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CanChris
08-22-2018, 09:31 AM
I am restoring a 1963 cedar strip runabout and am in the process of stripping all paint below the waterline. The process is going well and I would like some feedback on leaving the residual pigment in the cedar prior to applying West System Epoxy. I have been using a heat gun and scraper to remove the bulk of the paint and then 2 separate applications of paint stripper, scraping after each application. I am no longer lifting any paint out of the cedar and would like to know if I need to sand out the pigment or can epoxy as-is. See attached photos. Thanks for the help!

https://uploads.tapatalk-cdn.com/20180822/0a16a4f026bd08fa968089391ea43389.jpghttps://uploads.tapatalk-cdn.com/20180822/4f228a851e9f3bea9a42ffb7db3d921a.jpg


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jcpout2c
08-22-2018, 09:47 AM
I see no issues leaving the pigment there so long as your are not going for a bright finish like varnish. I would sand with 80-100 grit and prime right over that. The fastener holes however do look like they need some cleanup to get out the loose filler , then re-filled. An awl or pick will make quick work of the loose stuff.

Ian McColgin
08-22-2018, 10:08 AM
I also would sand and seal at this point. You have fastening sickness, possibly a little rot. I would soak the hull with CPES before other finish. WEST will go on over CPES just fine. But if you want to have just thinned epoxy and don't understand what CPES does that others don't, learn from WEST how they suggest you thin their product. It looks like the boat is well dried out and all so simple thinned WEST may well penetrate those black spots adequately to stabilize the situation. I would soak in the CPES or thinned WEST before filling any of the fastening holes. Then fill. Then full force WEST.

G'luck.

wizbang 13
08-22-2018, 10:32 AM
I'd hand sand her with very rough stuff,24.Not to remove wood, but to tooth it up.
I'd coat it with WEST 209, extra slow hardener.
It's just a different tack than CPES .The longer it is wet, the more it will soak in.
Then,the usual...deal with blush, build up coats, polish with a DA, fill with 407 .
One might consider using ospho on the blackened fastenings. BUT, this will add a bunch of time, as you must wash the residue off and re dry the boat.
I've had bad reactions with epoxy/cedar/ospho combinations.Not being a chemist, I dunno what happened. Ospho residue is actually good for paint primers, but it f###s up epoxy bad.
You might consider sheathing the boat with dynel
Once epoxified on the outside, I'd CPES the inside.
bruce

DeniseO30
08-22-2018, 10:39 AM
Hold on! It does not look like a cedar-strip boat to me, it looks more like once upon a time canvas covered boat!

you have any more pictures of this boat?

CanChris
08-22-2018, 10:44 AM
No canvas on here, cedar strip unless I am missing something.

https://uploads.tapatalk-cdn.com/20180822/35b2e2253a39d055922f8494c5075490.jpg


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DeniseO30
08-22-2018, 11:18 AM
No canvas on here, cedar strip unless I am missing something.

https://uploads.tapatalk-cdn.com/20180822/35b2e2253a39d055922f8494c5075490.jpg


Sent from my iPhone using TapatalkPretty! Then she was built that way, how thick are the strips?

CanChris
08-22-2018, 11:28 AM
1/4 inch thick. May have been canvased at one point in time. Any issues with this type of build without putting canvas back on?


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wizbang 13
08-22-2018, 11:59 AM
Wow she looks good on the inside!
Nevermind my suggestion of CPES 'ing the interior.
But I would sheath her with dynel.

DeniseO30
08-22-2018, 12:09 PM
Quarter inch thick planks, probably too thin for a traditional caulking, and too wide ( because of movement) to be covered with fabric that doesn't move itself. Is it a Penn Yan? Boats like this have been covered with fiberglass, ceconite, etc. but the planks can move, will want expand and contract unlike encapsulated strips.

I recently learned, believe it or not, on the Facebook group, how ( back in the day) they used to canvas power boats like this, it was done by setting the aircraft type fabric canvas on a flexible mastic.

