1969 Larson - Big Project

[avpaulb]

Re: 1969 Larson - Big Project

@ ZenFerret... I am intrigued by your response. My glass is in fact plexiglass. If there were a way to fix it, I'd love to know. I would mention that it does have a couple of significant cracks...

@ Yacht... upon further investigation, "center open tub" is correct. I had to work late tonight so I didn't have time to work or post anything new this eve. My hope is to have a somewhat early night Friday, or have all weekend to wreak boat havoc. I'll post more. The "tub" is somewhat thick, maybe 1/4" in some spots. However, from bow to stern in the bilge, it is highly un-level, and probably can be redone. And, strangely, underneath the "tub" is a thin layer of foam. Weird.

After I took the spade to the old foam I am down to basically hull at this point. The only thing "fiberglass" remaining is the bottom of the old bilge bay, and a very spotty layer of CSM along the interior sides of the boat.

During the week is tough for pics for me. In good old MT we deal with REALLY spotty weather patterns this time of year. At worst, I'll get some pics going on Saturday of the entire breakdown, and we'll all go from there!

Thanks again everyone! I know what it is like being experienced in something and monitoring "noobs"! Maybe someday we can reverse roles and you can visit one of MY expert forums! But, succeed or fail, I'm loving ripping the heck out of this thing!

From previous replies: my current transom-top to "V" height is 20". If I level the transom, without the wetwell dip, it will be 23". SO... @ Woodonglass, if my math is correct, the shaft lenght on my motor is approximately 22-23 inches currently. I am measuring from my mount to the motor's "fin", as in your picture. SO, by increasing my transom height to 23" should be spot-on?! Yes? I have time to stew on this anyway. I still need to finish getting all of the muck out of the boat and tearing off the back of the cap before I even think about it.

More coming everyone!

 

[Willyclay]

Re: 1969 Larson - Big Project

From previous replies: my current transom-top to "V" height is 20". If I level the transom, without the wetwell dip, it will be 23". SO... @ Woodonglass, if my math is correct, the shaft lenght on my motor is approximately 22-23 inches currently. I am measuring from my mount to the motor's "fin", as in your picture. SO, by increasing my transom height to 23" should be spot-on?! Yes? I have time to stew on this anyway. I still need to finish getting all of the muck out of the boat and tearing off the back of the cap before I even think about it.

I overlooked your earlier mention of already having a 20inch high transom but this time you got my attention! Any discussion of "short-shaft and long-shaft" motors needs to stay focused on the actual dimension of the transom. You may need to leave it as is. Take a look at this link and see if it gives you any additional info. Good luck!

http://www.boatmotors.com/ref/shaft_length.html

 

[avpaulb]

Re: 1969 Larson - Big Project

I think I may have initially misunderstood that picture. It looks like we're finally having a sunny day here. With some luck I'll try to take some pictures later today with a good camera so we're all on the same page!

Good day all!

 

[ZenFerret]

Re: 1969 Larson - Big Project

@ ZenFerret... I am intrigued by your response. My glass is in fact plexiglass. If there were a way to fix it, I'd love to know. I would mention that it does have a couple of significant cracks...

Completely remove the old windshield and trace the outline on a large sheet of paper. Use that as a template to cut your new windshield from a sheet of plexiglas, and you can then bend the curves by heating the plexiglas with a heat gun (or other heat source). If you do a google search on "bending plexiglas", there are several ways to accomplish this. I've read that Ed "Big Daddy" Roth used a pizza oven to heat the plexiglas that he used for bubble tops on several of his cars.

 

[avpaulb]

Re: 1969 Larson - Big Project

Definitely going to try the glass thing. Down the road though. Our weather has been going from snowy to warm every hour, so I'm trying to get bits and pieces done on the breakdown today.

Was able to remove the wetwell portion of the cap to get at the transom. That was entertaining. Let's just say that the transom is just about as rotten as it gets. I'll be posting pics in the next day or so.

