Clausing 8530 Restoration

[pontiac428]

Kleen Strip concrete prep is 50/50 HCl/PO4, and it is advertized as a metal prep for painting. I like it because it is cheap and takes off rust, too.

OSPHO Rust is 50/50 chromic/phosphoric, costs $40/gallon at the hardware store, and works well diluted. When I dilute OSHPO, I use hot water from the tap, and drop parts into the warm solution in a bucket. The prep does blacken, as phosphoric acid does, but that grey/black finish it leaves takes a bluing better than bare metal. Cerakote and K&G both recommend phosphate pre-treatment before painting, too. I also like that phosphate-blackened parts, once rinsed and dried, don't flash rust and are stable for a long time, and still take buing.

Nitric acid is usually the first one you would go to if dissolving metals is your goal. Nitric doesn't blacken, but the nitrate gives over to bluing very easily compared to hydrochloric (talk to my buddies Boltzmann and Gibbs about how that works). Nitric acid is no more or less a hazard than HCl. It's more of a hazard than glacial acetic if you dump it on your skin, but less of a hazard than sulfuric, which can be bought at the auto supply store and concentrated on a hot plate. No, nitric acid has always been difficult in the US. I can still buy it at the hardware store in Germany, right next to the nitro solvent, but the reason you can't buy either product here here is simple- the gubmint is protecting you from terrorists. What they don't know is how easy the salt acids are to make from common things. It's easier than moonshine, so that bar is low.

 

[ElginAgain]

Thank you for the explanation! I'll give the Kleen Strip Concrete & Metal Prep a shot as pretreatment, since I've got some laying around.

Do you think Ospho is better for this application, since it doesn't contain HCI? I read your response a few times and couldn't decern if you just like the Kleen Strip for general rust/paint prep or specifically for bluing?

I think you're on to something here. Some of the best looking pieces, the large cyclinder and the leadscrew nut retainer, didn't get the HCI treatment and instead went from evaporust to a deburring/finishing wheel and into the hot caustic.

Man, I wish I'd paid more attention in Chemistry class. I'm over here googling phosphate vs phosphoric, nitrate vs nitric, I have limited understanding of these things but I suppose that's where being autodidactic comes in handy.

It's good you mentioned Cerakote prep. I've also read about phosphate treatment for powdercoating, both of which are processes I do somewhat regularly. I may try incorporating phosphate pretreatment into those as well now that I'm making the connection in my brain.

 

[pontiac428]

I cold blued a bunch of stuff this year using combinations of prep trying to find efficiency (best outcome for minimal prep). All of the stuff that I soaked in Kleen Strip came out nice. I think the Ospho is the winner, though. It's easier to clean and has no HCl.

Sorry for the shorthand, PO4 is phosphoric acid, and when I say nitrate I'm referring to the anion in nitric acid. What I said about Gibbs and Boltzmann has to do with the order of preference for the chemical reaction, really inferring that iron phosphate is a better base prep for bluing than chloride for conversion.

The tool holders on the right were soaked and scrubbed in Kleen Strip concrete prep. The white oxides are from the HCl, and as they absorb moisture from the air, they form a little rust. Caustic or acid bluing solution removes the oxide, as does a wire or deburring wheel, and they blue nice. Ospho treated parts only get trace amounts of oxide, and can be blued directly if you're not going for a polished finish. The Ospho parts also don't rust at all, they stay dark grey for a long time.

 

[Nesse1]

Kleen-Strip Concrete & Metal Prep is phosphoric acid. I use that stuff to derust and prep before painting, and it's amazing. Home Depot sells it for $18/gallon, and you can reuse it again and again. It can be diluted also, and it's nicely effective, just a little slower.

Klean-Strip 1 Gal. Concrete Etch, Metal Prep and Rust Inhibitor GKPA30220 - The Home Depot

For Pro's and DIY'ers, Klean-Strip is the leading brand of solvents, thinners, removers, and cleaners that are dependable for reliable results. Klean-Strip Concrete and Metal Prep does the job of three

www.homedepot.com

 

[pontiac428]

You gotta watch these petrochemical companies, they pull the ol' switcheroo on you all the time!