Hard set plastic epoxy coating on this type of wood works well enough, but the joints in the wood eventually (but not always) telegraph through the very stable almost solid covering

CanChris
08-22-2018, 02:58 PM
Canadian made boat by small shop. 1963 with original trailer, original outboard, lifevests, oars, and cushions. I have not uncovered anything too exciting yet!


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Jay Greer
08-22-2018, 04:52 PM
What kind of metal are those fastenings?
Jay

wizbang 13
08-22-2018, 05:13 PM
...and do you think or know if it has vertical fastenings inside the planking?

CanChris
08-22-2018, 08:22 PM
Appear to be bronze fasteners. I do not see any vertical fasteners? What should I be looking for?


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Gib Etheridge
08-22-2018, 08:22 PM
Wiz, you drunk? It's only 1/4 inch!

Gib Etheridge
08-22-2018, 08:31 PM
I'm probably the only one here who thinks this way but I'd flip it over and lay on 2 layers of 3/32 cedar veneers then glass it.

wizbang 13
08-22-2018, 08:40 PM
Wiz, you drunk? It's only 1/4 inch!

Not drunk yet. But I could imagine copper wires, not nails with heads, per se. I can also imagine a bunch popping out ,or in,or laying on the surface.The frames look to be close together and in good nick.
Oh I think a few layers of modern cold molded veneers would be great! But it's so much work!
Putting resin only seems to not really achieve anything.
Heck, If the wee fasteners are bronze, skip the ospho I mentioned earlier.
bruce

DeniseO30
08-22-2018, 11:30 PM
I agree and it's way more stable than glass on wood planks
I'm probably the only one here who thinks this way but I'd flip it over and lay on 2 layers of 3/32 cedar veneers then glass it.

Gib Etheridge
08-22-2018, 11:54 PM
[QUOTE=wizbang 13;5656347]
Oh I think a few layers of modern cold molded veneers would be great! But it's so much work!
Putting resin only seems to not really achieve anything.

Not all that much now that the base has been built, and think how durable and leak free it would be. Well worth the effort, especially since the boat is small, according to Gib anyway. :rolleyes:

And I agree that resin only won't achieve much.

jackster
08-23-2018, 04:58 AM
The fastening pattern is, I think, a clue to how it is planked.
With only one fastener at the top of each plank, into the ribs, i'm thinking t&g or possibly ship-lapped?
Also, I can't make out any clinched ends on the inside. Ring-shank nails, maybe ?
And, since all the nails seem to be either flush or slightly below the surface and filled, I think it was originally sheathed/canvased ?
I wonder, too, if the rub rail and spray rail were installed with screws and plugs and put on over the canvas ?

CanChris
08-23-2018, 08:10 AM
Well folks, I appreciate all the help on this. I went investigating his morning and here is what I can tell. Planks are 1 1/8” x 1/4”. There is no evidence of canvas under the spray rail, rub rail, stem cap. They all fit tight to the planking with no play after all these years. Also, no signs of canvas under any of the 3 small skegs that run the length of the boat. I also see to tack marks along the stem from attaching the canvas. So, what would be your recommendations on finishing the boat below the waterline? Is it possible this may have always only have been painted? I have a picture of the boat from a sales flyer and it is clearly varnished about the waterline.

https://uploads.tapatalk-cdn.com/20180823/8a66582bc96ba4c1d4df904e0e8ddcbc.jpghttps://uploads.tapatalk-cdn.com/20180823/c54a969aefd2c5dcf0a5ee4e24819543.jpg


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CanChris
08-23-2018, 08:26 AM
Well, I just spoke to the son of the builder! The boat was originally varnished and then once they would check along the seams they would strip the varnish and sheath them in 10oz fibreglass mat and epoxy. Anything less than 10oz would split but the 10oz would hold together. Any advice on good by down this road?


