Transom crack

[Minnesota]

It's repair time in the formerly frozen north. My transom has a clean split between boards, about 1/32 to 3/32 inches wide. Varnish is peeling back, and a little blackening along edges. Picture attached (sorry not terribly clear).

I plan to strip, bleach, stain. Then...there seem to be two schools of thought about repair. One is CPES and fill with West epoxy, second is rout out a 1/4" or so slot and epoxy in a fillet/spline. The second makes more sense to me as cleaner and more permanent.

Opinions and advice?

[Thorne]

More info -- what boat design, materials used for transom, thickness/dimensions of same, how long out of water, dry or wet-sailed, etc.

Have you considered using a flexi sealant and seeing if the wood takes up enough to squish some of it back out?

[Minnesota]

Fair enough. 36' JJ Taylor cruiser, 1948. Mahogany transom, 3/4" thick 9' beam at transom. Picture was taken one week out of water in the autumn. Boat goes in seasonally.

Flexi sealant might work. Suggestions for one that would work for varnished transom?

[Bruce Hooke]

One thing to be careful of is how much the crack has opened up over the winter. You don't want to put something solid in there if it is going to try to close up. If necessary you could try to keep the area wet for a while to get it to swell back up, but then you've got to get the immediate area dry again so that you can get glue to stick well.

With that issue out of the way, I think I'd go for a spline since this is a varnished transom. Just make sure there is no metal in there (e.g., drift pins), that you router bit is going to slam into.

[Minnesota]

Bruce-
Yup, I'm concerned about swell, too, which led to the original question. The gap was reasonably stable from time it was hauled out last autumn, to today 5.5 months on blocks. The split is about 7 inches above the waterline and swim platform and therefore doesn't regularly get really wet. Thanks for heads up on drift pins.
So the links on the bottom of this thread leads me to your thread "Transom Troubles (Cracks) (4 pictures) (http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=4106)" from two years ago. Yours was painted and mine is bright, but what did you end up doing on the transom?

[Paul Girouard]

One thing to be careful of is how much the crack has opened up over the winter. You don't want to put something solid in there if it is going to try to close up. If necessary you could try to keep the area wet for a while to get it to swell back up, but then you've got to get the immediate area dry again so that you can get glue to stick well.

With that issue out of the way, I think I'd go for a spline since this is a varnished transom. Just make sure there is no metal in there (e.g., drift pins), that you router bit is going to slam into.

I'm confused as to how he'd get a spline cut made between the two boards that are hung on the boat??

http://www.woodenboatvb.com/vbulletin/upload/attachment.php?attachmentid=191&d=1178329495

And why won't this photo post as a picture ?? :confused:



Are you talking about a "dutch man " ?? A spline , to me , is a thin "ish" piece of material inserted into a couple of groove's , I don't see how a spline could be used in this case.

I'm thinking this is a older boat , when it gets wet it will swell just like it has for 59 years , well unless those planks have been changed , or the boat was not built in 1948.

Maybe some bedding compound with some Mahog. color added?? Then when it swells it will push out what it wants the excess could be pared off and color matched again if needed .

[Paul Girouard]

Thought I'd bump this back up , I'm sure we haven't talked this one fully thru. Bob Smalser, Dave Fleming, Bob Cleek what say ye??

[Bruce Hooke]

Bruce-
Yup, I'm concerned about swell, too, which led to the original question. The gap was reasonably stable from time it was hauled out last autumn, to today 5.5 months on blocks. The split is about 7 inches above the waterline and swim platform and therefore doesn't regularly get really wet. Thanks for heads up on drift pins.
So the links on the bottom of this thread leads me to your thread "Transom Troubles (Cracks) (4 pictures) (http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=4106)" from two years ago. Yours was painted and mine is bright, but what did you end up doing on the transom?

Well...I have to admit that progress has been very slow on our boat. If you look at the last post on that thread you'll get more details on where things stand, but the short answer is that we have yet to fix the transom crack.

Back to your boat: If the gap has remained reasonably stable since last fall then I don't think you need to worry too much about the gap closing up after the boat goes in the water (as long as you mean that it has remained reasonable stable since within a day or two of when it was hauled out, rather than since weeks or months after it was hauled out). Realistically, the wood can be compressed some so you don't need to try to figure out if the crack has opened up be a 1/32" over the winter.

