1971 20 SF Transom project

[Yamtt125]

Well, its about time I start working on this boat if I want to get it done by next spring. I am first beginning with the transom, then I plan on raising the deck and doing other fun and exciting things with her!!! lol.

So far, I have cut out the back of the boat and removed the wood the was previously there. By the picture, you can obviously tell it wasn't in the best condition to say the least.

In the next couple of days, I plan on finishing grinding/ sanding down the inner fiberglass.
Does anybody suggest any particular type of grinder I should use for that..?? And, does anybody have any suggestions on how to get the white crap off the went on the sides and bottom wood in the transom....that is some hard stuff!!!


I also plan on using Douglas fir for the transome....does anybody have any reasons why not too????

Also, I have a couple quick questions on some other random stuff about the boat:
My boat doesn't have any type of core under the gunels, and i thought it was kinda wierd cause most boats do...right??

My sf doesn't have any foam under the deck. I thought that most seacrafts had foam under the floor. Or is that only MA's??

Also, I want to use the talk it came with because its in good condition and I was wondering if anybody knew how many gallons it is. Its the tank that went under the console.

Thanks in advance guys
-Andrew






Here is the crazy hard white stuff I can't remove...

[quonie]

Well I'll be darn. I asked on another thread if anyone tried removing the wood core on the transom from the inside and didn't get a response.
What made you try this method?
Can you show a picture from the stern? Do you plan on building the transom up higher or close the whole thing in?
Your question on the fir. Better off using a high grade marine ply. As for a tool someone suggest a Fein Multimaster
on another thread in this section.Never used one myself but will try it out soon. Where are you located? Keep us updated with the progress

[Yamtt125]

Quonie,
I am doing it from the inside because I plan on puting a new floor in and reconstructing the livewell and bilge access area, so why cut up the outside of the boat when I am going to cut up the inside?
I will get a picture of the stern as soon as a get a chance.
I plan on raising the transom 5in.
thanks for the responce

[strick]

Does anybody suggest any particular type of grinder I should use for that..??




dougfir is soft and holds moisture. Also I dont think they make sheets big enough to cover the entire transom. Use marine grade plywood or composite like Cosa board. air chisel works for the "white stuff"

strick

[Bigshrimpin]

DougFir A/B marine ply is what I used for my transom.

[Yamtt125]

BigShrimp,
Whats the difference between dougfir and dougfir marine ply?
Is one softer than the other?

Strick,
what type of tool did you use with that disk?...how many amps was it? Do you recomend a particular manufacturer?

Thanks for the responces.

Still looking for any info on the size of the tank I have and why nothing my boat was cored with plywood or anything.

[WillyC]

A 4 1/2 inch grinder is what you need. I bought the Makita from home depot about $100. I think its 5 amps. That tool and a shop vac are two things that you cant do without. You will be using them almost every day. Happy grinding!

[warthog5]

The standard is A-B Douglas Fir marine.

There is no diffrence in the wood in Doug Fir [DF] ply's and DF marine ply's, except the marine has a higher standard about void's. The marine has basicly no void's.

There are other maine plywood's. [Okoume & Meranti]

I personally would not use them as a transom core. They are more expensive and have better/smoother outer ply's.
They would be a excellent choice if you were building a whole wooden hull.

The transom core on the boat's we have is highly imbeded in fiberglass on both side's, so that super looking surface on Okoume is $130 a sheet & Meranti is $95 a sheet mean's nothing. A/B DF Marine here is $74 a sheet.
Any of these plywood's need extra attention to the end grain and any holes you bore thru it.

[strick]

Looked back at he post. Sorry my bad... I thought you were talking about using doug fir planks for the transom. Your choice on transom material depends on how much you want to spend and if you are worried about a little extra weight and water intrussion. The transom's in these boats were made of plywood and they lasted 30 years. So if you re do it properly with plywood then the transom should last another 30 years. The main thing is like Bobby said you have to pay special attention every time you drill a hole in the back of your boat that you take precautions to keep the water out of the wood. I re-did my transom with plywood. It may be a little on the heavy side but it's solid. I may try that coosa board on the next transom I do....seems that is what everyone is doing these days. It is 30% percent lighter then plywood which is not really all that much weight difference if you are just re-doing the transom... if you are redoing the entire boat then it adds up.

strick

[Yamtt125]

Will, thanks for the advice about the grinder. Tonight I just sanded out the small particles of wood the were embedded in the resin they used when the boat was made.

Wart, thanks for the information reguarding the wood. I'm iehter gonna use the regular dougfir, or the marine grade. Like strick said, if the origional lasted 30 yrs, then the new one should too. And I will deff be happy if the new one last another 30 yrs. If you think about it, in another 30 yrs, the boat will prob need another major facelift anyways, so I don't see too many advantages with going with coosa anyways.

Grady,
After seeing you start your project, It deff gave me the motivation to move a little quicker than i was before. Yours is coming along great. How do you like the results of the fairing compound you used?? I have to decied on what kind I'm going to be using for my floor and other things.
I'm deffinately gonna use trayders and marks boats as guides.

How smooth or rough should I leave the transom? Right now i'm using 60 grit paper with the orbital. Hopefully tomorrow I will finish up the sanding, and chissel away the small amount of the old cabosil mixture.

Thanks for all the responces. Tomorrow I will post new pics of the transom.
-andrew