Re-bedding stanchions on 2001 Mainship Pilot 34

Jeffg47 · Oct 2, 2016

Hello..The previous owner slathered silicone at the stanchion bases of the deck railing and I would like to clean up the mess and bed them properly. Can anyone tell me how the stanchions are fastened? Are they thru bolted with backing plates? If so, how can the accessed without removing cabinets or liners? Are they simply lagged into the deck? Any input would be great!
Thanks,
Jeff
Cape Cod
Mainship 34 Pilot 2001

ksanders · Oct 2, 2016

They are going to be through bolted

You are going to have to take enough of your interior apart to get to them. :nonono:

I use the old standby (3M 5200 fast cure) simply because it works and I never have to go back and do it again. Any other solution might lead to re-doing the job, but 5200 seals, and things stay sealed. :dance:

BTW although I have a tube of silicone onboard I rarely use it, much prefering 5200. I have not seen a silicone sealing job that lasted long, and I've never seen a 5200 sealing job that didn't last forever.

Bacchus · Oct 2, 2016

compass marine how to has a good article on reversing using butyl tape
I have used butyl tape for bedding and like it...others have also reported good results
A Google search should turn it up

I'm not sure how MS rails are attached... I've seen some reference to just screws into backing but haven't been able to confirm

ksanders · Oct 2, 2016

Bacchus said:
compass marine how to has a good article on reversing using butyl tape
I have used butyl tape for bedding and like it...others have also reported good results

I have heard of folks using Butyl tape but have never seen or used it myself...

So, I am curious... Why would someone choose Butyl tape Vs the other options out there? This is very interesting.

sdowney717 · Oct 2, 2016

Since this is now thoroughly silicone contaminated nothing will stick. You must clean it somehow.
Hull truth forum pointed to this as effective. Never used this myself. I dont use silicone caulks anywhere.
http://www.dsr5.com/siliconeremoval.htm

Debond 2000 mentioned and also never used that either. When I run into trouble, I clean with solvents, dish soap, scrunges, sand and paint.

Bacchus · Oct 2, 2016

ksanders said:
I have heard of folks using Butyl tape but have never seen or used it myself...

So, I am curious... Why would someone choose Butyl tape Vs the other options out there? This is very interesting.

The good quality stuff is tenacious....sticks like crazy... stays flexible...won't squeeze out like other caulks will if tightened too much too early.
Most caulks recommend a 2 step process...snug up...let cure...re tighten.

Bottom line it works and lasts a looking time if done correctly.

Agree if silicone was used prior..you do have to clean w a silicone cleaner

Bacchus · Oct 2, 2016

Can anyone confirm railing attachment method for late model(mid 2000) model yr MS's?

I've heard bolts threaded into plywood backers...bolts & nuts
But haven't been able to confirm either

Comodave · Oct 2, 2016

They butyl tape is surely the way to go. If the silicone is just applied around the edges of the stantion base, it should not be a problem since it will not be under the base. Clean it off and use butyl under the base.

sdowney717 · Oct 2, 2016

Dish soap, scrub it, rinse it using water better than a solvent alone. A solvent might just push the silicone oils around. I have mixed soap and water and scrubbing with alcohol and other solvents (including gasoline) all at the same time with a final water rinse, and it works.

rochepoint · Oct 2, 2016

Here is a link to the Compass Marine bedding article. I use butyl tape and I will also tell you that his Marine "Bed-It" tape is also different than the butyl tape you buy at your local RV store, it has more stick to it & works better. Second best thing is clean up..........just a happy customer!

sdowney717 · Oct 2, 2016

I have used DAP Acrylic latex caulks on screws into wood for stanchion bases.
It is pretty easy, you squirt the caulk into the hole, mush it in with a nail and coat the screws. It cleans up easily.
Never had one leaking. It is the screws you want to seal. Butyl tape costs more. I have used them and they also work.