[Bruce Hooke]

I'm confused as to how he'd get a spline cut made between the two boards that are hung on the boat??

Are you talking about a "dutch man " ?? A spline , to me , is a thin "ish" piece of material inserted into a couple of groove's , I don't see how a spline could be used in this case.

Sorry about the confusion. I am using spline in a different sense. What I am talking about doing is routing out a thin grove in the transom along the crack (e.g., a router with a straight bit run across the face of the transom) and then sliding a thin piece of wood, coated with epoxy, into this grove. So, my spline would be horizontal whereas spline as you are using the term would be vertical. It would be ideal if the routed grove could be slightly tapered so that there would be a little clamping action as the spline is shoved into the transom from the outside. However, this could be hard to do (its hard to find a router bit with a slight taper) and is probably not essential.

Aside: I believe "spline" means literally a thin stripped of wood, so a splined joint is a joint made with a spline that fits into groves in the edges of the boards (what you through I was describing), but a "spline" alone is simply a thin strip of wood.

[Bruce Hooke]

Thought I'd bump this back up , I'm sure we haven't talked this one fully thru. Bob Smalser, Dave Fleming, Bob Cleek what say ye??

It would be nice to get the opinion of some of these experts...

[pcford]

Wood is always either shrinking or swelling. How do you know it won't swell close when the moisture content of wood goes up?

Owners freak about stuff like this. Try to swell the wood back with towels etc. I would just redo area as I understand you planned to do. Put in some Slick Seam and see if it closes up. It's a wax that will easily squeeze out.

Wide seams and minor splits like this are not a big deal. Keeping a boat looking good...that's the hard part.

[Dave Fleming]

That ain't no new boat so let it sit in the water for a bit and see just what happens to that crack/split/opening.

Last thing you want to do is rush and fill it with something that could make a mild situation into a real mess.

So many folks get anxious and rush to ****fix**** a supposed problem rather that sitting back and let materials and water do their thing.

[Bruce Hooke]

Just to be clear...I think we'd all agree (wouldn't we?) that something should be done with this crack -- leaving it completely alone is just going to encourage more water to get in there and further lift the varnish and get into the wood and possible create a good environment for rot. Filling the crack with something soft would certainly be a safe intermediate course of action, but if that filler is really soft it seems like it could make it hard to keep the varnish from lifting along the edges of the crack.

It does seem to me that assuming what has been reported by the owner so far on this thread is correct, after the boat had been in the water for the whole summer and was then pulled out of the water, the crack did not significantly open up. So, it seems to me that the "test" of seeing what putting the boat in the water will do has already been done.

[Minnesota]

Thanks, fellas. Sorry to be absent from the discussion...real life interrupts.

Bruce is right. The gap between boards is persistent even when hull is wet. Dry/wet difference is maybe 1/16 to 1/8 inch. I agree, pcford, I don't want to be a freak about this, but again I think Bruce is right. I have some rot already and at a minimum I shouldn't leave a gap open near the water line.

So this is really a question about what you put into a gap that will open and close a little in a broad surface to be varnished. (And to Dave's point, a fix that won't make things worse!)

If this were a painted transom it's no big deal, right? The seam compound squeezes around, the paint cracks, but it stays mostly adhered. But I expect varnish to be more brittle than topsides paint. I worry a little about persistent moisture under the varnish seam, and long term trouble.

I think I'm leaning strongly towards Bruce's suggestion: route it out a little (nice idea about taper/clamp) and adhere a "spline" in place. I know the spline and existing boards will each compress a little, but is there also an adhesive that would have a little give to accept the seasonal open/close in a graceful way under varnish?

And no, I don't care if I need to refresh the varnish seasonally. I just want it to stay put and dry while it's in the water for 5 months (short season here...)

[Bruce Hooke]

One of the problems with this place is that you can't tell how much experience people have. So, I do want to note that both Dave and pcford are either professionals in the field or past professionals, while I am an amateur. I obviously think I have something to contribute to the discussion otherwise I would have kept my mouth shut, but their responses should carry more weight than mine.

1/8" of movement is enough to get a bit worried about how well the wood will do at absorbing the movement if you put something solid like a spline in there.

