Center stringer? Do I need it?

[GaJeff]

Re: Center stringer? Do I need it?

Thanks, they didn't look stainless. And they shriveled up to nothing in the middle. When I had my outdrive off last year to replace the bellows I set the bell housing on the table to clean it up and kinda knocked it off and to the ground. Well I bent one of the studs. I have plenty of zinc bolts in the bolt bin and replaced the stud with a bolt. After about 3 runs the head started to rust. I go mainly in salt water so it didn't take long. Also from a little research, I found that I'm missing a few continuity wires and the springs for the trim ram bushings. Ill need to get these as well to keep the corrosion down.

Jeff

 

[Woodonglass]

Re: Center stringer? Do I need it?

WHOA!!! If you're in SaltWater most of the time I'd defintely go with the SS. You just stated why NOT to use the others. They won't last very long in the salt!!!!

 

[GaJeff]

Re: Center stringer? Do I need it?

I wanted to make sure what kind of bolts were oem. If they were zinc then I need to go another route. If stainless then I would buy them. I've lived here on the coast my whole life and salt water is the most corrosive thing around... It may take a while but it's bad.

So ill source up some SS hardware from somewhere other than Merc. There has to be an aftermarket supplier that makes them in stainless.

Jeff

 

[zool]

Re: Center stringer? Do I need it?

Hello GA, if im not mistaken, the lower studs for the transom shield have aluminum anode nuts, but the anodes are mainly to protect the shield, not the studs.

Aluminum Anode for Mercruiser Transom Shield Lower Mounting Bolts 55989Q9 | eBay

According to a post I read from the late Don S, may he rest in peace, you need to insure they stay dry, by correcting whats letting moisture to them, be it a wet transom, or leaking shield.

Heres another link for VP, but same principle, using galvanized steel bolts.

Transom shield mounting bolt failures

Hope this gives you some direction..

 

[GaJeff]

Re: Center stringer? Do I need it?

Thanks for the links zool, I was thinking g on using some kind of sealant on the shanks upon install.

I'm going to go to Fastenal to see if they might have some SS bolts I can use, if not ill go with the galvanized. My lower studs and center bolts were completely trashed. They came out in two pieces. The only part of all the bolts that looked good were the threads under the anode caps lol so I guess they were doing their job. My gimbal housing and outdrive are I. Great shape, no corrosion at all so I'm lucky for that.

Jeff

 

[GaJeff]

Re: Center stringer? Do I need it?

I bought a gallon of fumed silica from river supply and went through that already. I went to the guy Ive been getting all my resin and glass from and he had a 10lb bag of aerosil so I got a 5gal bucket from him and he told me that this would be way more than I would ever use.

Well tonight I ran out... I done the transom and a quarter of the way up one side of a stringer with the river supply stuff. I done all of the main stingers and one of the outer stringers and I ran out.

Am I using to much? I set my stringers in with pl and came back and done all my fillets.

Also the gallon I got from river supply, the fumed silica dried almost clear and used pretty much 1:1 ratio. The aerosil dries white and seems like its using 2:1. I measured out the gallon because I was doing pints at a time. Since the aerosil is in a bucket I'm scooping it out. Is there I difference between the fumed silica and the aerosil?

 

[ondarvr]

Re: Center stringer? Do I need it?

Aerosil is one brand name of fumed silica, but there are several types and grades of fumed silica, so the two products may not be exactly the same.

Silica can also absorb moisture, so if it's not stored correctly it can turn the resin more of a whitish color than it normally might.

 

[GaJeff]

Re: Center stringer? Do I need it?

Aerosil is one brand name of fumed silica, but there are several types and grades of fumed silica, so the too products may not be exactly the same.

Silica can also absorb moisture, so if it's not stored correctly it can turn the resin more of a whitish color than it normally might.

He had a 10lb bag sitting in the corner of the shop. I put it in a 5gal bucket with a sealed lid that twists off on the center. It was supposed to keep it dry, especially with all the rain were having lately. Maybe it was contaminated before it got to me?

Jeff

 

[GaJeff]

Re: Center stringer? Do I need it?



Need some advice on this. These side panels are hollow boxes made from 1x4 boards. They dont seem to be structural at all. I had panels screwed to them just for looks. I was wondering if it would be ok to remove them and run my deck all the way to the edge. As it sits now, the deck will be just above the bottom board. Also when sitting at the wheel its like im almost sitting above them and my feet really dont have any room to sit comfortably.

Jeff

 

[Woodonglass]

Re: Center stringer? Do I need it?

