78-1 Singer Model 78-1. Bought frozen to get sewing.

[DonInReno]

10 hours ago, Quade said:

One of the things I liked about "Evaporust" is it seem to have no impact on non-rusty metal.

I should try evaporust again - maybe the pits were already there and I misjudged what was going on.

Once upon a time there was a guy who enjoyed buying rusted and locked up old Singers at auctions - he liked electrolysis and said hooking up the wire on the shaft that was frozen would get any rusted shaft to turn.

[Quade]

I'm always leery of running electricity through bearings. Either with welding or other processes.  I just worry there will be some arcing that pits the races.   

What locks up on these machines? I imagine most have a ball bearing near the hand wheel and lower belt gear.  Is it the bushings that freeze up on the shafts? 

[AlamoJoe2002]

The bottom rod running from pulley to the head works was stuck. Also the three vertical foot and needle shafts were stuck. With a pint of mineral oil, time and working the movement back and forth, it eventually started moving. I need a new leather treadle belt...then I will give it motorized power. Not sure what follows.

[rlevine]

Another vote for Evaporust. 

A few caveats when using it:

• There may be some etching or metal removal, contrary to expectations that part size isn't changed. That expectation is almost always met, but realize that if the part is rusted, the oxidation is consuming the metal of the part surface. Chelating the oxide and removing it takes something away. In most situations you won't be able to tell or it won't matter, as tolerances in most parts will still be within a useful range. (And yes, Virginia, Evaporust is a chelating solution. Molasses has a chelating effect but it's sloooow. Chelating agents will _stop_ when the oxide is converted. Acids and electrolysis will remove unoxidized metal and don't stop. Electrolysis can deal with severe rust that's too much for Evaporust, but takes time to set up and needs to be watched, so the result should be worth the time.)
• Always submerge parts completely, if you're leaving a part in Evaporust for any amount of time. There can be a visible line left on a part at the liquid/air boundary. I've seen both black chelated residue at the line, with none above, or actual etching on some metals. Both can be a pain to recover from. 
• Evaporust will usually leave painted surfaces alone, unless the finish can absorb it or there is oxidation under the paint at the edges. Test it first. Japanned finishes may not like it. 
• Don't leave parts in the juice for more than an hour or two without checking on them. They'll probably be fine, but I'll miss submerging a part fully, or there will be some galvanized stuff that I missed, so rescuing them sooner rather than later is always nice.
• The temptation is to take the parts from the Evaporust container and drop them into water to clean them off. Don't; they'll turn black. Clean them one by one. (Returning the parts to the Evaporust will remove most of the black, at least enough to make you think you ducked a bullet.)
• Don't throw away the used solution. The counter to the complaints about price are that the stuff can last for years if decanted back into its bottle or kept in a sealed tub.

I'll throw in some of the techniques I use when working on machines, since I couldn't find much advice in one place when I started trying to resurrect rusty things. (And yes, these are only my opinions, and what I've found that works for me. YMMV.)

• I keep some 600-grit wet/dray paper handy when using Evaporust; having a sheet flat on a surface using Evaporust as a lubricant can quickly clean up flat surfaces on parts, and small pieces of paper can be used for cleaning up non-flat bits. A few pieces end up in the tub, and I'll just grab one as I pull parts out.
• Ace hardware sells small brass wire brushes in 3-packs. I'll pretty much kill one for a machine restoration.
• Small screwdrivers and probes and a stack of micro-fiber cloths are my go-to's for cleaning parts. I have a particular liking for Wiha's 3.5mm flat screwdrivers, so there are lots of them scattered around machines in the shop, and I usually end up using one to clean and remove parts. (Yes, I'm disrespecting the tools. But they work.)
• For general degreasing and cleaning, since I don't like working with kerosine, I use Rustoleum's Krud Kutter, either straight from the spray bottle, or cut 50/50 with water in a tub. Again, brass wire brushes or a small bristle brush. Krud Kutter will affect some painted or japanned finishes. Test it, don't let the concentrate sit on paint.
• Rustoleum's rust converter is great for a wipe-down to remove flash rust on parts, but it's vicious, poisonous stuff that doesn't stop working until it's rinsed.
• The better alternative I've found is to pull a part from the Evaporust, clean it up, wipe it down if it's small or rinse in warm water and wipe, and then put it in a tray with a piece of paper towel in the bottom and hit the parts with a quick shot of LPS1 lubricant to displace any water and keep them shiny until I get back to them.
• Johnson's paste wax is a decent treatment for exposed metal surfaces that need to be slippy for fabric or other processes that don't like oil or grease. Never, never, never use microcrystalline wax, as it can't be removed without serious abrasion or hot xylene, which you don't want to deal with.
• Get some good screwdrivers, or grind your cheap ones to improve them. A Chapman set is a great start, or look for electrician's tools; for some reason they're often hollow ground.

Again, only my $0.02, but I wish had some cogent advice about this stuff when I started taking machines apart. 

Edited April 14, 2023 by rlevine

[DonInReno]

On 4/12/2023 at 6:48 AM, Quade said:

What locks up on these machines? I imagine most have a ball bearing near the hand wheel and lower belt gear.  Is it the bushings that freeze up on the shafts?

These are pretty simple machines, but the needle and presser bars are somewhat exposed along with bushing nearest the hook.

Luckily many sewing machines that are locked are only suffering from old oil that has hardened throughout and eventually softens up with a little solvent or even new oil.

Rusted machines on the other hand suffer the most in the areas water can get to.   One of my projects sat outside for a few months before it was sold and the bushings with direct paths for liquid water are the most corroded, while others exposed to high humidity and no liquid water get rusty all over and under.  

[shaggyrun]

Alamo joe, did you get your 78-1 running? I was gifted my grandmother's old upholestry machine turns out it is a 78-1 that was made in 1920 in new jersey. After 2 days I was able to get the machine turning over again.  It had been stored in a barn for about 50 years. I used kroil and it really helped getting things going.  My bottom bobbin shaft was the biggest problem. I was able to flip the machine on is side spray the bottom shaft down really good with kroil and then use vice grips to clamp on the shaft and slowly work it back abd forth not putting to much pressure on anything. After a few minutes it break loose and freed up.  

I don't know if that will help you but I have mine working and it's truly a beast and the stitch quality is better then my newer machine.