Total noob cast iron restorer process

[RobbieTimber]

Hello great Hearthers

What do you think of this to prep before painting:

Steps
1) Light wire brush scrub
2) Electrolysis
3) Light wire brush scrub
4) Ospho acid spray
5) Light wire brush scrub
6)Repeat any of above if needed
7) Lacquer thinner wash [wire scrub if needed]

Am using those cheap silver drill bit attachments for the wire scrub. Seems to work well.

 

[begreen]

Sounds like overkill. What is the stove and what condition is it now?

 

[RobbieTimber]

Varying conditions of rust and soot, and I'm able to get it nice and clean, however it did take all of those steps (maybe the pre-electrolysis scrub can be skipped if they dont start too dirty)

Main goal was to ensure the paint job lasts long, and I read you have to get the Ospho off

After Ospho dries, there's decent amount of black bubbly (iron?) and/or black soot/carbon -- which does require scrubbing with either the wire cup or maybe a plastic abrasive pad if not too bad

After the ospho, there's powder on there (im keeping it all dry now to prevent rust) so the idea was lacquer at the end, then paint!

Thought to do lacquer first to get soot off first, but, wire brush + electrolysis seems better approach (want to minimize solvent use)

I want to be thorough and to the dot on this. Not overkill so any advice always appreciated thanks

 

[stovelark]

Wow- never did a chemical process for repainting. Just clean off rust and repainted. Any matte black paint will usually need to be repainted every couple of years if you want it to look new. Baked in paint tends to gray out gradually, sometimes we don't notice it due to it being gradual. Your completeness of the process is noteworthy, but not practical for most just wanting to update the stove's look. Stay warm.

 

[RobbieTimber]

lol! can see why it might be overkill now.

after the electrolysis and scrubbing, its bare so it gets flash rust.
nice to spray ospho to neutralize that, and protect to ensure no future rust, before the laquering and painting (is the idea).

thought to not scrub after the ospho and just go to laquer, but, the ospho leaves visible white dust and some black crudge like welding slag that needs scraping. either from iron, paint, soot (on the outside), or any/all.

it's time consuming, these are all dirty and need care so going all out. nice that its a small reginald because they can be moved easily

thanks for the input

 

[bholler]

lol! can see why it might be overkill now.

after the electrolysis and scrubbing, its bare so it gets flash rust.
nice to spray ospho to neutralize that, and protect to ensure no future rust, before the laquering and painting (is the idea).

thought to not scrub after the ospho and just go to laquer, but, the ospho leaves visible white dust and some black crudge like welding slag that needs scraping. either from iron, paint, soot (on the outside), or any/all.

it's time consuming, these are all dirty and need care so going all out. nice that its a small reginald because they can be moved easily

thanks for the input

Is this for a wood stove?

 

[RobbieTimber]

Yes Reginald 101
Needs to be functional and beautiful, lasting without paint bubbling, fully re-sealed, new gaskets.

Moderately rusty. Some fasteners rusted, some plates stuck etc.
Good reason to try out electrolysis (and also thought maybe easier than scrubbing moderate rust).

Got intrigued by a nice glossy paint job, and want to ensure the paint sticks

Electrolysis: rust
Ospho: flash rust (maybe soot?)
laquer thinner: residue rinse pre paint
primer/color/clear thermalox

 

[bholler]

Yes Reginald 101
Needs to be functional and beautiful, lasting without paint bubbling, fully sealed, new gaskets.

Moderately rusty. Some fasteners rusted, some plates stuck etc.
Good reason to try out electrolysis (and also thought maybe easier than scrubbing moderate rust).

Got intrigued by a nice glossy paint job, and want to ensure the paint sticks, also now 3 reginalds in, 10-15 hours driving, plus busted 602C Jotul, and at about $700 in tools, gas, and craigslist prices to accumulate these.

The Reginald's were $100 each, the Jotul $150.
One is a Reginald 100 which is wider and boxier than the 101s, but has a busted back plate - can't find a replacement.

Jotul has busted back plate (replacement only $100).
Needs side plates, ($70 per).
Could go for $500-$1000 painted and refurbished, also, its quality

These things are fun - so small seems hard to find small european stoves in the USA

The jotul weighs almost 2x the reginald, with the same design!

What lacquer are you using that will stand up to the heat?

