|Chris Bill||03/03/2022 19:47:46|
|15 forum posts|
Looking to purchase some blueing solution (gun blue) to start preserving some of the steel I've been turning. Does anyone recommend a particular brand?
|Bill Phinn||03/03/2022 20:08:39|
|755 forum posts|
I have used Bisley Gun Blue.
If rust is what you're aiming to preserve against, I don't regard this, or any of the other bluing agents commonly available, as having serious preservative properties.
|Chris Bill||03/03/2022 20:25:47|
|15 forum posts||
I guess substitute 'make it look nice'. I'd heard that gun blue helps create a surface that better retains oil thereby fighting corrosion when properly cared for but I'm newer to this hobby than pretty much anyone else here, so open to suggestions.
|Mark Rand||03/03/2022 20:48:41|
|1275 forum posts|
The simplest solution is hot oil bluing. Heat the parts to hardening temperatuse and then quench in old motor oil. Temper to suit.
I've still got a tap wrench that I made in apprentice training school that looks good (and works) after 45 years.
Edited By Mark Rand on 03/03/2022 20:49:53
|duncan webster||03/03/2022 22:07:13|
|3990 forum posts|
I have a recipe using Sodium Nitrate, Sodium Nitrite and caustic soda. Given to me by a chap in the toolroom where I worked nearly 50 years ago. As you have to boil the components in this witches brew it sounds like a recipe for disaster, but if anyone wants it I'll look it out
|Mick B1||03/03/2022 22:21:02|
|2192 forum posts|
I've used G96 bluing creme. Wash the steel to remove all oils in hot water and detergent, rinse well, dry and apply the gel with a brush. Wash again and keep applying till you like what you've got, then oil up.
The cannon in my album was done that way.
1430 forum posts
Shotgun barrels that are blued will rust if not kept lightly oiled so don’t expect it to prevent corrosion if it it gets damp or wet. Dave W
|Grindstone Cowboy||03/03/2022 23:07:40|
|859 forum posts|
Copied from a reply I made to someone about a year ago...
Been doing a bit of cold blueing of Myford ML7 parts. I've previously tried a Jenolite paste blue which did work, but not a great finish, so I splashed out on some Phillip's Cold Blue Solution and I'm much happier with the results. Method used is as follows:
Immerse part in general purpose thinners (modern equivalent of cellulose thinners) and shake it around for a bit to degrease.
Remove from thinners with tweezers, wipe with paper towel and hold in the flame of a blowtorch for a few seconds (until any condensation disappears).
Immerse in solution - I used about 1 part blue to 2 parts tap water - and then, what I think is the most important part, keep brushing all surfaces with a new, clean paintbrush.
Keep doing this for at least five minutes, I went as high as ten minutes on some parts.
Remove from solution, dunk in clean cold tap water.
Remove and spray with WD40, then use fingers to liberally coat all surfaces with new motor oil (20W50 as I had some handy, not synthetic).
Leave for about 24 hours, wipe dry and apply a thin coat of Renaissance Wax with fingers, wait a few hours and buff with soft cloth.
Lovely dark blue, almost black finish that seems to improve slightly over the next few days. I think the heating and brushing are the key points to make it work well.
|John Ockleshaw 1||04/03/2022 03:00:28|
53 forum posts
I find Duncan Webster's hot solution of Sodium Nitrite and Caustic Soda gives a very durable BLACK finish rather than blue, you often see it on pliers and other tooling. It is not like blue lagging sheet.
|Gary Wooding||04/03/2022 10:10:50|
|983 forum posts|
I've had success with a product called 'Super Blue' made by 'Birchwood'. It can also be used to give an aged look to brass.
|Mike Hurley||04/03/2022 10:19:34|
|314 forum posts|
Gary - that looks good & fairly easy to use according to what I've just read on their website. The chemical system I use at present has about 4 bottles and although straightforward does take some time, and fiddling about with containers etc. Does it give a reasonably long-lived finish?
|1510 forum posts|
Different Oxide colours obtained from Muddle Ingineers Handbook heat application never failed me, but as a rebel, kitchen oven AFTER Sunday roast was/is invaluable as a constant heat source for dangling CLEAN bits from the racks and then dunk in gear oil.
|Gary Wooding||04/03/2022 12:23:46|
|983 forum posts|
Mike, the pieces in the photo were coloured in early 2021 and still look fine despite living in a very slightly damp cellar workshop. In fact I can't see any change from the day I did it.
|Howard Lewis||04/03/2022 12:25:34|
|6120 forum posts|
FWIW, in my experience, once the steel is clean, it should be treated immediately.
It seems to start oxidising immediately.
The various parts for my Worden cutter grinder were cold blacked, but after about 20 years some of it is beginning to wear off, and show small patches of rust.
Blacking plus oil seems to be the way to resist rusting.
As long term protection, Lanolin is excellent, but remains sticky and needs to warmed to make it more easily spread. Mine came in a tube, many years ago from Chronos.
|bernard towers||04/03/2022 12:26:27|
|619 forum posts|
Don’t understand why people insist on using motor oil as a protection against corrosion it’s useless. Use a oil that does not emulsify like tag or hyd oil.
|Lee Rogers||04/03/2022 17:17:03|
173 forum posts
Yes beats me too , not to mention the nasty fumes. I use Halfords hydraulic jack oil which is also my oil for the Admiralty Drummond lathe main bearings.
|Mark Rand||04/03/2022 19:35:50|
|1275 forum posts|
When oil bluing, one is looking to produce a layer of oxide and carbon on the part. Old motor oil does the job very well.
Corrosion protection is performed with other porducts.
1155 forum posts
Hi here is a video I came across a while back, I have never tried the method but see no reason it should not work, I do use rust blueing but a much longer process, **LINK**
All the cold blues are similar and based on the same chemicals, they work OK on smaller items but none offer particularly good rust prevention, better than nothing but traditional rust bluing and hot bluing offers a better protection, rust bluing being the better IMO. However iron + H2O always = rust !
|William Chitham||05/03/2022 17:34:59|
|139 forum posts|
Plus one for Phillips Cold Blue. I use a similar process to the Grindstone Cowboy except I give parts a preparatory scrub with detergent and I warm the solution by standing the container in a larger bath of hot water while bluing (bain marie?), and I give the parts a rub over with Mansion House polish which produces a nice finish. Don't know about the rust inhibition but makes them smell nice for a few days. You can see the finish on this parting tool holder:
|Andrew Tinsley||05/03/2022 19:00:47|
|1630 forum posts|
The molten Sodium Nitrate , Sodium Nitrite and Sodium Hydroxide mixture gives superb results and I have never had problems with rust afterwards. Not every one's cup of tea from a safety aspect, but extremely effective.
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