Marking-out blue: best recipe
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 37
  1. #1
    Join Date
    Jan 2012
    Location
    Sheffield, England
    Posts
    78
    Post Thanks / Like
    Likes (Given)
    165
    Likes (Received)
    79

    Default Marking-out blue: best recipe

    I have a bag a prussian blue powder and a bottle of ethanol. What is the best recipe for making marking-out blue? What ratio of blue to alcohol?

    Richard

  2. #2
    Join Date
    Mar 2001
    Location
    Switzerland
    Posts
    2,391
    Post Thanks / Like
    Likes (Given)
    1971
    Likes (Received)
    967

    Default

    Will this be for scraping work or something else?

  3. #3
    Join Date
    Jan 2010
    Location
    Indianapolis, Indiana, USA
    Posts
    5,474
    Post Thanks / Like
    Likes (Given)
    2426
    Likes (Received)
    917

    Default

    If the OP can't determine the proper ratios, the Prussian Blue is useful as an antidote for thallium posioning.

    Thallium poisoning - Wikipedia, the free encyclopedia

  4. #4
    Join Date
    May 2005
    Location
    Austin, TX
    Posts
    4,404
    Post Thanks / Like
    Likes (Given)
    1259
    Likes (Received)
    1188

    Default

    Prussian blue is a nasty mess. Assuming you mean spotting for scraping, Canode water-based spotting compound is what you want:

    Power Scraping Accessories & Aids | DAPRA

  5. Likes rpchristian liked this post
  6. #5
    Join Date
    Jun 2004
    Location
    Melbourne Australia
    Posts
    4,943
    Post Thanks / Like
    Likes (Given)
    616
    Likes (Received)
    1776

    Default

    He's in England. He will want the drying one for doing layout and scribing work on. Ethanol and blue powder. The problem is, once the alcohol evaporates, there's nothing to hold the pigment on. Nothing to stick it to the metal.

    Its almost before my time, but I recall old guys mixing there own with methylated spirits. (Denaturated. Alcohol in the U.S) shellac flakes, and powder to make a kind of varnish, that would stick and hold once the fluid dried off. Don't recall the recipe, it was just a splash of this with a splash of that until you were happy with it.

    Can you even buy shellac flakes anymore. I could be wrong but I think the non drying / scraping blue is called Engineers Blue in the U.K

    Regards Phil.

  7. #6
    Join Date
    Feb 2006
    Location
    SW PA
    Posts
    6,027
    Post Thanks / Like
    Likes (Given)
    1266
    Likes (Received)
    726

    Default

    You can also spend a dollar or two and buy either a little tube of Dykem paste, or a spraycan of Dykem. The tube stuff takes forever to dry out, the spray, within minutes.

    You WILL need cleaner to remove the spray after it dries.

    You can, of course keep on with your scheme to use up the powder. I am cheap, too. I probably would, but it would not be as convenient as the spray.

    George

  8. #7
    Join Date
    Apr 2006
    Location
    Manchester, England
    Posts
    6,394
    Post Thanks / Like
    Likes (Given)
    756
    Likes (Received)
    3269

    Default

    Depending on the size of work you are doing you can buy a sort of magic marker style pen these days. We buy them all the time, the tip is about 3/4" by 1/4" wide and the tube is about 5" by 1". They're specially made for marking out. Obviously they're not made for large castings but for small work and erasing in-correct lines on large work they're fantastic. Easy to use and the blue is good and dries very quickly. I just can't bring to mind the makers name but I can find out for you.

    Regards Tyrone.

  9. Likes Laurentian liked this post
  10. #8
    Join Date
    Feb 2013
    Location
    midlands,UK
    Posts
    2,947
    Post Thanks / Like
    Likes (Given)
    1457
    Likes (Received)
    1443

    Default

    20 odd years ago when I worked in a development lab with a small workshop we used to have a really bright blue "lump" that we bashed a bit off and mixed up with a solvent ,I'm not sure if it was ethanol or not, but I don't remember it to be an exact science. I assume the "lump" started out as the powder that the OP is talking about. I liked this stuff as it seemed to stay on the job better than the proprietory darker blue stuff.