[nedL]

I didn't comment early on, but will throw in my thougths, which are just what Pat & Dave said. I'd use something that will stay soft (for at least a good bit of time), maybe some mahogany seam compound, do my varnishing and get her back in the water. That transom may be ship lapped, so I personally wouldn't want to be gluing in splines.

[Minnesota]

I have lurked on this forum enough to know that Dave and pcford are professionals, but you are no slouch Bruce.

The professional replacing several split planks is going to look at this and fix it. I'll post pictures of the actual repair.

So I'm still curious because I'm a newbie. If you have a carvel hull finished bright (i.e. a larger version of my transom) what do you use as seam compound to varnish over, and what happens to the varnish seal when the planks move and the compound pushes out?

[Paul Girouard]

#1: So I'm still curious because I'm a newbie. If you have a carvel hull finished bright (i.e. a larger version of my transom) what do you use as seam compound to varnish over,

#2: and what happens to the varnish seal when the planks move and the compound pushes out?


#1:


http://www.jamestowndistributors.com/userportal/woeimages/paints/PET-2005MP.jpg http://www.jamestowndistributors.com/userportal/images/Brands/pettit.gif function viewSection(vID){ var tabObj,sctObj,i,imgSrc,tmpObj; for (i=1;ihttp://www.jamestowndistributors.com/userportal/images/tTechSpecOff.gif (http://javascript<b></b>:viewSection('1');)http://www.jamestowndistributors.com/userportal/images/tVideoInactiveOff.gifhttp://www.jamestowndistributors.com/userportal/images/tProdInfoOn.gif (http://javascript<b></b>:viewSection('3');)http://www.jamestowndistributors.com/userportal/images/tWarrantyOff.gif (http://javascript<b></b>:viewSection('4');)</DIV> http://www.jamestowndistributors.com/userportal/images/tTechSpecOff.gif (http://javascript<b></b>:viewSection('1');)http://www.jamestowndistributors.com/userportal/images/tVideoInactiveOff.gifhttp://www.jamestowndistributors.com/userportal/images/tProdInfoOffHalf.gif (http://javascript<b></b>:viewSection('3');)http://www.jamestowndistributors.com/userportal/images/tLinksOn.gif (http://javascript<b></b>:viewSection('5');)http://www.jamestowndistributors.com/userportal/images/tWarrantyOffHalf.gif (http://javascript<b></b>:viewSection('4');)
2005 Series Bedding Compounds are flexible, semi-paste type, slow oxidizing waterproof compounds for bedding in joints in keel, keelson, stem, sternpost, transom, battens and other hull members. Also for bedding in deck fittings, mouldings and trim around deck houses. May be used on wood, fiberglass, and metal or wherever a waterproof seal is required. Apply by hand or pressure gun or putty knife. Thinning is not normally required. May be painted over after the compound has firmly skinned over. These bedding compounds are also recommended for use as a double planking compound in the construction of double planked hulls where canvas is not used. Apply a liberal coat with a serrated trowel on the inner layer before laying up the outer planking.

BRAND: Pettit Z-Spar Type: Bedding Compound


$27.12 / pt for 1 pt and more $24.93 / pt for 12 pt and more

qty.

PET-2005MP Mahogany Pt
PET-2005MP DOLFINITE BEDDING COMPOUND MAHOGANY PINT ***NO AIR SHIP UN1263***
Color:Mahogany





#2: The varnish cracks, the Dolfinite continues to seal the joint.

Lil spendy , but if you can afford the boat that goes with that transom , you can afford the Dolfinite :rolleyes:


#3 : Link :

http://www.jamestowndistributors.com/userportal/show_product.do?pid=4400&familyName=Dolfinite+Bedding+Compound

[Minnesota]

Paul-
Nice. I'm hoping I can afford the transom and the boat. No doubt the Dolphinite is cheaper than a spline, or a screwed up transom. :D
Thanks for the advice from all.

[mike hanyi]

if there is soft rotted wood it will not hold varnish.
If you did spline it, you could only epoxy the lower side of the spline,and leave the upperside dry, then varnish it up.

this way if it wants to move it can,you eliminated the rot. if everything is glued together then something will give where you dont want to.
Ive seen a beautiful varnished hull built with all the the planks epoxyed together, after a few checks that traveled thru several planks they installed splines to fix the problem. it took several splines and a few years untill the boat settled down.
its got to move.
mike