I am in the process of removing and rebedding the toe rail to address a leak. I have read about over-drilling and filling with epoxy/filler. How big should the over-drilled holes be?
I am assuming a pilot hole is best drilled to accept the screw. Is the epoxy flexible enough not to shatter when it is screwed in to?
Is 3M 4200 or 5200 the caulk for this job?
Any pointers on how much caulk to put down and the process of bedding the toe rail in, that will not result in squeezing out all of the caulk would be appreciated.
Thanks for your feedback.
George
Over-Drilling Toe Rail Penetrations
Moderators: Tim Bosma, Tom Elsen
same
Hey there George. I do lot's of overdrilling and filling on a variety of boats, old and new. It's a good way to insure that you NEVER have to deal with deck rot around all of the hardware thats installed at the factory, or afterward. I also have lot's of experience with all of the different caulking compounds/types on the market. IMHO, here's what works the best.
I usually overdrill to twice the fastener hole size to keep from possibly missaligning something and breaking through into new core material, making the overdrilling and filling moot. That is in deck areas with balsa core. On the S2 deck/hull joint, you are going through three layers of stuff [no balsa] as I remember, so that's not an issue. Someone correct me if I'm wrong. The top layer is the solid glass deck lip, then a rather thin layer of fiberglass of the hull followed by a wood strip that is bonded under that, on the inside of the deck lip. The wood strip is actually what the screws are supposed to grab ahold of and they are the weak link in the system. When I installed a new toe rail on my boat last year, probobly 10% of the holes had been stripped at the factory when the rail was installed. The screws wouldn't even back out, there was nothing to back out from! Since you can use the toe rail to drill your pilot holes after overdrilling and filling and there's no balsa involved, a 3'8" bit is enough but use a 1/2" if you choose. For the depth, get a small drill bit or tooth pick and use the old holes as a guide and add about 1/8"-3/16" to that to make sure that the screw is not breaking through into wood when reinstalled. You can set the depth of the bit with masking tape rolled around the bit to form a stop of sorts, but you have to go easy on the pushing. A more foolproof approach is an adjustable stop that can be slid on the bit and locked in place. If you run a strip of 2" tape over the holes before you drill, you can leave it there to do the filling and it helps with cleanup. Before you start poring epoxy, go down below and run a strip or two of 2" tape over the wood rail/hull joint area and really push it down well, don't be lazy. Even if the rail looks intact and solid, the epoxy will probobly find some cracks to flow through and then you have a HUGE mess AND a hole or holes that have to be redone! As in most repair/paint work, good prep is 90-95% of the job. Pure epoxy [no filler or fabric] is pretty flexible when it's cured. It won't crack when you install the new screw in the proper sized hole but it's a good idea to mix in some cabosil or high density filler to make it harder and stronger. Just use enough to thicken the epoxy a little. You want it to be pourable and still fluid enough to fills cracks and small voids. Mix the epoxy in small batches because of the heat generated while it's sitting in a mass in the bottom of a cup. Just pour the holes to level or very slightly less. That way there's almost no sanding to do before the rail goes back on. After the epoxy reaches the gelled state, go ahead and pull the tape on the outside of the rail. This keeps the tape from possibly sticking to the edges of the holes and saves in sanding time. Once everything is hard, just sand it smooth if needed. If there is an abundance of old caulk still on the deck and/or rail, a razor blade type widow scraper is about the best thing I've found for getting it off, before the sanding. BE CAREFUL! It takes lots of force to cut the old stuff off.
Nothing beats 3M 5200 for strength and tenacity but only if you can achieve a good bond to both surfaces. In my long experience, polyruethanes don't stick to anodized or unanodized aluminum as well as good old silicone, even if the West Marine advisor and the manufacturers say they do. 5200 gives you all the time in the world to work. Silicone doesn't wait for anyone, although in cooler temperature, there's plenty of time to work with it. Whatever you choose, make sure to clean the bottom of the toe rail and the deck flange completely with MEK AFTER you have removed as much of the old caulking as possible. That's usually the most time consuming part of the job, and also where a [hopefully] great bond comes from. Don't try to save money on the caulking. Too much is always better than not enough. I put the caulking on the rail, one good bead along the hull edge and then a thick bead [1/2"] from end to end going through the hole centers. This should give you enough to squeeze out on the deck side to pull a bead. If not, just run a very small bead down the rail/deck joint after the screws are tightened and pull a radius with your finger. See below. This is a two person job. One person has to control the unfastened end of the rail to keep from smearing caulk everywhere while the other person does the fastening. Three people is easier even still.
