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Kent Perroux
03-17-2002, 03:53 PM
Well, now I remember why you pay so much for fiberglas work. I am itching all over.

Completely removed the transom wood, getting ready to gelcoat and fiberglass. Then build the new transom. Stringers are going to get strengthened while I am at it. That 502 keeps looking more tempting.

Ripped out all the wiring and just bought all new Gaffrigs so I might be selling my Donzi Gauge package soon. Also might even be liquidating my hynautic steering depending on how I rig the new Bravo.

SS18
03-17-2002, 05:00 PM
Kent,
Here is a tip.Get the tyvek suit from paint store,spray hood,gloves and goggles.Use a little baby powder on your face ,wrist and fore arms.The powder closes the pours of your skin and don't forget the cold shower! eek! I've been grinding on the minx at least five hours in the hull for stringer repair.That's complete I sistered existing stringer and used some woven roven,then
chop mat.Gel coated saturday and ready for the new tank to be installed.Now for the top half floor repairs.Another couple hours of grinding and
replacing the floor cores and got rained out! Oh
well always tommorow.What are you working on? Not
the 18.
JIm in NJ

Kent Perroux
03-17-2002, 10:21 PM
Actually I am working on the 18 Jim. I decided to keep it. I pulled the engine, rebuilt and painted it with blue metallic imron. Looked so good I decided to strip the engine compartment for white allgrip paint. While I had all that out, why not raise the outdrive? When I pulled the outdrive, I was going to plug the hole and recut it. Well, might as well do it right so I ripped out the transom. What the heck, time for a Bravo drive. Volvo drive should be gone this week. Today I just bought a set of Gaffrigs, so this week the gauge panel is coming out.

So lets see what will be different:
1) Bravo 1 Drive
2) 2" higher X-dim (Imco shortie later)
3) New engine
4) Less weight (I think I dumped about 150#
5) Semi-dry exhaust
6) All new wiring
7) All new Gaffrig Gauges
8) External Steering

I think I will have a new boat.

clayman
03-18-2002, 07:42 AM
I am working on the restoration of my 18 , lets see some pictures???? what you have done sounds pretty interesting.
Jim

Kent Perroux
03-18-2002, 11:43 AM
You can see the motor on another thread. The engine compartment is a real mess right now. Washed out all the fiberglass dust yesterday so I could see, cut all the wiring and contemplating moving steering to the right side.

I'll post some pictures as I get going.

Greg
03-18-2002, 01:19 PM
Clayman, I am doing the same thing to my 18. I'm fortunate to have an experienced fiberglass man overseeing my work. I've got the plywood cut and laminated so hopefully later this week he and I will be installing my transom. As soon as we do that I will figure out the picture poating here and put up some pics. As for right now I am in the same place Kent is, there just isn't that much to look at.

Kent Perroux
03-18-2002, 01:58 PM
Is everyone using Marine plywood? No new composit materials?

SS18
03-18-2002, 06:56 PM
Kent,
I used 5 ply AC plywood we are using this on decks of homes and fiberglassing.Sealed both sides
with winter resin for us northern guys.I have a good friend who does apply about 2000 gallons a
month in our conditions the resin was developed
for superior flex and strength.The 5 ply AC is as good as marine because if your marine is getting wet it will eventually delam as well so.Marine was a big deal but these days even just plain CDX
sheathing is getting high tech resin glues although mostly three ply not good for our use.I
mix nice hot resin seal both sides and go to work!
AC is rated with no interior voids that was the main concern with marine in the past.Use good resin glue when laminating and you will be fine with good AC.
Jim in NJ :cool:
PS I have picture of the nearly completed minx
but not sure how to post.Any help appreciated. :confused:

harbormaster
03-18-2002, 10:10 PM
Go to the following link and read it. It should help you post your photos.

http://www.donzi.net/instruct/index.htm

CDMA
03-18-2002, 10:28 PM
http://www.donzi.net/photos/callard89.jpg

http://www.donzi.net/photos/callard90.jpg

This is my version of a transom. Follows basically the ideas of Geoo's transom rebuild in the tech section. I can't remember which boat this is off of but both are similar. 2 layers mat, 7-8 layers bi-axil, 1.5 inches of marine ply, 5 more layers of bi-axil. Then entirely vacuum bagged. This was the key to my lamination. Makes the layers of glass so tight they are hardly discerable. Maybe overkill but with 600+ hp overkill makes me feel warm and fuzzy.... wink wink

harbormaster
03-19-2002, 08:05 AM
Chris,

You want to give everyone a brief description of how you do your vacumn bagging?

Kent Perroux
03-19-2002, 08:37 AM
CDMA,

Did you match the exact dimensions as the original donzi transom or did you go wider?

I am planning on going a little wider than the stringers, doubling up in the main stringers and having the transom overlap the stringers to increase load distribution to the main stringers.
Since I was going to go a wider, I am looking tino some of the new composites used by some of the race boat manufacturers to minimize the amount of weight being added.