    In the works where I did my time they used a white paint like liquid on the bigger jobs.

  11. #9
    Join Date
    Jan 2012
    Location
    Sheffield, England
    Posts
    78
    Post Thanks / Like
    Likes (Given)
    165
    Likes (Received)
    79

    Default

    Quote Originally Posted by Tyrone Shoelaces View Post
    Easy to use and the blue is good and dries very quickly. I just can't bring to mind the makers name but I can find out for you.
    Thanks Tyrone, that would be interesting to know.

    Yeah, using up the prussian blue was a cheap solution, but it's turning out to be very messy. As lazlo has pointed out, the alcohol evaporates leaving a fine, bright blue dust that transfers instantly to your fingers and then to anything you touch. In a few seconds you've covered your entire workspace in the blue smears. Don't recommend this. Anyone reading: stick to the spray.

    It might still be useful mixed with oil to make a spotting compound, or engineer's blue, as Phil points out. I'll try this out.


    Richard

  12. #10
    Join Date
    Feb 2007
    Location
    upton ma
    Posts
    1,638
    Post Thanks / Like
    Likes (Given)
    43
    Likes (Received)
    165

    Default

    In regards to one of the side question - Shellac flakes look to be easily available at least in the US (and it looks like some of the companies will ship internationally), price seems to be on the order of $30/lb +-

    Dykem layout fluid is available in red and blue, spray can as well as brush top bottles and wide felt tip tubes. 4oz bottle is all of about $6 from Enco, not sure on availability in the UK but hardly worthwhile to be making your own.

    Paul

  13. #11
    Join Date
    Sep 2006
    Location
    SE PA, Philly
    Posts
    5,076
    Post Thanks / Like
    Likes (Given)
    903
    Likes (Received)
    1564

    Default

    Perhaps this will help. Not sure that it's completely apropos, as prussian blue is insoluble in water. So I think you need something to keep it in suspension.
    ink.gif

  14. #12
    Join Date
    Oct 2004
    Location
    Lancashire, UK
    Posts
    1,283
    Post Thanks / Like
    Likes (Given)
    54
    Likes (Received)
    458

    Default

    The stuff that Tyrone is talking about is very good, but you can often get by using various sizes of 'Sharpie'. The small ones are only useful for small areas of course - you want the bigger ones for most things. They make marking stand out pretty well, but the drawback (a big one!) is that they will wash away with coolant, which could be inconvenient. Personally I wouldn't bother with any of the old witches brews. The newer ready made layout dyes are OK, but some of them can crack away from the lines that you mark - the marker pens don't do this. If you are doing layout on big castings then you need something else, but I doubt if this is you problem at the moment.

  15. #13
    Join Date
    Jul 2007
    Country
    UNITED KINGDOM
    Posts
    4,124
    Post Thanks / Like
    Likes (Given)
    1909
    Likes (Received)
    1674

    Default

    If you want to turn it into layout blue, mix it into some French polish or meths and shellac to a dark blue, water thin consistency. Spotting blue would use a very small amount of ISO 220 way oil with the blue thoroughly mixed into it. To be honest, in Sheffield, I'd expect to be simpler to buy layout blue in a number of handy engineering suppliers (there's two or three here in Rugby that carry it). Chronos as an example for mail order or Cromwell tools in Effingham St, Sheffield and mail order, spring to mind.

  16. Likes rpchristian liked this post
  17. #14
    Join Date
    Mar 2007
    Location
    Bozeman Montana
    Posts
    9
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1

    Default Big pens for marking

    Quote Originally Posted by Tyrone Shoelaces View Post
    Depending on the size of work you are doing you can buy a sort of magic marker style pen these days. We buy them all the time, the tip is about 3/4" by 1/4" wide and the tube is about 5" by 1". They're specially made for marking out. Obviously they're not made for large castings but for small work and erasing in-correct lines on large work they're fantastic. Easy to use and the blue is good and dries very quickly. I just can't bring to mind the makers name but I can find out for you.

