Good Morning to all
I pulled a search of the site looking for information regarding lubrication of the portlight gaskets and came up empty handed...
What should I use on the gaskets?
SIDEBAR: Take faith Northern Brethern (sp). I had to mow lawn saturday, so surily spring in the north country is not far behind.
Bill
cd25d@rhapsodysails.com
Portlight Gaskets
Moderator: Jim Walsh
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Duncan Maio
Re: Portlight Gaskets
Bill:
The portlight gaskets are EPDM rubber, so you can use almost anything on them - I use light machine oil (like 3-in-1) on mine.
When it's time to replace the gaskets, you can get a 100' roll of 1/2" EPDM rubber cord from McMaster Carr (www.mcmaster.com, item 8605K44) for $28.11. Spartan gets $12 each for gaskets (they bevel the ends and glue them together), so buying in bulk is the way to go.
BTW, I have about half a roll if anyone wants to make me an offer. . .
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
dmaio@meganet.net
The portlight gaskets are EPDM rubber, so you can use almost anything on them - I use light machine oil (like 3-in-1) on mine.
When it's time to replace the gaskets, you can get a 100' roll of 1/2" EPDM rubber cord from McMaster Carr (www.mcmaster.com, item 8605K44) for $28.11. Spartan gets $12 each for gaskets (they bevel the ends and glue them together), so buying in bulk is the way to go.
BTW, I have about half a roll if anyone wants to make me an offer. . .
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
dmaio@meganet.net
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Matt Cawthorne
EPDM rubber?
Duncan,
I was told that the gaskets were made from closed cell sponge neoprene cord. I bought 50 feet from a rubber company in Chicago and thought that I was saving a buck. The appearance of the new sponge neoprene cord is the same as the old gaskets. Do you know what the difference between epdm rubber and neoprene is?
FWIW: When I bought the boat the gaskets were 12 years old and leaking. We replaced them with spartan parts. Getting the old ones out was really a time consuming mess. The job was typically at least an hour each. The old gaskets broke apart and chunks stuck to the frame and were hard to remove. This time I decided not to wait. This season my girlfriend has replaced the hatch and some of the port seals after what is now 6 years. The new seals come out easy because we did not wait until they got too degraded. The job now takes less than 20 minutes per port. I have been using a type of rubber cement to hold them in and it has worked very well.
Matt
mcawthor@bellatlantic.net
I was told that the gaskets were made from closed cell sponge neoprene cord. I bought 50 feet from a rubber company in Chicago and thought that I was saving a buck. The appearance of the new sponge neoprene cord is the same as the old gaskets. Do you know what the difference between epdm rubber and neoprene is?
FWIW: When I bought the boat the gaskets were 12 years old and leaking. We replaced them with spartan parts. Getting the old ones out was really a time consuming mess. The job was typically at least an hour each. The old gaskets broke apart and chunks stuck to the frame and were hard to remove. This time I decided not to wait. This season my girlfriend has replaced the hatch and some of the port seals after what is now 6 years. The new seals come out easy because we did not wait until they got too degraded. The job now takes less than 20 minutes per port. I have been using a type of rubber cement to hold them in and it has worked very well.
Matt
Duncan Maio wrote: Bill:
The portlight gaskets are EPDM rubber, so you can use almost anything on them - I use light machine oil (like 3-in-1) on mine.
When it's time to replace the gaskets, you can get a 100' roll of 1/2" EPDM rubber cord from McMaster Carr (www.mcmaster.com, item 8605K44) for $28.11. Spartan gets $12 each for gaskets (they bevel the ends and glue them together), so buying in bulk is the way to go.
BTW, I have about half a roll if anyone wants to make me an offer. . .
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
mcawthor@bellatlantic.net
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Duncan Maio
Re: EPDM rubber?
