FW: [TheForge] oxy-propylene, propane tips and air-arc

Sun Jun 24 19:16:14 EDT 2007

-----Original Message-----
From: Kathy [mailto:keporter at comcast.net] 
Sent: Sunday, June 24, 2007 3:18 PM
To: 'Sponsored by ABANA'
Subject: RE: [TheForge] oxy-propylene, propane tips and air-arc

Ben,

I'm a little confused; it seemed that the discussion was on torches, which are
either used for cutting or for fusion welding by most blacksmiths. I now realize
that you are thinking more along the lines of general heating within forges, and
specific heating jobs in special fixtures outside of forges, is this correct?
For such work, I would not use any of the more expensive fuel gases (ex.
propylene). Your conclusion is correct in this context; go with a miniforge.

As to your question on whether or not I can "expound on any reasons *against*
using non-enriched compressed air with propane," it's not an either or choice.
Think of oxygen enrichment as the equivalent to an after burner on a jet plane;
not something you use all the time, but very nice when you want to "get the h**l
out of Dodge." Also, enrichment is necessary to the successful employment of
fuel temperature boosting products like Chem-O-Lene. 

The way oxygen enrichment works is that a venturi mixer is connected to your
compressed air line. You don't have to use it all the time. You don't even need
to install it during the original construction process; it can easily be
retrofitted into the air line.

However, using enrichment may call for other changes:

You would probably want to use bubble alumina as your refractory, at least in
the area of flame impingement. You would also want to build the forge nozzle
shape into the refractory rather than using an SS nozzle. Otherwise you are
going to melt the nozzle right off the burner's end. Finally, look at this site
for torch equipment appropriate to your stated interests--pay particular
attention to their line of torch tips: http://nationaltorch.com/index.html  

Any more questions?

Mikey

-----Original Message-----
From: theforge-bounces at mailman.qth.net [mailto:theforge-bounces at mailman.qth.net]
On Behalf Of Ben Barrett
Sent: Saturday, June 23, 2007 12:24 PM
To: Sponsored by ABANA
Subject: Re: [TheForge] oxy-propylene, propane tips and air-arc

Thanks Mikey -- I'm just not convinved from what I read here that propylene

will make things any easier for me.  The idea with propane and compressed

air is based on the amount of BTU's I observe being cranked out of either of

the venturi forge burners I have now, as well as my buddy's forced-air propane

forge... I am also consider just making a mini-forge, since that could

cover many

of type situations where I want a more focused heat (more cheaply).

Definately not made of money here, but prolly better-off than many folks...

I've almost wiped out my tool budget now, and the biggest items I've come

to acquire are the anvil ($200) and oxy/acet setup ($300), and I can't afford

any bigger-ticket items until I get some nice commissions :)

I figure a $500+ job would enable me to upgrade my torch setup

in some way, so I'm trying to figure out if I should save up for the All-States

or some other propane-specific torch... I need a bigger oxy tank if I'm going

to use any substantial oxy, so that is an additional cost for me.

I'm more inclined to rig up some kind of [mostly-] fixed burner, with

an insulative

baffle maybe, to do point heating with.  I still need all the

experience I can get

with the oxy/acet, I learn a lot each time, but it is not worth

burning up unless

I'm progressing on some project, it seems.

BTW, can you expound on any reasons *against* using non-enriched compressed

air with propane?  Again, no cutting needed/expected for that setup.

Does it just

not get rich enough of a mixture, before it blows out the flame?

Then, what about

using something like the classic hair-dryer blower with a small

home-made burner,

maybe on some sort of swing-arm frame (since I'd prolly over-build it

too much to

be handheld :)  -- sound feasible?

One thing I'm still trying to understand, is how I might creatively

deal with all the wasted

heat, from both forge and torch.  Would working a torch within say a

3-sides insulative barrier

help, or would that just be too unbearable, kicking back all the heat?

Sorry for all the questions.  TheForge is so helpful, thanks everyone!

ben

On 6/22/07, Kathy <keporter at comcast.net> wrote:

> Ben,

> I'd make that propylene and compressed air if you're going to delete oxygen
use,

> or  try oxygen enrichment of the compressed air. You can get venturi mixers
for

> enrichment from Carlisle Machine Works (you might just want to check out the

> Unicon Hand Torch while visiting their site, unless you're made of money that
is

> :)

> Mikey

> 

> -----Original Message-----

> From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net]

> On Behalf Of Ben Barrett

> Sent: Friday, June 22, 2007 11:32 AM

> To: Sponsored by ABANA

> Subject: Re: [TheForge] oxy-propylene, propane tips and air-arc

> 

> So, propane has gotten a little more expensive since that

> All-S...whatever FAQ price comparison was written up, but clearly it

> could still be a big gain.  Right now I only have a couple small Oxy

> tanks, so I wouldn't want to over-use that.  For basic spot-heating,

> like fine-tuning twists and bends, can propane and compressed air be

> used?  That sounds like the right price!!

> I have a spare compressor tank (no motor or compressor) that I was

> thinking of setting up just for that purpose... I don't care if I use

> up a lot of compressed air, it is cheap :)

> 

> So, if no cutting is done, does compressed air work well enough with

> propane through an oxy/acet torch?  Should I still use tips made for

> propane?

> If this works, it would be an incredible boon, using mostly what I

> already have, which we can all appreciate.  Seems unreal.

> 

> ben

> 

> 

> 

> On 6/22/07, Ron Childers <munlaw2 at hcsmail.com> wrote:

> > A #2 Propane tip works pretty well on my big ol Smith torch that was made

> > for oxy-ace. It cost about 12-15 $$ and cuts rr rail ok. Once the metal is

> > hot it's the oxygen that does the cutting. The Allsnakes torch may be better

> > but I would have to be convinced to spend the extra $635 when my torches

> > work pretty well..

> >

> > I've had no problem switching from acetylene to propane and back again- not

> > enough mixing of gasses to matter by the time the regulator is swapped and

> > the torch is lit anyway.

> >

> > If you want to get nasty, quick & dirty, use an air-arc torch. Truly a

> > matter of function over esthetics. It isn't pretty but does the job.

> >

> > Ron C

> >

> >

...

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