    Regards Tyrone.
    Sharpie pen in various colors and styles

  18. #15
    Join Date
    May 2009
    Location
    Canandaigua, NY, USA
    Posts
    2,345
    Post Thanks / Like
    Likes (Given)
    96
    Likes (Received)
    849

    Default

    You seem like the sorts that would really like Henley's Formulas, Recipes & Processes. Try to find an old copy, say pre 1940s. Another good source of chemical goo is the Laboratory Arts & Recipes section of a good chemical engineering handbook like Lange's or maybe CRC. In this case older is better than newer. Not sure if they have the exact bluing formulas, but they have enough on paint and glues to get you started.

    Personally, I usually use a Sharpie.

  19. #16
    Join Date
    Sep 2004
    Location
    south SF Bay area, California
    Posts
    1,872
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    514

    Default

    sable --

    Did the "blue lump" solution you describe leave a blue film, or a copper film? One common layout fluid used in the days before Dykem was a fully-saturated solution of copper sulphite (commonly called "bluestone") in water, or sometimes in VERY dilute sulfuric acid.

    I have a slightly-clouded-by-time memory of a 1960s classroom demonstration, in which a walnut-sized lump of bluestone was crushed to a coarse grit, poured into a clean cough-syrup bottle, clean water was added to nearly fill the bottle, and then ten or twelve drops of battery acid. The bottle was then capped and shaken well, producing a clear blue solution with little chunks of copper sulphite on the bottom. When swabbed on a clean iron or steel surface, the solution deposited a copper film that clearly showed layout lines.

    John

  20. #17
    Join Date
    Apr 2006
    Location
    Manchester, England
    Posts
    6,394
    Post Thanks / Like
    Likes (Given)
    756
    Likes (Received)
    3269

    Default

    John, That sounds like the stuff we used to use for checking wether a component's chrome plating was still existing or wether it had been worn away. Regards Tyrone.

  21. #18
    Join Date
    Oct 2004
    Location
    Lancashire, UK
    Posts
    1,283
    Post Thanks / Like
    Likes (Given)
    54
    Likes (Received)
    458

    Default

    You see references to Copper Sulphate used for layout in old books, but really I think that it has gone the way of read lead and oil paste for scraping, white lead for centres, horse dung for casting bronze etc. Maybe someone still uses these somewhere but there are much simpler and safer (and less smelly) modern options.

  22. #19
    Join Date
    Jun 2012
    Location
    Minnesota, USA
    Posts
    1,866
    Post Thanks / Like
    Likes (Given)
    337
    Likes (Received)
    666

    Default

    Quote Originally Posted by machtool View Post
    He's in England. He will want the drying one for doing layout and scribing work on. Ethanol and blue powder. The problem is, once the alcohol evaporates, there's nothing to hold the pigment on. Nothing to stick it to the metal.

    Its almost before my time, but I recall old guys mixing there own with methylated spirits. (Denaturated. Alcohol in the U.S) shellac flakes, and powder to make a kind of varnish, that would stick and hold once the fluid dried off. Don't recall the recipe, it was just a splash of this with a splash of that until you were happy with it.

    Can you even buy shellac flakes anymore. I could be wrong but I think the non drying / scraping blue is called Engineers Blue in the U.K

    Regards Phil.
    You can still buy BullsEye premixed shellac. Just add some of the Prussian Blue to the shellac and see what it looks like. Since you aren't trying to use the shellac for fine woodworking, age won't make much of a difference.

  23. Likes mike 44 liked this post
  24. #20
    Join Date
    Jan 2002
    Location
    Upstate NY -In the Flats next to the corn fields
    Posts
    8,651
    Post Thanks / Like
    Likes (Given)
    1280
    Likes (Received)
    2106

    Default

    Dykem by the bottle or spray can is relatively cheap, but it goes bad with age
    and becomes mostly transparent in time. I hate throwng out most of the
    hardly used bottle or can after 2 years.

    dk


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •