1986 Century 6 Meter Restoration

[stanleydan]

Hi Guy's Great forum!

Here is the start of my restore, I am still in the process of cutting and removing the floor, motor mounts and the stringers.

My first question is the transome, Since I am doing the rest of the boat I want to make sure I cover it all. I want to remove the wood and rebuild the transome. My transome measures 2" including fiberglass. It looks like 2 layers of plywood.

Here is my question, Once I cut around the transome and reveal the plywood , will this come out somewhat easily? My fear is that the wood is bonded and I would be left with a very uneven surface to mount the fresh plywood to. The 2" is measured from the back of the transome. From the pictures I have seen it looks like the plywood should pull out and make a good clean surface. What should I expect?

What is the ideal plywood to use to rebuild the new stringers / floor ?

Thanks

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

I am getting ready to order my materials. From the research I have done , It looks like I need 4 types of materials.

1) Poly Urethane Adhesive ( Used to Bond the stringers to the hull before I glass them in)
2) 1.5 oz CSM (used for the first 3 layers of the stringers)
3) 1708 Biaxial Cloth (used for the last 2 layers over the CSM)
4) Fiberglass Resin & Hardener


What is a good brand of Polyurethane to use ?
Is fiberglass resin all the same ? I have used various brands. I was going to look for a source where I could purchase 5 gallons?
Is 1708 Biaxial Cloth all the same as long as its 1708 Biaxial Cloth ?

 

[archbuilder]

Re: 1986 Century 6 Meter Restoration

Welcome to Iboats! A lot of guys on here use PL construction adhesive. I don't think its a polyurethane...but I could be wrong on that. I like West systems 6 ten epoxy for bonding to the hull. Poly won't stick to it, so you have to make sure not to get any on a surface that you are glassing later. There are a few differences in poly, but they basically break down into two groups, waxed and unwaxed (or finish poly and laminating). 95% of what you are doing will require unwaxed. Waxed is for the final coat. The wax causes the top layer of the poly to get hard, in unwaxed poly the top layer stays tacky. If you use waxed and want to add more poly later, you will have to clean it with acetone and grind it. That isn't necessary if you used the unwaxed. This is a pretty good resource which will probably answer a lot of your poly questions. I bought all of my glass and poly from them.

http://www.fiberglasssite.com/servlet/the-68/Fiberglass-Information%2C-and-How/Detail

Good luck with your project, how about some more pics of your project?

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Thanks for the info. Until I cam to this forum I did not realize adhesive was used. I am about 2 weeks away from glassing so I will do my best to read up and get a solid game plan. I have about 4 weeks left until it is too cold to work outside. Now I am racing against the clock.

Process is going good, just finished removing the foam, I am going to clean the hull up this weekend and remove the transom.

Here is where I left off last night.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

When it comes to choosing stringer material what is the best route. My current stringers may have been 1/2" plywood at best. After reading it seemed that 3/4" was more of a standard. I then talked to a guy who said I should consider a 2" wide stringer.

Is there a rule of thumb?

 

[Friscoboater]

Re: 1986 Century 6 Meter Restoration

Use 3/4" for the stringers. Check out my thread on my sea ray and It will help you out.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Thanks,

I have been following your posts ! Great job ! You have built that boat to be far supperior than the condition it was in when it was new. After seeing how my boat was built its no wonder it lasted as long as it did.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Had a fun night chopping / grinding & now itching !

I trimmed the floor within about 1 - 2 inches of the hull. I have just a small overhang left. I am guessing I need to remove as much of the overhang as possable. I did not want to risk putting the blade through the side of the boat so I called it a night.

What is the best way to trim it close ? I was going to insert a 1/4" steel plate under the overhang and use a small cut off wheel to cut the lip.

It sure looks a lot nicer as it gets a little cleaner !

 

[archbuilder]

Re: 1986 Century 6 Meter Restoration

Looks like you are making great progress! I used a small air powered die grinder to cut out stuff like that...very carefully. The nice thing about the air power is it is "variable speed" and you can cut fast or slow depending on how close you are to the hull. Once you have it as close as you are comfortable with you can use a grinder to clean it up. Again I use a air grinder, 5" with 24 grit.....for the same reason. They also run very cool like the electric tools, that being said they are air hogs. If you don't have a good compressor, progress can be really slow. I'm sure some of the HF guys will have some suggestions if air isn't an option for you. keep up the good work!

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Thanks,


It has been a fun project. I have a question about Marine grade plywood. I have asked several local wood dealers and they all say they have it , then they ask what kind I want. I was under the impression that marine grade plywood is treated douglas fur. Is this correct ? The last marina I called told me to check home depot.

If I purchase 3/4" marine grade plywood do I build my stringers out of this as well? When it comes time to build the motor mounts etc, what is the best choice of wood for that ?

Thanks Guys for the help! it's greatly appreciated !

