Floor Replacement and Hull Repair questions

[30yrnavy]

I have a 1976 Glastron T-156 and I'm replacing the floor. I bought a toe-kick saw to cut the flooring along the hull. It worked great but with my fogged up goggles on rendering me basically blind, I made a very professional looking saw cut about 15" long near the back of the boat where there is a rise in the hull. To repair my screwup I'm considering putting 2-3 layers of fiberglass cloth with 2-3 layers of epoxy resin on the inside. On the outside I plan to put one layer of cloth with a coat or two of epoxy resin. My first question is this: would this be a satisfactory way to make the repair? Or is there a better way to do it. I especially like the idea of putting a layer of cloth on the outside as it would be a constant reminder for me to never again attempt to replace a boat floor. For the flooring I'm using 3/4", 11 layer hardwood plywood which has a very smooth surface. I plan to put two coats of epoxy resin on the bottom side and along the edges and one layer of cloth with two layers of epoxy resin on the top side. My second question is: should I rough up the surface of the plywood a little with some heavy grit sandpaper or leave it as is. I'm trying to complete this job without totally destroying the boat and any advice will be greatly appreciated.

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

Welcome to iBoats and if your Handle reflects true Service to our Country, THANKS!!!!!
As for your repair, it's a pretty simple fix. And your close on how to do it. Your deck though is another matter. the 3/4" Hardwood plywood is not what you should be using. It is for Interior use and the glue is not good enuf for marine use. I'd Highly recommend returning it and using Arauco Plywood from Lowe's. Exterior Glue, Waterproof and very nice stuff. You don't have to use epoxy but if you already have it then go ahead and use it. If not laminatin Polyester resin is what is most commonly used on fiberglass boats. It's what your boat is made out of. You will have to order it. Don't want to use the stuff sold at Lowes or the Auto Supply houses. You'll need about 10 yds of 1.5 oz CSM and 5-10 Gallons of resin and 5 yds of 1708 Biaxial Cloth. This is the most commonly used stuff here on the forum. If you already have your supplies, please post up what you have and we can help you with the application. The cut in the hull, again, is an easy fix, and when done, you won't hardly be able to see it, if at all.

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

Woodonglass: thanks for your response and for recognizing my military service. I retired 10 years ago. I've already purchased the wood and have it mostly cut. I did some research before I bought it. It's called blond hardwood made for exterior use, has 11 equal layers, no knots, smooth on both sides, and doesn't appear to have any gaps between the layers. It cost $39 a sheet at Lowe's whereas marine grade would cost over $80 ordered from a lumber yard. On 26 April 2010 erikgreen wrote a nice article on this forum that pretty much explained the difference between marine grade and regular plywood. I figure the wood I got was close enough to marine considering the difference in cost and that I'd have the plywood well sealed anyway. I'm sure the wood I'm putting in is a much better grade than what was put in the boat 35 years ago. I won't be around for another 35 years anyway! One of the most confusing things I'm facing is which resin to use. Most people say to use epoxy resin as it adheres better to the hull, doesn't require sanding between layers, it's stronger and is better to use for repairs on the hull below the water line. Seems the more reading I do, the more confused I get! I haven't ordered the resin or cloth yet as I still haven't made a firm commitment on what to get or how much. So far I've been told I'd need anywhere from 1 to 10 gallons of resin so I guess maybe I'll go for 5. I've read that a 6 oz. cloth would be good to use with only one layer required for the top of the deck. Seems to be a lot of different products to use and different ways to do the job. I'd like to do the job well enough that I could get 10-15 years out of the boat, if I keep it that long. Besides cost, what is your opinion between using Polyester or Epoxy resin in regards to application and adherence?

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

Here's a drawing of how I recommend building decks...
As i stated before, you boat is made from Poly and Poly sticks to poly great. I also sticks to wood great too, as long as you pre-coat the wood. the wood you bought IS good to use in boats. I thought you had purchased Oak interior cabinet grade ply. My mistake. Before you put the deck down, have you checked the stringers and transom to ensure they are all sound??

