28 Roadster Door Rust Repair
 

So I bought an original 28 roadster door a few months ago and just got around to sandblasting it today. The door was very rust free and was complete with no rusted out parts (a rarity). Somebody painted it a green color, almost like they were trying to make a car john deere themed. Anyways, I sandblasted it and discovered some pin holes and slightly bigger holes on the bottom in the middle and along the edge. They do not affect the structural integrity of it because I put some pressure on it with my finger and it didn't budge. My question to you Ford Barners is how should I repair this? I am not an experienced welder, but I have a good friend who ran a body shop and could help. Or should I buy a patch panel?

Re: 28 Roadster Door Rust Repair
 

Welders can spray metal. It is a specialized service. Since it won't be seen you could reinforce the inside with fiberglass cloth and resin then use a bit of filler on the face.

Re: 28 Roadster Door Rust Repair
 

[QUOTE=J Franklin;1683739]Welders can spray metal.

Plz tell me more about this -- 'spray' metal
Thanks

Re: 28 Roadster Door Rust Repair
 

[QUOTE=rfitzpatrick;1683814]I think it is a device that melts metal and transfers it to the part needing filling. I have seen finished examples ( light buckets, door skin) and such at swap meets as a service from a vendor. You will need to search for more information.

Re: 28 Roadster Door Rust Repair
 

I am familiar with spray metal mostly used in motors and drives to make up tolerances so that bearing races and shafts can be made to fit.
I have never seen or heard of such being used for body work. There used to be a lead spray technique back when body lead was used.
The fix is totally dependent on what your want the car to be, how long you will keep it and what environment the car will travel and be stored in.
Rust holes you see such as yours usually means there are ten just like it waiting to break thru.
If you are building a driver, I would get some metal-bodied filler and cover them over.
That is a temporary fix but might last 5-10 years. The permanent fix is to put new metal panel in; don't know of anyone that makes an acceptable inner panel for that but easily fabricated

Re: 28 Roadster Door Rust Repair
 

If the car is going to be a driver and used offen, left outdoors, washed, driven in the rain. I would recommend replacing with metal. Cut it out, and put in new piece. Make sure to coat the inside very well or you will have the same problem again.

Re: 28 Roadster Door Rust Repair
 

I think that is what I will do considering I want to drive this A a lot and enjoy it. Another thing, has anyone else had to replace sheet metal but no patches are available like in my case? Where would you go about getting some sheet metal of the relatively same width?

Re: 28 Roadster Door Rust Repair
 

parts of an old car can be used go to a junk yard or to a welding shop and get the proper gauge metal. Some can be hand formed on a work bench with a 2x4. Correct gauge is important. I have the same problem. Will cut out a section that is bad and replace it with new metal

Re: 28 Roadster Door Rust Repair
 

JC Whitney used to sell metal relatively cheaply. dont know if they still do?

Re: 28 Roadster Door Rust Repair
 

That shape is common to most cars and trucks through out the years. I just go to the junk yard with my tape measure and find a door and cut it apart. Even if the main part is dented the bottoms are pretty straight.

