Bondo in my transom?

[Emayr]

I am in the process of removing the transom, on my 98 Baja 232.
Now that I have almost all the plywood removed. I noticed what appears to be bondo as the bonding and fillet material.

Is this what they used at the factory? I really expecting to find thicken resin.

 

[Scott Danforth]

Could be, could be a marine filler vs auto filler

 

[BillP]

Contrary to popular belief most small boat mfgs don't use thickened anything to bed ply transoms. Nor do they put a glass layer between plys or against the hull skin. It does noting but add labor, expense and weight. All they do is wet the skin with laminating resin and put the wood in, then glass it. There are exceptions but the industry is pretty standard in this regard.

 

[Redtruck12]

I think the general rule is manufacturing especially in the 80s & 90s did whatever cheap out shortcuts they could get away with

 

[Bondo]

I am in the process of removing the transom, on my 98 Baja 232.
Now that I have almost all the plywood removed. I noticed what appears to be bondo as the bonding and fillet material.

Is this what they used at the factory? I really expecting to find thicken resin.

Ayuh,...... Welcome Aboard,....... Bondo, is in fact just another poly based thickened resin,.......

 

[Woodonglass]

Why do you think it's BONDO?

 

[sphelps]

There are additives that turn the resin used reddish in color .. It may be that instead of reg bondo

 

[Scott Danforth]

half of the marine fillers use red creme as the hardener.

 

[kcassells]

Besides ....where are some pics?

 

[Emayr]

Keeps giving me a error that says file is to big

 

[Scott Danforth]

Keeps giving me a error that says file is to big

you cant post pics until your 4th pic (its in the rules) and your pictures need to be 700kb or smaller. most pics on a phone need to be re-sized. this is covered in the tutorial on pictures in the rules and guidelines forum

 

[Emayr]

Scott you mean 4th post right?

 

[fibersport]

This leads me to a question. Since body filler is a polyester resin, couldn't you use it for fillets? I had been thinking of the glass fiber stuff often called kitty hair. The fillets don't really add strength so does it really matter?

 

[kcassells]

Let's regroup........Bombdo has a flour filler in it that absorbs water. Same with ther marine version. In my opinion it has no place below deck or waterline.
Filets do add a % of strength. Make peanut butter or some mfg's version of PB. You can also use 3m 5200 but you need to let it gas of for awhile before glassing.
I would use Bombdo on my car...maybe.Review the specs.

 

[sphelps]

From what I have heard it’s the talc that’s in the reg bondo that is the reason to keep away from wet area’s .
It could absorb water and start to blister...

 

[kcassells]

Yea..yea that's it. It's the talc. yea. Couldn't get the word out of my head so I threw flower in there. Yea, yea that's it. :joyous:

 

[MTboatguy]

Regular automotive bondo, will blister if left under water for a prolonged period of time. They also make a marine version that won't because the fillers are different, I have seen it lots of times on both boats as well as RV's. I would imagine you ran into a spot of marine filler that is designed for underwater application. Also, you can use regular automotive fillers, but you have to seal them and I mean perfectly and they will hold up for quite a while. That said, with the variety of fillers on the market, there is no reason to use an automotive filler on a boat, you won't save any money or time over getting the correct material.

 

[Scott Danforth]

a gallon of lightweight marine filler is about $30.

 

[Dennischaves]

I’ve been doing auto body for almost 25years and I will say with 100% certainty that regular bondo will absorb water
there are a few automotive putties that are waterproof
as are most glass reinforced fillers

 

[fibersport]

If it's sealed with glass and resin, than it shouldn't matter. Any wood will eventually get wet as well, by then we will probably have sold it or be gone ourselves. Just thinking a little outside the box for something a little easier to deal with.