If you like to tinker with old tools, sooner or later you’ll come into contact with a rusty example. I’ve been interested in methods that use lemon juice or vinegar to shift the problem. I like the fact there is no dry abrading and no electrical stuff, and the things you need to do it could not be more accessible.
I tried it out first of all on a early(ish) Stanley No. 4-1/2 I bought on eBay; you can see in the video below that it lived up to my expectations. And just a word on expectations: Don’t expect to dunk a tool in there and have a bright, shiny, perfect mirror of a tool come out the other side. Also think carefully about what you dunk; you could lessen the value of the tool.
After experimenting with the Stanley, I want to tidy up the plane iron and cap iron for the Matheison. Sadly, both are a little worse for wear; if I start introducing them in the current condition, the plane is going to look grubby fast. So here’s the before.
The cap iron was submerged in lemon juice and the plane iron in vinegar. I gave them 48 hours total in the bath, then inspected them. I was delighted with the results. I anticipated very similar outcomes as the pH of both fluids is quite similar. I used a pan scourer to rub them down and it was great to have have the filth suspended in fluid rather than have dry dust contaminating the area. I had it suggested to me afterward that I should of washed them in a baking soda fluid after scrubbing them, I would assume to neutralize the acid. However, I rubbed them down with my favorite honing oil (fragrance-free baby oil) and all seemed well. Here’s how they look after.
This is very much a method I would use in the future and I look forward to fitting them into the plane.
— Graham Haydon
Editor’s note: If you’re interested in rehabbing and tuning up a flea-market metal plane, check out Christopher Schwarz’s video “Super-Tune a Handplane.”