Hobie Forums
http://www.hobie.com/forums/

Restoring Hulls with Gelcoat -- More questions
http://www.hobie.com/forums/viewtopic.php?f=14&t=45817
Page 1 of 2

Author:  heelcat [ Mon Nov 26, 2012 2:26 pm ]
Post subject:  Restoring Hulls with Gelcoat -- More questions

Project is moving along nicely. I have just finished sanding down my hulls and I'm ready to move on to spraying the gelcoat. Maybe.

There are a couple of spots where I sanded down to the glass. Is it okay just to spray new gelcoat on the glass or do I need to prep the glass somehow? I thought I read in some post that you need to prep the glass but after reading all of those posts things get fuzzy.

Also how much gelcoat will I need to order to completely gelcoat both hulls? I'll order the appropriate thinner and wax based on how much gelcoat I order. Sounds like I need at least 2 gallons for both hulls but I want to only order this once so if you think I should order 3 gallons let me know. I'd rather have extra then end up short.

I think that's it for now. I'm sure I'll be back with more questions the further along I get.

Thanks!

Author:  KarlR [ Mon Nov 26, 2012 4:41 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

You can put the gelcoat right on the glass if the surface is smooth enough. I did that where I had to do some repair work and it stuck fine. Better perhaps than on top of old sanded gelcoat, although that might have been because my glass was fresh and not 100% cured. If you have the texture of the glass mat exposed it might show through the gelcoat. You could either do mulitple layers of gelcoat (sanding between) or do a layer of finishing resin and then sand that and put the gelcoat on top.
One fairly thick (0.02?) layer of gelcoat on two hulls used about 3/4 gallon of gelcoat in my case. Applied with a foam brush. I wasted about 1/3 to 1/4 of that due to resin setting up before I was done applying it. Not sure if spraying would use more or less. Faster application will mean less waste due to premature setup and your coat will be more even which probably means less waste too, but you will have some amount of overspray, so I think it would come out the same.

Author:  jmecky [ Mon Nov 26, 2012 6:14 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Re-gelcoating the whole boat is tough, Have you tried wet sanding with 800+ then buffing. That procedure will make even the cats look good. My 84 looks real nice even after 28 years.

The gel coat will add a lot of weight and work.

Author:  hobieandy [ Mon Nov 26, 2012 8:29 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

heelcat wrote:
. Is it okay just to spray new gelcoat on the glass or do I need to prep the glass somehow?

yes. You can spray right over the glass. Its all the same thing- polyester. Just make sure to rough up the surface and clean well with acetone.

heelcat wrote:
Also how much gelcoat will I need to order to completely gelcoat both hulls?

I did a boat last winter and used 2 gallons of gel and 2 quarts of Duratec Clear Hi-Gloss ADDITIVE which really helps with the finishing. I changed color of the boat and I could have used a little more after sanding and finishing( I had some spots to touch up).

Author:  heelcat [ Tue Nov 27, 2012 7:57 am ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Thanks that answers my question. I'll probably order 2 gallons and an extra quart to be sure.

I'm well past making the decision to merely buff the boat or paint it. I am committed to gelcoat. I enjoy restoration work and usually have a project or two in the garage. I have the space, time, and energy for it.

As I stated I've got both hulls sanded down and some of it is down to glass. I am also changing the color of the hulls from white to blue. Removing the non-skid is a major PITA! A lot of that is right there at the glass in order to get rid of all the texture.

Author:  TiberiusGV [ Sun Dec 02, 2012 10:22 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Please post any comments about the process as you move forward. I am looking to start this process in January.

Also, I would really like to know any information you are referencing while you do this.


Edit: I did just spot your first post on Hull Restoration, but if you have anything else that would be great. Also, what was your reason for wanting to go with gel-coat over pain? I am still at the point where I am considering all my options.

Author:  heelcat [ Mon Dec 03, 2012 8:07 am ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

I'm not really referencing anything in particular. I have done a bunch of searches on this forum and asking questions to get people's experience.

