Extremely pitted rust on Baby Bear, need advice on removal technique. This one is challenging.

[turn_n_burn]

Haven't been on this forum for almost a decade. Good to be back!
I have an old Fisher Baby Bear that has been used since about 1979, and it has some rust problems. It seems like there are 2 different kinds of rust on this thing. The outer layer comes right off with a wire brush or wheel. No big deal. Then, I also have this pitted-type rust that seems about impossible to remove with my cup wire wheel on my angle grinder. It would take me a week to get down to the metal working on an area the size of a playing card. Is there a better method to removing this kind of oxidation or some technique I should be using? These are some extreme close-ups of the rust after a good half hour of wheeling. I'm trying to get to a place where I can paint or paste the stove again. Any advice would be helpful. The first picture was taken with flash, so it's kind of exaggerated on the color scale. That pic also contains the area I worked on for a half hour.

 

[stoveliker]

Sandblasting?

 

[BillBurns]

An E Tank might do it ,but the size is the problem.

 

[Newbie78]

flap discs, then maybe acid.

Maybe there will be a welder along soon..

 

[turn_n_burn]

This is the downside of being a new user of wire wheels on an angle grinder. This little bastard was just pulled from my leg, where it has been residing for hours since I was working this morning. It was buried about 3/4 of the way in at apparently about a third the speed of sound, and I had no idea until I brushed it against something just now. The right side of it still has schmutz from my leg juice on it. Oops.

 

[peakbagger]

Sandblasting will definitely work with the right grit. The problem with any method is the surface is not going to be smooth. It will still work fine but its not going to be pretty. If you see those car restoration shows on cable where they rebuild a car quick they usually skip over where someone is applying bondo with a drywall trowel to fill all the low spots and then use a big air sander to make it look smooth. That may work on a car but with a stove anything you put in there to fill in the low spots will quickly pop out once its fired.

 

[turn_n_burn]

Sandblasting will definitely work with the right grit. The problem with any method is the surface is not going to be smooth. It will still work fine but its not going to be pretty. If you see those car restoration shows on cable where they rebuild a car quick they usually skip over where someone is applying bondo with a drywall trowel to fill all the low spots and then use a big air sander to make it look smooth. That may work on a car but with a stove anything you put in there to fill in the low spots will quickly pop out once its fired.

Is it even worth trying to restore with all that?

 

[peakbagger]

It comes down to do you want a "pretty stove or functional one? You can blast a lot of meat off a 1/4" steel plate and still have plenty of thickness left to use it as a stove. Stove paint tends to be flat so the divots will be less noticeable.

 

[EatenByLimestone]

60 grit, then 80 grit, then 100 grit, until smooth. I'd go more towards function over looks and acid treat it, then spray it. Itll have scars, but what doesn't at that age?

 

[brenndatomu]

You want to eliminate the rust, or fill in the pits?
I doubt there is anything you can do for the pits, but if you just want to paint it, stop the rust, and make it look better, POR15 high temp is good stuff...just knock the loose rust off and have at it.

High Temp

Purchase POR-15 High Temp extreme heat-resistant paint online now! This coating can withstand extreme temperatures up to 1200°F and will resist UV, cracking/chipping.

por15.com

 

[MongoMongoson]

It will look fine painted with the pits. They are just texture and character.

For a while I did not have a chimney cap above my Quaker, and when it rained or we had snow melt I could get water on top of it. It pitted pretty badly. I cleaned off the rust and painted it after the chimney cap was installed. It looks good, just not smooth.

 

[blades]

You can use one the rust removers on the pitted area just follow directions as to clean up neutralization . If you want to get fancy acetylene torch & brazing rod, can't use lead or solder to low a temp melt. Brazing rod in the 800-1000 deg area. Could be done with tig rig also. Tig would be faster and more localized heat. Little bit at a time so you don't warp things . Bit of an art in itself. In the old days we used lead and a torch on the cars. ( No Bondo back then) more art work.