Guys, (longtime lurker here)
I thought you might be interested in some metalworking content:
These photos are from Red Top Mountain State Park's "Hills of Iron"
program back in March. We gathered and roasted local limonite, made
charcoal, built the furnace, and forged iron bars. We've done it 3 times
now, successfully. Batting 1000.
I finally got around to making a webpage...no captions, but the images
are a sorta timeline. I Hope the page is somewhat viewable; I'll answer
questions if'n ya'll got em.
Demo smith and Ironmaster, Red Top
Fascinating stuff! Just added it to my links list. I hope you go on
recording your work.
Does the end result exhibit grain, like traditional wrought iron? Or is it
more homogenous like modern mild steel? What is the final carbon content
like, pretty low I'd assume?
Carbon content is low, as evidenced by the ability to hammer a bar.
We have not spark tested nor micro-looked for grain. I tell visitors
it'll penetrate your bronze armour. I do have photos of a cut and
polished section: it shows the usual embedded slag and porosity of the
bloom. I'll try to post that as well.
It's "Charcoal iron", from local rock. And trees
Ditto, I'll have to catch it after midnight I guess...
That's what you get for posting your link on RCM, Dave. <g>
"California is the breakfast state: fruits, nuts and flakes."
I got on - nice set of pictures that is for sure.
How many days did you cook wood for charcoal ? I would guess a number
for that melt and for home.
Nice to take material out of the local forest and come up with something
that you can work with and improve. Real metal.
@ home at Lion's Lair with our computer lionslair at consolidated dot net
I seem to remember reading that the vapors from charcoal making are used to
provide the heat to make the charcoal. It looks like your vent is on top.
Have you tried it at the bottom to use the vapor as fuel?
Have you made anything from the steel?
I finally got through!
My first impression is that this is by far the most attractive looking
catalin forge which I have ever seen. Whoever did the rock work on it
is certainly a first class mason.
I first learned about the bloomery process from Thomas Powers, who is
one of the "gurus" at the Anvilfire forum. I am sure that he will want
to take a look at these pictures.
I understand that there was once a time when making and working wrought
iron was what blacksmithing was all about, and that blacksmiths still
prefer wrought iron to steel, because of its superior working
Thanks for the feedback and patience; I'm not sure how many hits
Bellsouth takes before the Bwidth is exceeded. Meantime I'm leaving the
pics up so that, well...."Diffusion of Knowledge" and all that.
Answers to questions... A 55 gal.drum of @ 200lbs of seasoned oak
yields about 70 lbs of charcoal. There is a loss to powder and fines in
crushing and screening of about 15 lbs. We save this to make
"lute"(?)...clay/sand/ash/charcoal powder mix to re-line the furnace.
Powder can also be mixed with water and starch or molasses to form
briquettes of any size. Or...pyrotechnics!
The active cook time of the barrel is about 3-4 hours. The pics show
the different phases of the process...from 15 minutes after lighting up
till about an hour, fluffy white/gray steam exhales, which changes to
steam/blue smoke. Blue smoke then dominates, rushing out through the
holes in the lid (@6 SQ inches) with greater intensity until the gasses
ignite. Ignition takes about an hour and a half, plus. At this point, we
are Colliers, and we keep the heat to the barrel. It'll roar, and this
gas can be piped underneath for more efficiency.
After 4 hours or so, I lay on a last charge of wood fuel and cover
everything with sheet roofing, seal the holes at the bottom with dirt,
and go take a shower. The metal holds the heat in and reduces the burn
rate of the fuel so that final cook time is longer. 12-14 hours later
the metal covering is removed and any remaining fuel coals are scooped
into another drum and sealed. This makes our preheat charcoal, as it is
pine we use for fuel, and not as good for smelting.
The stone used to make the furnace is mostly schist taken from 300
feet away, and 30 feet downhill along the lakebed. Using a wheelbarrow,
these rocks were EXPENSIVE! there is some local "Corbin Gneiss" as well
as Tennessee fieldstone/limestone left over from other park projects.
The furnace was first fired using vitrified clay thimbles as liners.
