[TheForge] Oxy/Propane reprise

[Peter Fels & Phoebe Palmer]

Paul:
That travel speed was much slower than it should be. Try tilting the tip 
in the direction of travel once the cut is started.
Adjust the torch when the oxy lever is depressed. There should be little 
or no feather. Crank the preheats up so you can proceed faster..go as 
fast as possible without losing the cut.  pf

Paul N wrote:
> Thanks Ben,
> There's no question that the wind was a factor, as the torch blew out a 
> few times with a gust of wind. I'm still a little unsure of how my flame 
> profile should look. I was setting the mixture so there was little of 
> what I would call an "acetylene feather" of I were using acetylene. But 
> those cones in the preheat flame were mighty small, maybe 1/8" to 3/16".
> 
> I was successful in cutting my circle, I just had some difficulty a few 
> times. Actually, now that I gave it some thought, that I did cut about a 
> 90" long kerf, and while I don't know how fast I was moving, if it were 
> about 3 inches per minute, that's still about 30 minutes of continuous 
> cutting. And there were segments where I was actually moving along 
> pretty well for an inch or two before I got a little ahead of my heat 
> and had to pause.
> 
> And I know I was going pretty slowly, particularly when I got "near the 
> end" and was worried that the change in balance was going to make the 
> thing move alot, so I was a little more outstretched, and consequently 
> less steady with the torch. (As it turned out, the work was sufficiently 
> secure, and as the cut completed, it didn't move much)
> 
> It'll be a good week before I get a chance to try again. Gotta devote my 
> saturday this week to the UMBA fall meeting. At least I have a more 
> manageable piece to practice on now. A 4'x4'x3/8" piece is not that easy 
> to move around :-)
> 
> Thanks again,
> **Paul
> 
> 
> 
> Ben Barrett wrote:
>> Hmm.  My setup is almost identical to yours, and I have had good luck,
>> although there are some differences:
>> * I run my torch in a wind-free environment.  My own movements are
>> visible in the pilot flame of my fuel-saver, but not on the torch at
>> all.
>> * I have a smaller tip, #0/"aught" IIRC, but still a victor
>> oxy/propane tip on a clone torch body.
>> * I tend to keep my propane regulator around 3-5 PSI, and the oxy
>> around 20-30... sorry for the range here, but I honestly don't know
>> how accurate that is anyway (is an acetylene regulator but was new).
>> When the tip was new, I got about a 30" long flame, much longer than
>> anything I had seen on oxy/acetylene, very narrow and tubular and
>> well-formed, and I was told that I should be able to cut pretty far
>> away from the tip if I had good enough control to manage it.  The tip
>> has had some use now and not much cleaning but still maintains ~20" of
>> clean narrow cylinder of flame... now just recently I had taken to
>> running it slightly oxygen-rich, because of the increased intensity of
>> heat, which does seem to shorten the flame from its maximal length.
>> I might've been running the propane closer to 6 or 7psi in the
>> beginning, too, but have mostly been using this setup for heating (not
>> cutting) but the oxy lever is out of my way when the torch is clamped
>> next to the pilot.  I don't know what to suggest to you, since your
>> scenario sounds so similar, and hopefully I'm not overlooking any key
>> differences.  My initial level-setting procedure for the torch-body
>> needle valves seems identical to that of oxy/acetylene, I first bring
>> a fuel-only flame off the tip then add oxy.  Wind is a foe of either
>> =/
>> I have a feeling that propane mixtures need a little more "oomph" to
>> light, something about the fuel being so heavy and syrupy, but I can't
>> quite quantify that.
>>
>> Best of luck,
>>
>> Ben
>>
>> P.S. - my rig has cut before, and was reported by more experience
>> hands to be quite capable, and just fine as expected.
>>
>>
>> On Sun, Nov 8, 2009 at 7:16 PM, Paul N <crosspein at sbcglobal.net> wrote:
> 
> ______________________________________________________________
> 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
>