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.