Click the pic to Enlarge

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

Actually, I went into Lowe's with the intent of buying the oak because it's a hardwood. They had just received this new wood (made in China!) that looked much better so I purchased it instead. I will accept your professional opinion and use poly resin...the many posts you've made assures me that you must be in the know. Thanks for the drawing. I thought one layer of cloth would be enough as that appears to be all that was on the floor when I took it out. Is CSM matting? I basically will be covering the area of 2 sheets of plywood (top and bottom). Do you think 3 gallons of resin and hardener will be enough or should I purchase 5 gallons just to make sure. I checked the stringers and transom and they appear to be good. The transom feels solid and isn't sagging. I didn't take off the top shell of the boat so I'm leaving the front end as is. Do you recommend that I allow each layer of the poly to dry and then sand it before laying the next? I'm trying to keep the amount of work minimal but yet adequate. It's just going to be my old fishing boat. Thanks for your assistance.

 

[rrumba]

Re: Floor Replacement and Hull Repair questions

hey 30yr, ditto WOG on the service to the USA. I myself am a former puddle pirate as we have been called by our big brother service

tapping with a hammer/rubber mallet and listening for the change in sound is one way to check but the best way to check your transom and stringers will be drilling some core holes and checking for he color and dryness of the wood especially around the transom and low for both. dry light colored wood = good, wet dark or water coming out of the hole = bad. if you are using laminating resin you don't need to sand between layers as it does not have wax in it. the wax is what you would sand off so you would get good adhesion to the new glass work.

others will chime in with more experience than I have.


by the way, what's the chance of some pictures??

 

[Cadwelder]

Re: Floor Replacement and Hull Repair questions

Actually, I went into Lowe's with the intent of buying the oak because it's a hardwood. They had just received this new wood (made in China!) that looked much better so I purchased it instead. I will accept your professional opinion and use poly resin...the many posts you've made assures me that you must be in the know. Thanks for the drawing. I thought one layer of cloth would be enough as that appears to be all that was on the floor when I took it out. Is CSM matting? I basically will be covering the area of 2 sheets of plywood (top and bottom). Do you think 3 gallons of resin and hardener will be enough or should I purchase 5 gallons just to make sure. I checked the stringers and transom and they appear to be good. The transom feels solid and isn't sagging. I didn't take off the top shell of the boat so I'm leaving the front end as is. Do you recommend that I allow each layer of the poly to dry and then sand it before laying the next? I'm trying to keep the amount of work minimal but yet adequate. It's just going to be my old fishing boat. Thanks for your assistance.

Question #1 Yes CSM is matting (Chopped Stand Mat)

Question #2 If you get more than a gallon of resin you'll have to pay the hazard shipping fee so I would strongly recommend getting a five gallon pail. It saves you money in the long run and you'll be assured of having enough.

Question #3 You don't need to do anything between the layers, polyester will not cure out completely unless it's sealed off from the air. Unwaxed resin will remain a bit tacky, so it's ready to accept the next layer. You can do about 3 layers at once if you'd like. You don't want to go more because of the heat build up during the curing process of the resin.

Note: Have everything cut and ready to go before you start mixing your resin as you don't have a lot of time before it starts to "kick" 20 to 30 minutes or so... Also if you're new at this mix in small batches until you get the hang of it. Most new people tend to use to much resin....you only need enough to "wet out" the glass good. Use a good air roller to work out any air bubbles. Good luck.

And as others have already said...I thank you for your service to our GREAT country.

CW

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

CW ^^^^ said it all!!!!

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

I salute all of you who have recognized my service to our country. I appreciate all the great advice I've received in my first attempt (hopefully my last) at replacing a boat floor. The stringers feel hard with no noticeable soft spots. Likewise, the transom appears to be okay too. I hate to tap on it too hard for fear I'll find a bad spot! I hate to think about trying to change it out. I figure the worst that can happen is the motor falls off and the boat sinks. I'll have my life vest on so I should be okay. I've had a heater in the boat with a cover over the boat for the past several days to ensure everything gets dried out as much as possible before I put the new floor in. I'll be getting on eBay over the next couple of days to see what I can find in the way of resins and cloth/mat. I'll try and get a couple of pictures posted over the weekend also. My job is pretty amaturistic compared to some others I've seen but I'm enjoying taking on the task. With 3/4" plywood I figure the floor will be much stronger than it's been for the past several years, at least I hope so!

 

[travelship]

Re: Floor Replacement and Hull Repair questions

Thank you for your service!

I'm going to love this thread! I would be very interested to see any and all pics you have, I will be doing this exact job soon. I'll bet your deck looked like mine.