Re: 28 Roadster Door Rust Repair
 

Here is what I did in my wife’s Tudor which had holes in the door bottom and 2 rust penetrationns in the outside panel very low down. I did not want to repaint the door after burning the paint with welding and I did not want rust to ever occur there again. So I phosphated the existing rust after scraping and vacuuming the recess to remove all loose matter and then pressure washing inside the door. I used an Ospho type product. I cannot remember which brand, but you want a “pure”phosphoric acid one containing a little surfactant to cut through any greasy or oily film, as opposed to one containing phosphoric acid and a water-based coating resin, which leaves a paint type protective film behind. This is because you are going to apply a 2 pack epoxy on top to encapsulate the area forever so that you could fill it with water and it will still not rust the coated part!
You need to buy a 50/50 resin/hardener epoxy with good film forming properties at room temperature. The resin part A's are all similar, but there are many hardener part B types – both in ratios used, temperature and time of cure, strength, temperature resistance etc. A room temperature, 1or 2 hour gel time (working time or pot life) epoxy hardener is what you want. A room temperature “laminating resin” system will be ok. A hardener known as “polyamide” is what I used.
Get the resin from a boat repair supplier. They are known as Ships Chandlers here in New Zealand. Or maybe look up “fibreglass suppliers” to find a source. Get an epoxy rather than a polyester, since epoxies have better adhesion and flexibility for this job.
While you are at the supplier buy some “fumed silica” (Aerosil is a brand name) to thicken the resin and make it anti slump so it will stick to the walls inside the door panel and not just run off into the bottom. You only need a few grams since it is very light and bulky.
Now put a good tape over all the holes under the door to hold the epoxy mix inside the door. Take equal parts of the hardener and resin ( by weight or by eye if you cannot weigh since it is not critical with a polyamide hardener) and before you mix them add quite large volumes of the aerosol powder to each until you like the consistency. They will take an amazing volume and still remain very resin-rich and sticky, compared to thickeners such as talc and chalk, which is why i did not suggest these. You want great waterproofing which fumed silica gives and talc, chalk etc will lessen.
Having both the consistencies right, mix the two components thoroughly and you have an hour or so ( less on hot days) to put a 1/16th or 1/8th coating over the holes and a nice skin on the walls inside the door. For a really badly rusted door bottom you can of course add a layer of fibreglass cloth, but this is deviating from the purists “100 percent real steel” approach. The resin layer I suggested is really only like very thick paint and permissible in even a high points restoration in my view.
After 24 hours remove the masking tape, smooth out any irregularities and coat underneath the door with a similar epoxy mix to keep rust at bay from outside the door. Remember to drill out the drain holes which you will have filled when you treated Inside the door, and if these were drilled through steel and not through resin in a rust hole, you need to coat the sides of the drain holes with epoxy as you coat underneath.
Buy some acetone for clean up as you go, wear some rubber gloves if you are a messy worker and either clean your paint brush in acetone or throw it away after use.
I confess to owning a resin manufacturing business in NZ and maybe making this sound complicated with the detail I have given but it is really very easy and satisfying if you cannot weld steel.
I can put in new steel, but welding is much more invasive of surrounding paint which gets burnt in the weld zone. A resin repair has no effect on surrounding paint, but work cleanly and do not use acetone on your good paint because it will attack lacquers, though not original enamel on fenders.
Remember this epoxy repair is very tough and not like Bondo. If you get it where it should not be -i.e. may be an “icicle” of resin hanging from a hole you missed and did not block with tape – you will need a grinder to get rid of it, not just 180 grit abrasive paper as with Bondo type fillers.
SAJ in NZ

Re: 28 Roadster Door Rust Repair
 

That resin sounds like bondo on steroids. I am weighing my options right now because I would prefer to never have to do this again, but then you have to put the time and effort in as opposed to just slapping some body filler over the rust holes with fiberglass cloth, which is of course not going to last and is 100 percent the wrong thing to do. It sounds like to fix the door forever I either need to cut out the bottom patch and replace it, or do what you said with the very heavy resin to seal the rust in.

Re: 28 Roadster Door Rust Repair
 

You said you have a friend that's a Bodyman. This is a standard repair. Need a door bottom made up and put in. The tricky's parts is opening up the lower lip. If it's solid, it shouldn't be a problem. If it's weak then it will need a outer panel as well. Pretty standard stuff. A days work on the metal. JP

Re: 28 Roadster Door Rust Repair
 

Chrs1961815, You mention "sealing the rust in" . The purpose of the phosphoric acid is to convert the rust to black iron phosphate. The rust is gone, not sealed in, and the phosphate surface is passivated and resists re-rusting. This is the similar to the "Parkerising" process used on Fords before painting and on most other new body work even now.
SAJ in NZ

Re: 28 Roadster Door Rust Repair
 

That is what I meant :)