DIY Safe Rust Removal

I've got to share this.  A couple weeks ago I saw on YouTube a video by a gun restorer who had developed his own homemade version of Evaporust.  The video is fantastic and I highly recommend it to anyone who needs to remove rust from old tools (or other items).  He gives a formula which depends on what ingredients you use, but for me this was:

Citric acid (powder) - 100 g

Baking soda - 63 g

Water - 1 liter

Dish soap - about a spoonful

I had to try this out and it worked fantastically well.  Into the water, put the baking soda and mix until dissolved.  Then add the citric acid.  This will cause an immediate reaction with the baking soda, so add this slowly and use a container that has a wide opening.  I used a tray about 18" long, 6" wide and 2" tall.  After the reaction has completed, add some dish soap.  This reduces surface tension of the liquid and helps the solution "wet" the metal pieces that are placed in it for rust removal.

I've placed some things in it for a few hours and also for about 24 hours.  I didn't see any removal of base metal - the maker marks on auger bits were not damaged at all.  But I did get great results with the rust - both after a few hours and after a day.  It leaves an "oily", dirty residue that cleans off with a rag and then I used a brass brush to really get things looking nice.

Check out these two pics of a few auger bits.

Bits as found

Bits after the rust bath and cleanup with a brass brush

Here's the maker's mark on the largest of those three bits.  It's from The James Swan Co.

Honest - there really is a name on there

Now you see it

I've de-rusted several auger bits, a couple chisels and some other bits and bobs, and the solution is performing very well.  The only extra thing I had to buy was a kitchen scale to weigh out the ingredients.

I'm really chuffed about this and felt I had to spread the word.  I've never used Evaporust, so I can't compare the two.  I've used citric acid by itself, but didn't get results quite like this.  I've wanted to find something safe that can be made at home and disposed of without worrying about environmental consequences.  This fits the bill.  I'd love to get comments about this.  Have any of you had similar results?