some fumed silica, I did not get any chopped glass. How many pounds do you think I should get?

 

[Slager]

Slager

Ok now I realized the difference between the wood after I had a good night sleep. The current wood that is in the stringer is not plywood, I dont think.:indecisiveness:
Reason I am saying I dont think its plywood is because i do not see any layers in the wood like I do with the current plywood I have. When I dig out the transom i could see layers of wood. Here is a picture of one of the stringers.

https://drive.google.com/file/d/0B95_CdtAK79BT3ZBY2hmQkdwTTQ/view?usp=sharing

Essentially, a common theme here on Iboats is that you can go back the way the manufacturer did it if you want. Most people look at what the manufacturer did and decide to improve it. Plywood is much more suitable to forming a stringer, but if you want to replace it as you found it, you can. Dimensional lumber has a tendency to swell and warp with changes in humidity and temperature, plywood is much more stable. When the wood swells, it can slowly break the laminated fiberglass away from the wood. Also plywood gives you more strength.