Bow repair

[mavryk]

What is the best way to repair some scrapes on the bow of my 1988 Larson Bowrider? There is a little damage right below the waterline where the bow comes to a point, maybe 3-4 inches long. I am concerned about it starting to leak water. It is not crushed in, only abraded from beaching on sandbars (I think). Here is what I think I should do to repair, please chime in if I am doing it incorrectly.

1. Sand the damage and surrounding area to get a good, fresh surface to bond the new fiberglass.
2. Fill/level damaged area with bondo and sand smooth.
3. Clean area with Acetone
3. Apply a piece of wetted out CSM about 6" wider on each side and 12" longer than the damaged area.
4. After cured, fill/smooth with bondo and sand down smooth.
5. Clean area with acetone.
6. Apply new finish coat.


Tell me what I'm missing/doing wrong.

Thanks

 

[Sleeper-6]

Re: Bow repair

You've almost got it.

Here's what I would do.

1. Sand the damage and surrounding area to get a good, fresh surface to bond the new fiberglass.
Good start, get rid of all the damaged stuff be sure to feather out far enough out so the next steps will be flush with your existing hull

2. Fill/level damaged area with bondo and sand smooth.

Instead of bondo, use strips of CSM, starting with a narrow one directly on the damaged area. make each following piece a bit bigger. The idea is to build up the area back to it's original strength and thickness with glass, not filler. As a side note, make sure you're you are using an un-waxed resin here. you don't need the wax interfering with adheasion between layers.

3. Clean area with Acetone.

Sure, why not. Cleaner is always better

3. Apply a piece of wetted out CSM about 6" wider on each side and 12" longer than the damaged area.

No Need, you already did this in step #2

4. After cured, fill/smooth with bondo and sand down smooth.

Now you're getting it. Try not to sand into the glass, and be sure you're filler is recommended for use below the water line. Regular automotive Bondo brand is not

5. Clean area with acetone.

Clean is good

6. Apply new finish coat.

Exactly

 

[Woodonglass]

Re: Bow repair

Pics will help us to help you. I would not use bondo. It has talc and will absorb water. Based solely on your description you could probably sand away the gelcoat to fresh glass. Wash down with acetone an then apply Resin and multiple pieces of CSM progressively getting bigger to fill the area. Then use some 3M Marine filler to Fair in the low spots. Sand smooth and brush on 3-4 thick coats of gelcoat and sand and buff. If it's white it will look ok. Prolly won't match perfect but will be water tight.

 

[mavryk]

Re: Bow repair

Sleeper-

I understand what you are saying about laminating multiple layers. My only concern was if I would be leaving a small void behind the CSM strips, or do I just push the CSM and resin to "fill" the area and then smooth out the profile with the following layers?

Woodonglass-

Thanks for the info about the bondo. I assume 3M Marine filler is a material that is used in a similar fasion as bondo? 2 part mix into a putty, spread and sand?

Thanks for all the help.

 

[Sleeper-6]

Re: Bow repair

Once you wet the CSM it gets pretty mushy. the binders in it break down and you basically have tons of short strands held in place by the resin. Just stipple the areas of overlap with the tip of your resin brush and it will adhere nice and tight to the layer below. you can layup "wet on wet" too. Once you are happy with the way a layer is sitting go ahead and start the next one, you will get a better bond this way. The strength is in the glass, not the resin, so use a little resin as you need to properly wet out your layers, brushing on extra does you no good.

Good Luck

 

[Woodonglass]

Re: Bow repair

I really want to emphasize the importance of pictures for this process. It's almost impossible to give sound advice based solely on written descriptions. Your damage might only require a simple gelcoat paste repair or it might require the repairs as described by Sleeper and I. We can't be sure without the pics. You could possibly save yourself time, effort and dollars by posting some pics.:joyous:

 

[mavryk]

Re: Bow repair

Thanks guys. I am working out of state right now, but I will post some pics as soon as I get home and have a chance.

 

[Sleeper-6]

Re: Bow repair

Wood's got a point, I was picturing a bow worn through by repeated teachings. Maybe you're lucky and it's minor. The pics will tell.