’97 Starcraft Corroded Transom Repair using Pourable Ceramic

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Johnny
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

eeeewwwwwwwww


Dale, I was just thinking of you today . . . wondering what you have accomplished so far.
looks AWESOME !! LOL from the "metalsmith's" point of view LOL nice challenge, to say the least.

Do you remember saying . . . But in my case, I bought the rig at the right price :D , full well knowing that I’d have some expen$e and have to do some work on her - but I was ready for it! No surprises.

are you still within your budget ? I know the "time factor" flew right out the window on this one.
I am very familiar with the Cleco fasteners .... once you do some metal work, nothing else will do.
I like those little clamps too.

good luck !!!!
https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

The next challenge ...

Replicating the shape and rounded corners of the old transom piece without buckling it or tearing it from the sheet panel of 5052-H34 I bought. Looks like I'll be annealing the corners carefully. At least 5052 takes a bend easily.

That heavy scored line you can see right before the rolled corner is where the transom rear skin met the topsides or hull bottom.

--------------------------------------------------------------------------------------------------------------------------------------------

5052 Aluminum Alloy
This is the highest strength alloy of the more common non heat-treatable grades. Fatigue strength is higher than most aluminum alloys. In addition this grade has particularly good resistance to marine atmosphere and salt water corrosion. It has excellent workability. It may be drawn or formed into intricate shapes and its slightly greater strength in the annealed condition minimizes tearing that occurs in 1100 and 3003.

Applications: Used in a wide variety of applications from aircraft components to home appliances, marine and transportation industry parts, heavy duty cooking utensils and equipment for bulk processing of food.
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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Update:

First shown is the piece I need to copy exactly. Then see the PDF article on 'hammer forming' aluminum. That's what I need to do to form the two corners in my transom piece, plus the center V area (16-degree deadrise).

I will anneal the aluminum first and bought a 650-degree TempleStik so I can't mess up (the annealing temp of 5052 alloy). I'll try my hand at annealing the bend area using MAPP gas. Then I will use a big flat, heavy rubber mallet to form the stern piece. I am using the old stern piece of 1-1/2" plywood as the form, where I cut the 3/8" radius on the edge with a router. I'll place a piece of hardwood across the top immediately behind the edge to be hammer-formed, so that the edge area absorbs the hammer blows.

That PDF article on hammer-forming makes it look pretty easy. And they formed that cap using 1/8" (0.125") thick :shock: aluminum. At least I'm only using 0.090" thick piece of 5052-H32 aluminum, lol.

FWIW I took it to a not-so-local hot rod guru who is the alleged zen master with forming sheet metal ... and he wasn't interested in the job :( . But at least he told me to research aluminum hammer-forming on-line and advised how to do it myself. And 'at best', he said, that even if I created a small crack or such 'at worst' ... just get that area welded.

Wish me luck ... I will need it!
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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Hammer Forming a NEW Transom Piece:

If you don't know what 'hammer forming' is, it is a method of forming metal alloys by annealing the piece of metal and then using a form and a large, heavy flat-faced hammer or mallet of wood, nylon or rubber (but NOT metal) to bend and coax the metal to form a new shape. In my previous post just above this one, I have a PDF showing someone making a round dome out of 1/8" thick aluminum. They made it look easy! With a properly annealed piece of metal, the metal will stretch or shrink, depending on whether or not you are doing an inside or outside formed corner.

You can see my layout lines, as I just drew a central line (square the the transom), then others lines parallel to it and 2" out on each side, then measured just to the 'top' of the radius of the bend.

Annealing:
I used 5052-H32 alloy, the same as Starcraft used, and it anneals at 650-degrees F while it's melting point is > 1100. I bought one of those special TempilStiks brand sticks that melts at the temperature you want. I use to use low-temp ones to troubleshoot OB thermostats, so I was very familiar with their use.

For heat I bought a MAPP gas gun and nozzle, as most cheap propane nozzles shouldn't be used with MAPP gas. This nozzle gave a great flame tip and the alloy heated up quickly - just DO NOT keep flame in one spot. I found it best to start from an end and work a 3-4" area. Once the tempstik melted on that area I moved on. On the corners, one must heat the ENTIRE surface or it won't fully shrink or stretch, but will ripple on you.

This was my 1st time doing this and I found the aluminum to be pretty forgiving. Aluminum will naturally harden in air and it also work hardens, so when forming that 1st corner, once it started to be more difficult than it should have been ... I stopped and annealed it again.

I think the pictures tell the story pretty well! I didn't form the 'V' at the center of the hull and up to the other side yet, but I was able to test fit the starboard corner into the existing stern-less hull and I'm pretty pleased!
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Johnny
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

wow - next month you will have an old forge and stake bed table in your back yard

look up " Planishing Hammer " when you get a chance. . . . . that might be your next calling.


But, from a true Craftsman's point of view, you can not replace the hammer and anvil approach.

