Large Scale Central

Aging the 'tin'

The MIK - Annual Build Challenge
#1

I got permission from Dave to experiment with a surface/aging treatment for our tins. The condition being I share the results and these pieces won’t see the contest.

I tried my usual resist … last time I tried this it was 30 years ago… the sharpie proved worthless…

Back when Radio Shack was everywhere it was easy to get the Archer Echtant, but heck I couldn’t even find our 2 remaining stores.

On line I found a DIY echtant made from available chemicals. Hydrogen peroxide and muriatic acid. Don’t breathe the fumes.

I didn’t like the lack of control, dropped into the solution and it ate where it was hungry … but I did get some interesting results and I’m thinking of an eye dropper to paint the etch where I want it.

I had a bowl of water and baking soda and another of water for rinses. If you don’t neutralize the acid, humidity can cause further action.

The tin with the resist is far right, the shiny parts on the others were not immersed. The see through parts are very thin and would need backing. Adding rust paint may be enough.

The formula called for 2 parts H/P and 1 part MA. I ended up using 1:1 because my container was too small.

Always add acid to water. Sing along; “Do like you oughter, add the acid to the water.”

Hydrogen peroxide 3% (Oxygenated water)

Muriatic Acid, try to get it at a hardware store, you’ll only need a quart, at the pool supply it came in a 2 gallon box. I have other uses for it, so I got the box.

The sun was out when I did those, when the clouds came out, I went in. There is snow on the foothills behind me… kinda cold for a desert rat.

Dave told me of another method where they sprayed on cheep oven cleaner… to give it tooth. I noticed tooth before it went gray.

John

#2

John,

Are the holes from it being eaten through? Or did they start out that way? I want it to look aged not disintegrated. How long are you soaking them before taking an Alkaline bath? I love the looks of the flat grey and looks toothy, how did the oven cleaner fair compared to these?

Thanks for doing this, I was wondering myself how to do it.

Devon

#3

Hey, I got some blackening solution for aluminum from Jax Chemicals. Tried it out on my aluminum hand car wheels. They looked more rusty and dirty than blackened which might be perfect. I’ll toss a bit of flashing in to see what happens.

#4

Hi Devon,

The holes are eaten through, I wanted the rusted out look. ‘There ain’t nuthun’ new on my pike!’

These were scrap tins from Dave, same size and condition as the contest pieces. (except for dings and groove imperfections) I did try burning the end of one in case there was a coating. I didn’t see a change, I used a ‘torch’ lighter for the intense heat.

Time is dependent on the temperature of your mix. The solution got faster with dissolved aluminum in the sauce… a guesstimate 5-10 min to get an even grey.

I have Stainless tweezers, I dipped the piece and lifted it out with a puddle on the tin. Rocking the tin I watched the bubbling brew as the acid consumed itself.

Tomorrow I’ll experiment with paint resists to get a more airy look. I want a lot of little holes …

I didn’t try the oven cleaner, others have, hopefully they will chime in.

John

#5

This is about what I’d like it to look like if I was modeling something old. In my case I may just let it weather naturally so it matches the station it will sit next to.

#6

So 5-10 gave an even grey but not the burned through areas. How long to burn through (others might want to know)? Also do you think something applied to the aluminum would prevent the acid from eating certain areas (is that what your calling a resist?).

#7

Interesting, I have some PCB etching solution somewhere. I have heard of it being used for this, but I have never tried it.

#8

I would try soaking one in really strong tea and let the acid and tannins do their thing for a while.

#9

Todd; To each his own.

David; I heard the same thing and tried it. Archer Echant mentioned in the first post is that pcb stuff.

