Raising a dent in brass head plate?
-
- Frequent Board Poster
- Posts: 51
- Joined: Tue Oct 17, 2006 10:09 am
- Location: Hannibal, MO
Raising a dent in brass head plate?
I recently purchased some nicely polished brass reels and the headplates were dinged in shipment. Any suggestions for raising small dings? I had thought of using a smooth nylon or hardwood rod tip and rubbing from the backside while the face was placed on a sheet of glass. Help?
- john elder
- Star Board Poster
- Posts: 8553
- Joined: Mon Sep 22, 2003 2:44 pm
You can try that, HM, but i'm guessing that after about 10 minutes of rubbing, you'll be looking for Plan B. I would tape the face to keep it from getting scratched, then put it face down on a flat surface.. piece of hardwood or sheet of brass. Then put a flat piece of hardwood over the back side of the dent and gingerly tap down with a hammer. Check frequently to see how you're doing by rubbing your finger over the dent. If progress is nil, reduce percent Ginger until the dent is flat. Just watch that you aren't putting in a "reverse dent" with the wood block.
You can use a smaller punch to do this, but the smaller surface area making contact with the back of the dent will increase markedly the likelihood of doing damage from the back side.
hope this is a help!
Oh, and..
For Steve and Brian:
http://www.thefreedictionary.com/gingerly
You can use a smaller punch to do this, but the smaller surface area making contact with the back of the dent will increase markedly the likelihood of doing damage from the back side.
hope this is a help!
Oh, and..
For Steve and Brian:
http://www.thefreedictionary.com/gingerly
-
- Frequent Board Poster
- Posts: 51
- Joined: Tue Oct 17, 2006 10:09 am
- Location: Hannibal, MO
Thanks!
I like the reels, but the dents sure stand out. I will try tapping from the back side on a level surface. Any other ideas?
-
- Ultra Board Poster
- Posts: 1637
- Joined: Thu Oct 09, 2003 2:22 pm
- Location: Salisbury, NC
-
- Big ORCA Fan
- Posts: 14
- Joined: Tue Apr 22, 2008 2:55 am
The trouble lies in the way an inward (or outward) domed dent is produced. A curved surface has a greater area than a flat one, so the original impact has stretched it a little thinner. To reverse the process properly, you have to thicken it up again. It takes very well directed force to do this, without letting it take the easier course of moving the surplus to a dimple somewhere else.
It's a big help if you have another endplate, identical to the one you want to work on. There are bismuth alloys which melt at temperatures of about 160 degrees fahrenheit, and you can use one of these to cast a perfectly fitting internal mould of the good endplate, to put inside the dented one. It is probably hard enough to use as an internal anvil, but if you like, you could put a broken fragment of utility knife blade between anvil and dent.
The best alloy is sold by www.brownells.com the gunsmith supplies house as cerrosafe, or by plumbers' suppliers as cerrobend, for putting inside a pipe to bend it without buckling. I think the same thing is sold in the UK as Woods metal. There are metals of similar melting-point sold as low melting-point solders, but I think they might have more tendency to bond to the metal. I would smoke the inside with a candle flame before using these.
It might also help, when working with unplated metal, to spot anneal the area of the dent. A large electric soldering iron or a very small pencil blowtorch flame will do this, leaving work-hardening in the parts you want to stay tough. A very cost-effective tool for this and many other jobs, and convenient to feed, is a miniature blowtorch which you refuel from an aerosol-type cylinder of lighter gas.
It's a big help if you have another endplate, identical to the one you want to work on. There are bismuth alloys which melt at temperatures of about 160 degrees fahrenheit, and you can use one of these to cast a perfectly fitting internal mould of the good endplate, to put inside the dented one. It is probably hard enough to use as an internal anvil, but if you like, you could put a broken fragment of utility knife blade between anvil and dent.
The best alloy is sold by www.brownells.com the gunsmith supplies house as cerrosafe, or by plumbers' suppliers as cerrobend, for putting inside a pipe to bend it without buckling. I think the same thing is sold in the UK as Woods metal. There are metals of similar melting-point sold as low melting-point solders, but I think they might have more tendency to bond to the metal. I would smoke the inside with a candle flame before using these.
It might also help, when working with unplated metal, to spot anneal the area of the dent. A large electric soldering iron or a very small pencil blowtorch flame will do this, leaving work-hardening in the parts you want to stay tough. A very cost-effective tool for this and many other jobs, and convenient to feed, is a miniature blowtorch which you refuel from an aerosol-type cylinder of lighter gas.