Thanks for sharing !
https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Well I finished up the 'V' and formed the port corner ... and she fit into place, albeit off in a few spots, namely the corners of course. I might just find a tin shop where they may let me use their planishing hammer in exchange for some adult beverages for the crew ...

But at least this worked :D ... now to fit it, then rivet her back together ... and THEN pour the ceramic core transom material.

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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

after looking at the Harbor Freight planishing hammer, all it is is the Air Chisel in a frame.
So, I was thinking about modifying some of the chisels with different style heads.
I guess a heavy duty block of lead or iron anvil would work as the backer.
LOL I think everyone has at least one of these things in their garage somewhere. (I have 4).
So I have several bits that I will never use. I have a piece of 1/2" x 2" x 24"
steel bar that I can cut off pieces with the angle grinder cut off wheel and then weld
the heads onto the chisel bit. Then, shape on the grinder to different styles.
Less than $20 and you have a very nice Planishing Hammer with custom heads!!!
air chisel.JPG
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https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

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Johnny
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

Dale, about how many square inches are you working with on the corners ?
I guess I am interested in how long the annealing lasts under the hammer
before it needs to be reheated.
I have worked with sheet steel in car bodies quite a bit, but, never aluminum
to the extent you are doing now.
I guess common sense tells you when it is about to crack or split by the sound or feel ???

muy bueno hombre
https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

NEW Transom Piece Fit:

New piece 95-99% fitted, just need to do a little more 'tin knocking' to make sure she fits all corners and profiles.

Starcraft told me to clean & prep the surfaces well, then put 3M vinyl foam tape on the hull, wetted with Plio-Bond waterproof rubber cement. I already use this for dressing saltwater flyfishing shooting head connections and it works great. Now I just need to get a BIG bottle of it.

Plus I will also dip the rivet w/ 3M 5200 before bucking. I will also prep the mating surfaces w/ epoxy-based acid etching zinc chromate ... as I want this to be the LAST transom this boat ever needs.

For Johnny:

BUDGET? Oh heck, I blew that a LONG time ago ... I'm only in 'knee deep', but I dove in, LOL!

AREA: I first annealed the good 1/2" + on either side of my line, but that wasn't enough. Where metal needs to shrink (my case for outside corners) or expand, the ENTIRE surface being worked needs to be annealed. I had to do a few spots a few times.
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Johnny
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

wow - looking good Compadre !!
Pogo's Boat.jpg
Thanks for sharing !! very educational indeed








.
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https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

rdhammah
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by rdhammah »

All I can say is my Captain does good work! Dale - that looks awesome!

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Latest Update ...

Well, life got in the way, and that included taking in two girls (ages 11 & 16) to live with us after a death in the family, so I had tons of other priorities besides working on the boat. But my crew (RDHammah) came by and together we got the transom fitted in and riveted in place!

I think the pictures help tell the story, but if you had any questions - ask away. I put 10-24 bolts and nuts, using large fender washers, in at various spots just to hole the positioning of everything. Then I drilled for the rest of the holes. And I will say - EVERYTHING lined up! Sweet!

For those who need details, the sealing tape is a 3M closed-cell vinyl foam that Starcraft recommended. All surfaces were prepped and zinc-chromated beforehand. Then the tape lain down, black 5200 applied and then off to riveting we went. I used a $20 Haba Freight air hammer at 75 PSI, with the special brazier head tool and it worked flawlessly.

As they say in Boston ... WICKED PISSAH!
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Johnny
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by Johnny »

Them there is a whole passel of rivets !!
=D>
Great work - from tear down to tear it up to putting it all back like new.
awesome tutorial !! Can't wait to see the Transom Pour, when you get to it.
https://www.tinboats.net/how-to-build-a-transom/
https://www.tinboats.net/varnish-vs-polyurethane/
All about Primers = https://www.tinboats.net/primer-and-paint-basics/
Paint, Thinners and Applications = https://www.paintingforpainters.com/

1959 Crestliner Commodore 14'
1958 Johnson 35 RDE-19 Sea Horse
1958 Johnson 35 RDS-20 Super Sea Horse

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Barefoot_Johnny wrote:Them there is a whole passel of rivets !!
If I recall correctly, we'll set almost 300 rivets putting the new stem in place. We did good - so far we only replaced 2 or 3 poorly set ones, typically where the tail kareemed off to one side and didn't sit flush or square.

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DaleH
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’97 Starcraft Corroded Transom Repair using Pourable Ceramic

Post by DaleH »

Starboard stern completed:

Not too bad ... I wonder if Starcraft is hiring? I'm just thrilled that the new replacement transom piece that I hammer formed went into place and is now locked in place permanently! Now to complete the aluminum bracing inside the transom and get ready for the pouring of the new ceramic transom compound ... which is how this post originally started, LOL :shock: !

Details - - - - - -
Jay-Cee 3/16" rivets, 1100F alloy, brazier head
Haba Freight $20 air hammer
Borrowed compressor, set at 75psi

Time for a cold one!
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