Man of Steel Goes Aluminum

[g0nef1sshn]

4200 = more removable than 5200 = darn near permanent. Time dry is just that. My .02 cents and help.

 

[classiccat]

Thanks Waterman and Prepmech.

Another question on adhesive sealants. Besides cost, what is the difference in the 3M (or other brands I suppose) of 4200 vs 5200? Any thoughts (other than time) on the quick dry vs regular?

From what I have seen in some other discussions, it sounds like when I have the new transom made, glued and sealed, then I should:

1) put the transom back in,
2) mark the holes where I will be drilling through for things like the motor mounts, swim ladder, etc,
3) pull the transom out,
4) drill out the holes, oversized
5) make and fill with the special peanut butter made from sawdust and one of the adhesive sealants
6) put the transom back in (after any work is done on the area surrounding the wood transom) and secure
7) redrill the holes with the correct diameter for attaching the motor mounts, swim rail etc.

For any holes in the aluminum back of the boat (don't know if this is also called the transom?) which I am not going to use:
1) fill lightly with JB Weld
2) sand flush.

This certainly feels like a "Star Trek" as I boldly go where this man has never gone before. I am very thankful the Star Fleet Academy is around to advise.

Nice job on that motor stand!

The oversized holes are for epoxy + filler (like colloidal silicon, cabosil, etc.); example on my SS project. That's pretty bullet-proof. Another way is to drill the holes to size & saturate the freshly exposed PLY with your favorite sealer ("Old Timer's formula, Spar, Epoxy, etc.).

A trick with patching holes with JBWeld is to butter-up a piece of aluminum flashing, Put a piece of painter's tape on the exterior side of the hole to keep the JBWeld in place while it cures, then tape the buttered-flashing to the inside of the hole. I like to sand / clean the flashing & inner hull skin before applying...make sure the JB gets a good grab.

 

[Watermann]

Looks like a complete list. There's just one other thing sometimes guys forget about is the beveled cut (15 degrees) on the sides of the transom on either side of the cutout for the outboard. Commonly referred to as the transom wings. If those aren't cut to a bevel then the gunnels, transom covers and end corner caps won't go back on.

I use only regular 5200 on the bolts and I don't mess with over drilling the bolt holes to insert some concoction. I just makes sure there's plenty of 5200 on the inside of the holes and the bolt shaft when they're mated. Then there's no worry about water getting inside to do damage.

 

[PikeHunter431]

Thanks g0nef1sshn , classiccat and Watermann .

 

[PikeHunter431]

No Title

Spent most of my boat time today tracing, documenting and disconnecting the wiring for the motor. Eventually I was able to get the engine off and onto the motor stand. I still have to drill and bolt it to the stand before I take my deer hoist off it. But alas, the back end is almost clear now except for the speedometer sensor and some transducer cables. I also took out the 2 doors and bottom rail covering the bottom of the splash pan area.

 

[PikeHunter431]

No Title

Was able to get the transom out today. I was a bit perplexed on what to do about the horizontal aluminum strip that sits on top of the gunwhales and overhangs the top of the transom. As I am not planning on removing that strip at this time, I ultimately decided to just bend it up, thus out of the exit path of the transom. Then I discovered the PO had put the transom in as 3 pieces. The two top pieces were just loose and sitting on main portion of the transom. I guess that was the POs way of dealing with the strip on top of the gunwhales and not having to remove or bend it.

The wood was actually pretty solid yet. The PO had angled off the bottom corners of the transom on both sides. It did make it easier to get a 1x1 in under it to leverage it loose/out. I am not really sure about having that open triangular space in there when I make the new one.

Today, i also picked up the plywood, Titebond III and JB Weld.

 

[PikeHunter431]

No Title

I also took a couple pictures of the knee brace. One side has a pretty good crack running down it. On the other side, a chunk of it had cracked off. I have that piece as well. Looks like I need to get on with picking up some aluminum angle for each side.

 

[Watermann]

Awesome, you have a transom template and not a heap of mulch as some guys do. So yeah Starcraft builds transoms in 3 pieces like that, my SS and all the others I've seen come out in 3 pieces as well.

You now have to really clean the inner transom skin of all the corrosion. See the white on the transom wood? That corresponding area on the skin has galvanic corrosion that leaves nasty pitting, sometimes to the extent of being pinholes.

 

[classiccat]

Good progress Pike! I think the P.O. you're referring to was StarCraft :lol: That transom may feel solid to us however your knee-brace knows that it gave up it's ghost a long time ago.

+1 on what Agua said about the inner transom skin; it would be alot easier to clean that guy up with the splashwell out. Many of us remove the Z-brace (bottom transom bracket) as well.

 

[dozerII]

Wasn't mentioned but to make a stronger transom when you make your replacement make it one piece instead of three. Great progress.

 

[PikeHunter431]

You now have to really clean the inner transom skin of all the corrosion. See the white on the transom wood? That corresponding area on the skin has galvanic corrosion that leaves nasty pitting, sometimes to the extent of being pinholes.

For cleaning up the corrosion, is it best to use a mechanical process like wire brush/.wheel, a chemical process or some combination of both?

 

[PikeHunter431]

Good progress Pike! I think the P.O. you're referring to was StarCraft :lol: That transom may feel solid to us however your knee-brace knows that it gave up it's ghost a long time ago.