As one of those additional duty things, I review and approve chemicals for health for the O&M side of an organization that employs nearly 25,000 people locally. I read many SDS per day with my coffee, and since I'm me, I tend to remember certain line items and the products they go with. That's background, the point is not 6 months ago Kleen Strip concrete etch was listed as equivalent to 50/50 phosphoric and hydrochloric acids.

This SDS (below) came out several weeks ago, now it's all phosphoric. That is actually fantastic for those of us using it on metal, the concrete prep users are (maybe) taking the hit for the change. Then again, crystalline citric acid is just as good at concrete, it's cheap, safer and a bit slower. Maybe Kleen Strip wanted to enhance the metal prep aspect. I'm cool with that, and you can't beat the price. I still think evaporust is the cleanest and the chromic acid in Ospho makes it top shelf for toughening the oxide layer. From a health risk perspective, using chromic acid is an issue. It's pretty spooky stuff in the long term.

 

[Nesse1]

You gotta watch these petrochemical companies, they pull the ol' switcheroo on you all the time!

No kidding! I love Kleen-Strip, but they do change their products regularly, so you gotta watch.

I'm using some stuff they label Metal Prep, which is phosphoric acid. This newest formula seems identical, only they call it Concrete & Metal Prep. It's hard to know what you are buying these days...

 

[ElginAgain]

The white oxides are from the HCl, and as they absorb moisture from the air, they form a little rust.

I have noticed when using Kleen Strip in the past, that if left to dry on the metal, it produces white chalky residue. Only did that once before I started rinsing it off the parts before it dried.

 

[ElginAgain]

The table transverse handle and leadscrew assembly are all nicely finished up. Amazon supplied me some cheap (Qty-10 for $13.42) PGN 6201-2RS bearings to use on all the lead screws. I figure these bearings don't need to be anything fancy since they're not spinning very fast. Hopefully that's a safe assumption.




Next up was the cross slide.
Here's the before shot.


Take a close look to see if you can spot my assembly error...




I got some close up shots of the lead screw nuts to show off how clean I got them. They were packed full of grease from the previous owner.


It was around this time that I went searching for the wiper retainers so I could install my fancy new felt wipers from farmboysales.com. I couldn't find them and it suddenly dawned on me that the retainers for the knee wipers were made of aluminum. I seem to remember pulling a load of parts out of the caustic hot tank and thinking it was a bit lighter than what went in. I'm certain that the aluminum wiper retainers just dissolved into the bottom of the tank never to be seen again. So I called Clausing asked for replacements and ended up with a drawing since they're no longer in production. Using that drawing as a reference I drew my own version of it up in Autodesk's Fusion 360. I thought then that I'd print the drawing and use it as a template to fab up an aluminum replacement.



Got the part all fab'd up but something wasn't quite right...


Guess it's never too late to check the drawing for scale. Doh! So close but not quite there.


Feeling defeated I turned to the 3D printer. The 3D printed ones fit perfectly.

 

[ElginAgain]

Next up was the table. It was a greasy spray painted mess before hot tanking.



After hot tanking it was just rusty.


After electrolysis, rinsed and blown dry.


I then doused it in WD-40 and scrubbed with gray Scotchbright. I hit some of the dings in the top lightly with a stone, but I didn't want to get too carried away.

I didn't get many photos of it at this point but I did get a few as evidence of the wear in the ways. You can see even in the center where the wear is most likely to occur, it's only just begun to wear through the original milling marks.




Before installation I hit all the surfaces with a liberal coating of way oil, spread around with a disposable paint brush. Then I slid it into place.



Oh also, the machine has found it's home in the shop. Never mind it's new neighbor, Logan, that's my next project.

 

[pontiac428]

I've been really impressed at how you went about your upscaled e-derusting setup, and now it is really paying off for you. Fantastic work!