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wizbang 13
08-23-2018, 08:36 AM
Leaning more to a modern cold molding. Not just the bottom, keel to rail.

jackster
08-23-2018, 09:10 AM
Chris.
I will assume you meant "...I see NO tack marks along the stem ..." not "...I see to tack marks along the stem ..."
Fiberglass mat seems the wrong material to use. It will take more resin and require more fairing then woven cloth of some kind...fiberglass, xynole, dynel.
Usually 6-10 ounce. And, best practice is to hide the bottom/topsides seam under the spray rail and the skegs and stem cap bedded and installed after sheathing.
Since it is 1/4" planking, and possible tongue and grooved(?), I think sanding out all the paint residue is not a good idea. And anything coarser then 100 grit could sand through to the tongue.
just my take on it from about 350 miles east. :)

https://westsysteminternational.com/images/support/Sheathing_guide.pdf

DeniseO30
08-23-2018, 09:32 AM
If it was originally built without Canvas or fiberglass it was probably a Peterborough style strip build.

fiberglass below the waterline is with epoxy can work ok because it bonds to wood and does not need to be mechanically fastened. Sometimes I rub rail is at it where the fiberglass ends. Two layers of 6 oz are better than one layer of 8-10 oz. IMO.

jcpout2c
08-23-2018, 10:20 AM
I love all the good advice, but it is going way above and beyond the original question. So I have to ask, did you take the boat for a test drive prior to starting the restoration? If so how was the hull at keeping the water on the wet side of the hull? It may be over kill to glass, canvas, cold mold or anything else a hull that just needs some love.

If there were only some drips coming through I would stick with your original thoughts of giving her a fresh coat of paint. (Granted after a quick sand, CPES, fill and fare holes and maybe a couple coats of epoxy) Then you can either let her swell up or live with the drips if she will only be out for an occasional afternoon.

However, if the hull was sinking (as in water coming in faster than the pumps can get it out) then we can start discussing the other methods of making her tight. I just have to think that if the original construction was good enough for several decades it should still be good today, assuming all the wood is sound, which it looks like it is.

-JP

CanChris
08-23-2018, 10:46 AM
After talking to the builder this is the advice I was looking for. No leaks, planks and transom are very solid and dry. I am planning to keep her on the trailer, not in the water But would like to be comfortable enough that I can send the kids out for a ride without worrying. I would like to keep this as close to original as possible as I live near Clayton, NY and wouldn’t mind attending some of the shows in the area.

What would your thoughts be on the following:

- CPES or West System w/slow hardener
- fill and fair holes
- 2 coats West System w/medium hardener
- topside prime & paint

My only concern is the eventual cracking of the epoxy without re fibreglass.



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DeniseO30
08-23-2018, 02:07 PM
CPS or any kind of hard epoxy coating is going to prevent the wood from doing what it originally did to have leakproof seems; by swelling ever-so-slightly.

it's also my belief, epoxy would crack without glass,

Lemsteraak
08-23-2018, 02:38 PM
I have an analogy, wood boats are either baskets or bowls. What this means is that if it is a basket, like a lapstrake boat, the hull is designed to flex and here lies her strength. A bowl on the other hand, doesn't flex, so it is a much better candidate for cloth and epoxy. I think the first thing to determine is to address just how much this hull will flex. If she is a basket, then caulking or canvas might be best. If a bowl, then maybe a sheathing is in order. Sometimes the old ways are the best ways.

I think CPES is very good for stabilizing wood and as a nice primer that coating can grip to. Where we run into trouble is if we expect it to do more than that. It will not bring back rotten wood, if the structure is compromised, it needs to be repaired before you continue.

So, my advice, which is worth the paper it is printed on, is to look at the structure first and address that. If the structure is designed to flex then if you sheath it, you will invite problems down the line. My concern is not so much with the hull but the transom, hull joint. Even if you sheath it and have it totally waterproof from the outside. If it flexes it will allow water to enter from the inside and the structure will degrade quickly.