 

[RobbieTimber]

Sorry it'll be Laquer Thinner as a solvent to rinse residual grease, metal, ospho 'powder' and graphite [from electrolysis] prior to painting. Could skip and get away with it but this stuff is cheap. Mostly a hassle to use (toxic, fumes, flammable, solvent)

Lacquer Thinner - Klean Strip

kleanstrip.com

Most paint instructions for high heat stoves say mineral spirits leave residue - to only use laquer thinner for prepping to paint:

"How should I remove oil or other harder to remove contaminants?​

For oil, grease, graphite, or other hard to remove contaminants, use lacquer thinner, toluene, or acetone.​

Do not use paint thinner or mineral spirits as these products leave residue."​

Edit: That product above still has 1-5% Hydrotreated light distillate (petroleum, mineral spirits). So it does contain mineral spirits but the paint companies say laquer thinner is ok. If the bottle says 'Mineral Spirits" don't get that.

By the way, there are environmentally friendly laquer thinners containing *no* mineral spirits:

Some of the environmental ones contain acetic acid, some don't. The one above doesn't.
(You have to check the safety sheet documents online for the ingredients list).

Since the wire brush electrolysis got these clean, might just use the environmentally friendly version. That green envy one contains acetone, methanol, ethanol, 4-chlorobenzotrifluoride, and butyl glycolether. (Not toluene, acetic acid, or the mineral spirits, like that first one by Klean Strip.)

Was confused at the hardware store and it took all of that to figure out the difference there between these..

 

[bholler]

Sorry it'll be Laquer Thinner as a solvent to rinse residual grease, metal, ospho 'powder' and graphite [from electrolysis] prior to painting. Could skip and get away with it but this stuff is cheap. Mostly a hassle to use (toxic, fumes, flammable, solvent)

Lacquer Thinner - Klean Strip

kleanstrip.com

View attachment 337152
Most paint instructions for high heat stoves say mineral spirits leave residue - to only use laquer thinner for prepping to paint:

"How should I remove oil or other harder to remove contaminants?​

For oil, grease, graphite, or other hard to remove contaminants, use lacquer thinner, toluene, or acetone.​

Do not use paint thinner or mineral spirits as these products leave residue."​

Edit: That product above still has 1-5% Hydrotreated light distillate (petroleum, mineral spirits). So it does contain mineral spirits but the paint companies say laquer thinner is ok. If the bottle says 'Mineral Spirits" don't get that.

By the way, there are environmentally friendly laquer thinners containing *no* mineral spirits:

View attachment 337153
Some of the environmental ones contain acetic acid, some don't. The one above doesn't.
(You have to check the safety sheet documents online for the ingredients list).

Since the wire brush electrolysis got these clean, might just use the environmentally friendly version. That green envy one contains acetone, methanol, ethanol, 4-chlorobenzotrifluoride, and butyl glycolether. (Not toluene, acetic acid, or the mineral spirits, like that first one by Klean Strip.)

Was confused at the hardware store and it took all of that to figure out the difference there between these..

Ahh ok I see it says thinner in your first post but not the second. Definitely overkill with all of this but it will work as long as you follow with a high quality paint

 

[RobbieTimber]

Ahh ok I see it says thinner in your first post but not the second. Definitely overkill with all of this but it will work as long as you follow with a high quality paint

Will admit, wire brushing each foot for 30min with a drill was a lot as well, to get the paint off. well mostly because no vice

It sounds like other people dont have issues painting over old paint that much. If it was glossy, maybe. But yeah basically trying to avoid a 1% scenario of issue by going 1000%

dont know about how effective or consuming sandblasting is but that might be the bypass to much of this manual prepping

 

[begreen]

By the sound of it, I think I would just have it sandblasted.

 

[Rascus]

I agree with the sandblasting, that's been my go for these to get it done in one step. I actually sandblasted and used brass wire wheel on my own Reginald stove a couple years ago to restore it..

