5200 bottom

[rideaubill]

Hi all:

well after a complete summer of rain and cool temps I have stripped all my topside and stained the entire 26ft utility craft of mine, and ready to varnish..as long as the rain stops!!

next peice of business is the bottom. The hull is in quite good condition (double hull) stray cauking here and there, does require some after it is swelled. not soft anywhere but lots of flaking paint.

So after hearing this and hearing that..I come to the pro's...
Do I just strip, prime and paint...and do the swelling etc each year, or is there merit in a 5200 bottom, of an epoxy westsystem bottom.

The boat is a 1959 Andress (built Rockport Ont. Canada) 1000 islands utility.

An suggestions and methods would be so wonderful!!!

Bill

[cameron.d.mm]

Bill,

I don't have any useful advice for you on this subject, but I feel the need to post here anyway. I just drove through Kemptville this evening looking at houses for sale (there is a nice looking one just down the road from you), and my wife and I noticed your boat in the drive way. Her comment was something along the lines of, "Nice boat!".

So, imagine my surprise at sitting down to read the forums and... There it was again! It looks like it is in great shape over all, and I hope you get it up and cruising again soon. Always nice to see Ontario built wooden boats.

Question for you: will you launch it at the Provincial park down the way?

Anyway, sorry to hijack your thread and be a creepy net stalker. All the best with the boat!

[alan white]

Chris Crafts with double bottoms have fore and aft planking over diagonal inner planking, and were built with a cotton cloth bedded in either white lead or paint, I forget. This may be similar to what you've got.
Any case, the popular fix nowadays is replacement of the inner diagonal layer with 1/4 or (in larger sizes like yours, I'd go with 3/8") plywood. This is plastered with #5200 as each bottom plank is screwed back on.
It's wise to stay away from epoxies where bottom planking is concerned. You want it to take up each season, and further, find a spot to store the boat that's not paved or gravelled. Plain dirt is the way to go.
It would be a cinch to cover the bottom with plywood/glass/epoxy and be done with it. However, you may want to keep the hull closer to original, and frankly, the #5200 fix will probably outlast you. if correctly done. Replace any bad bottom planks with Honuras, Luan (Phillipine), or Spanish Cedar.

[rideaubill]

Bill,

I don't have any useful advice for you on this subject, but I feel the need to post here anyway. I just drove through Kemptville this evening looking at houses for sale (there is a nice looking one just down the road from you), and my wife and I noticed your boat in the drive way. Her comment was something along the lines of, "Nice boat!".

So, imagine my surprise at sitting down to read the forums and... There it was again! It looks like it is in great shape over all, and I hope you get it up and cruising again soon. Always nice to see Ontario built wooden boats.

Question for you: will you launch it at the Provincial park down the way?

Anyway, sorry to hijack your thread and be a creepy net stalker. All the best with the boat!

WHAT A STRANGE SMALL WORLD...I KNOW THE HOUSE YOU ARE LOOKING AT..

Will email you from my private account..

[rideaubill]

Chris Crafts with double bottoms have fore and aft planking over diagonal inner planking, and were built with a cotton cloth bedded in either white lead or paint, I forget. This may be similar to what you've got.
Any case, the popular fix nowadays is replacement of the inner diagonal layer with 1/4 or (in larger sizes like yours, I'd go with 3/8") plywood. This is plastered with #5200 as each bottom plank is screwed back on.
It's wise to stay away from epoxies where bottom planking is concerned. You want it to take up each season, and further, find a spot to store the boat that's not paved or gravelled. Plain dirt is the way to go.
It would be a cinch to cover the bottom with plywood/glass/epoxy and be done with it. However, you may want to keep the hull closer to original, and frankly, the #5200 fix will probably outlast you. if correctly done. Replace any bad bottom planks with Honuras, Luan (Phillipine), or Spanish Cedar.

My bottom is actually in quite good condition...maybe I should just scrape, paint and caulk where it doesn't swell properly and call it a day until I have a problem..then go through this drastic nasty process??

[alan white]

Absolutely. My rsponse came from the assumption you meant the bottom was to be redone, based on the terminology, where, when they say, "I think I should #5200 the bottom", it means the big procedure described.
There are seam caulks of polyurethane or polysulphide you can buy that will do the job. If you have leaks that don't swell tight you are bound to have to deal with them eventually, but for now you can caulk. Be sensitive to the fact that the seam compound must remain soft enough to squeeze out when the planks swell, otherwise the swelling planks have nowhere to go and will be ever harder to keep tight later, having crushed edges.
The replacement of an old double bottom is somewhat inevitable given the life expectancy of the canvas membrane, but it can always be put off for a while.