Okay, I did some checking, and while EPDM rubber is less resistant to petroleum products (but it's the same stuff they make radiator hoses from) it is highly resistant to cold, ozone, UV, and weather in general, and has a higher compression rating than neprene. It's also cheaper. It looks the same and, after two seasons, performs as well as neoprene.
I agree that replacement early is the way to go; I had a similar experience, and plan to replace them all every 4-5 years.
Without endorsement, a company that seems to sell anything that can be molded or extruded, in EPDM or neoprene, is at www.epm.com
BTW, does anyone have any tips for rebedding the portlights?
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
dmaio@meganet.net
I agree that replacement early is the way to go; I had a similar experience, and plan to replace them all every 4-5 years.
Without endorsement, a company that seems to sell anything that can be molded or extruded, in EPDM or neoprene, is at www.epm.com
BTW, does anyone have any tips for rebedding the portlights?
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
dmaio@meganet.net
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john churchill
gasket removal tool
i think i told you that they were neoprene. says so in the spartan catalog, at least. not great for uv resistance.
when i removed my gaskets, thay were about 12-13 years old. i cut a piece of 1/2" cpvc pipe at an angle of 45 or so and used it as a scraper. it holds an edge reasonably well, won't scratch the bronze, fits the groove ok, and (my favorite) is cheap as hell. i did not remove every peck off the groove, but close. used contact cement to affix the new ones in place. no leaks yet.
my criteria for replacement is when the portlight dogs bottom out. when new, there is considerable cushion to the gasket. this compresses over time and i theorize makes a poorer seal when there is no more cushion left. mine were way overdue at 12 years.
john churchill
when i removed my gaskets, thay were about 12-13 years old. i cut a piece of 1/2" cpvc pipe at an angle of 45 or so and used it as a scraper. it holds an edge reasonably well, won't scratch the bronze, fits the groove ok, and (my favorite) is cheap as hell. i did not remove every peck off the groove, but close. used contact cement to affix the new ones in place. no leaks yet.
my criteria for replacement is when the portlight dogs bottom out. when new, there is considerable cushion to the gasket. this compresses over time and i theorize makes a poorer seal when there is no more cushion left. mine were way overdue at 12 years.
john churchill
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matt cawthorne
Re-seal do not re-bed.
Duncan,
Thanks for the info. It sounds like you have found a much more economical replacement. After trying many sources I ended up finding the neoprene at $80 for 52 feet of cord + shipping. I'll check back in another 5 years or so.
I called the folks at Robinhood back in '93 and they recommended leaving the port in place and just removing and re-sealing the the trim ring on the outside. Removing the frame is difficult and unnecessary. You need to clear the old sealant out of the slot between the port frame and the hull, at least on the outside. I chose to use polysulfide instead of the original silicone. Two ports were leaking at that time. Clean up of the original parts was time consuming. Clean-up of the new polysulfide was even more time consuming. I am of the belief that those who go south when they die are put in a room with a leaking 8 ounce tube of polysulfide and all of the paper towels and acetone that they want. When they have the mess cleaned up they can go to heaven, but they never make it.
My technique to using polysulfide is to tape both the new trim ring and the cabin top. Then tape two more layers over the first. When the trim ring is finally in place wipe down the excess and put the paper towels and the gloves that you are wearing in a trash bag and take the trash bag to the dumpster. With new gloves and a fresh batch of paper towels and trash bag ready peel the outer layer of tape and then wipe down the joint again. Throw away your gloves and take the trash bag to the dumpster. Repeat. Do not wipe down after removing the last layer of tape. Any clean up after that should wait until the polysulfide is cured. Every time I try and skimp on this process I get into the polysulfide death spiral. Make certain that the bronze (both the trim ring and the frame) is cleaned of all corrosion before resealing things. If it is still corroded the water will work along the corrosion and ruin your work in a year or two.
Good luck. It can be very time consuming.