Where did you cut through the hull? I don't want to do the same, and it looks like the deck is laying right on on the bottom of the hull in some places. I'll be paying attention to your materials lists, too. I wish I was closer to you, I'd help you out just for the practice.

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

View attachment 119348View attachment 119349View attachment 119350travelship: Other than taking pictures I'm not accomplishing much on my project this weekend. I hope the pictures will attach okay as this is my first attempt at posting pictures. My flooring wasn't quite as rotted as yours and I hope your stringers and transom are okay. I cut the flooring out using a 3 3/8" Toe-Kick Saw I purchased at Harbor Freight Tools. It worked great cutting the flooring up close to the edge of the hull. The bottom of the hull rises 2-3 inches beginning about 4 ft. from the back of the boat. This is where I began cutting into the hull. I can't believe I did it but I did. I'm leaving the fiberglass flooring along the sides near the transom as is. It's not worth the effort to try and remove it...at least not to me. I'll trim the new flooring around it and make a filler with thinner plywood if needed. I plan to use three sections of plywood for the flooring. Two equal sizes will go from the front, flush to the kickboard under the dash. They will be squared together in the center of the boat with the sides cut to conform with the curvature of the hull. I plan to use thin cardboard or heavy paper to make an outline of the inside side of the hull, transfer that outline to the plywood and cut it with a jigsaw. The third piece of plywood will go crossways by the transom. I'm also replacing the two cross supports with 1 X 4 oak hardwood after I put a couple coats of resin on them. I'm thinking of covering the area where they attach to the stringers with cloth and resin. I'm considering just using two layers of cloth on the top of the floor along with 2-3layers of poly resin. I've read where some people use only one layer and others apply up to three as mentioned in this thread. I believe 3/4" flooring along with 2 layers of cloth will be plenty strong and will last a long time. One other thing I'm doing. I'm going to fabricate two new kick boards (for lack of correct terminology) that go under the dash. My new ones will be extended all the way to the center of the hull and will be glassed in using cloth to ensure a tight seal so water can't make it into the bottom of the hull from the open bow seats. If everything works as planned there should be no water getting under the floor. All I have to do now is put my plans into practice. I haven't ordered the materials yet. I plan to get 5 gallons of poly resin and enough cloth to lay two layers on the deck and around the edges and also to seal the kick panels. I'll coat the bottom of the plywood 2 coats of resin. If your boat is like mine you'll find a support made of plywood that goes between the stringers just under the area as you step into the bow. Mine was rotted and made from 1/2" plywood. My new one will be made from a 3/4" scrap from my flooring and will also be coated with resin. That's pretty much it in a nutshell. If you were around here I wouldn't refuse your help! Hope this info helps in your deciding on how to do your project. I'm sorta using a mix of various advice from folks. I've found this forum to be very helpful.

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

Pics did not work. The link in my signature will tell you how.

 

[rrumba]

Re: Floor Replacement and Hull Repair questions

hey 30, your pics did not work, at least for me anyway.........

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions



Not sure if these pics will come through or not either. I kept getting lost in the directions Woodonglass provided (the screens didn't pop up the same as in the directions). I'm sure the problem is with me! Anyway, in the 3rd and 4th pics (if you can see them) you can see the small area of flooring on both sides near the rear of the boat that I didn't cut out. I'm not quite sure how to do it as it is very close to the hull. I thought about just leaving it as is. Any suggestions? I'm keeping the boat covered to keep the heat in to dry the floor and also in case it rains I don't want the floor to get wet again. You can also see two sand bags in the front of the boat. I was told by the PO that they help provide ballast. Anyone else doing this?

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

Pics are working. I'd cut the entire deck out using whatever means neccessary. A circular saw always worked for me. If you leave a lip so be it. You can use a grinder to get rid of it later. Is that foam wet? If not you can reuse it if you want. Ballast should not be needed unless your motor is too big for the boat. What HP is it?

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

Pics are working. I'd cut the entire deck out using whatever means neccessary. A circular saw always worked for me. If you leave a lip so be it. You can use a grinder to get rid of it later. Is that foam wet? If not you can reuse it if you want. Ballast should not be needed unless your motor is too big for the boat. What HP is it?

