Re: Newbie Rebuild Questions
Cad (Cadmium) is a heavy metal that the body is very slow to excrete. It is Carcinogenic is easy to inhale if powdered (like if you sand it when it is flaking! DON'T!!!). When I was doing plating engineering for the Navy we switched almost all of the Cad we were doing for IVD Aluminum which is a vaporized aluminum that was electro-deposited in a vacuum chamber. It was MUCH safer and worked just as well as the CAD. Problem is I doubt that even after 30 years I would bet it still isn't available in the small plating shops. The other nice thing about IVD Aluminum is there is no post plating baking needed.
I am pretty sure that a lot of the small shops still can do Cad plating if you want to re-do them and they have the equipment to put a reverse current through the wires to electro strip the old stuff off, then re-plate them. If you go that route you have to be ABSOLUTELY SURE they do a Hydrogen Embrittlement relief of the wires as SOON AS THEY COME OUT OF THE TANK! Most of the small shop owners I worked with just laughed at the requirement, but for high strength steel the wires WILL CRACK if you don't relieve them. This is a NON NEGOTIABLE and I would want to BE THERE when they pulled the wires to INSURE they were done right.
Within 30 minutes of removal from the plating bath the wires have to be in a 375 +/- 25*F oven and must stay there for 23.5 hours (we took off 30 minutes to allow a next batch to go in, the time was actually slightly shorter, but I don't remember how much and we used 23.5 hours). That 30 minutes from tank to oven is used to thoroughly rinse and dry the wires, NOT TO EAT LUNCH! Also the oven is ONLY for plating relief! Tomato fumes from the Pizza yesterday will corrode the wires and the Cad residue inthe oven on the Pizza will potentially KILL THE PLATE SHOP PEOPLE! Yes, we DID catch a guy heating his lunch up in the oven. Ever heard you can't fire a civil servant. It isn't true, he got fired.
Now, for what I did on my wires. They were NOT flaking, but I put a light coat of clear paint over them so they wouldn't. Not sure if it was legal, but if there are any FAA inspectors who don't like it, I made that part up.
As for welding. I took my 45 fuselage to a guy who TAUGHT welding at the ship yard for Nuke Subs and I swear he could weld two 2x4s together. He can weld anything from a Coke can to a battleship hull with anything from an Arc Welded that could explode your garage to a Zippo lighter. Best welder I have ever seen.
ABSOLUTELY agree about organization. Take pictures EVERY DAY of everything you take off and log and tag EVERYTHING. If a part you remove is pure JUNK, KEEP IT ANYWAY. It will be easier to repair it that to make a new one from scratch when you find out it is the one #$&%@(*&* thing no one here has. Zip lock plastic bags and a felt tip marker are great.
I have attached a photo of the access panel I put on the fuselage by the strut attach. Works great and i look at the longeron every annual, even if I don't need to.
On the ribs, Ray Bossola blasted his ribs with a Soda Blaster and primed them with self etching primer. If anyone knows more about the wash primer please post it. I bought one of the Soda Blasters, but I really like the idea of an Anodize look instead of the primer color and anything to get a few more ounces out has to be good.
Hank
Remember, POST PICTURES! The guys here are really good at spotting little things you might miss.
Cad (Cadmium) is a heavy metal that the body is very slow to excrete. It is Carcinogenic is easy to inhale if powdered (like if you sand it when it is flaking! DON'T!!!). When I was doing plating engineering for the Navy we switched almost all of the Cad we were doing for IVD Aluminum which is a vaporized aluminum that was electro-deposited in a vacuum chamber. It was MUCH safer and worked just as well as the CAD. Problem is I doubt that even after 30 years I would bet it still isn't available in the small plating shops. The other nice thing about IVD Aluminum is there is no post plating baking needed.
I am pretty sure that a lot of the small shops still can do Cad plating if you want to re-do them and they have the equipment to put a reverse current through the wires to electro strip the old stuff off, then re-plate them. If you go that route you have to be ABSOLUTELY SURE they do a Hydrogen Embrittlement relief of the wires as SOON AS THEY COME OUT OF THE TANK! Most of the small shop owners I worked with just laughed at the requirement, but for high strength steel the wires WILL CRACK if you don't relieve them. This is a NON NEGOTIABLE and I would want to BE THERE when they pulled the wires to INSURE they were done right.
Within 30 minutes of removal from the plating bath the wires have to be in a 375 +/- 25*F oven and must stay there for 23.5 hours (we took off 30 minutes to allow a next batch to go in, the time was actually slightly shorter, but I don't remember how much and we used 23.5 hours). That 30 minutes from tank to oven is used to thoroughly rinse and dry the wires, NOT TO EAT LUNCH! Also the oven is ONLY for plating relief! Tomato fumes from the Pizza yesterday will corrode the wires and the Cad residue inthe oven on the Pizza will potentially KILL THE PLATE SHOP PEOPLE! Yes, we DID catch a guy heating his lunch up in the oven. Ever heard you can't fire a civil servant. It isn't true, he got fired.
Now, for what I did on my wires. They were NOT flaking, but I put a light coat of clear paint over them so they wouldn't. Not sure if it was legal, but if there are any FAA inspectors who don't like it, I made that part up.
As for welding. I took my 45 fuselage to a guy who TAUGHT welding at the ship yard for Nuke Subs and I swear he could weld two 2x4s together. He can weld anything from a Coke can to a battleship hull with anything from an Arc Welded that could explode your garage to a Zippo lighter. Best welder I have ever seen.
ABSOLUTELY agree about organization. Take pictures EVERY DAY of everything you take off and log and tag EVERYTHING. If a part you remove is pure JUNK, KEEP IT ANYWAY. It will be easier to repair it that to make a new one from scratch when you find out it is the one #$&%@(*&* thing no one here has. Zip lock plastic bags and a felt tip marker are great.
I have attached a photo of the access panel I put on the fuselage by the strut attach. Works great and i look at the longeron every annual, even if I don't need to.
On the ribs, Ray Bossola blasted his ribs with a Soda Blaster and primed them with self etching primer. If anyone knows more about the wash primer please post it. I bought one of the Soda Blasters, but I really like the idea of an Anodize look instead of the primer color and anything to get a few more ounces out has to be good.
Hank
Remember, POST PICTURES! The guys here are really good at spotting little things you might miss.
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