RIB repair. Hypalon and ?

[Scout 30]

Originally Posted by jcapo

Strange that my 3M 4000 attached rub rail holds fine after 3 years of constant UV exposure and 3M 5200 attached rails fail.

Prep maybe.

Can you elaborate? How did you prep it?

[Emmalina]

Replaced our rub strip last year for a white one as the black always got the boat dirty. The new one was a synthetic rubber mix. Glued it all on with bostik 2402 very good glue that I believe avon have always used.

[jcapo]

Originally Posted by Scout 30

Can you elaborate? How did you prep it?

As I recall, I wiped the rail and tubes with toluene and picked off the loose pieces of the old adhesive. It all came off of the rail but most was still on the tubes. I did not abrade the tubes at all. I did abrade the rail a bit with coarse sandpaper. Wiped it all down with toluene again, let it dry, and then went to work with tape and the 3M 4000.

Before I did the whole rail I did foot at the stern on one tube where the old adhesive had failed completely. A year later the repair was still solid so I did the rest. Most of the rail was still held with the old adhesive but the rail pulled off easily.

[timbenner]

I HAVE AN AVON RIB AS WELL!! JUST FINISHED REFURBING IT, WITH THE RUB RAIL PROBLEM.

I bought 3 cans of 2 - part Hypalon glue to re-attach the rub rail. First cleaned everything with acetone and sanded off the excess glue. Now re-attached - good as new.

My rub rail fell off because of de-flation of the RIB. Don't bother fixing the rub rail, if the dingy has a leak and stays deflated. First fix the leaks, so the dink can remain inflated before bothering with the rub rail. The rub rail needs an inflated dink to hold it in place.

Our dink is in Florida, so a baggy un-inflated dink in 60 degree weather at night, is an over inflated rock hard dink during a 90 degree sunny day!! This is why my previous patches didn't hold! I over inflated it on a cold dark evening, so my patches blew out on a hot sunny day.

Now that I've got the rub rail re-attached and all of the holes patched, I'm careful to govern it's inflation level at noon on a sunny day. If it's hard at that time, leave it alone when it's cold, cloudy and seems deflated, unless you're going to deflate it when hot and sunny. Otherwise, you're going to spring a new leak.

[wannacat]

We mixed the white and black and it looks great! The key is to rough up the surface with sand cloth or whatever , then clean well with either acetone or toluene. The trick will definitely be holding it in place somehow? Maybe 99 mph tape [duck tape]??? For at least 3-4 days.
Good luck!

[skipmac]

Originally Posted by coolboat30

Be careful with the toluene. It's hard on your brain cells.

What brain cells?

[Vasco]

Skipmac,

Here's the best adhesive you can get for hypalon, PVC, whatever. I used to use that pricey hypalon glue that used to last five minutes after you opened the cans. Try this stuff. I used it to glue little parts of my hypalon dink that were coming apart from the fiberglass hull on the bottom. Amazing.

Marinetex RM321K FLEX SET 30G EPOXY ADHESIVE

FlexSet is a non-sagging, non-shrinking, permanently flexible epoxy adhesive. Sandable, paintable and chemical resistant, this flexible epoxy adhesive resists vibration and bending failures. It is an excellent product for bonding, repairing and adhering many difficult to adhere to plastics such as Polyethylene (Starboard, Marine Lumber) PVC, ABS, Lexan, Hypalon, etc. Repairs to fiberglass, wood and metals are also accomplished with FlexSet. FlexSet is packaged in a convenient 30g dispenser assuring a proper mixing ratio.

Apply FlexSet above or below the waterline in wet or dry areas! There are simply too many uses for this remarkable product to list here!

Amazon carries it.

[Capt Gill]

A note about the Poly marine 2 part (perhaps others). Pay attention to the expiry date, it's good for 1 year and they're serious. I didn't and payed a heavy price in time and money.

[skipmac]

Originally Posted by Capt Gill

A note about the Poly marine 2 part (perhaps others). Pay attention to the expiry date, it's good for 1 year and they're serious. I didn't and payed a heavy price in time and money.

Thanks. I had seen mention of this and will pay close attention. Just what I need, use some out of date adhesive and end up doing the job twice.

[Scout 30]

Originally Posted by Vasco

Skipmac,

Here's the best adhesive you can get for hypalon, PVC, whatever. I used to use that pricey hypalon glue that used to last five minutes after you opened the cans. Try this stuff. I used it to glue little parts of my hypalon dink that were coming apart from the fiberglass hull on the bottom. Amazing.

Marinetex RM321K FLEX SET 30G EPOXY ADHESIVE

FlexSet is a non-sagging, non-shrinking, permanently flexible epoxy adhesive. Sandable, paintable and chemical resistant, this flexible epoxy adhesive resists vibration and bending failures. It is an excellent product for bonding, repairing and adhering many difficult to adhere to plastics such as Polyethylene (Starboard, Marine Lumber) PVC, ABS, Lexan, Hypalon, etc. Repairs to fiberglass, wood and metals are also accomplished with FlexSet. FlexSet is packaged in a convenient 30g dispenser assuring a proper mixing ratio.

Apply FlexSet above or below the waterline in wet or dry areas! There are simply too many uses for this remarkable product to list here!

Amazon carries it.

This sounds like it would work but it's quite expensive. I found it at Discount Marine for $16 plus shipping but that's for 4 ounces which looks like that's the only size available. I'm not sure how many you'd need to do the whole rub rail but it would be quite a few. Still, if it works it would be worth it.

[Roy M]

NRS has made several videos on Hypalon repair techniques. I have learned a lot from these well-made and professional quality YouTube episodes:

https://www.youtube.com/watch?v=OncF...EFB933092F9649

[DrDelmas]

I am very happy with the result, otherwise I would not have mentioned it. It was easy to work with since it set as quickly as it did. It repair looks good and the stuff is UV resistant.

[Capt Gill]

Originally Posted by DrDelmas

I am very happy with the result, otherwise I would not have mentioned it. It was easy to work with since it set as quickly as it did. It repair looks good and the stuff is UV resistant.

Would you state what result you're referring to ?

[Jim Cate]

fwiw, UV resistance is not of much concern in this sort of repair. The entire glue join area is behind the thick rubbing strake and is not exposed to UV.

What is crucial is the bond strength, especially if the dinghy is deflated and rolled or otherwise compacted. It is t he stress caused by the small radius bends in the strake that typically breaks down the bond.

Jim

[GordMay]

Greetings and welcome aboard the CF, DrDelmas.

Originally Posted by Capt Gill

Would you state what result you're referring to ?

Probably Post 21.

I just did this repair 6 months ago. I sanded the old glue off and cleaned the dingy with. MEK. Using MARINE GOOP, I applied to a 3 foot section at a time and held for a few minutes and kept repeating till all the rail was attached. The temperature was in the 90's which sped up the curring time. I also masked the area.