I do color case hardening of rolling blocks, single shot boys rifles and anything circa the turn of the 19th century.  My usual source for charcoal (Brownells) has been out of stock for about a year. I recently made my own bone charcoal from cattle ribs.  I also made some char from apricot pits.  The wood charcoal I used was from hardwood lump charcoal.  I pound the charcoal and then sift it through a 1/2" screen, rejecting the larger stuff for more smashing.  Finally I screen the charcoal with a fine mesh screen to separate the charcoal powder.  The mix of charcoal is 1/3 of each type.  It's a laborious process.  A pic of the latest effort is attached.
Processed charcoal can be obtained elsewhere, but shipping is not cheap, nor is the charcoal.  Conversely, I am frugal (cheap)!  I can make more, but it would be nice to re-use what I recover from the barrel I quench with. 
My question is, can previously used charcoal be re-used with little loss of coloration on additional go-rounds?   

To answer your question about reusing - I dumped my quench  water into a couple 5 gallon buckets, scooped out the used charcoal, spread it on a couple of cookie sheets and let it dry.  I reused my water which was distilled originally and I did the pack with the re-dried charcoal.  I did add a little bit to it to finish the pack.  Here's a photo of the last Ballard from this event.  I think it was a little more enhanced the second time around...  My first go was on a high wall and I didn't get quite the assortment of colors as the Ballard.

I charred bone meal for bone charcoal, fill a new, empty gallon paint can about half full, poke a hole with a 16 penny nail in the lid, cook on the barby  low heat for about 4 hours, shake frequently - did the same with hardwood blocks and I did another can with peach pits, choke cherry pits, leather gloves and boots that I shredded.  The odor from the bone meal is horrendous and the other ingredients being charred help mask this smell a little but it will gag most.
On this last one, I also purged my water with straight oxygen for about 5 minutes before the quench.
my 2¢
Greg

I use new charcoal for the anneal cycle, then use the charcoal from that for the color hardening.
Bone charcoal comes from Ebonex in MI, if I remember correctly.

idjeffp,

This is probably the thread on case hardening that you were referring to:  (You need to Login or Register to view media files and links)

Thanks to all for the info.  I really like GT's advice on bone meal.  I will have to pick some up and give it a try.  I wish they had a coarser grind but I love the colors GT got!

fishoot, the colors that you obtained on the Remington rolling block are very attractive to me, nice work!

japcas wrote on Apr 16^th, 2023 at 8:17am:


Generally all that is left after the case treatment is stoning a surface or two for mating purposes.  Some folks treat the metal with a poly or finish of sorts, I'll wipe it down and coat it in a simple oil and let it sit for a few hours - it's finished.

fishoot,
I can't really determine whether the pack gave me the reds and extra colors, it's "loud" and this action has faded some to where it's a little more tasteful now.  It is a casting from Rodney.  There's a full oven of projects currently getting ready now so if it doesn't highjack your thread, I'll post pictures? If I remember... 

I have done a few others, some with even more reds and yellows.  One of the secrets that seem to enhance the bright colors is the addition of O2.   My altitude is nearly a mile high and without it, I get mostly blues and browns.  An oldtimer told me once that charred leather introduces lighter colors but until I did the O2 nothing changed.  Temperature has a considerable effect also.  I'm not chasing hardness as much as color, for the high wear areas, I'll case specific areas with "Cherry Red" or Kasenite before doing the color process and I've had some luck with that.   At my altitude I've settled on 1325°F for the process and it gives me the best results.
another 5¢ worth of info.
Greg