Very much agreed

transom
 

ground off the excess. And cleaning up the skin I should have done this when the skin was just pulled off and the wood was wet.. Would have been easier.. Boy I wish I had a belt sander..

Outer Skin
 

That outer skin looks beefy. How thick is it?

Do you mean an air chisel with a wide blade? ;)

I saw something new at lowes that would work well for this. It was a wide scraper blade on a chisel that would fit a standard sawzall. They were only like $10 and it looked like it would work well for something similar to what you had to do.

I use my dewault 7 inch buffer/grinder with a 16 grit pad on it with the variable speed all the way up. Actually works better when the wood has dried.

Yea 10/4... I will be getting a larger grit disc...using 36 right now... I ager workable better when wood us dry... When wet though the wire cup brush just ate awayat the wet wood....hope to have it done this weekend. Weather permitting...

about a 1/4 inch

Has anyone installed a reverse chin. so that to knock the spray down.. I like the look of spary rails. but dont want to install them.. I was thinking of putting a1/4 reverse chine on the chine startin at the bow and flaring it down about3/4 of the leghth of the hull. I know what you guys are probably thinking. But I heard these are wet boats... I have never ridden in a 23 But my buddies 24century has a reverse chine and it does not matter what angle or how hard it blows you don't get wet... So what is your thoughts and how does yours ride .in rough weather..

Well I decided to scrap the skin idea. Reason being is that I did not realize that the outer two skins i put on the boat were already at the stern. Meaning flush with stern. So I decided to just start wrapping the glass around the stern quarters.. I did a 1808 o-90 came out just under the hull gellcoat.i wrapped up about3 -4 inches... I finished this one Thurs day night. just to find Friday that my heat lamp got a little to close.. So now I had to repair the core cell. Friday night. I just ground down the corcell until i got to clean material. then i added 4 pieces of glass or until it was just over .. I wrapped up it with a piece of visquen to keep the material in place. My epoxy as it gets hot it gets more liquid or viscus.. O i had to place a piece of visquene on it to keep the glue and glass in place. Sat i ground the glass flat and this time ground the stern quarters farther down the hull side about10 inches and tapering up at a 45 degree angle. so that there is more there to keep the transom from ripping off.. I glued a 17-08 0-45 piece of glass to the transom ... once that started to get really tacky. I wet out a piece of 2oz mat. i mean really wet out...WHAT a PAIN IN the ARSE ..after the mat I mixed up some cabosil and resin and smeared on to my backer board and onto the mat...I had the bright idea to build a flat very flat panel so that i can mash it up against the wet glass and get a smooth and flat surface to fare to... I will let you know what it looks like... I may have just created a really big Mess..

transom pics
 

here it is .. I also had time to clean the bracket up I used a soda wash mixed with some sand to blast the noocks and crannies .. then I pressure washed for ever.. then let it air dry for a bout an hour, then I used a ppg Alum cleaner and shot with 545 Algrip primer

What did you coat that bracket with?

Bracket
 

I was told that the 545 algrip primer good on all substrates above and below water line...

Forgot to show the part before the burn out oven.. my friend owns a motor rewind shop in town. he let me use his oven to vaporized the rest of the powderecoat.. after it was pulled I blasted with baking soda and sand ...

bracket
 

here it is with a 250 hp motor stator.. the oven is 6' x 6' x h7 '

How hot is the oven? There is a sort of upper limit you want to respect with aluminum in terms of time at temperature. You are probably ok, but it is worth thinking about, as it can reduce the strength of the aluminum.

Yea 10/4... Well we hqve burned out many slum stators ..iron core.. and had good luck... These are pumps qnd motors with flow tollerancea for bearings and shaft alignments... I know that there are set points as to what materials are being burnt... I think he had it set at 800. For 3 hours.... Then u slowly bting temp down... I did not see any warping or cracks... I did spray some crack dye just to check the welds

bracket
 

We will see wen I put her through the paces 4-6 foot chopout saint Andrews passq

it runs suprisingly well... the old 115 pushs it fine for now... scrubbing and replacing the wood leaning post .. trim tabs... may look at transom replacement over the winter before trying to repower.. going to run it for a while and check the burn numbers .. if the old tower of power isnt to bad i may try to stay with it for the classic look.. the original plan was to close the transom... but im not so shure yet..

It's not a stress/warp thing, it's a strength thing. Some aluminum alloys lose a significant portion of their strength when heated near their melting point. You might want to look at the alloy the bracket is made from and find out if annealing it causes it to lose strength. On the other hand, if your friend routinely cooks aluminum in his oven, he may already know the tolerances.
Dave

Hey dave you ve got my concerns now.. I need to double check the oven temp... If have brought the 6061 to zero temper that might be a problem. What if i brought temp back up to 350-400 and let cool on its own.. Or can i bring thetemper back.. I am seeing the temper cut in half if brought to 775 degrees.. Do you anyone i can discuss this further in detail...

Unfortunately, my knowledge of metallurgy is only enough to get me in trouble. I had metal shop in High School (Stranahan class of '78) and the shop teacher showed us how to spin an ash tray out of aluminum sheet. It became work hardened and he used an oxy-acetylene torch to soften (anneal) it so he could work it some more.

In college, I took scuba to get my PE credits and they told a horror story about someone who had done a fancy baked enamel finish on their scuba tanks and the next time they were filled they exploded because the baking process had annealed the aluminum.

More recently, I read where a manufacturer of aluminum wheels (949 Racing) told a customer that he had voided his warranty by having his wheels powder coated.