 

[avpaulb]

Re: 1969 Larson - Big Project

Decent progress on the breakdown today. Got the splashwell removed to reach the transom:



As well as a good portion of the remaining deck and "stringer" remnants:





I've discovered that the sides of the boat also have a thin layer of foam covered by old blown-in fiber. This foam is also waterlogged. The foam itself stretches from where the decking was, to nearly the top of the hull. I marked it with a line on the next picture.



So the question of the day is this: should I sand off the thin layer of glass and foam? Is that foam really needed? I'd be inclined to replace it with a couple of layers of CSM or something.

Also, in regards to the splashwell: is it a functional part of a boat, or can I just get rid of it? I have some ideas of what I can do in that location instead.

Anyway, finishing breaking down the remainder of the interior tomorrow, and beginning the transom work.

 

[Pmccraney]

Re: 1969 Larson - Big Project

Hmm... good question... I would definitely raise the transom if you are going to eliminate the splashwell...

Also, you may want to consider some type of draining mechanism (bilge box/pump to collect water and pump it out or maybe even some scuppers) just in case do take a little wash over the back (which will happen).

Just a little brainstorming... the pros will come along shortly with better, more-informed guidance..

 

[avpaulb]

Re: 1969 Larson - Big Project

Decided to keep the splashwell.

Much progress today. I was able to get a major portion of my grinding down done, as well as completely removing the old transom. Check out the picture! That pile you see is in fact the transom! So wet that it just ripped to pieces!



I took a picture closer-up of the strange layer of CSM covered foam lining the interior...



You can see that I had to sand some of it out to get to the transom. Still looking for any guidance as far as removing this foam layer and re-coating the hull with a couple layers of glass. The foam that is underneath is nice and wet/rotted.

Anyway, a couple of other pics before I close, just for fun...

Under the deck, still digging...



Transom removed!



The old transom was held in with wooden dowels, poorly sealed. Hence the source of the dramatic water problem!

 

[avpaulb]

Re: 1969 Larson - Big Project

I think I've been posting too late at night... by the time everyone is awake my thread is long gone! So, I'm bumping myself...

I did forget about an old fiberglass trick yesterday that I would like to remind everyone of: if you are going to be working with glass, give yourself a good rubdown with baby powder or talc powder. This will avoid the itchiness and burning you get when glass dust sneaks through your super-suit.

Advice for anyone getting ready or thinking about working on a boat like this: go ahead and remove the entire cap! I wish I did now. Things get pretty tight in these little things!

Anyway, I had some questions in the above posts that I wouldn't mind getting answered...

 

[Woodonglass]

Re: 1969 Larson - Big Project

Any foam that is wet, must come out. If it's structural, it must go back in. You shouldn't have any issues with space getting the transom back in. The Talcum powder is well documented here on the forum. If you have a closed bow then yes, removing the entire cap is prolly the best thing. Good decision on using the splashwell, it is structural.

 

[Yacht Dr.]

Re: 1969 Larson - Big Project

Are you saying that you have a Foam filled core Hull/sides that is wet ? .. not the bottom..but the Sides of the hull foam sandwitched hull ?

YD.

 

[avpaulb]

Re: 1969 Larson - Big Project

Are you saying that you have a Foam filled core Hull/sides that is wet ? .. not the bottom..but the Sides of the hull foam sandwitched hull ?

YD.

That is correct... the sides of the hull, above deck, are foam sandwitched. I found it strange as well. My inclination is to get rid of it. It is quite poorly sealed. You can tell it's been wet many times over the years. It feels like an old nerf football that's been soaked and dried.

I'll try to get a better picture when I get back to it. Odds are I'm going to remove the entire deck, remove all of the weird foam stuff, and re-glass the hull all of the way up. There is also the same foam throughout the cap of the boat. Not sure what the story with the stuff is. If I had to guess... it was the mold for the boat that the fiberglass was applied to during construction. Non-functional.