[rideaubill]

Absolutely. My rsponse came from the assumption you meant the bottom was to be redone, based on the terminology, where, when they say, "I think I should #5200 the bottom", it means the big procedure described.
There are seam caulks of polyurethane or polysulphide you can buy that will do the job. If you have leaks that don't swell tight you are bound to have to deal with them eventually, but for now you can caulk. Be sensitive to the fact that the seam compound must remain soft enough to squeeze out when the planks swell, otherwise the swelling planks have nowhere to go and will be ever harder to keep tight later, having crushed edges.
The replacement of an old double bottom is somewhat inevitable given the life expectancy of the canvas membrane, but it can always be put off for a while.

Thanks Alan,
I have dealt with smaller wooden boats many times from dingy's to canoes but this is my first double hull, I hear about westsystem bottoms, 5200 bottoms, so say yah others say nay..just hard to tell what is science, and is witchcraft. I will be using the boat in water for an entire season so likely swelling and sikoflex is good? Stupid question but do you paint then caulk? I would imagine so..Looking to go back to it's original copper bottom. Would I be best to completely strip the hull or just remove anything loose and re paint??

[alan white]

There are lots of formulations, so use one suited to the purpose according to the manufacturer (not witchcraft).
You paint the caulk.
If existing paint is sound, it's more protection at worst. You know its okay if it is as hard to remove as perfect paint. Only you know what degree you should go to, since you can (or have to) stop somewhere, unless doing a total rebuild. Use common sense. Thiunk of short, mid-term, and long term restoration goals, and comprimise accordingly.

[rideaubill]

Thanks!! Existing paint is not bad..I have scrapped so already..do need to do more, however the hull pic I posted is the reality of it..

one more stupid question and I'll leave you be :)
Should I caulk everything and let it squeeze out after swelling ..then paint?
or what is a typical process, I have heard the easiest way to swell the hull is to run water in the bilge?

[PAR]

Have you determined what type of construction method is used on this boat? Is it a double plank or carvel build?

As a rule, epoxy or 5200 bottoms, pretty much insure the next repair on the bottom planking will require replacement. In other words, once you glue those planks down, they're married to that location and removal will damage them beyond repair, not to mention what ever they are glued to.

As a point of note, if you're going to leave the boat in the water for a season or extended amounts of time, then 5200 or other polyurethane base adhesive/sealants wouldn't be a good choice. In these cases you want polysulfide (3M 101 or similar). Polysulfide will generally permit you to remove the planking if repairs need to be made, without damage to the planking or it's contact areas.

A boat is design to keep water out, not hold water in. If you want to find out how strong your planking and other structural elements are fastened, then fill the bilge with water, because it will test the pull out strength of each, as things swell and accept the burden, of hundreds of pounds of water in the bilge.

Run a scraper across ever square inch of bottom. Only then will you know the true condition of the paint.

[rideaubill]

The hull is double planked. I have had a fair bit of water in it at one time, some leaks along some seams and along parts of the keel.

Again I tend to think caulk and paint but not something I have great knowledge in..Do I "test swell" it before going on? Boat has been out of the water 2 years now.

[alan white]

If the hull is double planked, the inner layer should be visible inside the bilge as different from the lay of the outer planks. The planking could be diagonal or offset to the outer layer. You might see the remnants of the cloth sheathing between. It won't be intact.
It's true the #5200 bottom won't come off without destruction, but the method is common and is a value-increaser according to the selling market. I am not saying I disagree with PAR, only that the usage of #5200 is what will keep popping up in ads by professional rebuilders and private sellers as well.
I think I would also go with polysulphide for removal in case of a bad grounding, for example. The repair would be orders of magnitude easier.

[PAR]

5200 bottoms, done by professionals are usually in name only. Even if polyurethane is employed it's usually not 3M. Most are now realizing they need to use polysulfide, possibly after trying to repair 5200 bottoms or seeing 5200 pull right out of the water soaked seams, in long rubbery strings. A reasonable professional, performs work that can receive future repairs as well.

If your boat is leaking, it very probable it's not the seams on a double planked hull. This is where the water is getting in and the rabbit may be in question (which is typically a single plank, not doubled), but the usual suspect is fasteners, not seam goo.

In other words, before you toss a bounce of money and effort at your boat for things it doesn't need, you should have it accessed professionally.