 

[archbuilder]

Re: 1986 Century 6 Meter Restoration

Marine grade has more to do with the number and quality of the wood laminates it is made from. I used it for my deck, it is great to work with. Takes resin really well, doesn't warp and try to crawl off .

Several others have used more typical exterior grade plywood successfully. Most of them around here are yellow pine, I hate dealing with yellow pine. I also don't think it sucks up resin as well.

I have an out board, but used red oak where I needed solid lumber. It seems to weather well when I have seen it exposed outside. I think it has a lot of tannins in it that makes it more weather resistant. The American Plywood Association has a lot of info on the various grades of plywood if you want more info.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Thanks !

Since I am new to this I am not an expert . I was under the impression that fiberglass resin is pretty much standard. Now that I am learing the in's and out I noticed there is Polyester Resin & Epoxy Resin .

I found this Polyester Resin and it comes with hardner , wax etc. Will this work for my application ? I will continue to read up so I know the in's and out's by the time it arrives.

Also , when I laminate the first coat on the stringers I noticed some builders slow down the reaction to let it soak in. How is this done with Polyester resin ? Do you back off the mixing ratio?

This is what I was going to order.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

After reading more I found that Epoxy is used when you are bonding new fiberglass to old fiberglass. Since I am doing a restore this is the case. Should I go with Epoxy over Polyester ?

 

[archbuilder]

Re: 1986 Century 6 Meter Restoration

Stick with unwaxed poly. Epoxy is great stuff, but overkill in my opinion. Make sure your grind the old glass first with a 24 grit disk to clean / roughen the surface. You don't have to grind it a lot, just till you have a clean surface with some "tooth. Then wipe it down with acetone, and you are ready to go. You can slow down the reaction by cutting the amount of MEPK you put in the resin. The resin usually comes with a chart that will tell you how much to use depending on the temperature. I keep a thermometer in my shop that I check before I start mixing. If you follow the chart you should have pretty good luck. If something doesn't want to fire off, you can put a heat lamp on it to get it to kick. I have done that a couple times in the winter.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Made some great progress today. The transome , stringers and floor is out. I count my blessings I did not but the blade through the bottom of the boat. I used a 1/4" piece of steel to protect the hull. I would slide this under the lip and grind down from the top. I will be glad when the grinding is done !

What is the best method to bon the new transome to the existing fiberglass ? I have seen various posts with various methods. My boat had a 350 merc with an alpha 1 outdrive. The transome measured 2" when it was removed. I also noticed is several posts the ideal thickness is 2 1/4" for merc. Is there a tolerence?

 

[mac83]

Re: 1986 Century 6 Meter Restoration

Looks like your making some progress.

 

[archbuilder]

Re: 1986 Century 6 Meter Restoration

Nice work, there is a tolerance, but I'm not sure what it is. Friscoboater talked about it in his rebuild. You might PM him and ask.

 

[stanleydan]

Re: 1986 Century 6 Meter Restoration

Went across the border today to Detroit to pick up my supplies. In Canada my choices are limited. The guy who runs the shop said his recomendation would be to go straight to the 1708 and not bother with the CSM. My origional plan was to use 2 layers of each. Should I stay with the 4 layers ?

Also about bedding the stringers, When I bed them down in the adhesive do I want to keep them off the hull ? say 1/8" to a 1/4" Do people cut the angle on the bottom so the follow the angle of the hull ?

Thanks for all the help guys !

I took a short break Sunday to wash the boat, I wanted to see what was under the 10 years of neglect! Seeing the boat start to clean up was a nice change from the daily - grind - itch - itch - itch !

The second picture is my "saw all" I bent the blade on purpose, I used it to cut out the stringers. The curve would allow the blade to deflect off the hull and allow me to cut the edges of the stringers within 1/2" .

 

[stanleydan]

Stringer Question, Board Vs Plywood

Stringer Question, Board Vs Plywood

I have a friend that has offered me 1" mahogany that would work for my 2 main stringers. Should I take him up on this and use them as my main stringers? The price is right (free) . My 2 main stringers measure 5.5" by 12 ft. I was going to keep them 1" in width. My old stringers were 5/8" plywood (at best). My plan is to increase the ribbing in the bulk head for piece of mind. Since I have then entire boat stripped I wanted to know I did everything I could to make it more robust.

Will the fact that the mahogany is a board and not a plywood have any disadvantages or would I be better off with stringers made from plywood?

Am I being too cautious?

 

[archbuilder]

Re: Stringer Question, Board Vs Plywood

Re: Stringer Question, Board Vs Plywood

That is a nice looking boat by the way, well worth the time. Mahogany sounds good from a rot perspective, but it is really oily, I don't think glass would stick to it very well. It is also pretty tight grain, which would also make getting a good bond harder. I would recommend using plywood, preferably a fir and not a pine. I really like seacast, but it is more expensive....but I'm really happy that I used it on my boat.