Oxy-Propane install on cnc table

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So about a year and a half ago I was trying to decide what kind of torch kit to put on my cnc table... see this old thread: http://weldingweb.com/vbb/showthread.php?p=383921. In the end I bit the bullet and bought an oxy-propane setup from my vendor (dynatorch). It arrived in the big box and it's been there ever since. I simply didn't have the time to set it up. A few weeks ago I decide that I needed to have this torch on the table and working before the new year. So I went out and bought a couple more oxygen bottles and a 100 lb propane bottle to get started.Today I finally have everything plumbed and and wired. I figured I'd post up some photos. The torch is a Victor MT310N. I'm still dialing everything in.Pic1: Routing of the two oxygen and propane lines. This took a long time.Pic2: I wrapped the last 5 feet with hose wrap.Pic3: Tanks and oxygen cutting solenoid valve. Pic4: Torch installed. Note that plasma torch can be moved out of position making it easy to switch.Pic5: First firing. (Yeah the torch was stored... I had a job in the middle of setup).Still trying to nail down the ideal settings. Attached Images
Reply:It appears the cutting solenoid valve isn't closing 100% allowing oxygen to leak past. I've cycled it many times trying to get it to seat. Still no joy. I suspect the valve is defective or has some particle lodged in it. Even de-energized anything over 3 psi is leaking to the torch. Any ideas what might cause the valve not to close?   Attached Images
Reply:Originally Posted by forhireAny ideas what might cause the valve not to close?
Reply:If you are calling the "Red Hat" the "arrow thingy", it does not indicate flow direction, If you slip the red hat off of the center pin, you can pull the coil off of the valve and take the valve apart.
Reply:Originally Posted by Fred sIf you are calling the "Red Hat" the "arrow thingy", it does not indicate flow direction, If you slip the red hat off of the center pin, you can pull the coil off of the valve and take the valve apart.
Reply:Made a quick test cut. Material is 1" A36. Pierce was ugly and the cut was just ok. Not sure if I'm too slow or two fast. Preheat flame looks good and sharp but I'm getting a pop now an again. Maybe someone with more experience can give me some pointers. Torch is Victor MT-310N.These are the settings I tried:Nozzle #1 GPNPreheat LPG 10 psi, Oxy 20 psi Cutting oxygen 85 psi17 ipmstandoff about 3/8"Manual recommendations:#1 tipCutting O2 85/95Pre-Heat O2 10-50 psiPreHeat LPG 8+ psiSpeed IPM 17/24Kerf width 0.07I still need to do some more playing with the software. Right now I'm heating, piercing, and cutting at the same height and it would reason that each would have a set point. Here are some photos.Pic1: Front side. The scrap had three 3/8" holes in it before starting.Pic2: Back side.Pic3: Used the hammer to free the parts.Pic4: Compare this cut with the plasma. I have some room for improvement.  Attached Images
Reply:It's hard to say much from just looking at it. The sound it makes as it's cutting is the real tell tale for me. Anyway I don't see signs of going to fast on the finished cut so I'd say you're probably going to slow. There's a sweet spot when flame cutting where the slag is blown off. If you'll watch my video Cutting 1" plate with 1 1/2" tip you can hear the sound I'm talking about. It's in post number 8 herehttp://weldingweb.com/vbb/showthread.php?t=63275  You can try varying the oxygen pressure or cut speed to get this sound. More pressure usually means faster cut. But each tip is different even in the same size brand and sometimes you just have to play with it to find the magic setting. In my video's Adjusting a cutting torch and other tricks or for higher definition of the same video Adjusting a cutting torch and other tips I show what to look for in a good setting for a tip. However when pressures go up higher that doesn't always work and I've not worked with propane in a long time so I can't say for certain what to look for. But these might help get you started in the right direction and hopefully someone with more experience with CNC and propane will chime in to help.   One thing I've done in the past while running track and pattern torches is vary the speed while making the cut. For the longest time I would stop short and slow down when the cut went to sputtering like it did above thinking that I was going to fast. But once I learned that was the sweet spot I started tuning for that. Also since you've got separate regulators for the preheat and cutting oxygen you can try varying the oxygen pressure during the cut to try to fine tune. I did that on our pattern torch once I added the second regulator like you have. That was where I really learned about tuning the torch for the best cut. I couldn't adjust the oxygen pressure on our track torch since it only had one regulator and it would affect the preheat if I did.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:Thanks Wayne. Looking at the photos again I would say I was slow also. The top is a little rounded and the bottom has blob slag. Even a few IPM can make a huge difference. Honestly I was glad I got a fairly good cut the first time.I found this thread:http://www.practicalmachinist.com/vb...utting-196905/The MT310 is a good torch. Use two wrenches to tighten the tip nut and the popping should stop (a 1" and a 1-1/8"). On 1" a-36, 16 to 19 inches a minute is common with a MTHN-1 @85psi cut and 30psi preheat oxy and 5psi on the LP.
Reply:You're welcome. Hopefully some of it will help.   I don't like running a tip to close to the work. Yes you might get a slightly better cut but you're more likely to get the tip dirty. I prefer a little distance between the cones on a acetylene tip and the work. I believe that with propane you even want more distance. It does make a difference how good the tip is. I was cutting the web on a 5" x 5" I beam today and had to hold a 1 1/2" hold off distance in order to get my cut close enough to the side. Since I started that way I finished the cut that way. I could do it because I was using my good tip that maintains the tight cutting jet for a long distance from the tip. But many/most tips even new won't maintain that nice tight jet.   That's where playing with the oxygen pressure helps. You can play with it till you get the longest jet out of the tip and try it that way. The problem there is that sometimes that's to low a pressure for thick plate and/or high speed cutting.   Oxy fuel cutting is as much art as it is science in many ways. You have to get a feel for it to be really good. The problem is that getting that feel takes time. Nothing is the same every time and learning what's needed to correct for the problem can take some experimenting to figure out. Especially when you first start it can be extremely frustrating trying to figure out what needs changed. There's just to many variables. That's the reason I went with video with my tutorials. There's to many little things that can change the cut like speed and oxygen pressure, hold off, size of preheat, condition of material, the phase of the moon, etc.   Figuring out which variable needs changed takes a little experience. Nothing beats practice even when it's computer controlled. Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm