[TheForge] Getting the lead out or the tar baby? - Take 2

[Steve Bloom]

At 03:54 PM 7/27/2013, Peter Fels  wrote:
> >>Peter: My guess is that you are not annealing often enough,or 
> cooling too abruptly,or overheating when you do anneal..

I don't mess with heat treat of the helmets - they are designed to 
resist shrapnel and little else.  They simply are a convenient 
shape.  Especially when annealed, the desired share will vanish, so 
that's not an answer..

> >>Peter: i'd recommend a solid steel dome stake of about the right 
> curvature to work against,

which is what the helmets are (but way more fragile).  If I could 
create hard wood 3D replicas of the helmets, I would be golden -- but I can't.

> >>Peter: Lead hammers have their place, and this probably isn't it. 
> Unless they are intended for actual combat, I'd respectfully 
> suggest starting with mild steel....

The hammers do work -- as do some of the helms I made 25 years ago 
still function. And they are intended for SCA heavy combat 
(effectively impacts from a baseball bat) but we have a 
misunderstanding here -- the army hats are the forms, the helms will 
be out of riveted 16-gauge mild steel (thus overlaps are essentially 
8-gauge). I just want to extend the life of the forms.

and....At 06:19 PM 7/27/2013, Mike wrote:

 >>Mike: Wikipedia says some had way more pieces than that.

Eventually -- the bowl is made of 8-plates overlapping to the rear. 
The shirokoro (neck guard) are usually 5 arched strips (or many more 
depending on the lacing) and there is the brow piece not to mention 
the tehen stack of washers and a really big grommet and a socket for 
the helm decoration and the mempo (or grill) etc.  But the base step 
is the generation of 8 plates that mimic the shape of a human head 
(with some padding - see above)

 >Mike: These are for-and-aft strips or radial segments to be riveted 
together to form the crown of the helmet?  And you're working the 16 ga. cold?

Exactly -- the pieces are symmetrical left-to-right with the frontal 
and terminal plates being unique -- so the three between are 
more-or-less sail shaped but repeat -- right/left temple, right/left 
middle, right/left side-rear though each one is different because a 
head isn't symmetrical (as I learned making my first great-helm - can 
you say grill-on-the-nose-and-acres-of-space-around-the-ears - 
destined for the slack tub).  When done correctly, the margins run 
radially from the top to the edge (doing a 32-plate unit is WAY more 
painful).  The plates are over dished in a Yater swage block to 
create the 3-D bubble, clipped into place over the preceding plates, 
then planished to mimic the helmet shape in that specific 
location.  The planishing has to result in the overlap with enough 
space to set 3/16" rivets (5 rows from edge to tehen)..

 >>Mike: I'd hammer a depression in a lead block, then use a 
combination of:  sinking the 16 ga on the block with a ballpeen or 
other  round-faced hammer and planishing over a solid iron/steel 
stake with frequent annealing. Probably that would require some final 
shaping over other stakes to get the joints aligned.

See above (we're on the same track) but the plates really do not need 
annealing.  My personal helm went through years of combat without a 
problem (maybe because I didn't get hit that often back then <smirk>) 
and the still-in-service ones are a quarter century in service w/o 
failure.  Heat was never needed and would really complicate the 
generation of the overlap needed.

 >>Mike: For one off, fill the helmet with a mixture of dry plaster 
of Paris and roofing tar. (Why PofP?  I dunno.  It's what a 
respectable jewelry/goldsmithing teacher recommended to his 
students.)  If you're doing a dozen or two, lead.

Right your are (a neuron or so fired up -- I use to know that -- but 
the ratio??) -- I'll do a search on "pitch bowls + tar + 'Plaster of Paris'.

Thanks for the assist -- eventually I drop pics on my web site.

Steve