Last haul out, I cleaned out all the wood plank seams above the waterline and sealed with Dap Dynaflex 230. Worked out perfect. cleans up easily, paint sticks fine. You can't leave it unpainted or it grows mold. The Dap Alex caulk does not seem to grow that mold.

Nomad Willy · Oct 2, 2016

Kevin Sanders wrote;
"They are going to be through bolted"

How did you determine that Kevin? I assume you took them apart and saw that they were indeed through bolted.

When I was faced w the problem I was very worried I'd not be able to access the nuts under the cap rail. Finally I decided to just get on w it and I picked up my drill motor and ziped out the counter sunk straight slot fasteners. Never heard a nut drop. Never found any.
When it came time to reassemble I treated the fasteners like screws and zipped them right back in and they held well. No striped threads or any other undesirable things happened.
The bolts holding the stanchions on my Willard are bolts used as screws. And this is justified if there are enough threads to hold as well as if one used wood screws. But there are two layers of FG laminate that the fastener would/will need to go through. Since the FG is more like metal than wood machine screws seem the best choice of threaded fasteners to use.

The only posibility that they are nutted on the back side is very questionable in that the fasteners wouldn't be accessible ... how would one attach them?

I only have experience w my Willard and have read no recollectable accounts of stanchions being attached by any other method. Does anybody have experience that shows the stanchions attached in ant other way? I suspect that the industry probably universally attaches the stanchions just as Willard did. But what I know is limited to my experience w my Willard. And my assumptions are just assumptions. I'd like to hear from others that have taken out the fasteners.

Bacchus · Oct 2, 2016

Nomad...
My previous '86 Carver Riviera had bolts w nuts for rails & life line stantions. I was able to access many to tighten w a helper above but I haven't been able to see or access any on my MS 34HTtocofirm for sure.

sdowney717 · Oct 2, 2016

Nomad Willy said:
Kevin Sanders wrote;
"They are going to be through bolted"

How did you determine that Kevin? I assume you took them apart and saw that they were indeed through bolted.

When I was faced w the problem I was very worried I'd not be able to access the nuts under the cap rail. Finally I decided to just get on w it and I picked up my drill motor and ziped out the counter sunk straight slot fasteners. Never heard a nut drop. Never found any.
When it came time to reassemble I treated the fasteners like screws and zipped them right back in and they held well. No striped threads or any other undesirable things happened.
The bolts holding the stanchions on my Willard are bolts used as screws. And this is justified if there are enough threads to hold as well as if one used wood screws. But there are two layers of FG laminate that the fastener would/will need to go through. Since the FG is more like metal than wood machine screws seem the best choice of threaded fasteners to use.

The only posibility that they are nutted on the back side is very questionable in that the fasteners wouldn't be accessible ... how would one attach them?

I only have experience w my Willard and have read no recollectable accounts of stanchions being attached by any other method. Does anybody have experience that shows the stanchions attached in ant other way? I suspect that the industry probably universally attaches the stanchions just as Willard did. But what I know is limited to my experience w my Willard. And my assumptions are just assumptions. I'd like to hear from others that have taken out the fasteners.

There exists a thing called a SS Tee nut.
It has prongs that can be driven in and they would hold the nut in place.
SS machine bolts threaded into a thick layered fiberglass hole also hold ok with no backing nut, loads are not large on a single stanchion usually. Machine screws will also hold fine in wood with no nuts, if a tight fit.

porman · Oct 2, 2016

I'm also curious about how the rails are attached. On my 430 one of the aft side rails, behind the boarding gate, has two bolts that will not tighten. The rail is outside the aft head and I don't see any way of accessing it. Of course, if it does have a backing plate and the bolts won't tighten then I have a bigger problem.

DHeckrotte · Oct 2, 2016

It'd be wonderful if you find that the nuts are captive. You'd be living well and/or lucky. I expect that most boats are simply bolted before the interior is installed/finished; cheaper.

