Bedding compound

W

Wigeon

New member
Im doing some bedding and re-bedding. Sikaflex 291 has been recommended and I think I'll give it a try. I thought about 3M 4200, but it's listed as an adhesive and since I'm using fasteners (nuts and bolts) I don't need the the adhesive characteristic. Any thoughts or experiences with Sikaflex 291 or perhaps another product you've found that might work better? My project area will certainly get wet, but will not be submerged. Many thanks in advance. Larry
 
I use 3M sealants, though I've tried others. 3-M seems to work best for me. Just my experience.

I use 5200 when I want to really, really attach something. I also use it when I'm installing a screw in the hull, to give a permanent seal and prevent leakage into the core. It's really cheap at Home Depot.

I used to use 4200 when I wanted to seal something, but it always turns brown when it's out in the sun. And I have a vague memory that some of the Sikaflex line also turns color. So now I use 4000. It stays white, sticks well and is flexible. It's more of a sealant then adhesive.

All of the above can be used above or below the waterline. And Marine Debond removes them all, with a little work.

Boris
 
Butyl tape or silkaflex are both better bedding options than 3M 4200 or 5200. I'd use butyl tape if I were you. Easier to install and clean up after than the other options.
 
I used Sikaflex 291 as the bedding compound for our stainless steel radar arch. It replaced the 4200 that I originally used and leaked. However, the leaking was caused more by the inadequate amount of 4200 used. In any case, no leaks with Sikaflex after 8 years. :thup
 
Use white butyl tape and you will be happy with the results. I have a roll of the tape in a Ziploc bag. It works in your hands like plumbers putty and there is no waste. Also the stuff never hardens, unlike typical bedding compounds. I purchased my roll of butyl tape from sailrite.com and have enough to share with all of my local boating buddy's.
 
3M 4000 is close to the 4200 in bonding and does not yellow as the 4200 and 5200 compounds do.

I want the best adhesion possible with any "bedding" compound. Remember to seal the core, with epoxy, even if you don't have leaks, wet core or rot currently. This is key to maintaining a boat which has any wood cored structure.
 
I used the sikaflex today to mount a davit on a swim platform and at about 47 degrees it was thick and sticky, but flowed nicely. It will take at least 24 hours to cure. Many thanks for your thoughts. Larry
 
Back
Top