Also check out:
http://w1dm.com/projects/HOTLINE/Hotline.html
for a bunch of old articles on boat repair and restoration specific to hobies.

I've completely sanded down one hull at this point. My only advice is use 60-80 grit paper, don't even bother or think about anything higher. I started with a 100 because I was being cautious but that was really a waste of time. I've probably put in about 8-10 hours of sanding on the one hull alone. Very boring and tedious but it's part of the process.

If you are only thinking about brightening up your hulls and they are white I would strongly urge you to avoid doing gelcoat and look at the many other methods first and using soda blasting for the anti-skid deck.

If you are thinking of changing the color then yes you have a harder decision to make. I can tell you that sanding down the anti-skid is a major PITA but it is necessary if you want to truly change the color of the hull. At least half my time was spent sanding it off. I'll post some pics later so you can take a look.

I chose gelcoat because I wanted to change the color of the hull and I wanted to be able to simply sand and buff any scratches out. Gelcoat is more durable and has better maintenance to it. I expect to wet sand and buff it once a year to restore it to basically new at the start of the season. With paint, scratch repair is a little bit more troublesome and you can easily show the white gelcoat underneath.

I know lots and lots of people will try to tell you to just paint it and there are lots of good reasons. It's definitely much less work, cheaper and there are plenty of really good durable marine paints out there.

I'm a bit of perfectionist and it would drive me insane to think there was a better process out there. Gelcoat is certainly not cheap or easy to work with. I just ordered 2 gals of colored gelcoat, 1 gal of Duratec, and the requisite hardner. I also bought the gelcoat spray gun (which I could sell to you for cheap when I am done) and some other random supplies. Otherwise I have an air compressor and sanding tools in my shop. Total cost was right around $500! And that was with a 20% off coupon that fiberglast.com had during cyber week. Luckily I was literally about to order when I got the coupon. Saved me some good money. That's about a 1/3 of the cost of what I paid for my boat. You also probably have to be more aware of temperatures with gelcoat and I'm having to install a heater in my garage, although that's something I've been wanting to do for a while so the wife isn't that surprised and it isn't that expensive. Northerntool has some good garage heaters for around $100.

I've done a few restoration projects where I barely paid anything for the item itself but spent lots more money just getting the item to look and perform the best. To me it's worth it and I enjoy putting the time in and seeing the finished result. If you don't have the patience, room, or time necessary then I don't recommend doing gelcoat. My hulls will be hanging in my garage/man shack for a good two months by the time I am done and that is just for the gelcoat. It will probably take me about another month to slowly put the boat back together. I hope to be ready for the water by March. Of course I don't have kids and my wife is out of town every week from Monday-Friday. I've also closed my office for the entire week of Christmas so I'll be doing a lot of the work that week as we are staying in town.

As an example of a restoration project I once paid $35 for a 1928 17" Delta Drill Press that had really been put through the ringer at a metal machine shop. It was in sad shape. I completely stripped it apart and rebuilt it, painted it, buffed it and now it is literally in showroom shape and is a gorgeous piece of antique machinery that performs flawlessly. I probably spent around $300-$400 on bringing it back to life but it was worth it. It's the first thing anyone notices when they walk into my garage, apart from the 1970 fully restored Vespa that I have in there that is painted the colors of the Italian/Mexican flag.

My gelcoat arrives tomorrow and I'll probably start spraying next week. I have to drag some new power lines to the garage to handle the 240V heater and the increased amps I'll be pulling with the compressor, vent fan, spot lights, etc. Working with my electrician buddy this week to make that happen by the weekend.

I'll post some pics later this week. Let me know if you have any other questions.

Author:  MBounds [ Mon Dec 03, 2012 2:29 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

heelcat wrote:
I'm having to install a heater in my garage, although that's something I've been wanting to do for a while so the wife isn't that surprised and it isn't that expensive. Northerntool has some good garage heaters for around $100
You realize that you're going to be putting a lot of flammable, noxious vapors in the air when you spray?

