Singer 45K93 rust removal

[eddo]

 

 

Hi,  I'm a new member, and have acquired a cheap and neglected Singer 45K93 (circa 1964). The odd screw comes out after drowning in WD40 and a WD 40 penetrant,  so I believe it is still alive and metal intact, and with rescue. I love that it is still threaded. I have restored around 30 old domestic Singers (Covid obsession) but haven't yet encountered this much work.

I would like any advice on rust removal... prior to hopeful 'release' and a possible need to fully strip down-  but I'd like to get it 'moving' before deconstruction so I can learn more about its various actions first.  I am thinking at this stage after research that the best cheaper and safe? option (given that I need to submerge the whole thing to get to the inner rusted components) is to submerge the whole machine in a bath of oxalic acid.  I'd appreciate any advice!  i.e. will oxalic acid strip paint? (not that it matters too much). BTW Evapo Rust is very expensive here in Aus. 

Edited June 18, 2021 by eddo
moving image below text

[DonInReno]

I have a plastic tub that will hold an entire machine and have let machines set in vinegar (a mild acid) and also have also used the tub with electrolysis to remove rust.

Either method will remove rust, but there is a big difference between dry rust and oily rust - oil acts as a barrier and greatly increases or flat out prevents the rust from ever getting enough contact with the liquid to loosen the rust.   Take two rusty bolts - oil one up and leave one dry and try the rust removal process of your choice and it quickly becomes clear parts need to be degreased as much as possible.

Of the two methods I favor electrolysis because it’s possible to focus the flow of current through the specific part that’s frozen.  Either method will leave noticeable pits in the metal if used long enough.   There is no guarantee that the frozen up parts will come free before the rest of the machine begins to show objectionable pits.   It’s much harder to loosen up parts rusted together than it is to remove surface rust.

Either method is not a simple soak - it’s soaked a while, then all the loose rust should be wire brushed and then let it soak some more.    If you don’t periodically wire brush the rust,  there will be more pits in the less rusty spots before the thicker rust has been loosened.

I will stop when the surface rust is removed, but any frozen parts will still be frozen.  To finish freeing up parts I’m a big fan of a propane torch and brass hammer - heating and tapping over and over until there is movement.

I do know at least one guy who will let a rusty machine like yours set in the electrolysis tank until it’s free, but up close he must have a lot of pitting.   On the plus side he’s never had one that didn’t loosen up.

It looks like a great project!   Keep us up to date as you sort it out!

 

[Constabulary]

Electrolysis is the way I would go.

[eddo]

Thanks both for your speedy input. I'm currently working away from home... covid trapped in another state, so don't have access to many tools at all,  but I think I will try a mild acid bath and then electro zap the beast when I'm back home... in the meantime I've done a fair bit of wire brushing and found plenty of fine steel underneath. BUT...  Some tapping to release components and I've learnt my first major lesson... checking what the next link is in the sequence... In tapping a lower link arm in the main body of the machine, I've stressed and cracked another linking piece at the top of the associated rod. Watch this space... I'll find the part number and start my hunt... I'll attach an image of the good, and the bad, below. Let me know if you know this link arm part-  it looks replaceable- with two accessible bolts... but its a matter of wether I can locate the part. Now I'm going to slow down...

 

Edited June 19, 2021 by eddo
clearer image included

[eddo]

Please note I've now created separate post relating to this cracked component.

[dikman]

Yes, Evapo-rust is expensive here in Oz (prohibitively so, in my opinion) but there is a similar product sold by Repco at about half the price. Given how solid some of that rust looks electrolysis and wire brushing is probably the best way to start. Don's suggestion about vinegar is also a good one.

[eddo]

Great thanks-  I have it soaking in oxalic acid at the moment- couldn't find enough bulk vinegar near where I am so went for another mild solution- its quite a hefty machine so I needed the full 2kg to immerse,  with a few bricks, then I'll roll it over tomorrow. The Repco product I will check out in the future...   I have in mind you did a restoration once on a 45k am I right? Let me know if you can offer any advice on the part I've cracked (see earlier post), or any general 'releasing suggestions (apart from telling me to take more care..!). Cheers. 