Devon, If you watch it, there is plenty of time to remove, neutralize and rinse before it gets thin. It is tricky when the holes ‘flash’ open. Have the rinse w/ baking soda close. My tweezers lock and were not affected by the acid, with practice I want to be lifting as the flash begins … You can play with the concentration. Start with 2HP 1 MA

Yes ‘resists’ are applied to resist the etch. Way back when, the Sharpie was effective with Archer (Radio Shack brand name) Echtant, tomorrow I will try paints and glues. A sharpie comes off with alcohol. The best resist will dissolve in a dis-similar liquid because the etching weakens the metal. The acid solution is water based maybe a cured white glue will hold for the duration. Paint/thinner and other inks/alcohol…

John

#10

my flashing experiment with the JAX Aluminum blackener worked kinda… the flashing sample I had actually seemed to have some kind of coating on int. I sanded it off with 320 grit wet-dry that I had lying around and tried again. it did blacken the aluminum when dipped into the solution. the solution is probably stronger than out of the bottle because it has been lying around in an open yogurt container since I did the wheels after Christmas. with the coating removed the solution certainly did blacken the aluminum but after rinsing with water it largely wiped off with my cloth while drying it. though it is still darker than the bright aluminum. looks like older but still good galvanized metal.

#11

If you don’t mind me jumping in I will say that etching solution works very well but you have to really watch what your doing. If you do use it do it outside as the fumes are nasty. When you submerge the aluminum sheet in the solution it looks like nothing is happening then all of a sudden it is eating it up, so have a soda dip tank handy to stop the reaction.

A few pictures of some results.

A couple of barrels made from aluminum but similar results to the roofing

I have even oversprayed the dipped sheets with a little “Cold Galvanizing” before weathering

It ads a different effect.

Sorry the pictures are so small but they are what I had on hand.

Thanks for your time

Rick

#12

Do people realize that if the panels are aluminum, as opposed to tin from a can, sodium hydroxide will eat right through them in no time?

When I visited the Boeing factory and watched them make airplanes, they would mask off the aluminum skin and dip the body panels in huge vats of caustic to make the windows and holes.

I also met a guy who fell in a vat at one time. (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-yell.gif)

#13

Poor guy!

I’m using a diluted HCL acid, I like the time I do have. I can see how it would be faster than punching out those holes.

And no, I’m acid illiterate… I used what was suggested.

John

#14

Has anyone tried vinegar for weathering? Years ago I suspect it would have worked fine but at the rate everything is diluted anymore I doubt it would do anything!

#15

Doug that’s next, today I tried using steel wool as an applicator hoping for rust with the enchant. Nothing, the steel didn’t react at all.

The next is to dissolve that steel in vinegar, I know that makes a rust stain for wood, I’m hoping for a chemical bonding, but most stains on metal wipe off.

John

#16

I just learned a week ago that vinegar and and Hydrogen peroxide at a 1:1 is used as a PCB enchant. It will also mildly etch a penny. I was going to try this before the Muriatic acid so let us know. I would think it would be slow but that isn’t such a big deal. Maybe even better if all your looking to do is etch it and not eat holes in it.

#17

Devon Sinsley said:

I just learned a week ago that vinegar and and Hydrogen peroxide at a 1:1 is used as a PCB enchant. It will also mildly etch a penny. I was going to try this before the Muriatic acid so let us know. I would think it would be slow but that isn’t such a big deal. Maybe even better if all your looking to do is etch it and not eat holes in it.

But I am looking to make holes, but I keep getting big sections going at once. I was getting some nice lacy see through that would disappear at 5’ so I kept going.

It’s been too cool here to stay out long. I’m trying the steel in vinegar next, why don’t you try those things you like?

I’ve got a PET CT scan tomorrow and we begin the next day… don’t wait for me … suddenly you have more time.

John

#18

good luck, John

#19

I just got mine today. I will throw a piece in vinegar and H2O2 and post here,

#20

Korm Kormsen said:
good luck, John

Thanks Korm,

If this one is clear my Doc gets to declare me Cured (from the cancer). I feel sorry for her, there’s only a 15% success rate, but real happy for me!

John