Got My First Lathe... Logan 1875 - With Restoration.

Doesn't seem to damage machined surfaces but you could tape over the ways and then spray it on. You do not need to use this but I do it for most stuff I treat with ERR and it works for me.
 
+1 what Mikey said about Ospho (phosphoric acid) as part of your metal prep.

Ospho is a brand name I think. Sold in local hardware stores. I've used it around boats for 45 years and keep a gal jug sitting on my welding/grinding bench. I routinely use it to get rid of rust on old steel, and to clean up weldments before machining or painting. I usually apply it with a cheap throw away chip brush, then let it air dry overnight.

Phosphoric acid chemically changes iron oxide AKA 'Rust' to iron phospate, but is non reactive with the underlying steel and/ or iron . The iron phosphate acts a moisture barrier, preventing rust. You do need to wire brush the extra grey or black colored residue off the work before overcoating - not all of it. Just the loose powdery extra stuff.

As a side note, If you want a really good prime coat, you might consider using marine undercoater, such as Interlux Pre-kote (I think it is a one part polyurethane) or their one part epoxy Primecoat. This stuff adheres exceptionally well to metal surfaces. like fleas on a dog, as they say. Forms a second superb water tight barrier against rust formation.

As Mikey said, tape off your ways and other machined surfaces, before applying.

Glenn
 
Hey Laytonnz..
I was thinking of adding a hardener to the oil based paint but I've never shot Oil ( well except Rattle Cans of Rust-oleum ) only Water based products. So I'm real worried about using my Compressor Hvlp Gun to spray it, Actually I'm thinking about buying the hand held Graco TrueCoat 360 airless.. because I don't have an air Desiccant filter for my Hvlp to stop moisture. and my regular airless Is a full size so it takes a Qrt just to fill the hose.. What do you recommend..?
Just use a disposable moisture trap, I use one on my gun.. they are only a few $ each.

But do wear a good respirator.

An airless sprayer will put far too much on, well our big Gracos do.. I only use a 200ml touch up gun for painting machines perfect for geting in small spaces and around all the handles ect without putting too much paint on

Sent from my GT-I9505 using Tapatalk
 
+1 what Mikey said about Ospho (phosphoric acid) as part of your metal prep.

Ospho is a brand name I think. Sold in local hardware stores. I've used it around boats for 45 years and keep a gal jug sitting on my welding/grinding bench. I routinely use it to get rid of rust on old steel, and to clean up weldments before machining or painting. I usually apply it with a cheap throw away chip brush, then let it air dry overnight.

Phosphoric acid chemically changes iron oxide AKA 'Rust' to iron phospate, but is non reactive with the underlying steel and/ or iron . The iron phosphate acts a moisture barrier, preventing rust. You do need to wire brush the extra grey or black colored residue off the work before overcoating - not all of it. Just the loose powdery extra stuff.

As a side note, If you want a really good prime coat, you might consider using marine undercoater, such as Interlux Pre-kote (I think it is a one part polyurethane) or their one part epoxy Primecoat. This stuff adheres exceptionally well to metal surfaces. like fleas on a dog, as they say. Forms a second superb water tight barrier against rust formation.

As Mikey said, tape off your ways and other machined surfaces, before applying.

Glenn
Hi Glen..

Is that acid mix still necessary for removing oil from parts after doing 18+hrs of electrolysis..? My understanding is the electrolysis does that already.

Or is it to just keep parts from flash rusting..?

Thanks Mike.
 
Mike,

Yep, mostly to prevent further rust formation. In this case it becomes the first primer coat - stabilizing the freshly cleaned surface by sealing against moisture formation .- thus preventing oxidation. (Sometimes I do this just to preserve the steel for long term storage.)

It can also be used in lieu of electrolysis, but usually only after removing heavy rust and scale with some sort of manual surface grinding with a wheel and wire brush. The acid can only chemically react with the wetted surface, so sometimes doesn't penetrate deep enuf into a rusted surface to get rid of all the iron oxide.

As an aside, I have found it can act as a cleaner as well- cutting all sorts of grime and some oils, (but not all) from a variety of materials and surfaces - and its great for dissolving/cleaning welding by products. But I haven't found it particularily effective on fresh machine oils.

when I restored my old Dalton Lathe and Burke #4 horizontal mill, I stripped down the castings much as you have done. Then scrubbed and cleaned the bare metals with: 1) diesel, then 2) paint thinner, then 3) Ospho. Cleaning the residue each time. Then applied two coats of Interlux marine undercoat and two coats of finish. The thinner removes any left over diesel and diesel smears, and cuts the oils and trace debris that the diesel didn't remove. Vice versa, the diesel removes some rust and cuts the dried oils that the paint thinner doesn't work on.

