Lightweight hoses: OK for oxy-act cutting?

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Hey, finally bought my first oxy-act rig, a smith AW1A with smith medium duty regs. Just like makoman1860 (aaron) suggests. But... can you use the smith kevlar hose or Kent's tinmantech.com hose when you cut? Can these hoses be attached directly to the regs, or should they be used as a leader hose? I know you can use those hoses for welding, btw.The LWS told me the smith kevlar hose was only for brazing (contradicted on this forum) so they're no help, and I can't seem to rustle up a response from Kent's shop (1 email and 1 phone call).I'm being a little cautious because I don't want to blow up if the hoses are too fragile for cutting (don't want to find out the hard way).Last edited by carbon; 11-30-2010 at 04:19 PM.Reason: reason for question
Reply:I doubt they are too delicate for cutting, but why not ask the maker who will know much more than the vendor:http://www.smithequipment.com/contactus.html
Reply:Alright, sent a question to Smith and am going to call tinmantech yet again.
Reply:Ok, here's the reply from Smith:"This hose is too small for the flow requirements of the cutting tips that can be used in the cutting attachment. Also the flame that is produced with these larger tips make it much easier to damage this hose." Also, "...you can using the welding or brazing tips with it."Still gotta call tinman.
Reply:That warning makes sense from a "general user" (drooling lawsuit-happy POS) standpoint. If I drag my cutting torch flame across my hose I deserve what I get and I won't sue anyone for my stupidity. That's up there with "do not use arc gouger while naked" and "do not use circular saw in your lap" warnings. As for any flow limits, if it were mine I'd install a cutting tip and test for starvation. It would maintain flow sufficient to cut, or it wouldn't.It works, or it doesn't. Keep in mind that the difference between "cutting tips most people use" and the MAXIMUM tip an attachment or torch will take is considerable. Also, within reason you could increase oxygen regulator output pressure to compensate for smaller line diameter. It works, or it doesn't.Safe acetylene pressure limits should NEVER be exceeded.What number size tip(s) do you actually want to use? What thickness metal do you want to cut?Last edited by farmall; 12-03-2010 at 04:48 PM.
Reply:Ok, so I talked to tinman, and they said the max psi the hose should be used at is 40psi. They said it was ok to use for cutting, but according to the Smith tip chart, I could only use the MC12-00 tip (the smallest one) with my AC309 cutting attachment. They said to watch for the hose ballooning, and to stop if that happens.Ballooning sounds like a possible reason the Smith people don't want us to use their kevlar hoses for cutting...my guess.Farmall, I have tips 00, 0, 1 and 3. I'd cut metal up to about a 1/2".
Reply:Originally Posted by carbonOk, so I talked to tinman, and they said the max psi the hose should be used at is 40psi. They said it was ok to use for cutting, but according to the Smith tip chart, I could only use the MC12-00 tip (the smallest one) with my AC309 cutting attachment. They said to watch for the hose ballooning, and to stop if that happens.Ballooning sounds like a possible reason the Smith people don't want us to use their kevlar hoses for cutting...my guess.Farmall, I have tips 00, 0, 1 and 3. I'd cut metal up to about a 1/2".
Reply:You won't need any bigger than a #1 tip, and 40 psi is sufficient for that thickness. I cut many plate and pipe test coupons with #1 tips. Try it out since you now know recommended pressure for the hose. Worst case, ya get to use larger hose for thicker work and it takes a couple of minutes to swap.Where you want neater long cuts on 3/8" and greater stock, make a (slow) preheat pass (don't depress the cutting oxygen lever) to warm up the metal. The cleaner you cut, the less you have to grind.