Matt
mcawthor@bellatlantic.net
Thanks for the info. It sounds like you have found a much more economical replacement. After trying many sources I ended up finding the neoprene at $80 for 52 feet of cord + shipping. I'll check back in another 5 years or so.
I called the folks at Robinhood back in '93 and they recommended leaving the port in place and just removing and re-sealing the the trim ring on the outside. Removing the frame is difficult and unnecessary. You need to clear the old sealant out of the slot between the port frame and the hull, at least on the outside. I chose to use polysulfide instead of the original silicone. Two ports were leaking at that time. Clean up of the original parts was time consuming. Clean-up of the new polysulfide was even more time consuming. I am of the belief that those who go south when they die are put in a room with a leaking 8 ounce tube of polysulfide and all of the paper towels and acetone that they want. When they have the mess cleaned up they can go to heaven, but they never make it.
My technique to using polysulfide is to tape both the new trim ring and the cabin top. Then tape two more layers over the first. When the trim ring is finally in place wipe down the excess and put the paper towels and the gloves that you are wearing in a trash bag and take the trash bag to the dumpster. With new gloves and a fresh batch of paper towels and trash bag ready peel the outer layer of tape and then wipe down the joint again. Throw away your gloves and take the trash bag to the dumpster. Repeat. Do not wipe down after removing the last layer of tape. Any clean up after that should wait until the polysulfide is cured. Every time I try and skimp on this process I get into the polysulfide death spiral. Make certain that the bronze (both the trim ring and the frame) is cleaned of all corrosion before resealing things. If it is still corroded the water will work along the corrosion and ruin your work in a year or two.
Good luck. It can be very time consuming.
Matt
Duncan Maio wrote: Okay, I did some checking, and while EPDM rubber is less resistant to petroleum products (but it's the same stuff they make radiator hoses from) it is highly resistant to cold, ozone, UV, and weather in general, and has a higher compression rating than neprene. It's also cheaper. It looks the same and, after two seasons, performs as well as neoprene.
I agree that replacement early is the way to go; I had a similar experience, and plan to replace them all every 4-5 years.
Without endorsement, a company that seems to sell anything that can be molded or extruded, in EPDM or neoprene, is at www.epm.com
BTW, does anyone have any tips for rebedding the portlights?
Duncan Maio
s/v Remedy
CD27 #37
Bristol, RI
mcawthor@bellatlantic.net
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John R.
Talc
I have always used talc. Most new rubber and weatherstrip has talc on it to preserve it. It prevents sticking and that prevents potential strain on the gasket when a port is opened and that reduces the chance of tearing or straining the seal. Talc preserves the flexibility of the Neoprene ( the CD seals are Neoprene not EPR/EPDM ).Bill wrote: Good Morning to all
I pulled a search of the site looking for information regarding lubrication of the portlight gaskets and came up empty handed...
What should I use on the gaskets?
SIDEBAR: Take faith Northern Brethern (sp). I had to mow lawn saturday, so surily spring in the north country is not far behind.
Bill
The Neoprene purportedly has slightly better UV resistance. You couldn't prove it by me and my experience of seeing them both used on a restored car that is exposed to Florida's brutal sun. They look the same. It's true that EPR/EPDM rubber is not as resistant to petroleum products as Neoprene. Again you couldn't prove it by me.
If you don't like the idea of talc; Spartan recommends silicone. Like I said I've been using talc, it doesn't attract dirt. The boat is an '83 and the seals are all the originals on the ports and hatches. Only one has just recently developed a very slight leak in heavy downpours. I think that seal was damaged by small debris that became trapped between the seal and the glass and thus permanently scarred the sealing surface of the gasket.
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Russell
We've been using an electric drill and brass wire brush whee
It is the smallest such brush wheel we can find, about 2" in diameter. The brush thickness fits inside the groove for the gasket. We tear out the old gasket, then use the brush to clean out any remaining old gasket material. The brush polishes the bronze, but if you are careful, only in the groove where the new gasket goes.