Beautiful boat by the way, well worth the trouble.

jcpout2c
08-23-2018, 02:58 PM
Chris,

I would continue stripping just like you have been to get everything looking like it does in your first post. From there I would clean up any loose filler around the fasteners, then hit any questionable areas with CPES until they stop soaking it up. This would be areas that are miss colored around the fasteners or anywhere end grain is exposed. As Denis mentioned soaking everything in epoxy or CPES will not let the hull perform like original.

I would then fill all the fastener holes with something like Famowood and fare the filler down. Give the entire thing a hand sanding with 80-100 grit, you don't need to get the wood super smooth to have a smooth final paint job, a little "profile" will help the paint stick. I would give her 2-3 coats of Interlux Pre-Coat, sanding with 120 between coats. Then 3 or more coats of Interlux Brightsides Polyurethane sanding with 220 between coats. I am kind of a AkzoNobel fan boy and really any polyurithane and its recommended primer will work. Just don't use a 2 part paint, they cure much harder and will crack for sure. Any planked hull will get some cracking in the coatings, but poly is somewhat flexible and it should be minimal.

I think it is important to remember that a restoration like this will never be as dry or reliable as a new fiberglass boat. But for what it sounds like you want to do and for as good as it sounds like the boat is a cleanup and fresh coat of paint will be just right.

CanChris
08-23-2018, 03:38 PM
The last 2 posts makes the most sense to me. The hull will have some flex to it and it has survived the past 55 years without epoxy and glass. Pre-coat and Brightsides were already my finishes of choice. All nail heads are flush with the hull so no filling. A few screws on the skeg that I will fill. The more I think about it the more I like this approach. I will be keeping the boat on the trailer so it will not be soaking around the clock.

I might as well put this out there. Is there any benefit to using something like Petitt Protect as a barrier coating prior to paint? It is epoxy based but may have have some flex to it ( its after 4:30 so Petitt isn’t answer my calls).


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alphatopher
08-23-2018, 04:25 PM
Looks like a Peterborough, or a knockoff. Have you checked under the seats for a serial number? Cedar ship lap planking, brass clinch nailed, oak gunnels, ash ribs. The planking looks nice and tight so there probably is no need to epoxy. These boat were not meant to be glassed, they were just painted/varnished. Having a very similar boat under restoration right now, I'm in the same situation (glass or no glass). My biggest concern is that glassing only the exterior will only advance the deterioration of the boat by not allowing the cedar to flex. Unless you totally encapsulate, cedar swell is a huge concern.

Please let us know your decision on epoxy.

wizbang 13
08-23-2018, 04:41 PM
Here is a piece of dynel with epoxy,WEST 105 /207. It's a cut out from a deadlite(window) from one of my boats. It's a year old.
https://farm2.staticflickr.com/1897/30357770498_bdf2230733_z_d.jpg
Same piece, bent into a curve. I can wobble it into a figure 8, or wag it around all day.
https://farm2.staticflickr.com/1863/30357775428_5e388387dd_z_d.jpg
It flexes about a thousand times more than wood.
Sheathing with dynel will not stiffen up a boat or add "strength".
It WILL stop leaking, slow down swelling and shrinking, and add a bit of "toughness.

CanChris
08-24-2018, 09:17 AM
I didn’t mention in an earlier post but there were a few questionable ribs that were replaced by the previous owner. All others are solid. Overall the boat is in fair condition and I will keep improving on it year over year. For now I just want to get as much done before the temperature drops and the snow flies.

OK folks here’s my game plan:

- West System 105/209 %3 thinned over any questionable spots. Multiple coats if needed.
- fair/fill
- 3 coats Pre-coat
- 3 coats Brightside

The plus side to this is I can still maintain/repair the boat without grinding out epoxy. It’s taken me 1.5 days to completely strip the hull below the water line and I don’t mind doing that again in a few years if I need too.

Next onto the top sides where I will be going straight to varnish. 4-6 coats of an Interlux product. Still deciding on the finish.