So I don't know what temperature it takes to anneal 6061. It probably depends on whether the material was tempered or not. I'd start by asking the manufacturer of the bracket.
Dave

Bracket
 

After some reasearch,, the oven was set at the low end of the annealing .680 degrees The bracket was on top so maybe it did not get so hot cause the water spray to adjust temp and ash is at the top.. My guess... I did speak to a shop in jacksonville they do tempering.. He was very helpful on at what temp to bring the metal.. He said 960 once at 960 then quench in boing water. The bring back up to 360 for ten hours.. That should bring back to t6... If you skip the las t part of reheating.. Then it will be t4 .. If i brought bracket to anneall.. Or 0 then the strength is 18000 psi verse 47000 psi.tensile.... And shear is at no greater then8000psi verses25000
Elongation to failure at 15 percent... So i basiclly cut the strength to 1/3... The guy said he could try to temper it at a cost of 600... But cant gurantee that it will look like a bracket when done...
I am goin to go with the later and see what happends..

dave do you know what kind of forces are put on theses brackets?

Sounds like your metallurgy is enough to keep you out of trouble lol...yes it was tempured.. I saw on the angle that it was 6061t

Because I do things like this sort of analysis at work and if I were to say something else I shoulder some liability, I would have to say you need to either scrap it or find someone who can confidently identify the material and process it correctly.

But I would still say that, even if I didn't have to. What you did was sort of anneal the aluminum, assuming it is 6061. Which greatly weakens it, and it isn't clear what the path back to the original strength is. Not to mention the welds are pretty discolored, so that is suspect or at least worth investigating.
Solution heat treatment and artificial aging is different from annealing, and you are likely to wind up with a pretzel. That process involves a specific high temperature for a short time and a water quench, possibly a straightening, and then an artificial age at a raised temperature.

If you can be confident that there is adequate strength margin built into the bracket as originally built because it was welded and then never post weld heat treated, then that is up to you, but that argument doesn't seem sound unless you can get agreement from the manufacturer.

If you are really hanging 2 outboards off it, then to me the cost of a bracket versus two outboards makes for an easy decision from a financial risk perspective, let alone a personal safety perspective- it should be replaced with a known good bracket.

Sorry for the bad news.

You asked about this in my old aluminum bracket analysis thread. Which was made of a specific alloy made for welding and no post weld heat treat and no annealing, so it is pretty different.

Hey i appreciate the reply..i would never hold anybody liable for my mistake... Just needed some insight thats all. I will check with manufacturer. And hear what they have say...unfortunately for me as of right now it doesn't sound good..

Well looking for a bracket... But still not giving up yet on the other one... Checking oven range.. Going to try to temper tjis bracket... If it still looks like. Bracket when the quench is done then i will use it.. Stay tuned for an exciting event...
Anything has got to be more exciting then fairing the stern... That is where i am at now... Almost done.... Then off to primer545 and then a high build allthe way around....
Then545 and color.. Sanded hull and filled pin holes and scratches with lw fair.. By awl grip noticed a couple dry spot and delamination.. Of gel coat and mat.. Ground and filled with epoxy....
For the record.?" I WILL Never cut off another transom skin again.... not in this life time

I WILL Never cut off another transom skin again.... not in this life time


Lol. I hear ya there.

fairing Transom
 

You know it is sad when you and your straight line sander are on first name terms.. I am finally putting up my sander and laying some primer on her. Sat if weather permits... Need to hurry up Code Enforcement sent me another notice. Need to repeat I will not cut another transom skin off again.. All in all I got her pretty fair. I have decided to bottom paint cause of the tanins in my canal.. There always seems to be a scum line that I cannot clean off.

pics of the fairing LW epoxy
 

Ready for paint

Hull is all primed now ..ineedcto enclose engine bay and build a hatch .. how did you guys enclose one?...

deck inspection and replacement
 

Well I knew there were some bad spots around the t top legs so I decided to tear the top skin off and replace with foam core.. this is were I am at now.. I removed the tank and found some bad spots will weld them up as that is all about five little spots about 1.00" around... I am debating on removing forward box and moving tank far forward.

I will a agree a twisted wire cup brush on a grinder made the balsa core
come right off

If you're planning on twins on a bracket, I'd definitely move that gas tank as far forward as possible. The CG on the I/O's is further forward than on the OB models even when they were hung on the transom, so a bracket will move the CG even further aft. I'd prefer a couple of 50 gallon tanks so you can burn off fuel in the aft tank first, or not even use it except for long trips.

Inhave two 70 gallon tanks i can put in the boat but i will have to remove the fish box and loose storage.. When fishing i usually have a bout 200 pounds of fish and ice coming home.some times more.. Would that be enough .weight forwad. I have a bracket about 175 lbs and twin150 mercs 99 carb outboards...28 " setback Iwas going to move fish box to the stern. But then the weigt would be in stern. Here in pc we run 100 miles round trip to our fishing grounds.

Here is the rest of the glass skin pulled and played new scale of 1708 down then I vaxumm baggws yje foam down. My vac pump died while glassing so I had to improvise...

foam core
 

Here is the foam

Finally have fuel tanks blasted and coated with 5811 belzona immersion grade.. I first sanded with 40 grit and cleaned with ppg alum cleaner.. Then i white blasted all the seems and hard to reach areas.. Cleaned again. Let dry then coated with belzona... 3 coats on bottom. And three coats on top then 2 coats on sides.. Also finished coating alum transom bracket supports.. Once installed i can finish up the floor cause theses brackets bolt to the deck as well..

tanks
 

tank before and after

brackets for engine bracket
 

this stuff is very good at keeping corrosion to a min. I have used this in some of the most corrosive environments. Such as Large heat exchanger plates for Gulf power electric. and For all wastewater applications for coating of wastewater pumps. the pumps are cast steel and this stuff really protects these pumps from corrosion. Belzona can be used for concrete, steel and Alum..Oh and as far as elongation for expansion and contraction. It is excellent..