Mast step replacement

Mar 9, 2023
19
Catalina 22 1320 Dittmer
A 1/2" hole would probably be enough to get a look. It's fairly easy to fill and can be done under the mast step
Very good. I was considering measuring an inch out from where the step is mounted on all 4 sides, then removing the top layer of fiberglass. Get a for sure view of the underlayment, then fill it back in after some dry time if moisture was present. Popping out the compression post would give me a great view of where the bolt enters for any issues. Anything more than that and I was going to claim, "Above my pay grade". I'll continue with the 1/2 holes for now.
 
Nov 12, 2009
259
J/ 32 NCYC, Western Lake Erie
Here's another approach you could consider. Put the mast step in position where it belongs. Trace around the mast step. Then make another line inside the mast step footprint half an inch from each side - so if your mast step is 4 inches by 6 inches your new lines would be 3 inches by 5 inches. Cut the fiberglass deck out in this area to check for rot and any interior damage. Then it's easy to repair/replace the damaged material because you have a reference plane on all 4 sides. And if you don't get a perfect repaired surface the repair is covered by the mast step.
 
Mar 9, 2023
19
Catalina 22 1320 Dittmer
Here's another approach you could consider. Put the mast step in position where it belongs. Trace around the mast step. Then make another line inside the mast step footprint half an inch from each side - so if your mast step is 4 inches by 6 inches your new lines would be 3 inches by 5 inches. Cut the fiberglass deck out in this area to check for rot and any interior damage. Then it's easy to repair/replace the damaged material because you have a reference plane on all 4 sides. And if you don't get a perfect repaired surface the repair is covered by the mast step.
Even better. Thank you!
 
Sep 24, 2018
2,978
O'Day 25 Chicago
Technically speaking you should be tearing away fiberglass until you find good, dry core material. In my opinion it's not practical for our older, smaller boats. I tore away an area about the same size as my mast step, let it dry out (fans help reduce this from weeks to days), sealed off the area to prevent damage to the new core and proceeded with the repair. Search my threads as I'm in the process of this repair now. There's a few good tips that may help you
 
Mar 9, 2023
19
Catalina 22 1320 Dittmer
Technically speaking you should be tearing away fiberglass until you find good, dry core material. In my opinion it's not practical for our older, smaller boats. I tore away an area about the same size as my mast step, let it dry out (fans help reduce this from weeks to days), sealed off the area to prevent damage to the new core and proceeded with the repair. Search my threads as I'm in the process of this repair now. There's a few good tips that may help you
Read your thread and all the suggestions. Saved the site for working with glass from West Marine. To clarify, what process did you go with? Based off the substrate (plywoods) options.
 
Sep 24, 2018
2,978
O'Day 25 Chicago
Read your thread and all the suggestions. Saved the site for working with glass from West Marine. To clarify, what process did you go with? Based off the substrate (plywoods) options.
I used a small piece of marine plywood. That's what O'Day used when it was built. I figured it lasted 40 years so it'll outlast the boat. Looking back I probably should've used two layers of 1708. I've done fiberglass work before but literally just dove in and went to work. I made a few mistakes. I will go through every step of the process just before diving in so I don't forget anything next time. An oscillating tool, even if it's from Harbor Freight, is worth it's weight in gold. I have not found a significant difference between Milwaukee and Chinese cutting blades
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,040
CAL 35 Cruiser #21 moored EVERETT WA
I have not found a significant difference between Milwaukee and Chinese cutting blades
I agree:plus:
Just experienced the use of both on some large (1.5" dia) bronze thru-hull nuts. To resolve the removal of a broken Knot Transducer, the Milwaukee blade made the first cut. No break out. On cut two I got about 2/3'ds way thru the nut when the cutting stopped. The blade had lost the teeth on half the blade. Off to Harbor Frieght. Purchased two blades. One their Best brand (Hercules) and the other the OK brand (Warrior). I put the OK brand on the oscillating tool. I finished the Transducer removal, then went at the Black Water 1.5" dia bronze thru-hull. The blade finished the job. Not sure if the blade is finished, just happy the task is complete. :biggrin:
 