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wizbang 13
08-24-2018, 09:58 AM
I would urge you to use a 2 part epoxy barrier coat rather than the pre coat. (interlux 414/414 or Interlux 2000)
Pre coat is good stuff, but its not epoxy. Once you coat the boat with a non epoxy, any ding ,scratch, fracture... the pre coat is now in the way.
The 404/414 or 2000 can be applied thicker and will harden faster, will sand better .They are made for building up.
With out a sheathing, I think you will get the occasional hairline crack, and the Brightside will happily crack with it.


And don't thin epoxy,even 3 percent.

MN Dave
08-24-2018, 10:55 AM
After talking to the builder this is the advice I was looking for. No leaks, planks and transom are very solid and dry. I am planning to keep her on the trailer, not in the water But would like to be comfortable enough that I can send the kids out for a ride without worrying. I would like to keep this as close to original as possible as I live near Clayton, NY and wouldn’t mind attending some of the shows in the area.

What would your thoughts be on the following:

- CPES or West System w/slow hardener /> - fill and fair holes
- 2 coats West System w/medium hardener /> - topside prime & paint

My only concern is the eventual cracking of the epoxy without re fibreglass.

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You may not need to use cloth because the boat seems to be solid enough as is. If you choose to sheathe, whether it should be fiberglass or Dynel is another debate. (Link1 (http://forum.woodenboat.com/showthread.php?210055-Abrasion-Resistance) Link2 (http://forum.woodenboat.com/showthread.php?6640-Xynole-polyester-cloth)). I would weigh cost and difficulty finding the 'ideal' cloth heavily in the decision. IMHO, anything but mat.

The planking is only 1/4 inch thick, so there should not be a problem with cracking if you sheathe the boat with 6 oz fiberglass cloth or 5oz Dynel. Mat is inexpensive filler for all glass construction. As for resin brands, there is a good, but too old for some of the newer ones test here Link3 (http://www.oneoceankayaks.com/Epoxresl.htm). If the boat does crack without sheathing, you don't have to sand all of the epoxy off when you sheathe it. Since the planking is so thin, Sanding out all of the pigment is not a good idea. If a lot of pigment comes off on a piece of adhesive tape you might have to clean it out.

I would fill and fair using micro-balloons or wood flour to thicken the epoxy. Micro-balloons sand more easily, but I have wood flour, and the increased sanding time doesn't outweigh the trip to the store.

Sanding with sharp 60–80 grit sandpaper will give you the best adhesion according to the Forest Products Laboratory. Link4 (http://javascript<strong></strong>:displayDocumentWithTools('/documnts/fplgtr/fplgtr190/chapter_10.pdf');)

Abrasive planing with grit sizes from 24 to 60 causes surface and subsurface crushing of wood cells. The adhesive industry typically recommends 60–80 grit sanding as acceptable for wood bonding as this equates to 24 to 30 knife marks per inch when planing. Generally, anything above 200 grit fuzzes the wood surface and is not recommended.


CPS or any kind of hard epoxy coating is going to prevent the wood from doing what it originally did to have leakproof seems; by swelling ever-so-slightly.

it's also my belief, epoxy would crack without glass,
This is true, but deosn't apply in this case because the construction does not depend on swelling to seal. When planks absorb water they swell. The swelling of thick planks such as carvel generates enough force to crack fiberglass sheathing. Thin planks are easily constrained by the cloth and will not split the cloth. If you want an example of a thin cedar planks with internal frames and glass cloth on the outside only, link5 (https://adirondack-guide-boat.com/building-wooden-boat/).