The vacuum bagging is a good thought. I'll definately have to rig something up for that.

Kent

Looped
03-19-2002, 08:42 AM
Kent,
Make sure that you don’t go too thick on the transom because depending on which drive you are hanging on there they do have their limits to how thick you can go for the transom assembly. You probably know this but I figured I would throw this out here anyway incase some else decides to make an overkill transom and come to find out that they made it too beefy.

Craig

CDMA
03-19-2002, 11:33 AM
Craig is right about the thickness. I am not sure but I think a merc can only be 2.5 inches thick. Mine wound up to bu just under that and I had no issues with the alpha and now the Bravo.

The Vacuum bagging is a pretty in depth thing but not all that complicated. On the 18 I was working at Derecktor yachts in Mamaroneck NY and they had an entire set up they let me use. At school we have a vacuum pump set up that we use for hull models that I used on the 22. Basically after you do your standard layup you put a nylon ( I think) release fabric over the layup. Then you put a sort of gauze like sheet ( to absord resin) and then a plastic sheet. The plastic sheet is basically taped down along the edges of what you are vacuum bagging. Then there is a hose fitting on the plastic and the vacuum is attached there. I think we used 7psi but don't quote me on that. Then you walk away and just let it cure. This set up does a few things. First it makes a basically voidless structure, reduces excess resin ( therefore weight), it makes the layers of glass tighter therefore stronger and finally when laminating vertically it keeps the resin from running down to the bottom of the lamination.

Now if you don't have a set up to create a vacuum I believe there are ways to adapt a shop vac or an air compressor to actually create the vacuum. I have not looked into these methods however. My biggest recommendation to anyone interested in doing this is get all the West System Epoxy manuals and books. They really are excellent. Also West System epoxy has entire kits for this stuff.

Kent,

My 18 is standard between stringer set up. For this set up I believe this is more then adequate. My 22 is a full transom between the stringers and 1 layer of 3/4 ply ( in additon to the glass) all the way across the entire transom. I think it is just as important to properly tie the stringers into the transom. That is really where the strength for the upper part of the transom comes from. I am having aluminum gussets made to tie my aluminum stringers to my transom. It will basically connect the stringers, transom and extension box as one complete unit.

Oh one more thing. On my 22 the hull is glassed to the deck. The hull to deck joint is one aspect of the classics I find woefully poorly done. Self tapping screws just don't cut it. If I ever need to get the deck off I will have to cut the tabbing on the inside with a die grinder but I think it is worth it.

Chris

CDMA
03-19-2002, 11:40 AM
http://www.donzi.net/photos/callard91.jpg

Here is my 18 with the deck off. Note the stringers are also double wide in the rear and the "shelves" are actually structural parts of the lamination.

Chris

oldLenny
03-19-2002, 12:32 PM
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1525031462#DESC

Greg
03-19-2002, 05:07 PM
Kent, On my 18 I am installing an Alpha SS. The manual from merc says to go with a 2" min. and a 2 1/4" Max. They stressed that it has to be parallel front to back. I built kind of a frame around the outside of the hull and transom to keep them from bellying out when the deck comes off. Once I got all the bad wood out my transom was flopping around pretty good. I actually put my deck back on, built that frame and then removed it again. Deck install and removal wasn't bad with 6 people, average age 50. Would have been easier if two hadn't been dragged from the bar to help. I also have some drawings from Merc. showing how to measure and find the center. If you need any of these let me know and I will scan them in and send them out. Good Luck Greg

Looped
03-19-2002, 07:45 PM
Supporting the transom from trying to reshape itself may not be the biggest problem that you will run into if you take your deck off for a while.
The main thing that you need to do is take something like 2x4's and place them across the beam of the boat every 3 feet or so and secure them to the top part of the hull so that the hull will not bow in or out depending on how you have the hull supported (I have heard that some say the beam pulled in and some that have bowed out). This has been a BIG problem for some that have had their decks off for a while and come to find out that the hull and deck do not line up right once you put them back together. It may be a pain to work on the inside of the hull with the supports but it will keep you form a larger problem in the end.

Just another 2 cents thrown in,
Craig :D

jwright
03-19-2002, 09:42 PM
I have done vacumm bagging in my job, it is a nice way to compact a laminate. A great source for info is a small Gougeon Bros. book. I believe West Marine may have it in the WEST System display.
A good way to go is to use a venturi pump on an air compressor. Bagging materials can be found in Professional Boat Builder magazine, or from Gougeon Bros. (in small quantities).

Sagbay32
03-19-2002, 09:49 PM
Go to www.gougeon.com (http://www.gougeon.com) and sign up for their Epoxyworks magazine (free). They have all kinds of information available, and contact numbers of people who have built just about everything. If you are ever in Bay City, stop by and see them. Great people!