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Ralph Savarese
10-28-2000, 07:33 PM
Just split the top today what a mess the core wood is just dust . I cut some of the inside laminate out of the engine doors to get an example of what i will be doing to the deck. It was rotted also! I will be replacing it with the honeycomb balsa wood called contourKore from Balteck . I just needed to know what is a better bonding resin for this purpose. Also does anyone know how much balsa and the thickness I would need?
1) I will be flipping the top half over cutting the inside laminate along the outside edges. 2)scraping out all the old balsa .
3)Re coating the backside of the outer laminate with resin
4)Installing the cut to size balsa
5) Coating it with more resin and letting it harden
6) Coating it again with resin and installing inner laminate.
7) Re sealing cut edges with small strips of matt and resin!
Done! Yea Right! What do you guys think all work done from inside.
This honycomb flexible balsa was recomended by Gene D after he cut those hundreds of small squares of plywood !
Ralph

Robert Geoghegan
10-28-2000, 10:16 PM
Ralph,

Use polyester resin for a couple of reasons:
1) Polyester is about $15.00 per gallon vs $80.00 for epoxy resin.
2) You will run into bonding problems if you use epoxy resin and your boat was built with polyester resin. Most boats built 60's 70's and 80's are built with polysester resin.
3) When it comes time to sand the seams, polyester sands much easier than epoxy.

I am in the process of rebuilding the deck on a 28' 1968 Magnum, I did much of the work the same as you have outlined.
Good Luck!

Ralph Savarese
10-29-2000, 07:42 AM
Thanks for the insite any more responces would be helpful in this matter . This is one hell of a prodject!

Tito
10-31-2000, 07:03 AM
Polyester is the way to go, epoxy is not nessesary. There is no short cut or quick fix, you will have to replace the balsa. We have found here in Florida, that heat plays an impotant part in deterioration. When the boat has been covered ( Garaged or even a fabric cover ) balsa usually does not rot.

AGUESS
10-31-2000, 08:07 AM
Ralph,

Use the Baltek balsa. This is the only way to go. The process you describe is correct.

I just did the same thing to my 1966 Classic 18. This takes a lot of time. Take it slow and you will have great results.

Good Luck

Alex.

Forrest
10-31-2000, 09:57 AM
You better check with Baltek for the final word and the correct lamination process using their coring. Polyester resin is in much cheaper, faster, and easier to use than epoxy; however, epoxy resin actually bonds better to old fiberglass than does polyester. Bonding to old work with either product is totally dependent on surface preparation. For that reason, be sure to completely and totally clean the old surface prior to rotary-machine sanding with 24 to 36 grit. The rough grit is necessary for the new resin to "key" into the old surface.

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Forrest

PaulO
10-31-2000, 12:35 PM
Ralph,
Forrest is correct with the bonding. There is a reason that Epoxy resin is soo much more expensive. The truth is that polyester resin only bonds to itself thoroughly when applied wet on wet. Epoxy bonds to itself in the wet on dry as long as any waxy residue is remove with cleaner ( this residue does not always appear. It is due to temp and humidity). This is what is reffered to as secondary bonding. A few more more important points: Epoxy is much stronger when correctly mixed, epoxy cure time can be altered by the use of different "speed" hardeners ( polyester will not cure at all below a certain temp. If you are working in the garage in winter this is a major concern), epoxy is an infinitely better moisture barrier. The negatives of epoxy are the cost, the accurate mixing and the cost.
All this said, if I were doing what you are doing, I would probably go with polyester if I could do it before the real cold weather. I would just prepare any cured surfaces as Forrest describes.
PaulO

CDMA
10-31-2000, 01:09 PM
I used West system for the bonding, fairing, filling, and just about everything on my boat. I used 5 gallons and it was worth every penny. The west system is so easy to use with the measureing pumps and can be used in a wider aray of temperatures.

Chris

Scott Pearson
10-31-2000, 03:37 PM
I used crazy glue...Cheap and man does it dry fast. I glued everything...I didn't have to bolt anything on. Saves alot of time!

(NJ)Scott

GEOO
10-31-2000, 06:10 PM
Ralph, I used epoxy on my repairs do to it's extra strength. Polyester works fine. Make sure all area's to be bonded are completely sanded. All old fiberglass has curing wax on the surface. Resin is expensive at E & B or Boat US. Look for a local Fiberglass supplier. Most resins have a shelf life make sure it hasn't been sitting in the store too long. GEOO

[This message has been edited by GEOO (edited 10-31-2000).]

Scott Pearson
10-31-2000, 08:32 PM
Ralph,
I used all Mahogany Company products. they are located in Mays Landing NJ. There # is (609) 625-8101. They supply all the big boat makers world wide. Sea Ray, Manship, Ocean...etc. etc. They have everything! All types of resin, Glass, Mat, Foam, Balsa...Etc, Etc. They will UPS also. They are a wealth of info too. Good Luck!

(NJ)Scott