IMHO those are structural and need to be there.

 

[zool]

Re: Center stringer? Do I need it?

I agree with wood, if it was put there, it needs to be. Builders didnt generally add any addition structural components other than whats needed or mandated by regulations, at least with price point boats.

 

[GaJeff]

Re: Center stringer? Do I need it?

OK sounds good to me. They are solid and dry. Actually the only wood pieces on the entire boat that is good, so ill grind them down to clean glass and reseal them. Thanks

Jeff

 

[ondarvr]

Re: Center stringer? Do I need it?

Those do add support, but few boats of that era had any engineering done on the laminate schedule or anything else, they just built it as strong as what they thought was needed and if it broke they made it thicker. So while I’ve seen boats use that method, more of them with very similar designs don’t, so is it needed…hard to say. Many boats were designed on a napkin at a bar by a couple of drunk guys that may or may not have had any idea of what they were doing, or how to work with fiberglass. So many designs didn’t really work out all that well, they still built and sold them though.

If you wanted to remove them you could just add some glass to that region, that along with the floor extending out to the side of the hull would most likely add enough strength to replace what may have been lost by taking them out.

 

[GaJeff]

Re: Center stringer? Do I need it?

That is a valid point too....HMM what to do what to do?

 

[Yacht Dr.]

Re: Center stringer? Do I need it?

You could use the old method of cardboard tubes cut in half and then lam then for your cross supports .

Its only a 20 footer.

YD.

 

[GaJeff]

Re: Center stringer? Do I need it?

You could use the old method of cardboard tubes cut in half and then lam then for your cross supports .

Its only a 20 footer.

YD.

What do you mean for cross supports? Take them out and use the cardboard tubes along the side like the original panels or what?

Jeff

 

[Yacht Dr.]

Re: Center stringer? Do I need it?

What do you mean for cross supports? Take them out and use the cardboard tubes along the side like the original panels or what?

Jeff

The rip cut of tubes ( they have to be large enough for the system being applied ) will be used as a Form for the glass overlay.

The Glass at this point will be your stinger and/or sub bulkies.

Its only used as a Format for your glass lams. The fiberglass will dictate how strong the location is at THAT POINT ONLY. You dont need wood in certain locations .. you only need a proper build of fiberglass to distribute the load of the hull.

The Tubes only create a easy layup of the glass ( the Tubes do not matter after the fact of the fiberglass lams ).

Its only used for the Template or Pre-lam forms.

You can build a boat without Any wood as long as you have a structure with composites. ( Glass )

YD.

 

[GaJeff]

Re: Center stringer? Do I need it?

I got my stringers all tabbed in with the exception of the port side outer stringer. When I ran out of the cabosil I started laying glass and haven't mounted the stringer yet. I went out and got another 5gal of cabosil so ill be installing that stringer tonight. I still have to cut it and shape it before I can put it in. Ill probably glass it in tomorrow. The hull seems to get a little warm when using the PB to bed them in.

I've decided not to mess with those side boxes. They are completely dry and I really don't want to start the grinding all over again. Plus they were used as bottoms to the side storage and I kinda don't want to get rid of that.

Jeff

 

[GaJeff]

Re: Center stringer? Do I need it?

Well finally ALL my stringers are in and glassed up. Ill be making my fuel tank and ski locker boxes next and then ill be ready to put the deck in. I still have to get some bolts for the gimbal housing so I can mount that and make my engine mounts.

Also the guy I get my resin from gave me something a little different this time. Usually I have been getting the iso resin and its a pink color. Since they are building this pump house structure and it calls for "marine grade" resin, I'm getting what they have in stock. It's an ortho/iso blend and a really dark green color. He told me it would have about a 30min gel time at 1.5%. I really like the other stuff but this blend is awesome. I know that I will probably need more resin before I'm done so I hope he's not out before I am. It does last about 30min. at 1.5% although it doesn't seem as flexible as the iso. Either one to me is better product than the resin you get off the shelf.

Ill post my pics tomorrow

Jeff

 

[GaJeff]

Re: Center stringer? Do I need it?

Since I cut the back portion of the cap off to do the transom what's the best way to glass it back together? I cut it like a puzzle so it wouldn't be a straight line and hopefully carry some of the load when I put it back together.

My side panels on the cap are wood cored. I was thinking on removing some of the wood from the installed cap and the back part I cut, lam a piece of 1/2" on the backs and glass it up. Then kinda groove out the cut line and fill it up with PB and glass over that.

Suggestion?

Jeff