Styrene's flash point is 88 degrees.

"Hey, Billy-bob, hold my beer while I flip on the heater, will ya?"

BOOM!
Image

All it will take is a spark - from a switch or a motor starting up (compressor). Be careful and wear appropriate PPE for organic vapors.

Author:  heelcat [ Mon Dec 03, 2012 5:03 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Thanks for the warning. I didn't actually know styrene had such a ridicously low flash point as I've never used it before. Of course acetone is also very volatile. I'm only using a small amount of styrene wax at the end but ill be sure to be extra cautious. I have a full body suit, respirator, chemical gloves and good ventilation so I'm not too worried about. Not my first rodeo with noxious and flammable materials. Although I don't think the hillbilly blew up with a beer. Here in NC it would be moonshine. I've personally lit some on fire just to see how potent it was. Probably around 140-150 proof. Stuff will put you in your place that's for sure.

Author:  Bodhi [ Mon Dec 03, 2012 6:22 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

How do you handle the non skid areas? How do you make the nonskid pattern match on a repair? I sanded and buffed the hulls and they came out better than I thought. What about something like awlgrip isn' t that a paint that really holds up well?

Author:  heelcat [ Mon Dec 03, 2012 8:53 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

A few different ways of handling the non-skid. You can make a mold and then use the mold. I posted a link above to some old hobie articles. Browse through there to find the right issue that goes into detail on making and using a mold. You can also buy a pre-made mold from this company. http://www.masepoxies.com/public/index. ... ew&id=5665

I've visited the site and they had some good instructions on using the mold.

I've decided not to bother with it for now and I'm just going to lay down some other non-skid solution like maybe neoprene but I haven't really looked into it yet. I'll bother with it when I get the boat back together.

Author:  jonh [ Mon Dec 03, 2012 8:56 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Bodhi wrote:
How do you handle the non skid areas? How do you make the nonskid pattern match on a repair? I sanded and buffed the hulls and they came out better than I thought. What about something like awlgrip isn' t that a paint that really holds up well?


Check the Nov 2008 issue http://2010.archive.hobiecat.com/hobieclass/ and a search, here in the forums, this is discussed in several places .

Author:  MBounds [ Mon Dec 03, 2012 9:24 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

heelcat wrote:
Thanks for the warning. I didn't actually know styrene had such a ridicously low flash point as I've never used it before. Of course acetone is also very volatile. I'm only using a small amount of styrene wax at the end but ill be sure to be extra cautious. I have a full body suit, respirator, chemical gloves and good ventilation so I'm not too worried about. Not my first rodeo with noxious and flammable materials.
Styrene is what you use to thin gel coat for spraying, not acetone (you can use acetone, but it leaves more orange peel). Use lots of ventilation and turn the heater off right before you start.

I've had my own experience with "Georgia stump water". They don't call it White Lightnin' for nothing.

Author:  heelcat [ Mon Dec 03, 2012 11:06 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Here's some pics for those that are curious.

Image

Image

Image

Image

If you look closely you can actually still see the non- skid pattern! But running my fingers over it it feels pretty darn smooth. I'm hoping the gelcoat will fill in what's left of the non-skid and level it all out. I'm going to spray a small section as a test and see if it works before committing to the whole topside. If it doesn't ill have to go back to even more sanding.

Btw I'm not using acetone for thinning I'm just using it to wipe down the sanded hulls before I spray. I'm hoping I don't have to thin with styrene at all with the gelcoat gun I bought. Manufacture said I shouldn't t need it. We'll find out soon.

Author:  TiberiusGV [ Tue Dec 04, 2012 9:30 pm ]
Post subject:  Re: Restoring Hulls with Gelcoat -- More questions

Looks great so far. Can't wait to see the progress.

BTW, what spray gun did you buy?

Page 1 of 2 All times are UTC - 8 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/