Here is a piece of dynel with epoxy,WEST 105 /207. It's a cut out from a deadlite(window) from one of my boats. It's a year old.
<
>
Same piece, bent into a curve. I can wobble it into a figure 8, or wag it around all day.
<
>
It flexes about a thousand times more than wood.
Sheathing with dynel will not stiffen up a boat or add "strength".
It WILL stop leaking, slow down swelling and shrinking, and add a bit of "toughness.
Interesting. This is a comparison, not an argument for or against Dynel: 6oz glass will be similar in all respects but more brittle, and uses so much less resin that it might be lighter. Glass cloth with epoxy will break if you fold too tight while I think that Dynel will take a tighter bend and the resin will crumble before the cloth breaks. I don't see where this makes a lot of difference in a sheathing for this boat. For impact testing, this is the only good visual that I know of; Link6 (http://www.oneoceankayaks.com/Abrasion.htm). (After much googling, Syntex was a brand of UHMWPE fiber like Spectra and Dyneema.)

If you want to know too much about Degradation of Wood Products by Metal Corrosion (https://www.fpl.fs.fed.us/documnts/fplrp/fplrp229.pdf).

BillP
08-25-2018, 01:09 PM
After talking to the builder this is the advice I was looking for. No leaks, planks and transom are very solid and dry. I am planning to keep her on the trailer, not in the water But would like to be comfortable enough that I can send the kids out for a ride without worrying. I would like to keep this as close to original as possible as I live near Clayton, NY and wouldn’t mind attending some of the shows in the area.

What would your thoughts be on the following:

- CPES or West System w/slow hardener
- fill and fair holes
- 2 coats West System w/medium hardener
- topside prime & paint

My only concern is the eventual cracking of the epoxy without re fibreglass.



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There's a good reason your hull lasted this long and it wasn't because of epoxy coatings. My thoughts are to fill deep gouges with epoxy filler and paint (oil based) without epoxy coating. I'd just thin the hexx out of the first 1/2 dozen coats to fill the grain...and in my experience it takes at least that many coats when heavily thinned on soft wood. Every yr or so brush a thin coat on to seal nicks, dings and pinholes. Flexibility and sealing won't be a concern. The boat will be close to original and will last another 75 yrs.

I once inherited a 14' Penn Yan purchased new in the 1950s. It sat under a pole barn for about 30 yrs and was used on fresh water. When I got it the planks adjoining the transom were getting soft about 12" fwd.. This boat had glass and epoxy from the spray rail down and I stripped it to see about repair. What i found was moist wood under the glass at the aft end and soft wood in the keel. The boat was no garage queen and was used enough to have water collect and never enough time to fully dry out. It looked dry but wasn't. I've always thought the glass covering didn't let it evaporate fast enough compared to a painted hull. Here in Florida climes trapping moisture is a death trap for wood.

Also, before endorsing the advertised "penetration" of any thin resin as fact, pour a batch on a newspaper and see how many pages it saturates...or try it on the lightest balsa sheet you can find at the hobby shop.

CanChris
08-25-2018, 02:20 PM
BillP, thanks for the advice. Quick question about the transom to plank seam. I have a very small gap between the transom and one of the planks. What should I use to seal the seam before paint?


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wizbang 13
08-25-2018, 02:22 PM
I recon the boat has lasted because it was used lightly and stored well. Where are all the other ones?

BillP
08-27-2018, 11:42 AM
BillP, thanks for the advice. Quick question about the transom to plank seam. I have a very small gap between the transom and one of the planks. What should I use to seal the seam before paint?


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I would have to see it up close but probably use polysulfide. Two part is the best but not easily sourced. I'm in the south so can't say how it handles cold temps. Some of the old runabout guys use 5200 but in my experience it gets hard as a bowling ball, brittle and cracks after 15-20yrs. Could have been bad batches but both applications were yrs apart on different boats and did the same thing.

DeniseO30
08-27-2018, 04:08 PM
Before trying to caulk between plank and transom I would check into the Fasteners which I assume are screws, good chance they are loose stripped corroded.

If that is the case, I woukd try removing the screws getting caulk under the plank, resetting screws slightly longer because they are in the transom, you can probably use longer screws.

CanChris
08-27-2018, 07:18 PM
That was my plan, 5200 and reset the fasteners.


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