Jan 19, 2010
12,543
Hobie 16 & Rhodes 22 Skeeter Charleston
A 1/2" hole would probably be enough to get a look. It's fairly easy to fill and can be done under the mast step
I fill holes in wood using white oak dowel or pine rods… white oak is better than pine…NEVER use red oak…. It will rot easily. I put a dab of Gorills glue in the hole and tap in the dowel with a hammer…. Then trim the excess dowel with a chisel… sand
 
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jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,040
CAL 35 Cruiser #21 moored EVERETT WA
Then trim the excess dowel with a chisel…
I use a thin blade Japanese draw saw (Nokogiri) to cut the dowel plug. Less chance of cracking/splitting the plug.
 
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Sep 24, 2018
2,978
O'Day 25 Chicago
I usually mix some thickened epoxy and inject it with a syringe into the hole. Then I cover the hole with a piece of tape. The tape makes it so there's little to no sanding. I've also found that the epoxy will cling to it a bit which is helpful when the hole is on a vertical surface or there isn't enough filler mixed in. Counter sinking the hole gives more surface area for the epoxy to adhere and in theory provides a better seal/adhesion.
 
Mar 9, 2023
19
Catalina 22 1320 Dittmer
I usually mix some thickened epoxy and inject it with a syringe into the hole. Then I cover the hole with a piece of tape. The tape makes it so there's little to no sanding. I've also found that the epoxy will cling to it a bit which is helpful when the hole is on a vertical surface or there isn't enough filler mixed in. Counter sinking the hole gives more surface area for the epoxy to adhere and in theory provides a better seal/adhesion.
Today I'm going to continue the drilling to identify the extent of possible rot. Have watched so many videos from drill to removal of an area triple the size of the mounting area. (Not a fan as glassing will be a new event in my life lol). Then off to the marine store, West Marine - 33 miles, to learn the basics. Probably get some extra stuff to practice with on material laying around before I attack the boat cracks!
 
Sep 24, 2018
2,978
O'Day 25 Chicago
Today I'm going to continue the drilling to identify the extent of possible rot. Have watched so many videos from drill to removal of an area triple the size of the mounting area. (Not a fan as glassing will be a new event in my life lol). Then off to the marine store, West Marine - 33 miles, to learn the basics. Probably get some extra stuff to practice with on material laying around before I attack the boat cracks!
West Marine is one of the most expensive sources for epoxy resin but one of the few that has it locally. I've used West Systems, Total Boat and E-bond epoxies. I'd recommend the first two for beginners. I don't notice a difference between them. E-bond forms a much heavier amine blush layer if it's not covered

You can start with a small hole and open it up as needed
 
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Mar 9, 2023
19
Catalina 22 1320 Dittmer
First picture is viewing aft. You can see a difference in the ply's. There was a seam there throughout the entire length of the cut. Everything to the port of the seam is dry. Everything removed from the starboard side of the seam was bad. Fiberglass is seen in one area and the rest had no fiberglass. The wood seen now is another layer of core, then the interior fiberglass. Continue drilling to starboard till dry? Or build up the step area (area cut out) with epoxy?
 
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dmax

.
Jul 29, 2018
1,076
O'Day 35 Buzzards Bay
Keep drilling till you get all the wet wood out and let it dry out a bit if you can as well. You've done all this work, might as well get it all. Hopefully you can scrape it out without having to remove any more of the deck. Good luck.
 
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Mar 9, 2023
19
Catalina 22 1320 Dittmer
Keep drilling till you get all the wet wood out and let it dry out a bit if you can as well. You've done all this work, might as well get it all. Hopefully you can scrape it out without having to remove any more of the deck. Good luck.
Thinking continue on with the 1/2 bit or go smaller since I'm in the non slip area to continue investigating?
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,040
CAL 35 Cruiser #21 moored EVERETT WA
Ken.. You have a 22 ft boat that I suspect you are looking to use for recreation not racing or sailing across oceans.