Second firing we used refractory gasket rope and 5 gal metal
buckets...this was all done on the fly, as I'm a volunteer, and we used
what we had.
The furnace now has a permanent liner of a product called "Kruzite
castable". We formed it using 8 inch and 12 inch sonotubes. We lined it
with the aforementioned lute, and that works well to keep molten stuff
from adhereing to the walls. The shaft size is 8 inches diameter and 37
inches tall. The tuyere opening is 1-7/8 diameter and 10 inches above
the base. This is permanent in kruzite, and allows for modification of
sizes/configs. I built it overlarge to be able to "build down" and
experiment. Packing clay to raise the base,config the taphole ETC.
Blower motor was found in an RCM'ers junquebox <G>, as well as most
other hardware/plumbing. Peephole is local mica sheet and a ring magnet
on a tee. Elegant.
I posted 2 pics that should have been on the clunky website to the
Look for "Bloom.Txt" and "Bloom9011/Bloom8443"
Hi Dave, nice site. Regarding the bandwidth issue, the problem is not the
number of "hits", but rather the quantity of data (measured in bytes) that
is downloaded by your visitors. I looked at your site last night (between
"bandwith exceeded" errors) and noticed that your large images are very data
"heavy" (i.e., they have very large data byte sizes).
To reduce the problems with "bandwidth exceeded" errors, you need to
optimize your photos so that they are not so data "heavy". You see, there
are two parameters when discussing the size of digital images: there are the
pixel dimensions (e.g., 800 x 600) which specify the viewable ("physical")
width and height of the image; and there is the data size which specifies
the amount of bits of information (measured in bytes, or 8 bits) in the data
file that represents the image. (The problem you are experiencing is in this
latter category.) Typically, there is a correlation between these two specs:
a "physically" larger image (in terms of pixel dimensions) generally
requires more data (bytes) to represent the image than does a "physically"
smaller image. But there is another relationship between these two
parameters: quality which determines how much data is used to convey a
particular visual artifact within the image. To express this as a simple
equation, you'd have:
dimensions X quality = data size
So there are two ways to reduce the data size of your images (so your web
server does not exceed its bandwidth limits): reduce the pixel dimensions or
reduce the resolution (or both). Most people like to see larger images, so
we'll focus on reducing quality. Here's where the magic happens.
The human eye is an amazing device, but it is not designed to perform
quantitative analysis of an image. In other words, it looks at patterns and
colors and shapes, but does not individually analyze minute differences in
adjoining pixes. So if two adjacent pixels in an image are very close in hue
and/or saturation, we can make them identical and the eye won't be able to
see the difference. In other words, we've (intelligently) reduced the actual
quality of the image (less data), but the subjective quality -- what the eye
can perceive -- is undiminished. And that's how image optimization programs
work: they first reduce the amount of differences in the pixels of the image
(so there is less image data to "describe"), and then they use mathematical
algorithyms to further "compress" the data so that even less bytes are used
to represent that image. Here's a simple example of a compression technique:
If your image data is: 11111100011110000
You could compress that to: 6x1,3x0,4x1,4x0
That simple example may not look like much of a savings, but the reality is
that tremendous data compression can be achieved with these kinds of
Ok, perhaps you don't want to know all the nitty-gritty that goes into
digital image data compression. But here's what you should know: by using an
image optimization program, you can take an 800 x 600 pixel image that
"weighs" over 200,000 bytes, and compress it so that it only requires 20,000
bytes (for example). That will reduce your web server's bandwidth load by
90%. And the optimization programs are so good, that the human eye probably
won't see much -- if any -- loss of quality (especially when that image is
being viewed on a computer monitor). Of course, the more you compress the
image, the more the visual quality of the image is reduced. But you can
substantially reduce the data size of an image before it starts to look
There are a number programs to perform image optimization. I use Adobe
Photoshop, but that is (an expensive) professional-grade graphics tool.
There are some programs that are free and will do a fine job. Since I don't
have a lot of experience with these other free or lower-cost programs, I
can't make any recommendations. But people have mentioned IrfanView as a
I hope this helps.
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