Announcement: Another french gray product.

John B.

Lifetime Pledge Member
::::Pledge Member::::
Joined
Nov 9, 2006
Messages
3,950
Location
Los Angeles area, California.
FYI, thought I would share this with you.
I recently found another source of a fine French Gray dip material.
It is Phosphoric acid based material, rather like a mild, cold acting Parkerize material.
It will give reasonable rust resistance and show engraving of to good advantage but needs a sealing dip to do this.
I think you can see my sealing process in the Tips department if you care to try it.

"Du Pont Heavy Duty Acidic Tile Floor Cleaner."
Cheap and easy to find at Lowe's in the tile department, about $10.00 for a quart. Can be used over and over for steel parts.

This is a lot easier to find than the automobile body prep material that I previously used.

WARNING. As usual, care should be excercized in the use of any chemical product but I do not find this to be very hazardous if used with due caution, eye protection and gloves etc. Best to use a Pyrex or ceramic container, not metal to hold the liquid while dipping parts.
Store the material in it's original labeled container.
 
Last edited:

russ

Member
Joined
Nov 12, 2006
Messages
85
Location
Denver
Thanks for the info John. Is it custom to remove the blue, engrave, re-blue and then do the French gray or can you get by with graying the original blue?

Thanks
 

Doc Mark

~ Elite 1000 Member ~
Joined
Nov 16, 2006
Messages
1,284
Location
Hampton, Virginia
Hey John,

FYI, dentists use phosphoric acid to etch teeth before bonding restorations. I probably pay $500 a quart for the medical grade solutions and I wouldn't be surprised if the $10/quart stuff wasn't just as safe and effective. I would look into that if I wasn't afraid of law suits! He, he, he. Anyway, great tip on the French Grey, someday I'm going to have a project that could use it.

Mark
 

Sam

Chief Administrator & Benevolent Dictator
Staff member
Joined
Nov 6, 2006
Messages
10,489
Location
Covington, Louisiana
Thank you, John B! Sounds like an excellent product. I've added your post to the Tips Archive.

Cheers / ~Sam
 

John B.

Lifetime Pledge Member
::::Pledge Member::::
Joined
Nov 9, 2006
Messages
3,950
Location
Los Angeles area, California.
Thanks, Sam. Might be a help to some.

Doc Mark, I know what you mean.
Put the word "Medical" on it and the price goes through the roof.

Russ, thanks for the question.
No need to reblue. Just dip the clean, bare metal after engraving.

Eric, give it a go. I think you will like the result.
Just be sure to seal it to get a pretty durable finish.
 

John B.

Lifetime Pledge Member
::::Pledge Member::::
Joined
Nov 9, 2006
Messages
3,950
Location
Los Angeles area, California.
Hi Mike,
I use a very thin mixture of acetone with a little varnish added and applied by dipping.
Warm the metal with a hair dryer before dipping it.
Please do a little search in the Tips section for a fuller details or do a regular search in the forum topics using French Gray as key words.
Thanks for your question, Mike.
Maybe friend KCSteve will see this and post a link to it if he has time.
He is a great at doing that for us.
 

KCSteve

~ Elite 1000 Member ~
Joined
Jun 19, 2007
Messages
2,882
Location
Kansas City, MO
How could I pass up a request like that?

click here for John B's tip thread on French Gray

And here's the part on sealing:
AT THIS STAGE, WHILE THE PART IS STILL WARM, IT SHOULD BE
DIPPED INTO A SEALANT TO PROTECT THE FINISH.
THE SEALANT SHOULD BE MIXED, TESTED AND CONTAINED IN AIR TIGHT JAR,
AND BE ON HAND EEFORE STARTING THE FINISHING PROCESS.
MIX THIS IN A SCREW TOP JAR, SHAKE AND TEST BEFORE EACH
USE, KEEP IT THINNED DOWN AS NEEDED.
TO MAKE THE SEALANT SOLUTION, HALF FILL THE JAR WITH CLEAN
ACETONE AND ADD ABOUT A TABLESPOON OF SPAR VARNISH.
DO NOT USE PLASTIC VARNISH; USE THE OLD FASHONED ROSEN TYPE.
SHAKE TO MIX, TEST AS FOLLOWS.
TO TEST THE SEALANT MIX.
HOLD THE BACK OF YOUR HAND OUT IN GOOD LIGHT AND NOTICE THE TEXTURE AND LIGHT THAT
REFLECTS FROM IT. DIP A FINGER INTO THE MIX AND MAKE A QUICK
SWIPE ON THE BACK OF THE OUTSTRECHED HAND. THE WARMTH OF YOUR
HAND WILL IMMEDIATLY FLASH OFF THE ACETONE AND LEAVE A VERY
LIGHT DEPOSIT OF VARNISH WHICH YOU WILL SEE AS A SLIGHT SHINY
STRIPE ON THE BACK OF YOUR HAND. IF YOU DONT HAVE A STRIPE MIX A
LITTLE MORE VARNISH IN AND TEST ON A DIFFERENT PART OF YOUR SKIN.

AFTER GRAYING AND WITH THE PART STILL WARM FROM THE DRYER AND BEING HANDLED ONLY
BY THE WIRE, DIP IT INTO THE SEALANT MIX. REMOVE AND REDRY THE PART IN THE AIR.
HANG BY THE WIRE UNTIL FULLY DRY, 24 HOURS IF TIME PERMITS.
APPLY INK TO THE ENGRAVING TO BRING OUT THE DETAIL. REMOVE
THE EXCESS INK FROM THE FLAT AREAS WITH CLOTH DAMPENED WITH ALCOHOL.
AVOID FLOODING THE SURFACE, WIPE SEVERAL TIME WITH A JUST DAMP CLOTH.
LIGHTLY POLISH ANY DIMENSIONAL GOLD OR SILVER INLAYS WITH A SOFT ERASER,
STAY STRICTLY ON THE INLAY.
SIT BACK AND ENJOY YOUR HANDWORK.
 

Latest posts

Sponsors

Top