I'd have to wonder about the butyl tape for this application. You'd mostly be insistent that the bolts and the bolt holes are watertight; the rest of the bedding would be less interesting (unless you were bedding against wood). You'd have to be confident that the butyl would squeeze tightly around the bolt as the bolt was turned to tighten. I think I'd prefer the gummy mess of 5200 or some other sealant which would ooze into the hole, and up the shank of the bolt, and remain clinging to the bolt.

Lots of chatter elsewhere about using both butyl tape and sealant at this sort of joint. The butyl tape maintains a bit of thickness so that the sealant is not squeezed out and leaving enough cured sealant to absorb flexure.

Bacchus · Oct 2, 2016

If you take a look at the Compass Marine How To you will find the recommendation to counter sink the holes which helps force the butyl tight around the bolts / screws as you tighten.
You can also wind a small piece if the butyl around the shaft towards the head to help seal the hole.
The video is worth viewing even if you choose a caulk as it does have some good practices.
RC at Compass is very thorough and doesn't recommend stuff w/o good testing

Gmarr · Oct 2, 2016

rochepoint said:
Here is a link to the Compass Marine bedding article. I use butyl tape and I will also tell you that his Marine "Bed-It" tape is also different than the butyl tape you buy at your local RV store, it has more stick to it & works better. Second best thing is clean up..........just a happy customer!

Just due to everyone talking about Compass Marines butyl tape, I bought two rolls the day I bought my boat. I know I'll have to Re-bed something someday!!!!

Nomad Willy · Oct 2, 2016

I used SikaFlex under the stanchion bases.
Black of course.

Toolbuddie · Oct 2, 2016

Greetings Jeff,
I have recently made similar repairs to our Mainship. In the General Maintenance section under "Stainless handrail repair" you can see some pictures in post #45. Lots of opinions here, all have merit. Bacchus and Mike have recommended to view the video at Compass Marine that covers bedding on marine vessels. Please do yourself a favor and visit that website. LOTS of excellent information there whether you use the Butyl tape or some other product. I used the "Bed-It" Buyltape and thus far I am a convert. As Bacchus has mentioned the tape is very stretchy. One can stretch the tape and wind it around the screw and the screw head. It WILL squeeze into the voids to seal it. Thescrews on our boat were stainless machine screws with washer and nut below. Ours is not easy to access either. Luckily The two I needed to repair were accessible through an access panel in the salon and the other was in the hanging locker in the master stateroom. See pictures on the thread I mentioned. Wood screws are problematic in fiberglass for several reasons. Primarily they spread the material to create the friction needed to hold the thing. Thiscauses cracking and will eventually show up in your finish of the Gel coat. Hoping a machine screw will somehow hold without the requisite NUT is Ludacris.They are engineered to work with a nut. Expect to find a machine screw with washer andnut below. Forget getting lucky with a blind nut imbedded below. They don't build them to be taken apart by us. Take one out to see what it is. By the way why would you guess the PO added sealant around the stanchions? Do you see water stains inside or have you seen water intrusion? And as mentioned the silicone is probably only on the outside perimeter of the base. Not under it. SO don't stress out over removing all traces of the silicone. Whichever method you use you will only seal UNDER the base. If you are determined to decontaminate the area. Do it prior to removing the stanchions otherwise you will risk smearing silicone on the area you will be trying to seal. DH makes a point about the screw turning and possibly not sealing with the Butyl tape. Hold the screw turn the nut.
Good Luck, Keep us apprised of your progress.
Dave.

Ray · Oct 10, 2016

Our 2004 Mainship Trawler the stanchions had machine screws with backing plates or nuts inbedded in glass below. We had to repair one part of the deck rail which required removing one of the stanchions the machine screws came out and tightened without any problems. Without tearing the boat up we could not have worked with any nuts below.

Ray

Re-bedding stanchions on 2001 Mainship Pilot 34

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