BTW, a little trick - if you have a delay of a few days in prepping your raw castings, spray with WD 40, or slop on some clean diesel with a brush. this protects the bare metal surface against oxidation while you are maybe treating other parts. Then when you have a batch of components ready to paint, clean everything well with thinner and go right to your metal etching undercoat.

There's lots of ways to do all of this...

glenn
 
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Mike,

Yep, mostly to prevent further rust formation. In this case it becomes the first primer coat - stabilizing the freshly cleaned surface by sealing against moisture formation .- thus preventing oxidation. (Sometimes I do this just to preserve the steel for long term storage.)

It can also be used in lieu of electrolysis, but usually only after removing heavy rust and scale with some sort of manual surface grinding with a wheel and wire brush. The acid can only chemically react with the wetted surface, so sometimes doesn't penetrate deep enuf into a rusted surface to get rid of all the iron oxide.

As an aside, I have found it can act as a cleaner as well- cutting all sorts of grime and some oils, (but not all) from a variety of materials and surfaces - and its great for dissolving/cleaning welding by products. But I haven't found it particularily effective on fresh machine oils.

when I restored my old Dalton Lathe and Burke #4 horizontal mill, I stripped down the castings much as you have done. Then scrubbed and cleaned the bare metals with: 1) diesel, then 2) paint thinner, then 3) Ospho. Cleaning the residue each time. Then applied two coats of Interlux marine undercoat and two coats of finish. The thinner removes any left over diesel and diesel smears, and cuts the oils and trace debris that the diesel didn't remove. Vice versa, the diesel removes some rust and cuts the dried oils that the paint thinner doesn't work on.

BTW, a little trick - if you have a delay of a few days in prepping your raw castings, spray with WD 40, or slop on some clean diesel with a brush. this protects the bare metal surface against oxidation while you are maybe treating other parts. Then when you have a batch of components ready to paint, clean everything well with thinner and go right to your metal etching undercoat.

There's lots of ways to do all of this...

glenn

Hello Glen..

Thanks for the Information.. Its always good to have extra tricks up ones sleeve.

I think that for my situation and geographical location stopping " Flash Rust " would be the most beneficial to me, once the part has dried it would take a good year for clean covered bare metal parts to show any signs of rust here Las Vegas, On average we have 20 days rain - about 4 inches a year..

I work under a roofed but open air porch attached to the house, I would be concerned spraying acid in the patio area, but if it has no effect on vegetation I could do it middle of the back yard..?

Good day Sir.
 
Got a spray kit with a detail sprayer from Harbor freight " It holds 4 ouncs "- It's orifice is only 1.0, I also picked up a Dryer/Filter for it.
Ill do some testing and practice on some scrap with the oil based paint and report back the results. lol had warnings stickers all over saying to clean gun if idle more then 5 minutes, between coats and/or refilling the paint cup, lol it used to say 20 minutes on other's I have bought - Item 60239.

SmallSprayGun.jpg
SmallSprayGun2.jpg
 
had warnings stickers all over saying to clean gun if idle more then 5 minutes, between coats and/or refilling the paint cup, lol it used to say 20 minutes on other's I have bought
5 minutes would be long enough if spraying lacquer with a hot thinner. Oil based, 20 minutes is fine. A clogged nozzle is a PITA.
 
Next time you talk to your buddy at the paint store, ask him what he thinks of spraying on a 50:50 mix of Phosphoric Acid and water onto metal that has just come out of an electrolytic bath. Stops all flash rust, etches the metal and can be painted over. Been using it for years and never had an issue with paint lifting and such but he's the paint expert and I would defer to him.

I stopped back at PPG and got my paint & supplies, while there I asked about the 50/50 Phosphoric Acid & water trick... Same guy I talked to before, He said he's not heard of that trick.

I think I'm going to give this a shot too thou, I have allot of parts left to do electrolysis on, when I say allot, I mean the whole lathe still - minus the bed.. so I have plenty of time to put the trick to use..
Please give me the safety of use run down... I'm guessing use a small spray bottle, Gloves, Eye protection and spray away from your self over an area where runoff will have little or no effect like a lawn.

Thanks Mike.
 
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5 minutes would be long enough if spraying lacquer with a hot thinner. Oil based, 20 minutes is fine. A clogged nozzle is a PITA.

Hi Bob.. Ill be spraying Oil without additional hardeners hopefully today, so 20 minutes sounds sooo much better :) Wish me Luck..
 
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