Literally everything from the deck and under was soaked. Very few dry spots. The transom literally crumbled. I'm currently left with basically a shell, which on a boat this old might be ok!

 

[avpaulb]

Re: 1969 Larson - Big Project

Any foam that is wet, must come out. If it's structural, it must go back in. You shouldn't have any issues with space getting the transom back in. The Talcum powder is well documented here on the forum. If you have a closed bow then yes, removing the entire cap is prolly the best thing. Good decision on using the splashwell, it is structural.

Funny thing about talc and fiberglass... I've worked with fiberglass for many years, just not on boats. In my excitement to get this project rolling I completely forgot. Result: itchy, burning arms yesterday. Dumb.

I figured I would educate other rebuild noobs like me since I already knew better!

 

[avpaulb]

Re: 1969 Larson - Big Project

I found these pics from user coolbri70 (?), who has virtually the same boat as I. I've attached a picture of his original factory "stringers", which were in much better condition that mine. There seriously was nothing left of mine but evidence of what was there. Now I'm wondering if I should try to recreate this layout rather than creating my own stringer system???





Interesting question...

 

[Ironpig]

Re: 1969 Larson - Big Project

I have the same boat, and I am also in the middle of a small rebuild lets say. I figure its easier to rebuild the stringers that are there rather than trying to re-engineer the whole bottom of the boat. I figure to use better materials than the manufacturer so it should last a lot longer. Keep up the good work, looks like you've got lot of time into her already. What part of MT are you in? I'm up in Calgary and we get down to Flathead quite a bit.

 

[zarillus]

Re: 1969 Larson - Big Project

I actually rebuilt my stringers using a grid system to make it absolutely solid and forego the rotten foam fun.I used foam and pvc to channel water out if it ever got underneath the deck.I used 2x10's for my main center stringers and followed that all the way to the Transom.The result is that the Transom completely overbuilt but strong as hell.PM for a diagram and more details if you like

My two cents...

 

[Yacht Dr.]

Re: 1969 Larson - Big Project

That is correct... the sides of the hull, above deck, are foam sandwitched. I found it strange as well. My inclination is to get rid of it. It is quite poorly sealed. You can tell it's been wet many times over the years. It feels like an old nerf football that's been soaked and dried.

Hmm.. bummer..

Your looking at a lot of work bud.

I would suggest that you recore sections one at a time and not the whole thing at once.

Normally I would Vacuum bag new core in.. but that system is kinda pricey for a one time job.

YD.

 

[avpaulb]

Re: 1969 Larson - Big Project

Farther south... I'm in Bozeman, just about 60 miles north of Yellowstone Park. I am quite fond of the Flathead area in general. I have quite a few friends in that area.

 

[avpaulb]

Re: 1969 Larson - Big Project

Hmm.. bummer..

Your looking at a lot of work bud.

I would suggest that you recore sections one at a time and not the whole thing at once.

Normally I would Vacuum bag new core in.. but that system is kinda pricey for a one time job.

YD.

you just caught me on a term I haven't heard yet... "vacuum bag"... ? Clarify please.

I know the project is likely quite a bit of work. My inclination is that because this version of the 69 All-American is so basic, if I give it some time and patience, and take advantage of the knowledge of forum members such as yourself, I can pull it off.

Regarding the "weird hull-side foam", I can actually quite easily re-create that if needed. Clarification of "vacuum bag" is interesting though.

Thanks again for your thoughts!

 

[avpaulb]

Re: 1969 Larson - Big Project

Some other knowledge I could use... if anyone has any suggestions about how I can squeeze the most time and funding out of my wife to complete this project... that would be useful!

I already know that with my current wood-working and fiberglass use experience I could make this thing "seaworthy" in short order, but spending the necessary time and effort always seems to result in instant chastising. Bummer for all of us I'm sure.

Miracle in MT... my locally owned hardware store actually had marine plywood in stock. I'm good to go there!