Restoration of 1981 C-22 swing keel #10580

Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Interprotect 2000 first coat on, need opinions...

Yesterday I was able to get the first coat of Interprotect 2000 on the bottom. I did a little QA sanding and was satisfied that the bottom and keel pocket were ready. I mixed up one third of a gallon kit, that is 32 oz of the base, 10.6 of the catalyst, and 4.5 oz of the special Interlux thinner for the recommended 10 percent. So that yielded approx 47 oz of activated paint.
First I rolled the keel pocket; not the whole thing, just about 2/3 to 3/4 deep where the roller reached easily and coated nicely without dripping. I also rolled and tipped the keel tunnel and up to the volcano/seacock. This is where I discovered that Interprotect does not really tip well, but that is because it was probably too hot outside and the hull was very warm. The rolled finish is a nice as you need for bottom primer anyway. I used a 4 inch fine polyester foam roller.
Then I rolled out the rest of the entire bottom and was amazed at how much paint I had left in the tray, way too much to throw away. I figured it wasn't enough to do a second coat on the bottom so I made sure the keel and rudder were ready (a little hand sanding just to check and solvent wipe down). I put 3 coats on one side of the keel and 3 coats on one side of the rudder, letting each coat dry to the touch before rolling another.
At this point I still had a pretty good amount of paint (realized I should have just rolled the bottom a second time). So I added some grey epoxy tint to the remaining paint and had enough to roll from the bow to the keel pocket on both sides, the fwd 1/3 of the bottom.
So now I am basically on the fence about using the second gallon at all. If I mix up another 32 oz of base plus 10 oz hardner and thinner today that will give me enough paint to tint about 12 oz of it and finish that light grey 2nd coat, then do an entire 3rd coat in white plus do the other side of the keel and rudder w/ 3 coats of white. After that have 1/3 of the kit left to do the final coat that will need to followed immediately by bottom paint when thumbprint dry.
So the question is, do I skip the second gallon of Interprotect because I am getting my 4 coats from just one kit? Are my coats too light because I am using a fine foam polyester roller instead of 1/8" nap roller? As far as number of barrier coats go, remember I have a coat of epoxy on the bare fiberglass, and 8.9 oz layer of glass, and then a skim coat of resin to fill the weave, so that's 3 to 4 coats of epoxy resin.
By the way, I waited until the Sun was low (around 5 pm) and there was light cloud cover to paint. Even then it was still very difficult to keep a wet edge since the hull was so warm itself. I was painting the keel and rudder after dark but air temp was still 74 ish. This stuff stinks! Wear a mask even painting outside!
 
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Jul 23, 2013
487
1981 Catalina 22 #10330 Bayview, ID
I'd go by the recommendations on the label that say something like "20 mil dry film thickness regardless of how many coats." If you've got that, call 'er good.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
I threw that question out there but I guess I had already made up my mind just to use one gallon. I jumped on chance to exchange that extra gallon of Interprotect 2000 (plus 2 extra quarts of thinners) for store credit at a local Interlux supplier today and got my gallon of Micron CF and 216 Special thinner, paid the difference out of pocket. Better than being stuck with a gallon of barrier coat & 2 quarts of thinner I won't use, $175 worth!

So, I'm confident that I will end up with 4 total coats on the bottom plus 3 each on keel and rudder before bottom paint. Judging by the coverage on Interprotect I may get 4 coats out of the bottom paint, but the viscosity may be very different... regardless I will get the recommended 3 coats.

Stingy, I noticed you didn't put any bottom paint in your keel pocket, any reason? When my boat came out of the water it had bottom paint in the pocket, but only the first 4 inches or so.

I'd go by the recommendations on the label that say something like "20 mil dry film thickness regardless of how many coats." If you've got that, call 'er good.
 
Jul 23, 2013
487
1981 Catalina 22 #10330 Bayview, ID
The picture was taken before I painted the pocket. If I had waited until after, you wouldn't see the scrapes through the barrier coat and the VC 17m bottom paint. Since it's such a dark bottom paint, it would have been so dark in there it would have made for a bad picture, even with flash.

So, yeah, it's painted 100%.
 
Apr 1, 2010
398
Cal 33 and Sea Pearl 21 . Crystal River, FL
quick silly question. how are yall measuring yalls keel pockets? I need to check mine vs the keel but im drawing a blank!
 
Jul 23, 2013
487
1981 Catalina 22 #10330 Bayview, ID
I had to improvise since I don't have either of these...





So I just took a long strip of cardboard the width of the bottom of the trunk and started cutting the width down with scissors a little at a time until I could slide it up to the point that I wanted to measure. Then measure the width of the strip normally.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
quick silly question. how are yall measuring yalls keel pockets? I need to check mine vs the keel but im drawing a blank!
I did the same as Stingy except I used a strip of 3/16" MDF, just running the edge on the stationary belt sander until I got the taper correct. I thought I had a picture of that in here somewhere?
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Yesterday afternoon got cloudy and much cooler, around 71 vs the 85 from Monday afternoon. It seemed like it was threatening rain in the evening so I decided to mix a batch of Interprotect small enough just to tint grey and paint the remaining 2/3 of the hull which finished off the overall 2nd coat. I went 12 oz of base, 4 oz hardener and 1.5 oz thinner, just about 18 oz of total paint.
Interprotect 2000 does not need sanding between coats, but just to take care of any inclusions (bugs, bird droppings, or stray roller marks) I went over most of the hull very lightly with 150 grit on a short sanding board. I got the second coat completed and had a little left over to get one coat on the 2nd half of the keel.