Okay...I guess I'll get in there and do what I can in removing the rest of the deck. The weather is starting to turn for the worst here now (getting cold). I'll have a spot in the garage for it in a couple of weeks. Looking forward to getting it inside. The foam is nice and dry now but I'm contemplating if I want to either replace or add to it. I have a couple spray cans of insulation foam. Would a little of that added to the existing foam work? I'm not sure if it's the right kind of foam or not. The motor is 70 HP and the boat is rated for 80 HP. I'm afraid the boat may flip back on the trailer if I remove the sand bags but I'll know for sure when I remove them in a few days. I don't really want to haul around the extra weight of the bags if I don't have to. I'll see how it handles in the water without them next spring. Am I correct in my thinking that no water should be getting under the deck in the bow? The deck is all fiberglass so the only way I can imagine that it would get wet underneath is from water entering from under the bow seats. That's why I want to seal the kick panels under the dash, to keep any water that may find it's way under the bow seats from making its way under the rest of the deck. What little water finds its way under the deck of the bow I figure I can sponge out. The aft side of the space under the bow seats is open. I guess I should try and seal that side off somehow then I wouldn't have to worry about it. Of course if I did that then I wouldn't know if there was any water entering into that part of the boat. Thanks for your continued advice.

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

IMHO GREAT STUFF spray in foam should never be used in a boat. It is not designed for it and oz for oz it is very expensive compared to other alternatives. I recommend using the pink or blue slab foam sheets from HD or Lowe's. It will never absorb water and can easily be cut into what ever shape required.

You should totally seal your deck, Stem to Stern and Port to Starboard. Every attempt should be made to seal it completely and NOT allow water to penetrate below deck. Any water on the deck should flow to the stern and into the bilge where it can be pumped out or drained when the tube plug is pulled. The previous pic I provided shows how the seal between the deck and the hull should be accomplished all around the sides of the hull in all locations. This is one of the most critical areas of your restoration in my opinion. If you take the top cap off, I recommend putting it back on before you do this final step of tabbing in the deck to the hull just in case you have any hull flexing occuring you can pull her back into shape and get the cap back on before you glass it all back together. Just had an iBoater that had to cut his deck tabbing in order to get the flex out of the hull and get his cap to fit back on the boat. That SUCKS!!!!!!!

 

[Cadwelder]

Re: Floor Replacement and Hull Repair questions

If you take the top cap off, I recommend putting it back on before you do this final step of tabbing in the deck to the hull just in case you have any hull flexing occuring you can pull her back into shape and get the cap back on before you glass it all back together

Heed this warning, gutted hulls do flex if not properly supported, I too speak from experience here. My first restore (many boats ago) looked great, but when I took it to the lake you couldn't steer it to save you a**. Being my first restore I had no clue as to why, until I looked at the boat sitting in the water. You could eyeball the transom as a nice straight line to the water level of the lake and then sight on down to the bow and one side was a good 2" higher than the other (the twisted hull). Wasn't an easy fix....

CW

 

[30yrnavy]

Re: Floor Replacement and Hull Repair questions

I agree that everything should be sealed in all areas to ensure water doesn't get under the deck. I don't understand why Glastron didn't do that during construction. Maybe they didn't want their boats to last over a certain period of time so they could sell more. Thanks for the info on the foam. I'll get some of the foam you suggested and add to the existing foam. What's in there just doesn't seem like enough to float a boat. The way my project might end up I just may need the extra foam! I'm not going to remove the top cap. I'll just do the best I can with it in place. I've thought about the possibility of getting a couple of coolers, removing the lids and sliding them up under the cap and fiberglassing them in place (with the tops sealed around the edges) under the seats. Does this seem farfetched? BTW, has anyone used or have any knowledge of PolyGard resin? It's Hi-Bond, Marine Polyester Resin with MEKP, unwaxed and $140 (including shipping) for 5 gallons. I found it on eBay. It seems to be a good price, especially compared to epoxy resin. I thought I'd check to see if anyone has any working knowledge of it before I ordered it. Thanks for the continued inputs.

 

[Woodonglass]

Re: Floor Replacement and Hull Repair questions

Poly Resin does have a shelf life. I have not heard of or used this resin. If you can contact the seller and get written assurance that their product is Fresh then it would probably be ok to use it. I'm all about saving a buck, but... If it breaks loose in the middle of the lake, I guess I didn't really save to much. It's your call, but I have always had good success with USComposites products. Shipping is not good but quality is excellent. You might check locally with body shops and boat dealers to see if they could give you a lead on a local supplier or at least one closer to help on shipping costs.