As an aside, this is bringing to mind a current project I am working on at my day job.. Laser cleaners are becoming more common and they take care of all this work in 1 step without damaging the surface underneath like electrolysis/sandblasting/wire wheels often will. You can go from rusted cast iron to paintable surface in minutes, without the need for wheels, media or large compressors. Maybe one day they will be more available for us weird folks that restore stoves

 

[stovelark]

My goodness, if I dedicated thought and time about the subject, I never would have gotten many stoves repaired/made presentable to resell, sell them. I thought I was more dedicated than most, cleaning the interiors a bit, trying to go that extra step to hopefully make someone think we went through them completely and trying to make them safe to use again, keeping someone warm. Glad you weren't one of my prospective buyers- LOL. I admire your dedication, but remember it is only a woodstove, a device to take care of surely, but its main purpose is to keep us warm. I still admire your effort... Stay warm.

 

[RobbieTimber]

Sandblasting and lasers may be a good high scale answer.
The electrolysis does not damage the surface material by its nature, which is one of its benefits.

The worst part is the wire brushing.
Got an angle grinder wire *wheel* but never used it.
That may damage the cast iron because they're tough (?)

The electrolysis part isn't too consuming - one can submerge some things and be wire wheeling / acid treating the other things.

The acid treating does seem to take some black carbon off in addition to any remaining rust.
With the goal of 100% bare cast iron, this seems to do the trick so far.

The process could be shortened but there'd be black paint leftover which I suppose isn't bad and primer can handle. Maybe if these weren't all rusty that could be a better route.

As you can see above there's some black left, even after acid treatment and scrub.
Have not rinsed this with laquer thinner yet , maybe that will dissolve it.
Either way it will be ready to paint as you all know.

Below is the ~9" stove pan acid treated (after electrolysis and wet wire scrubbing).
The acid is dry and ready for the final dry wire brush scrub.
Surprisingly good amount of material still taken off from acid step:

The main thing here was if this is being done may as well cover the bases and do it stepwise up to snuff, because it may end up taking longer to do without the proper tools, like the acid, or electrolysis part, which reduce labor input. After that the thought is ensuring the paint job goes well and is worth it - as much as possible, according to high heat stove paint instructions.

 

[bholler]

Sandblasting and lasers may be a good high scale answer.
The electrolysis does not damage the surface material by its nature, which is one of its benefits.
View attachment 337383

The worst part is the wire brushing.
Got an angle grinder wire *wheel* but never used it.
That may damage the cast iron because they're tough (?)

The electrolysis part isn't too consuming - one can submerge some things and be wire wheeling / acid treating the other things.

The acid treating does seem to take some black carbon off in addition to any remaining rust.
With the goal of 100% bare cast iron, this seems to do the trick so far.

The process could be shortened but there'd be black paint leftover which I suppose isn't bad and primer can handle. Maybe if these weren't all rusty that could be a better route.




View attachment 337381

View attachment 337378View attachment 337379
As you can see above there's some black left, even after acid treatment and scrub.
Have not rinsed this with laquer thinner yet , maybe that will dissolve it.
Either way it will be ready to paint as you all know.

View attachment 337380

Below is the ~9" stove pan acid treated (after electrolysis and wet wire scrubbing).
The acid is dry and ready for the final dry wire brush scrub.
Surprisingly good amount of material still taken off from acid step:
View attachment 337382

The main thing here was if this is being done may as well cover the bases and do it stepwise up to snuff, because it may end up taking longer to do without the proper tools, like the acid, or electrolysis part, which reduce labor input. After that the thought is ensuring the paint job goes well and is worth it - as much as possible, according to high heat stove paint instructions.

I'm sorry but I am usually done prepping a broken down stove in under an hour with a wire wheel on an angle grinder then wipe down. The only way it takes more time is if it was polished. Then you need chemicals or to sandblast because oil will be left behind with just a wire wheel

 

[RobbieTimber]

please do not apologize
this is fun
your comment is good to know

 

[RobbieTimber]

Good morning,

Some thoughts, to think and help others down the line as they decide..
To be clear, the primary [perhaps limiting] goal is removing 99.9% of debris, paint, and rust, before refurbishing.
If less time is desired, we up the 'leftover debris' meter and pay (not always but sometimes) with quality.

Assuming no access to sandblasting, and a goal of full prepping (no paint, rust, debris leftover):

The electrolysis and acid steps don't actually add much time.
Wire scrubbing is the most time intensive step, and this needs to be done anyways.
The electrolysis works when you sleep and makes rust easier to remove on a chemical and physical level.
Just need DC power supply & wire/sacrificial iron (rebar, sheet steel) or graphite sheets, washing soda.
Run at 10-15v, 5-10amps.

