Here is what is involved when we do bottom work to repair or replace a traditional bottom. No, I am not asserting that our way is the only or the best way. What follows below is what currently works for us today. However, preserving wood vessels is an evolving journey along which best practices and best materials evolve continually. Remember that there was a day when paying 5200 into bottom plank seams was dogma! But flexible marine epoxy products were not even a glimmer on the researcher’s bench then.
No well-informed restorer would ever, ever, ever pay 3M5200 into bottom planking seams today.
Why? Watch our Why Filling Seams With 3M5200 Is Forbidden video.
Following is our sequence, particularly the materials and methods we use and where you can get them:
- Strip the bottom
- Tools:
- Refasten planks & fill countersinks
- Silicone Bronze wood screws flat head Frearson – #8 x 1-1/2 & #10 x 1-3/4 Flathead Frearson silicon bronze
- Silicone Bronze wood screws flat head Frearson – #8 x 1-1/2 & #10 x 1-3/4 Flathead Frearson silicon bronze
- Filling/’fairing countersinks –
- 3M Marine Premium Filler
- Tools – flexible putty knife or plastic compound spreader
- Fill plank seams – TotalBoat Thixo Flex Flexible Epoxy Adhesive
- Tools
- Piston-driven pneumatic or battery-powered caulking gun
- Flexible putty knife
- Vice grips for changing mixing tube
- Sand bottom and chines –
- Sixty grit followed by 80 grit paper.
- Using either an inline or random orbit sander is fine, since you need not worry about cross-grain scratches beneath paint. If you use the random orbit sander, do take special care to keep it moving constantly, less you create a moonscape that you truly do not want.
- Tools
- Seal – Apply FOUR full coats on Smith’s Clear Penetrating Epoxy Sealer – CPES. Apply the first two coats immediately one after the other. (Use the inexpensive alternatives on the market at your peril.)
- Prime – Apply FIVE coats of Interlux InterProtect 2000E Barrier Coat Epoxy Primer
- Alternate between applying gray and white. Minimum recoating at 60F (15C) is 5 hours. Maximum interval is 6 months.
- Alternate between applying gray and white. Minimum recoating at 60F (15C) is 5 hours. Maximum interval is 6 months.
- Apply bottom paint – at least three coats
- Ablative (Antifouling), if the boat lives in the water all season
- Pettit 1933 Copper Bronze Antifouling Bottom Paint
Hard if the boat is dry sailed – Pettit Old Salem Copper Bronze Hard Racing Enamel.