[TheForge] Oxy/Propane reprise

[Rick Korinek]

One thing that Ralph Sproul taught me is to clean up the surface where you
are going to start the cut.  The other is cut cool, that is to keep your
torch moving once you get a puddle.

-Rick
 

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of Paul N
Sent: Tuesday, November 10, 2009 8:59 PM
To: Blacksmithing List Sponsored by ABANA
Subject: Re: [TheForge] Oxy/Propane reprise

Well, I managed to gather my stuff together for a brief trial tonight, 
following the advice of the group. While I'm still not completely 
satisfied with my technique, I was much happier with the result.

Once I got going, I was probably moving at perhaps as much as 15"-20" 
per minute (far cry from my earlier attempt) and my cut was a LOT cleaner.

I still need to get a little more familiar with the flame/cone pattern.

I was trying to get a set of sharply defined preheat cones, but at that 
mixture, the tip was popping fairly frequently, so I richened the 
mixture a bit. I think I may have been hitting the gas valve while I was 
cutting, because that re-occurred a few times, and I had to repeat the 
process. As it was, while the flame was completely blue, the cones 
weren't what I'd refer to as "crisp", and were a little fuzzy. Still 
quite a bit shorter than what I think I recall from using acetylene.

I was on a time crunch (only had about 1/2 hr for setup, cut and 
cleanup), and didn't have time to make more than a couple cuts, so I 
still have some more practicing to do, and I still didn't do anything 
about the rust. While it seemed to slow the initial preheat, I found 
that I could start cutting before I got what I'd consider a good red 
heat all the way through the piece.

Thanks for the hand-holding.

**Paul

Peter Fels & Phoebe Palmer wrote:
> 
> Paul N wrote:
>> probably based in the assumption that I knew what I was doing :-)
> That helps me make my mistakes.
>> I looked back in the earlier messages, and yes you did raise that issue. 
>>   But I don't think I quite understood the mechanics, and probably still 
>> don't. I hadn't had an opportunity to drag my stuff out again yet, and 
>> my wife has this thing about my lighting fires in the house.
> \What's-a matter her?
>> I'm still a little unclear on the 2 O2 valves. I had assumed that the 
>> bottom valve controlled the mixture of the preheat, which left the other 
>> for the cutting jet. Obviously, that's not the way it works.
>>
>> I'd been looking for a schematic of the torch "plumbing" to help me 
>> understand it better. While I only spent a few minutes web searching, I 
>> haven't found anything yet.
> Paul; when you plug in the cutting attachment, O2 control is shifted 
> from the torch butt to the cutting attachment. The torch butt valve is 
> opened up wide and left that way.
> Mixture adjustment for the preheats is done at the cutting attachment 
> for O2, with the oxy lever depressed.
> I suspect you'll find you don't need quite as much O2 regulator pressure 
> for that thickness steel, either.
>
...
> ______________________________________________________________
> TheForge mailing list
> Home: http://mailman.qth.net/mailman/listinfo/theforge
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:TheForge at mailman.qth.net
> 
> TheForge mail list group photo site is
> http://www.photoaccess.com
> Login: blacksmithblacksmith at hotmail.com
> Password: anvil
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> 
______________________________________________________________
TheForge mailing list
Home: http://mailman.qth.net/mailman/listinfo/theforge
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:TheForge at mailman.qth.net

TheForge mail list group photo site is
http://www.photoaccess.com
Login: blacksmithblacksmith at hotmail.com
Password: anvil

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html