The question is do you want debris, rust, and paint leftover, or is it acceptable to paint over it a little.
Sure, we can paint over it but 1) we feel bad 2) it's not the proper procedure for professional paint jobs. It's just not.

Seems like a preference thing in the end, mostly bound by factors of time, not necessarily cost as the electrolysis and acid treatment steps are not too pricey.

Admittedly it sounds like you all get by ok with less intensive approaches that get the job done, but for those who can't sleep at night knowing they could have done the job to absolute full completion, this seems doable.

On the sandblasting do you think this $200 harbor freight setup straight from the shores of china would help? Or is this too weak?

(Scrubbing the feet was difficult because they were removed, as was the door and smaller parts prior to brushing. If the stove was upright and assembled and able to be wired down initially, intact, this would be faster).

 

[bholler]

Good morning,

Some thoughts, to think and help others down the line as they decide..
To be clear, the primary [perhaps limiting] goal is removing 99.9% of debris, paint, and rust, before refurbishing.
If less time is desired, we up the 'leftover debris' meter and pay (not always but sometimes) with quality.

Assuming no access to sandblasting, and a goal of full prepping (no paint, rust, debris leftover):

The electrolysis and acid steps don't actually add much time.
Wire scrubbing is the most time intensive step, and this needs to be done anyways.
The electrolysis works when you sleep and makes rust easier to remove on a chemical and physical level.
Just need DC power supply & wire/sacrificial iron (rebar, sheet steel) or graphite sheets, washing soda.
Run at 10-15v, 5-10amps.

The question is do you want debris, rust, and paint leftover, or is it acceptable to paint over it a little.
Sure, we can paint over it but 1) we feel bad 2) it's not the proper procedure for professional paint jobs. It's just not.

Seems like a preference thing in the end, mostly bound by factors of time, not necessarily cost as the electrolysis and acid treatment steps are not too pricey.

Admittedly it sounds like you all get by ok with less intensive approaches that get the job done, but for those who can't sleep at night knowing they could have done the job to absolute full completion, this seems doable.

On the sandblasting do you think this $200 harbor freight setup straight from the shores of china would help? Or is this too weak?

View attachment 337394

(Scrubbing the feet was difficult because they were removed, as was the door and smaller parts prior to brushing. If the stove was upright and assembled and able to be wired down initially, intact, this would be faster).

The blasting cabinet is just to small. If I need to blast something I typically take it to my neighbor who does powder coating and have him do it. Or if he is busy I just use his equipment. But a basic harbor freight unit works. As far as brushing goes a wire wheel on a bench grinder works great for small parts and you definitely need a vice. I find it's faster and easier to do a better job if the stove is broken down. But if it just needs a simple repaint I'm not doing that. It's also completely unnecessary to remove every trace of paint. If it won't come off with a wire wheel it's adhered well so I just feather the edge with sand paper wipe it down and paint. I use acetone or laquer thinner.

 

[RobbieTimber]

Thanks that helps on the sandblasting, sounds fun

Not having a vice setup or a grinder wheel did make this more difficult and this was all just holding pieces with a drill in hand under a bath tub spout. Like the Romans, with arthritis

 

[RobbieTimber]

This is the back plate without electrolysis after aggressively scrubbing with wire brushes.
Eeven soaking in laquer thinner to scrub once more.
The laquer thinner did not do much to the black stains, which are probably soot .

Currently there is 320 watts of pure power charging through in electrolysis as we speak,
nothing but bubbles. Lets see if we can get it 100% clean.

 

[stoveliker]

Soot doesn't adhere so strong that a wire brush can't take it off.
It is likely carbon that has diffused into the metal, discoloring it. It won't affect adhering of paint.

 

[RobbieTimber]

thanks ok

 

[begreen]

There's not a lot of reason for ultra-cleaning the interior of the firebox. That doesn't get painted. It's too hot in there for stove paint and it will get sooted and ashed up as soon as the stove is burning. If you want to prevent it from rusting over the summer, brush on some mineral oil on the inside after it's all assembled.

 

[Rascus]

Just for giggles, here is my old Regi. Came from my great grandfather's farm house. Dad remembers growing up with it in the house, dog curled up next to it all winter long. I'm guessing he cut the legs down to fit his chimney/configuration because I am pretty sure the legs were longer OEM.