Reinstalling the rail is pretty straight forward. Use the rail as a guide for the new holes by remounting it with a screw about every 4' and then use the rail to START the rest of the pilot holes. Using a 1/4" bit and just breaking the surface of the gelcoat makes the rail center the bit and the new hole. Use a bit that is the approximate size of the shank [NOT the outside of the threads] of the screw to finish drilling the new holes. Of course, you can do this for the holes that you already have screws in too, but you don't have to if you're careful centering the bit. If you do the latter, remember to drill slightly toward the inside of the rail. This will pull the rail into the boat when the screws are installed, making a nice, tight fit. If the holes are outboard of center, the screws will pull the rail out, AWAY from the boat, and there will be a gap between the hull and the vertical edge of the rail, not a good thing. Do the final drilling with the rail removed, again using a depth stop on the bit. Before removing the rail, I run masking tape right up to the bottom edge of the rail on the hull, and to within about 3/16" on the deck. After removing the rail, do the same on it. This way when you screw the rail down the caulk will sqeeze out on the tape, not the boat. Use your finger to pull a nice clean radius of caulk on the deck side. If you don't want a caulk radius on the deck/rail edge, just tape to the edge instead of leaving the gap. Wipe away what comes out on the hull side. After that pull the tape on the deck side joint, pulling back into itself at maybe a 20 dgree angle. This keeps the caulk from wanting to string off the edge of the tape and back onto the deck or rail, which makes a ragged edge. Then pull the tape on the hull side. You can clean up anything with MEK.
Good luck,
Dave
I usually overdrill to twice the fastener hole size to keep from possibly missaligning something and breaking through into new core material, making the overdrilling and filling moot. That is in deck areas with balsa core. On the S2 deck/hull joint, you are going through three layers of stuff [no balsa] as I remember, so that's not an issue. Someone correct me if I'm wrong. The top layer is the solid glass deck lip, then a rather thin layer of fiberglass of the hull followed by a wood strip that is bonded under that, on the inside of the deck lip. The wood strip is actually what the screws are supposed to grab ahold of and they are the weak link in the system. When I installed a new toe rail on my boat last year, probobly 10% of the holes had been stripped at the factory when the rail was installed. The screws wouldn't even back out, there was nothing to back out from! Since you can use the toe rail to drill your pilot holes after overdrilling and filling and there's no balsa involved, a 3'8" bit is enough but use a 1/2" if you choose. For the depth, get a small drill bit or tooth pick and use the old holes as a guide and add about 1/8"-3/16" to that to make sure that the screw is not breaking through into wood when reinstalled. You can set the depth of the bit with masking tape rolled around the bit to form a stop of sorts, but you have to go easy on the pushing. A more foolproof approach is an adjustable stop that can be slid on the bit and locked in place. If you run a strip of 2" tape over the holes before you drill, you can leave it there to do the filling and it helps with cleanup. Before you start poring epoxy, go down below and run a strip or two of 2" tape over the wood rail/hull joint area and really push it down well, don't be lazy. Even if the rail looks intact and solid, the epoxy will probobly find some cracks to flow through and then you have a HUGE mess AND a hole or holes that have to be redone! As in most repair/paint work, good prep is 90-95% of the job. Pure epoxy [no filler or fabric] is pretty flexible when it's cured. It won't crack when you install the new screw in the proper sized hole but it's a good idea to mix in some cabosil or high density filler to make it harder and stronger. Just use enough to thicken the epoxy a little. You want it to be pourable and still fluid enough to fills cracks and small voids. Mix the epoxy in small batches because of the heat generated while it's sitting in a mass in the bottom of a cup. Just pour the holes to level or very slightly less. That way there's almost no sanding to do before the rail goes back on. After the epoxy reaches the gelled state, go ahead and pull the tape on the outside of the rail. This keeps the tape from possibly sticking to the edges of the holes and saves in sanding time. Once everything is hard, just sand it smooth if needed. If there is an abundance of old caulk still on the deck and/or rail, a razor blade type widow scraper is about the best thing I've found for getting it off, before the sanding. BE CAREFUL! It takes lots of force to cut the old stuff off.
Nothing beats 3M 5200 for strength and tenacity but only if you can achieve a good bond to both surfaces. In my long experience, polyruethanes don't stick to anodized or unanodized aluminum as well as good old silicone, even if the West Marine advisor and the manufacturers say they do. 5200 gives you all the time in the world to work. Silicone doesn't wait for anyone, although in cooler temperature, there's plenty of time to work with it. Whatever you choose, make sure to clean the bottom of the toe rail and the deck flange completely with MEK AFTER you have removed as much of the old caulking as possible. That's usually the most time consuming part of the job, and also where a [hopefully] great bond comes from. Don't try to save money on the caulking. Too much is always better than not enough. I put the caulking on the rail, one good bead along the hull edge and then a thick bead [1/2"] from end to end going through the hole centers. This should give you enough to squeeze out on the deck side to pull a bead. If not, just run a very small bead down the rail/deck joint after the screws are tightened and pull a radius with your finger. See below. This is a two person job. One person has to control the unfastened end of the rail to keep from smearing caulk everywhere while the other person does the fastening. Three people is easier even still.
Reinstalling the rail is pretty straight forward. Use the rail as a guide for the new holes by remounting it with a screw about every 4' and then use the rail to START the rest of the pilot holes. Using a 1/4" bit and just breaking the surface of the gelcoat makes the rail center the bit and the new hole. Use a bit that is the approximate size of the shank [NOT the outside of the threads] of the screw to finish drilling the new holes. Of course, you can do this for the holes that you already have screws in too, but you don't have to if you're careful centering the bit. If you do the latter, remember to drill slightly toward the inside of the rail. This will pull the rail into the boat when the screws are installed, making a nice, tight fit. If the holes are outboard of center, the screws will pull the rail out, AWAY from the boat, and there will be a gap between the hull and the vertical edge of the rail, not a good thing. Do the final drilling with the rail removed, again using a depth stop on the bit. Before removing the rail, I run masking tape right up to the bottom edge of the rail on the hull, and to within about 3/16" on the deck. After removing the rail, do the same on it. This way when you screw the rail down the caulk will sqeeze out on the tape, not the boat. Use your finger to pull a nice clean radius of caulk on the deck side. If you don't want a caulk radius on the deck/rail edge, just tape to the edge instead of leaving the gap. Wipe away what comes out on the hull side. After that pull the tape on the deck side joint, pulling back into itself at maybe a 20 dgree angle. This keeps the caulk from wanting to string off the edge of the tape and back onto the deck or rail, which makes a ragged edge. Then pull the tape on the hull side. You can clean up anything with MEK.
Good luck,
Dave
thanks
Tom, like some others on this site I am lax on paying my class dues. I hope that in some small way to be able to make up for it by being of help to other class members. Come spring when my seasonal income picks up I will get paid up.
I have been in almost every aspect of the sailing market. Building, selling, maintainence and now sail making. I haven't made much of a living at it but it's growing. Half of that is because I enjoy my free time too much when I could be doing fun things that earn big $$$$$ like blister repair, replacing rotten balsa core FROM THE INSIDE so that it doesn't show [fun with a capitol F], bottom jobs, etc. I really do enjoy the sail making part but it difinitely pays the worst. High overhead, low profit, but it's very satisfying to make a sail or sails and then go out on the same boat that has been struggling to keep up and have it be up there in the hunt, or way fast. And it's clean!
Thanks for the cudos,
Dave
I have been in almost every aspect of the sailing market. Building, selling, maintainence and now sail making. I haven't made much of a living at it but it's growing. Half of that is because I enjoy my free time too much when I could be doing fun things that earn big $$$$$ like blister repair, replacing rotten balsa core FROM THE INSIDE so that it doesn't show [fun with a capitol F], bottom jobs, etc. I really do enjoy the sail making part but it difinitely pays the worst. High overhead, low profit, but it's very satisfying to make a sail or sails and then go out on the same boat that has been struggling to keep up and have it be up there in the hunt, or way fast. And it's clean!
Thanks for the cudos,
Dave
Dave,
The repair is complete and went well. Re-attaching the rail was the trickiest element of the job. The rail comes off as a straight piece rather than conforming to the hull. We tried dry-fitting it from the bow and the stern only to have it bow up at the apex of the bend, just forward of the cockpit. We eventually tried making the initial attachment at the apex, about the 19th hole in the rail (from the stern) and putting in about six screws in either direction while one person pressured the rail to the boat. The rail laid down perfectly.
We used 3M 4000 and applied it to the toe rail (not to the deck), generously, in three bands from the 90 at the hull deck joint, to the raised center rail and in the inboard channel. All of the caulk stayed in place during the installation. A dollop of caulk was placed on each of the screw holes on the deck. A modest amount of caulk squeezed out. I used a DAP bead radius tool (about $2 at Home Depot) and with careful masking of the boat and rail, produced a factory quality bead.
The over-drilling and filling with the epoxy worked well. It did require a careful touch not to drill too deep but all went well. With all of the pressure of the initial dry fits not a screw budged. This is a testimony to the strength of the epoxy. There was serious leveraged pressure on these screws as we figured out the right path.
Thanks for your detailed guide, it was very helpful.
Anyone that is attempting this repair can feel free to contact me and I will discuss it in more detail.
Regards,
George
The repair is complete and went well. Re-attaching the rail was the trickiest element of the job. The rail comes off as a straight piece rather than conforming to the hull. We tried dry-fitting it from the bow and the stern only to have it bow up at the apex of the bend, just forward of the cockpit. We eventually tried making the initial attachment at the apex, about the 19th hole in the rail (from the stern) and putting in about six screws in either direction while one person pressured the rail to the boat. The rail laid down perfectly.
We used 3M 4000 and applied it to the toe rail (not to the deck), generously, in three bands from the 90 at the hull deck joint, to the raised center rail and in the inboard channel. All of the caulk stayed in place during the installation. A dollop of caulk was placed on each of the screw holes on the deck. A modest amount of caulk squeezed out. I used a DAP bead radius tool (about $2 at Home Depot) and with careful masking of the boat and rail, produced a factory quality bead.
The over-drilling and filling with the epoxy worked well. It did require a careful touch not to drill too deep but all went well. With all of the pressure of the initial dry fits not a screw budged. This is a testimony to the strength of the epoxy. There was serious leveraged pressure on these screws as we figured out the right path.
Thanks for your detailed guide, it was very helpful.
Anyone that is attempting this repair can feel free to contact me and I will discuss it in more detail.
Regards,
George
same
Hey George, I'm glad to here that you got it done and are pleased with the results. You are right about the toe rail wanting to do strange things in the middle, that's why I fasten it down every 3-4' before doing my pilot holes; I know how it fits, what the quirks will be and how to get around them. I didn't bring it up in the original answere to your querry because it kind of explains itself. You do what you have to, however you have to, to get the job done. Starting in the middle is great IF you don't wind up 1 [or more !] mm long on the final end. Then you have another 5-30 minutes of time shortening the rail [depending on what tools you do/don't have] while its mounted on the boat, with metal filings dropping all into the wet caulk and the wet caulk getting all over everything! And, if you are using silicone and it's warm out, forget it. The caulk will be skinned over before you get the rail to fit.
Dave,
Great point about ending up long. We tacked the end down early, after getting the center buttoned down, and noticed we were long before we had too many screws in place. We knocked it back a mm with a wood block and a hammer. Slipped right into place.
It is a bit counter-intuitive that you would go into the original holes and end up long, but that was the case. Maybe if we would have tried 3 to 4 foot spacing it would have worked. With tighter spacing it was a nightmare and looked hopeless starting from either end.
A good one to have behind me.
George
Great point about ending up long. We tacked the end down early, after getting the center buttoned down, and noticed we were long before we had too many screws in place. We knocked it back a mm with a wood block and a hammer. Slipped right into place.
It is a bit counter-intuitive that you would go into the original holes and end up long, but that was the case. Maybe if we would have tried 3 to 4 foot spacing it would have worked. With tighter spacing it was a nightmare and looked hopeless starting from either end.
A good one to have behind me.
George
same
George, there's nothing saying that all of the screw holes were where they should have been from the factory, so it doesn't surprise me that they all didn't go back in the same exact spot! The S2's are well built boats by boat industry standards, better than most. The fact remains that they are production built boats and the folks that put them together are constantly pushed to hurry up and get it done, more than get it done right. That's just the nature of the beast.
Dave
Dave