[jimi]

Hi Eddo, Nice find and good to see you are saving old rust! The part broken will be on the 45k89 machine (45k56 and 89) here on the net.https://www.hendersonsewing.com/manual.asp?page=72 Looks like part #3033, the Feed Connecting Link, so like you say you will have to find a machine with reverse for parts and with the 45s they were not all that common with the reverse feature. Maybe you could try and repair it meantime by Tig welding? or brazing? That is the risk with old machines, some of the screws are really tight and can pop!. I normally apply WD40 then after that lots of oil, if it wont move after a slight tap with a hammer (if possible) then i get a small blow torch out and that usually frees it up. It doesn´t normally need a lot of heat to move them but if it is a no no then i tend to leave it where it is. It´s a pity because 1964 was near the end of the 45k run and it should be in very good condition normally but that one looks like it was lost in the bush!!  I am sure it will work and look great in the end. Keep on truckin!!

Just had a look and looks like Cowboybob is right, the connecting link looks the same as on my 21 but it has another part nº?? # 52165??

Edited June 19, 2021 by jimi

[eddo]

Thank you Jimi... this is all helpful once again. I now for some people this one might be a bin job- but this is where my machine interest started-  I'm attracted to the rescue, but this is not a two hour free-up like I've had in the past. Its a shame it was left exposed to the elements, as it is so intact- which probably means the mechanics are good beneath the rust.

I'll douse it with WD40 then  oil once it is out of the bath tomorrow, then  try some heat this week... it seems well bound up- I need to observe some vids of moving parts to know exactly which bits should move and how far- this is a new machine to me. My son is a fitter, so I should be able to get that part machined if I can't fix it any other way or find a replacement.

[DonInReno]

Ouch!   That’s a bummer, but you’re not alone - many of us have had that sinking feeling in the gut from breaking a cast iron part and that’s just part of the learning curve.   Old machines can be very hard to get parts for so I’d almost plan on having the broken part repaired - in this case it won’t be a difficult/expensive repair.

 

[eddo]

Bummer indeed... just too keen to get movement.  As long as I can get the part off... there are two bolts, and I notice, from what I can see, one at least has a screw slot on its other end (behind that main link arm to the left in the image above. It also seems like I'll have to get it moving to access both bolts which poses a problem given the weakness I've generated

[eddo]

Guys,  I've also found that same link arm part 52165 supposedly on a 95-1... and I have one of these at home for scrapping so might be in luck- just not there for a couple of weeks so will hang in suspense.  Thanks again for leading me in the right direction.

[jimi]

https://youtu.be/I0xx53jufMI see if you can open this eddo....

[jimi]

Yes the 95-1and 95-2 has the same part number #3033 same as the 45k89

[eddo]

yep.. my son has confirmed that the part is there inside the old 95k1... and has also asked when it will be moved from his shed! 

I couldn't open that vid Jimi...?   below are some progress shots. First, the machine out of the oxalic acid bath after 15 hours.. comes out a bit greyish and dulled but major rust gone, paint fine. Then penetrant, wd40 dousing and lots of oil.. Still seized but I've got 1mm of play in the flywheel, so I'm rocking that back and forth every so often..I'll try to coax the needle plate screws off with some heat applied to the plate, and do some gentle tapping... When I get it back home in a couple of weeks I'll probably go the diesel bath route if it is not moving by then. I can't even get the presser foot bar to shift yet. My $100 investment is sure providing me some entertainment at least. 

 

[dikman]

It's looking a lot better than it was! Localised heat/pin-point heat is a good method for loosening stuck screws, along with tapping the screwdriver. A good home-made penetrating oil is auto trans fluid and acetone, mixed 50:50. Sounds like you've got a pretty good idea of what you're doing, I look forward to some progress reports.

[eddo]

OK... so I've now shipped my 45K93 back home to my familiar world of tools, and as it is still well seized after the initial acid bath de-rusting, a couple of weeks of oil, wd40, off the shelf penetrants.. I can only guess theres still some gunk between joints that is not allowing enough movement despite hefty weight, levering and tapping applied the the flywheel. I've been doing a bit of heating, cranking of parts that i can get to (Jimi's vid was useful see what actually moves, thanks...), but I just can't free it up yet.  I've decided that given its shoddy state and the fact that I want a 'user' rather than a seller,  I'm going to give it a lengthy electrolysis bath and see how that goes- even if it eats a bit of metal..  I would appreciate some advice about how to go about this-  I know the basics, and have a low voltage car battery charger, just not sure what to hook up to for best results, given the machine will be complete when it goes in.  Any tips at all welcome.. i.e. what do I best add to the tub to attract the rust, steps on process, timing etc..

