[TheForge] Re: reducing fuel costs by improving forge efficiency.

[Jerry Frost]

I have no doubt you can get welding heat, I'm counting on it in fact, it's
just a burner size / forge volume ratio equation after all. This type forge
is basically a brick pile forge with all the advantages and few of the
disadvantages.

Still, nothing wrong with trying to improve burner efficiency with a
recuperative system. I'm designing a heat exchanger into the heat shielding
on my forge and it'll serve as a windbreak for the burner intakes. My design
differs from yours in that I'm going to place the burners horizontally
through the jack side, sidewall. To help keep the jack, fuel lines, valves,
gages, etc. cool I'll use a double wall sheet metal shield. It's double wall
so the burner intakes can be inside to take advantage of air preheated by
waste heat.

The utility in this type forge is the adaptability so things like casters,
shelves, helpers, built in tool racks and whatever else can be added without
getting in the way is a plus. My problem will probably be in trying NOT to
pack too many bells and whistles on it. <grin>

Durability is also an issue. Seeing as these forges have the capacity for
large, heavy items, facing the firebox with something tough is essential.
The table is easy, the lid is another matter. Generally, tough is heavy and
I'd like to keep the lid as light as practical.

I've had good, REALLY good luck with double liners in propane forges.
Specifically a high phosphate rammable refractory inner liner and an
insulating outer liner of Kaowool. This works really well in the pipe forge
but I'm not sure how well it'll work for the large flat hanging structure of
the forge's lid. In the pipe forge the inner linner, being tubular is pretty
much self supporting and simply beds in the Kaowool. The flat lid of the
planned forge however, will require internal support as the hard refractory
isn't likely to support itself on a flat span. Another factor is heat
expansion over a 24" x 36" flat expanse so using Kaowool for the insulation
may not be the best bet. Not because it doesn't insulate well enough but
because it has no tensile strength and will do nothing to help the hard
liner. I'm thinking of making up a batch of perlite/fireclay/cement
insulating refractory and tieing the hard refractory inner liner through it
to the steel lid shell shell with SS screws. Another option would be to use
the Kaowool hardboard (don't recall the name) and ramming the hard
refractory inner liner, with screws, to it. It'd be expensive though and I
have more than a bit of the Scott in me. <grin>

Frosty
------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.


----- Original Message -----
From: "Ralph Sproul" <brhlbsmt at mcttelecom.com>
To: "Sponsored by ABANA" <theforge at mailman.qth.net>
Sent: Monday, July 26, 2004 3:22 AM
Subject: Re: [TheForge] Re: reducing fuel costs by improving forge
efficiency.


>         Frosty,
>         Doug claims he can place two bricks six inches apart from the
center
> of the burner and forge weld with it.  I haven't tried that - but it works
> for him.  I guess that covers the topic of improving forge
> efficiency.........We move bricks......not try to suck hot air upon
intake.
>
>         For the size space it will heat compared to what I use it for most
> of the time, this works well on one burner with the idle incorperated when
> talking, phone, layout, etc.
>         When you need to heat six to eight items with a 20 inch
> heat.........then your talking heavy gas consumption(about $60-100 per
> month) for the work I do - which is mostly railings.  I just consider this
a
> cost I take in stride with the business of making iron work.
>
>         Adaptability is where these unit really shines.  One burner or
> two.......the side walls changed from any configuration..........(as long
as
> the side towards the burners is left in). I love being able to work on a 4
> foot radius to an arch of a gazebo or rose trellis arch...........just try
> that in a pipe forge!  The pile of bricks on a table is an idea which you
> just can't argue with (Thanks again for those tapes Clifton).
>
>         The nice thing about those side arm burners you suggested I
make( a
> couple years ago).......is they tend to be somewhat windproof.  I like
just
> puting large parts on the Acorn table and heating them with a firebrick
> under them............that takes away the handling of heavy objects while
> hot..........you just do it where it sits, by prying it up and sliding the
> bricks out to use the jig table it's on.  Beats trying to muscle a 3/4 x 1
> 1/2 flat that's 5-10 foot long for a railing section in and out of the
forge
> to get the work done.  My goal was to work on large projects without
needing
> to hire help - it works.  I think it's a good stopping point as compared
to
> going to huge rosebuds with high oxygen inputs required to move large
stock.
> There is a point working by yourself, that you have to stop - on size of
> material and cost of heating.
>
>         After looking at Marc Godbout's forge site with the light weight
> refractory in the domed top.........I can see this would be a really nice
> option for another version of his  and my lift top sytle forge. I would
like
> something more durable than the Kaowool board for a ceiling, and the domed
> shape may have some added benefits.  I'd keep the caster table I've got,
> allow it to still pivot, the hard brick floor for durability, and
insulating
> high temp bricks for the sides, and then put the formed lid with
refractory
> on as a top.
>         The caster table and jack post become really handy sections of the
> forge as a tool rack.  The base not only allows the unit to be stowed away
> and come out when needed, but the storage off all size bricks (and broken
> bricks to act as diverters and heat shields) is great to aim and localize
> heat.  The jack post has a rack to hold the reach in poker, the small pick
> up tongs, and the larger two radius pick up tongs for moving any object
> around or flipping them to get the heat to soak into large items, and the
> handle on the side is where I keep the brick tongs for moving the hot
> bricks.  So it's a totally self contained tool, with all the accessories
> rolling around with it - when it's needed.  I see Marc went with what he
> had, and incorportated the ideas of rolling cabinet and lifting the lid
with
> a mechanical mechanism (scissor jack) to change the firebox when it's hot.
> When you do your clamshell (if you have a cement floor in your shop, that
> is) - I'd keep casters, pivoting tower, and mechanical lifting top on the
> list of priorities for your design.
>         This sounds like a winning combination for your clamshell.  Right
> now I'm so loaded with work that my spare time is going to working on
> rebuilding the 3B I picked up last summer.  If you get a chance to make up
> your clamshell this year, I'd love to see the results you get.  Your
designs
> have always impressed me, and led me to some of the completed projects
I've
> got now.  ( I've still got that swage stand drawing I want to get to some
> day!)
>
>         Marc and I have talked with a fellow in Rhode Island who wants to
do
> a workshop on burners and gas forges later this fall.......this might be a
> nice time to make one "experimental unit" while there are 8 - 10 guys
> looking to keep busy on a group participation project.
>         After making 9 different style (trial and error) burners to get to
> the one's I like now.........I can see why I get all the e-mails and phone
> calls from members of our club experimenting with which burner to run
with.
> I think a workshop and newsletter article will clear up a lot of questions
> for the folks working on gas forges.......besides being a great way to
spend
> the day with a bunch of good folks.  :-)
>
> Ralph
>
>