I pulled the hull back into the shop in case it rained and to avoid anymore bird sh!t..

Bottom barrier Coat .jpg
 
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Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Stingy, if you want a tool just like pic #1, but waaaaay cheaper go to an art supply store and look in the ceramics and pottery section. They use a tool exactly like these inside/outside calipers for cutting clay while spinning on a pottery wheel, they come in various sizes. Sometimes the axis rivet is horrible and loose so just drill it out and use a small bolt, washer, & wing-nut.

I had to improvise since I don't have either of these...





So I just took a long strip of cardboard the width of the bottom of the trunk and started cutting the width down with scissors a little at a time until I could slide it up to the point that I wanted to measure. Then measure the width of the strip normally.
 
Jul 23, 2013
487
1981 Catalina 22 #10330 Bayview, ID
Thanks for the art supply store tip.

Just revisited your post about rebuilding the motor mount. Did you figure out your bushings? On mine, the thinner flanged ones go next to the latch arms and compensate for their thickness.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Thanks for the art supply store tip.

Just revisited your post about rebuilding the motor mount. Did you figure out your bushings? On mine, the thinner flanged ones go next to the latch arms and compensate for their thickness.
I checked the original plastic bushings I had removed and they were all uniform thickness, so I returned the 5 thin flange bushings Garhauer had sent and requested exchange for the thicker flange, now all 10 bushings have the same flange. I just got them in the mail yesterday right after I read your post. I should get it all but back together this weekend.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Last night I put on the last 'regular' coat of Interprotect. There is actually one more coat which goes on just prior to the bottom paint. The bottom paint goes on as soon as that coat is 'thumb-print dry'.

Right now I am scratching my head on that one. When I rolled that coat on last night it was basically getting dark and was dark by the time I was done and the weather was cool. By the time I was done it was touch dry already, but I didn't put enough pressure on my finger to try to make a print. Anyway, this concerns me.
 
Dec 11, 2008
1,338
catalina C27 stillwater
I have found sometimes that cooler temps will dry finish quicker. I just scratch my head too but know it to be true having witnessed it too many times. I Probably wouldn't be too concerned personally
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
My turn to eat crow!

Well, forget everything I said about only using one gallon of Interprotect 2000... I did get the four coats needed on the hull and 3 coats on the keel and rudder from the one gallon. But, and this is a big BUT, I was wondering why it was curing so quickly, even when painting in cool temps and in the dark.
Suddenly, light bulb pops up over my grape... I've been using high density foam rollers. Duh, they put on a very fine coat of paint. The finish is great and no need to tip each coat, but the film thickness is much less. I bounced this off the Interlux tech reps (3 of them, lol). Using the foam rollers is fine but I'd need 7 or 8 coats, and then another pre-bottom paint coat need to be with 1/4 inch nap regardless to be thick enough not to cure before I roll on the first coat of bottom paint.

SO... Stingy Sailor pointed it out first, yes it does take TWO GALLONS of Interprotect 2000 to do the hull of a C-22. So I had to eat crow and go buy back the kit I had just returned on Tuesday!

STINGY SAILOR
:theman:
 
Jul 23, 2013
487
1981 Catalina 22 #10330 Bayview, ID
At least you figured it out before you put on the bottom paint. That would have been a forehead slapper.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Saturday I got 3 more coats of Interprotect 2000 done, plus the boot stripe is primed with the same but tinted grey (two brushed on coats, so its thick). I did a light hand sand between coat just to get rid of bugs or inclusions. This time I used a medium nap roller that put down a lot more paint.

Bottom Primer.jpg
 
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Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
And finally the bottom paint! I did a hand sand using 100 grit pads for the palm sander. I put a stack of three in my hand so I could keep a grip and went over the whole hull, it helped knock down the texture from the previous rollers and get rid of any flaws, same as before there bugs here and there and a hair or two. I put on the last coat of Interprotect as a tie coat and when it was thumb print dry I rolled on the Micron CF.

Paint bottom paint first coat.jpg
 
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Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
You can see how I have my keel hanging on the hoists in the foreground of the last pic. I did put on another coat of Interprotect but I still have 2 to go. I'm going to hold off on finishing the keel until the hull is flipped back over and on the regular stands. I want to test fit the keel and make sure I have my spacers sorted out and epoxied on before I complete the painting. I have a feeling I will need to mill down the inside faces of my keel hangers just a bit.
I have a bout a quart of Interprotect left, this is just enough to put the last two coats on the keel, the rudder needs only one side done, and I will put one more coat and the tie coat in the keel pocket after it it is flipped back over.
 
Sep 8, 2014
2,551
Catalina 22 Swing Keel San Diego
Last night I cut the compression/spacer tubes from stainless tubing and did a test assemble on the motor mount. Seems everything is about right but I'm short a couple of fender washers for the handle. I have various 3/8 washers in of different thickness to make sure all the spacing is correct before I tighten down the nuts and set the spring.

Engine Bracket Reassembled.jpg
 
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