 

[Constabulary]

Often the main problem is a seized needle bar. I would loosen the the 2 clamping screws on the NB clamp and apply heat (maybe with gas blowtorch) on the bushings and oil them and try to free the NB with a piece of wood and gentle hammer strikes. Heat and oil will most likely loosen the top shaft too if it is seized.

this was my ".45" project - pretty much the same machine :

 

Edited July 3, 2021 by Constabulary

[DonInReno]

It’s always a good idea to start experimenting with electrolysis by treating old rusty tools and bolts to get a feel for what works and what doesn’t.    If not done carefully you can ruin the entire machine - there is a good amount of misinformation online saying only rust is removed and it doesn’t damage the metal.   Electrolysis is removing metal - the trick is to only remove as little as possible.    Many instructions online over simplify the process and just say hook it up and leave overnight.  The size of power supply and concentration of electrolyte in the water change the speed at which metal is removed by a factor of 10x or 20x.

The chemical process is straightforward - metal is eroded from the negatively charged side and deposited on the positive.    The machine is hooked to the negative and a scrap of metal is hooked to the positive.    Water has to have an electrolyte  of some sort for the electrons to pass - salt, baking soda, lye and any number of substances will work, but washing soda (sodium carbonate) is typically listed as ideal for this purpose.   Lye has the additional benefit of removing paint and degreasing - if chemical burns or worse life altering injuries can be avoided.  In a 5 gallon bucket I just add a roughly measured cup of washing soda.   

The smaller the power supply the slower the process will be - I have a small 12v car charger for longer overnight soaks and a small 115v arc welder that works quickly at 28v and many times the amperage.  

The bubbles given off in the process are flammable so do this outside.

For me, the key to getting the best results is in the size and placement of the positive electrode as well as the negative electrical connection to the machine.    Electricity follows the path of least resistance - if a shaft is frozen and the connection is made to the machines base and the positive electrode is nowhere near the shaft then nothing helpful will happen.   Much better to energize the shaft on one side of the rust and place the positive electrode near the other side of the rust.   This is something you need to develop a feel for by experimenting on other items before using it on your machine.

Rusted/frozen areas need to be degreased prior to soaking - oil is a barrier to the electrolyte.    All the penetrating oil that has been applied should be flushed out as much as possible.   Avoid break cleaner because it can remove paint.   A soak in dish washer detergent and hot water works well to degrease, but will dull the paint somewhat.

Periodically the item has to be taken out and wire brushed to judge progress - it’s unreasonable to expect this to be a simple matter of soaking until it’s all rust free.   It’s aways fun to learn a new tool to use with old machines, but as with many things, this is easy to do, but difficult to do well without practice.

Screws and shafts will still need to be removed with heat - there’s no way around getting a propane torch and developing a feel for how much heat and where to put it.   Honestly, if you really like the machine you’re working on, find a low value rusted up machine to practice on.   As with anything new, it’s always a good idea to not practice on the machine you’re trying to save.

As much as possible try not to put pressure to move one part by putting more than normal pressure on a different part.   For instance if the needle bar is stuck, don’t crank hard on the handwheel to free it up, but rather find a safe way to tap on it directly with a wood, brass or aluminum block of some kind.    

Keep up the good work - we look forward to seeing it sewing again!

 

 

 

[dikman]

A very nice summary of electrolysis, Don.

If you use salt for the electrolyte it generates hydrogen (just so you know). If you run copper wire to various parts of the machine and common them to the negative electrode it may spread the electrolysis effect more evenly around the machine but as Don said it's important to make sure you've got a good clean metal-to-metal contact. A lower voltage may take longer but it will be more gentle, even 12v is considered high by some. For the positive electrode any scrap steel will be fine and using several pieces around the edge of the tub, commoned together, will help given that this is a complex shape to clean.

For something like this the Evaporust-type cleaner would be ideal, as it will not harm any of the metal, only the rust, but unfortunately the quantity required would make it very expensive here in Oz (even the Repco one, at half the price, would likely be a couple hundred $$).

I suppose you could always use a sand-blast cabinet if it's that bad! (Just joking).

Edited July 3, 2021 by dikman

[eddo]

Great thanks - the link to your 2016 restoration was inspirational to say the least.. good to know a place to start to free up-  hard to know when nothing moves. I'll see if I can get some movement around the needle bar, and give it an electro bath to release the last bits of rust.