The would lead me too believe the boat will be used moderately not pushed to the extreme.

You need to be the judge when to stop digging.
  • The area too starboard (the bad ply) is it rotten, punky, crumbling separated from the fiberglass deck
  • or is it wet but in contact with the fiberglass deck.
If it is structurally solid/together as plywood - not rotten dust, I would seek to leave it in place and once dry use a PENETRATING EPOXY SEALER like this at TotalBoat.
This will, when dry, bind the ply's together and provide the structure you need on that part of the deck without removing more of the deck skin.

In the area you have excavated, you will want to put a new piece of plywood. Attach the new piece to what is in the "hole" with some thickened epoxy. This will give you a solid base for your mast.

Then you will want rebuild the deck with fiberglass layers. Here you want to use a laminating resin as it will permit you to build the layers. Andy, at the link to BoatworksToday.com , demonstrated how to use laminating resin and glass mat & woven cloth to build the deck back up.

Once you complete the deck you will then drill holed for your bolts/screws At that point you will use the epoxy plug to make sure no water gets through the deck into the core.
 
Mar 9, 2023
19
Catalina 22 1320 Dittmer
Ken.. You have a 22 ft boat that I suspect you are looking to use for recreation not racing or sailing across oceans.

The would lead me too believe the boat will be used moderately not pushed to the extreme.

You need to be the judge when to stop digging.
  • The area too starboard (the bad ply) is it rotten, punky, crumbling separated from the fiberglass deck
  • or is it wet but in contact with the fiberglass deck.
If it is structurally solid/together as plywood - not rotten dust, I would seek to leave it in place and once dry use a PENETRATING EPOXY SEALER like this at TotalBoat.
This will, when dry, bind the ply's together and provide the structure you need on that part of the deck without removing more of the deck skin.

In the area you have excavated, you will want to put a new piece of plywood. Attach the new piece to what is in the "hole" with some thickened epoxy. This will give you a solid base for your mast.

Then you will want rebuild the deck with fiberglass layers. Here you want to use a laminating resin as it will permit you to build the layers. Andy, at the link to BoatworksToday.com , demonstrated how to use laminating resin and glass mat & woven cloth to build the deck back up.

Once you complete the deck you will then drill holed for your bolts/screws At that point you will use the epoxy plug to make sure no water gets through the deck into the core.
You are correct in its intended use, recreational. Blue water is planned post retirement and in a bigger boat . I'll check the distance to the layers still intact and hopefully I'll only need to drill enough to inject the sealer. I have watched the videos created by Andy and feel comfortable with the glass aspect...but still watching more Thank you for the guidance!
 
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dmax

.
Jul 29, 2018
1,076
O'Day 35 Buzzards Bay
I had some core-rot on my boat and was able to dig 4 - 5 inches from the opening's edge (all that was necessary) using a long thin screwdriver that I bent the shaft at about a 30 degree angle. Don't inject epoxy into wet wood, it won't do anything and just make it harder to fix later. It would be good to use a moisture meter to determine the extent of the moisture - borrow one if you can, Ryobi has a $40 one that will tell what your up against.
 
Mar 9, 2023
19
Catalina 22 1320 Dittmer
I had some core-rot on my boat and was able to dig 4 - 5 inches from the opening's edge (all that was necessary) using a long thin screwdriver that I bent the shaft at about a 30 degree angle. Don't inject epoxy into wet wood, it won't do anything and just make it harder to fix later. It would be good to use a moisture meter to determine the extent of the moisture - borrow one if you can, Ryobi has a $40 one that will tell what your up against.
Appreciate the suggestion and have a friend that owns one. Sounds like he needs to come over for dinner
 
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