Jump to content

Radiator Shell Repair Methods & Question


Guest Mochet

Recommended Posts

Guest VeloMan

A while back, I inquired how to repair a dented radiator shell without de-soldering it from the radiator. Yesterday, while reading "Antique Automobile" July/August 1981, I found a "Restoration Tips" article by Tom Reese. He pulls dents by making a small dent-puller with a 1/4" rod threaded for a nut on one end and a drilled-out steel cylinder which slides up & down the rod. He solders the rod (the end of which has a groove cut around its circumference to better grip the solder) to the dent, the pulls it out with the sliding steel cylinder. Eventually, the unevenness is smoothed with files, sandpaper and buffing.

He goes on to fill an "un-pullable" crease with braze. My question is: what brazing rod will match a brass radiator shell? Another question: Is Tom Reese still with us?

Phil Jamison

Link to comment
Share on other sites

You should use filler made from a hidden donor area of that shell if possible. If you can't, I'd look for some damaged brass parts from about the same age and do a test. There are just an infinite amount of "brass colors" due to different mixes of alloys.

Also, before you try pulling dents; read up on "annealing brass" as well as "work hardening" (avoiding)

Link to comment
Share on other sites

Guest VeloMan

The Autozone-type puller (which is designed to screw into drilled holes) might be a bit heavy for the rather delicate work pulling on the brass shell. For some reason, Tom used 1/4" brazing rod for the shaft. Perhaps he assumed it would hold better in the solder(?)

F&J: I didn't know you could melt regular brass to fill dents in brass. I assumed brazing rod has a lower melt temperature so you don't vaporize your project.

Phil

Link to comment
Share on other sites

Repairing with braze is far more difficult than it sounds. I would suggest using a high silver content silver solder which is almost undetectable if the part is kept highly polished. Very difficult to fill a depression with braze without the braze becoming porous. Also a very high risk of melting a hole thru the shell before the brazing rod gets hot enough to flow. Possible but difficult.

Link to comment
Share on other sites

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: VeloMan</div><div class="ubbcode-body">

F&J: I didn't know you could melt regular brass to fill dents in brass. I assumed brazing rod has a lower melt temperature so you don't vaporize your project.

Phil </div></div>

I have never tried it. I used to read all the old magazines years ago, and do recall reading about it on early brass car parts.

If there are no sharply creased dents, you should be able to use that solder/dent puller without needing any filler.... But I would not use a slide weight. Just pull on the rod with visegrips, and you can actually slightly change the way it pulls the dent, by pulling the rod at different angles. That is helpful if the dent is odd shaped. Once you try it on a scrap brass part, you will get the hang of it. Often, you will need to hold slight upwards pressure on the rod while gently tapping a high spot right close to the inward dent.

The anealling is very important to do first.

Link to comment
Share on other sites

More info;

Bear in mind that if you have a 2" long dent, you can't just start pulling in the center, because you will end up with a nasty high spot while trying the get the outer parts of the dent to move.

You need to reverse how the dent was made when removing the dent. So, you need to work the outer parts first, and the center impact point is last.

I would start with the smallest dent you have, and if that dent is dime sized or less, you might get it out with one pull point. Do this in good lighting so you can see if anything is getting stretched as you pull by hand pressure.

Sometimes you will see the surrounding areas coming up too much, and this is where you need to lightly tap all around the pull point. More often, you need to tap the outermost crown of the dent all the way around while applying pressure.

It's lots of practice and skill to do true "metal finishing". A botched job will stick out like a sore thumb, and a few original dings sometimes are rarely noticed.

You also should not gob lots of solder on the pull point, as you won't be able to see what's going on. I'd tin both the dent center and then wipe it off, tin the pull rod end and use just a small blob of solder on the rod.

Use a very fine file to check for low/high spots. You don't want to remove any metal at this point; the file is just a vision tool. Actual filing is the last step when the metal is quite flat. You just don't have much thickness to do a lot of filing.

Link to comment
Share on other sites

Guest VeloMan

Good tips. I especially like the annealing suggestion. I've been reading about it, and it looks like a useful technique for brass. Hopefully, one can anneal certain portions of the shell and not the entire thing. Otherwise, the solder holding it to the radiator will melt.

Here's a good web page on the annealing process for brass, as used in reloading rifle shells, but applicable for radiator shells: http://www.6mmbr.com/annealing.html

Phil

Link to comment
Share on other sites

Guest VeloMan

To answer my original question: Tom Reese is still around. He wrote to me from Arizona. He contributed many interesting technical articles for "Antique Automobile" over the years, and it was nice to hear he's still out there cranking!

Phil

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...