Typhoon after deck core material & thickness

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Josh

Typhoon after deck core material & thickness

Post by Josh »

I unfortunately have to replace the core in the after deck of my Typhoon. The best I can figure is that it has 1/4" core material. Any body have any experience with this?



joshuashenker@yahoo.com
Bill Bloxham

Re: Typhoon after deck core material & thickness

Post by Bill Bloxham »

Hi Josh
I used 3/8" Balteck on hull #696, and it fit fine. I did have to replace the top skin due to the PO's use of plywood without sealing deck penetrations, tho.
FYI, it's 3/8" throughout the deck areas.
Good luck
Bill



mmmmmmbill@earthlink.net
Tom

Re: Typhoon after deck core material & thickness

Post by Tom »

I have the same problem... only in a smaller area... is there any reason that I should not just fill up the void with fiberglass and resin?


Josh wrote: I unfortunately have to replace the core in the after deck of my Typhoon. The best I can figure is that it has 1/4" core material. Any body have any experience with this?
Jay B

Re: Typhoon after deck core material & thickness

Post by Jay B »

Josh wrote: I unfortunately have to replace the core in the after deck of my Typhoon. The best I can figure is that it has 1/4" core material. Any body have any experience with this?
I just in the last couple of weeks replaced much of the core in my TY. The balsa core was 3/8" thick. I Replaced the core with cedar, about 1/16" less than the original core to allow foe a fiberglass build-up. After chiseling out the old core, I epoxied in fiberglass to the existing bottom skin then epoxied in the cedar core. Then about alternating cloth and mat to get it close to level with the deck. Then I finished it out with west system fairing filler and epoxy to get it fair with the deck. Looks great now, but was a tedious although fairly easy job. Make sure to grind a good bevel in the top layer of existing glass around the repair so that the new glass can marry up with the old, (basically a scarf joint).

Good luck



Bonahooms@yahoo.com
Joel

Re: Typhoon after deck core material & thickness

Post by Joel »

I just recored the same area and also some of the foredeck. I used 7/16 exterior grade plywood. I cut off and saved the top "skin" and chiseled out the rotten core. Since I wanted to remove all the rotten core, I cut a little beyond where I thought the rot ended. The "non-rotten" core sections were absolutely a bear to remove. I ground away any remaining wood on the inside of the both the lower fiberglass skin and the saved upper skin. I cleaned all surfaces with acetone, epoxied the new plywood core into place, filled the remaining small voids with epoxy mixed with high density filler and epoxied the skin back in place. I pre-drilled oversized holes in the plywood and filled them with high density filler/epoxy where I would need to drill holes for deck fixtures so that this won't happen again. Even though I used thicker wood than other folks reported, I still had areas where my newly installed skin was slightly lower than the original skin. I didn't expect this. I haven't yet faired the surface.

Anyway, it IS a tedious job. The right tools, especially the grinder, made all the difference in the world. I used a rotozip with spiral blade to cut through the aft deck. It took over 1.5 hours and wasted 6 bits. I switched to a cutting disk on the zip mate attachment for the foredeck. That took about 30 minutes. Other than using the right tools, the only other problem was over-analysis. Once I stopped thinking about it and got started, it went pretty quickly.

Good luck

Joel
s/v Pokey II
'73 Ty #549
Bayside, NY



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Joel

Re: Typhoon after deck core material & thickness

Post by Joel »

What is "fairing filler"? I used 404 for filling the voids but didn't see anything in West Marine that was called "fairing filler". How was it to work with? Any tips? Did you have to do much sanding/grinding after you were done?

Thanks for any advice you can give.

Joel
s/v Pokey II
'73 Ty #549
Bayside, NY



bondy_joelNOSPAM@hotmail.com
Bill Bloxham

Re: Upgrading The Crusing Sailboat (Int'l Marine)

Post by Bill Bloxham »

In his book(above) Dan Spurr recommended a circular saw set to 1/8th inch. I did, it went real fast and afterwards I used the blade all that summer to cut 2X4's.
When the blade is set that shallow it is easy to make most corners and curves.
Bill



mmmmmmbill@earthlink.net
Joel

Using a Circular Saw

Post by Joel »

That's what was recommened by Don Casey in his book "Hull and Deck Repair" as well. I rejected it because I had to follow the curve of the toe rail. I didn't think about the fact that when the depth is set so shallow, the length of the blade that will be in the glass will be so short that curves would be easier to handle.

The cutting disk in the Rotozip Zipmate is mounted in a housing that is similar to a circular saw. I was able to set the depth and since the blade itself is so much smaller than a circular saw, I was able to follow the curve of the toe rail very easily.

I also used the Zipmate as my grinder, but a drill would have served equally well. Good thing I didn't buy the Rotozip just for this project!
Rocky

Re: Typhoon after deck core material & thickness

Post by Rocky »

I replaced the entire core of my tyhoon deck. I used a 4" grinder with a diamond blade. Went very fast. It uses 3/8 balsa core. You use a core to seperate the skins and use less weight. To "glue" the skin back use west 406 colloidal silica thickened to the consistency of mayonais and spread with a notched spreader and weight the top skin down well but not enough to concave the skin.



rdins@rof.net
John H

Router Straight Bit

Post by John H »

I did the same project, and cut through the upper skin with a 1/2" Router straight bit, using the combing and aft moulding to guide the router. I set the bit to about 1/32 above the lower skin. Worked great.



Jhalpo@rcn.com
Hobbster

Re: Typhoon after deck core material & thickness

Post by Hobbster »

When I do this type of repair, I go back with balsa. When balsa is installed properly, the core should last. DO NOT use treated plywood. There can be a bonding problem with treated plywood. If you want to use plywood, use Ext. fur. Cut it into squares and place the squares into the void. Dry fit them, number them with a marker, then glass then into place. I built a swim platform for a 40+ foot Hatteras on saturday using this meathod. The owner did not want to wait for me to get in the balsa core material.

By using plywood squares, you will get a better bond and should there be a leak into the core, only one or two squaires will be damaged. I use polyester resin and glass for this type of repair. In fact, I have a rebuilt a TY daysailer that I fixed the cockpit deck core problem as above.

Best of luck,
Glen





glen@hobbymarine.com
Jay Bonahoom

Re: Typhoon after deck core material & thickness

Post by Jay Bonahoom »

Fairing Filler is west system # 410 I used 404 also to fill voids. I think it is called Adhesive filler. But 404 takes a lot of elbow grease to sand. 410 is not structural but works great for your last layer of fill because it sands out easy and to a feather edge. It is pretty easy to work with, buy extra, I used a lot more of it than I thought I would. The only tip I would have would be to not mix up any more than you can put down in a 5-7 minute time period. Once it starts to set up in the can you will have a mess. Other than that it is great stuff.

Joel wrote: What is "fairing filler"? I used 404 for filling the voids but didn't see anything in West Marine that was called "fairing filler". How was it to work with? Any tips? Did you have to do much sanding/grinding after you were done?

Thanks for any advice you can give.

Joel
s/v Pokey II
'73 Ty #549
Bayside, NY


Bonahooms@yahoo.com
Migs
Posts: 24
Joined: Sep 2nd, '20, 13:11
Location: Anabelle

Re: Typhoon after deck core material & thickness

Post by Migs »

Hi Josh,

I realize you've posted about replacing the after deck on your Typhoon back in 2002. How did it go? Am looking at doing the same on my Ty. Any tips aside from the ones I have read above?
Thanks in advance.

Migs
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