UNCLE LAR'S WORKSHOP
    
 
 

 
 

ASK UNCLE LAR Treating Rusting Tin

`Problem at hand ... I purchased a nice size piece of old flat
tin...building was over 100 yrs when it was torn down...this piece is
a bit rusty...it has a wood frame on the back so I can hang it on the
wall...problem...how do I keep the rust from continuing...I really
hate to spray or paint it with shellac...hubby says it won't rust any
more unless it gets wet...which it won't.

Any help is appreciated.
Thank you,
Rutti

 

Hello Rutti, 

Tin will continue to rust until you place a barrier between it and air, due to moisture in the air. Tools rust in tool boxes, saw blades get covered with rust, and none of these items have ever been wet. Check the rust prevention sprays available from top hand tool manufacturers. Rust prevention is a big market. I try to keep a coat of wax or WD-40 on all my tools to prevent this. I always use a dehumidifier in my shop for this reason.  

Now, to further expound on your question. You have several ways to go. Your objective is not to remove the rust, but only the surface of the rust. You do not want to scratch through to the metal under the rust.  

  • If you choose to coat the item with wax, a good choice if it is only for display, put a coat of wax over the entire item. Any good paste wax is fine, but don't use one with a cleaner in it. Gently rub the waxed rusty area, before the wax dries, with the fine wet or dry sandpaper, 220 or finer. The wax helps to lubricate the sandpaper and prevent it from scratching though to the metal below, and protects the adjacent non-rusted area near the rusted area. Now wipe off the wax and rust that you sanded loose and polish the whole surface. In most cases this provides adequate protection. If it's too shiny for you, just reapply the wax very thinly and leave it, or, polish it very lightly until it has the sheen you desire. In the future, it may have a little dust adhere to it, but all you need to do is wipe it off.

  • I tend to stay away from mineral oil because it is hard to wipe off and makes a great dust collector.

  • WD40 is thinner and soaks into the rust for protection. It is also a good lubricant for sanding or buffing with steel wool or 3-M pads. WD40 is my choice for cleaning and preserving antique tools that have rust on them.

  • I use wax on tools that I use regularly as oil can stain the wood and/or cause a finishing or staining problem if it gets onto the wood. Sometimes this isn't apparent until you stain and wonder why an area is lighter than another.

  • Shellac is another decent choice for display items. It produces a great, long lasting barrier . Shellac is used to coat pharmaceutical pills, candies and many foods to help them hold shape and keep air away from them.  

You should never do anything to an item of value that can't be reversed. For example, wax can be removed with mineral spirits or naphtha without doing any damage. Shellac can be removed with alcohol. Oil, too, can be removed with naphtha.

If you have a very small area of rust, an ink eraser will easily remove it. Then put a bit of shellac or wax on the spot for protection. Best would be to put shellac on the rust area then wax the entire surface. It should remain trouble free and protected for years.

 

Uncle Lar

UncleLar@TheCollectorOnLine.com

 

 

 

NOTE:

Any information provided here is primarily based on my experience. While I can't guarantee you will obtain the same results, the various procedures should work for you if you follow the precautions before attempting them. For example, determine the type of finish that currently exists before starting any procedure. Always determine the stability the existing finish. If is flaking, it is unstable and either needs to be left alone on a valuable item, or amalgamated or removed if it is a piece that will have a greater value if restored and refinished.

This brings up a very important issue. TV programs such as the Antiques Road Show increase people's awareness that not everything should be restored, and that in cases of valuable items, it will decrease the value considerably. Now, the hard question to answer-what should you leave "as is"? If you are in doubt, contact an expert, knowing that he may charge you several hundred dollars to evaluate the piece. If you buy regularly from a knowledgeable antiques dealer, he may give you an opinion for little or no cost. If the item is one you see at most antique shows and shops, you can bet it is safe to restore it yourself. If it is something you've never seen, and you don't want to hire an appraiser, look for it on the internet and at the public library.

I can tell you some things I don't think you should strip and refinish. These would be furniture with its original paint, even if it is almost half missing. Usually these will be primitive items such as pie safes, cupboards,tables and chairs. Also, the wood beneath the paint will most often be pine, poplar or a mixture of woods.