+1 on what Agua said about the inner transom skin; it would be alot easier to clean that guy up with the splashwell out. Many of us remove the Z-brace (bottom transom bracket) as well.

Yeah, I figured the transom wasn't in any condition such as one might put it back in. I was a little surprised I didn't see some visible/noticeable rot or decay given how old it must be if it is original Starcraft.

I am going to take out the splashwell next and probably not going to put it back in as is. My current hope is I can put a temporary raised deck in it's place until I can do a full gut later this summer.

Is the Z-brace the same thing as the Knee brace? If not, I don't think I know what you are referring to.

I was also thinking I would pull up the rearmost piece of the flooring in order to get a look at the bottom where it meets the sides and if I have any structural damage there (fingers crossed on this one.)

 

[Tnstratofam]

The zee brace is the bracket the bottom of the transom rests in. It runs the full width from port to starboard. The knee brace is the large brace that runs from the bottom hull to the transom. It is located in line with the motor on the inside. The zee brace is between the kneebrace and the transom so to speak. They do tie together for added strenght.

I removed both and sanded and primered both as well as the inner transom skin. I was able to just use a green scoth brite pad to sand the transom skin, then primered with zinc chromate primer then paint. I used a wire wheel on a drill for the knee and zee braces also.

 

[PikeHunter431]

Wasn't mentioned but to make a stronger transom when you make your replacement make it one piece instead of three. Great progress.

Thanks dozerII, I was planning on doing a one piece. I am not sure what to make of Starcraft's decision to put it in as 3 pieces. I would think the 3 piece approach may be easier (hence lower cost). It seems like it would be weaker. Perhaps it allows a little flex on the top back sides of the boat. It was loose and just sitting on top of the bottom piece without any sign of an adhesive or connector. However, I am with you in planning on a one piece transom.

 

[Tnstratofam]

I got lucky on my inner transom skin as there was only light pitting. Some people have deep pitting which requires some jb weld or marine tech to fill. I also replaced my transom without removing the splashwell. If I had it to do over again I would remove it for better access during the transom replacement.

I have seen some modified splashwells that were shortened to allow for more casting area at the stern, but there is usually extra bracing added to the gunwales when this is done. I've also seen castng decks installed above the splashwell, but it seems a little high and unstable for my tastes.

 

[PikeHunter431]

The zee brace is the bracket the bottom of the transom rests in. It runs the full width from port to starboard. The knee brace is the large brace that runs from the bottom hull to the transom. It is located in line with the motor on the inside. The zee brace is between the kneebrace and the transom so to speak. They do tie together for added strenght.

I removed both and sanded and primered both as well as the inner transom skin. I was able to just use a green scoth brite pad to sand the transom skin, then primered with zinc chromate primer then paint. I used a wire wheel on a drill for the knee and zee braces also.

Thanks tnstratofam for the clarification. I can see where removing that piece would ease the process. If I am understanding you, you primered these interior facing parts. Did you also paint these interior facing parts? (I have seen/read about people doing this on the exterior and some open facing interior parts).

 

[Tnstratofam]

On the interior pieces I primered first with zinc chromate primer ( Rustoleum Aluminum Primer from Lowes ), then just regular gray primer. I did repaint my splashwell and stern. For that I used the zinc primer then a Rustoleum beige that closely matched my hull color.

We bought our SS needing a transom, but with a new deck. So it wasn't a full resto. There is a link in my sig to my transom replacement. You may find some info in it that will help.

 

[jimbotek]

Hi Pike Hunter:
I think Starcraft put the wings at the top of the transom because they ripped a 4x8 sheet down the middle for the bottom part rather than trim two whole sheets. I think the height is 29?. I took their approach but got more height than the transom that was in there. I ripped the one sheet, bonded the two halves with liquid nails construction adhesive, then traced my cardboard template for the cut. I went a step further and fastened the wings to the main transom with an overlap joint. (see pic). I think it would help if you removed the splashwell. You stated you?re losing it anyway so why wait? Drill out all the rivets you can as you gut the boat so they?ll be cleaned up with all the other mucky muck in the hull bottom if you haven?t already.
You seemed interested in vinyl flooring. I?m going with vinyl rather than carpeting due to the climate. I would advise you not treat your plywood decking with varnish, etc. if you intend to use adhesive for the vinyl. I doubt the chemistry would be compatible. I?ve been following your post but I will begin my own soon. I live 30 miles west of Plattsburgh by Union Falls. I am restoring my 18 footer to original configuration. I am hoping to complete it by June. Good Luck!

 

[jbcurt00]

Varnish is compatible w adhesives for vinyl

Several members used Spar Varnish on the deck plywood before gluing Nautolex down.

I would advise against using less then full width plywood for the transom. A few have had trouble w using liq nails or PL for lamination of the transom. But that can all be a discussion in a topic about your boat and rebuild Jimbotek

 

[PikeHunter431]

No Title

We had an unexpectedly nice day and I had it off, so some good progress was made. I removed the splash pan, partly for the ease of working on the stern area (thanks for that suggestion everyone) The other issue is I wanted to get down and inspect the interior rear section of the hull to check for any remaining significant structural issues which I should address before using the boat in late May. So out came the splash pan.