SC 20 restore part 2

Technical discussion of ARC products
Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

SC 20 restore part 2

Post by Mac M »

I sold my first 20 and regretted it, so a while later I finally got another one. I was only able to sail it a handful of times before it was time to bring it home. I knew I was going to have to tension the dolphin striker cable, but ended up finding one of the bow tangs had started coming loose. This is usually an indication of rotten bulkheads. I had to do the same repair on my first 20, so at least I knew what I was in for.

I ordered new composite bulkheads and deck lids from Tom and got started on the work Friday after work. The repair is going much faster this time! So far I have gotten both of the old ones out, the inside of both hulls prepped, both fitted, and the first layer of glass on one. I'm using epoxy with colloidal silica mixed in for the bonding. Here's picture of one of the bulkheads fitted in and ready for bonding.

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GeneHacker
Hot Shot
Posts: 28
Joined: October 1st, 2013, 3:06 pm
Boat Make/Model: SuperCat 20

Re: SC 20 restore part 2

Post by GeneHacker »

It sounds like this is one of the most common issues with the supercat 20s so its very helpful to see how to do the repair. How is the cover plate attached? How do you remove it?...can you just pry it off?

At this point my 1980 SC20 seems to be good but I tend to be pretty hard on my toys so I can envision having to do this repair in the future.
Kevin Keller
Professional
Posts: 362
Joined: September 24th, 2006, 2:56 am
Boat Make/Model: SC-20, ARC22
Location: Honolulu

Re: SC 20 restore part 2

Post by Kevin Keller »

I've been told it was mainly done because the original SC20's had plywood forward bulkheads. The plywood would eventually rot. At some point they put a fiberglass bulkhead in instead.
Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

This is the second time I've had to do this repair on a 20. Those plywood bulkheads rot after all these years. Tom sells a nice composite replacement and caps to replace the ones you have to cut out. I'll be replacing the caps in the next week and will post photos.

Gene. I removed the cover plates with a dermal tool with a cut off wheel on it. You go back about an inch from the glue line and cut around the cap. Once it was out I went back with a grinder and removed the material up to the glue line. If you carefully do it you will leave a 'shelf' that the new cap can sit. You can see the shelf in the picture above. You ca see a little more detail of the repair in my thread from the other redo viewtopic.php?f=3&t=600
Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Got one of the lids back on yesterday. Not my prettiest work, but that's what sanding and fairing are for! Next up is stripe removal and a small amount (hopefully) of body work.

These repairs have sparked a big upgrade for the old boat. As a result I'll soon have some stuff for sale from the boat including a couple sets of sails (one really nice set that is only about 5 years old), a jib, and possibly a nice Sunrise tramp. I'll post an ad soon when I start ordering new stuff. Just a heads up.....

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Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Removed the stripes, put on the other lid, and fixed a couple dings today. Removing 30 year old decals sucks. Tried a hair dryer, then a 3m decal remover wheel, then acetone, and finally settled on MEK and a razor scraper. Time consuming but they are off. The job looked to be a back breaker so I applied a little redneck ingenuity and got the boat in a more comfortable position for the work.

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Kevin Keller
Professional
Posts: 362
Joined: September 24th, 2006, 2:56 am
Boat Make/Model: SC-20, ARC22
Location: Honolulu

Re: SC 20 restore part 2

Post by Kevin Keller »

Wish I had a work area like that!
fjviola
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Posts: 90
Joined: April 21st, 2011, 7:06 am
Boat Make/Model: ARC 21 and Supercat 17
Location: Seabrook, TX
Contact:

Re: SC 20 restore part 2

Post by fjviola »

Mac
Thanks for all the restoration details and photos. You are a great ambassador!
franklin
Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Pulled the front beam today. This boat was in saltwater only for all of its life until I got it. Those 8 bolts were not fun to remove. Used a can of PB Blaster and took about 2hrs!


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Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

I'm pretty deep into the upgrade now. I got the material for solid beams and a good friend was gracious enough to do the machine work for me. I couldn't find anywhere close by that did anodizing so I had the beams powder coated by a place I do a lot of sandblasting for. They didn't turn out like I had hoped, but they look OK. My self tacking stuff came in so I was able to mount that this weekend. I also got the rear beam drilled and the backing plate for the main traveler tapped. I'm not looking forward to getting that 9ft backing plate attached inside the beam. Any tips are welcome on that one!

After the main traveler I've got to paint the boat, get the spin pole sorted out, and hopefully get some sails coming.

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Kevin Keller
Professional
Posts: 362
Joined: September 24th, 2006, 2:56 am
Boat Make/Model: SC-20, ARC22
Location: Honolulu

Re: SC 20 restore part 2

Post by Kevin Keller »

Mac,

It's not that hard. I wrote this in my post:

"After getting that finished I put a 1/4" by 1/2" piece of aluminum bar inside of the rear beam and drilled holes to mount the solid traveler track. I used a transfer punch to locate the holes exactly, drilled through with the correct tap drill and pulled out the bar. I tapped the bar, enlarged the holes in the beam, reinstalled the bar, and then screwed in the track. Since the beam is 4" diameter I used a 4 1/2" piece of ABS pipe to get the port end of the beams to fit in the 4 1/2 saddle. I cut the ABS on one side lengthwise to get it on to the beam and allow the beam to be compressed."


Get some transfer punches and first mark and drill the 4" beam. You should anchor each end with a screw though so it doesn't shift. Then do the same with the backing piece remembering to anchor the ends again. Make sure you use the correct size drill for the holes. The holes in the backing piece need to be sized for your threads. You can oversize the 4" beam a little to allow a little tolerance.

Looking nice.

Kevin
Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Got it primed yesterday and top coated today. I think most of the hard stuff is done now!

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Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Got the beams bolted down tight today. I've also gotten the spin pole socket mounted and the spin pole fitted up. Everything is fitting up like it's supposed to so far. Waiting on a couple things right now so I took the opportunity to put a set of cat trax together as well.

Tramp should be coming pretty soon so that's the next project.

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Mac M
Professional
Posts: 232
Joined: June 13th, 2012, 5:05 am
Boat Make/Model: SC17
Location: Lugoff, SC

Re: SC 20 restore part 2

Post by Mac M »

Pictures aren't uploading right from photobucket for some reason, sorry
GeneHacker
Hot Shot
Posts: 28
Joined: October 1st, 2013, 3:06 pm
Boat Make/Model: SuperCat 20

Re: SC 20 restore part 2

Post by GeneHacker »

Really impressive. She is going to be beautiful.
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