[WSS]

Here is a thread to post your Oxy/ Fuel cutting questions, ideas, problems and PHOTOS!

Let"s discuss codes, speed, gases, tips (consumables) or anything concerning oxy cutting.

And please don't be afraid to call "Dross" slag here. Oxy cutters will know what you are talking about!

Cheers!
WSS

[tinman13]

I have been looking for a way to ramp up the cutting oxygen, Something like a soft start valve, or........... ?

I have found Retro plasma makes a regulator assy. with "Ease on pierce rate control ". They describe it as "The rate that cutting oxygen pressure increases during the pierce is
set by the Pierce Rate Control knob".

I can't find much info on this type of system on the net.......... Anyone familiar with this type of system?

[jcc3inc]

Gentlemen:

I have attached (4) jpg's of a system and explanation. Hope it is of help to youall.

Regards,
Jack C.

PS: to print a decent sized page, click on desired page, right click on the result, then "print".
JCC

[millman52]

This is interesting. I often have trouble piercing material above 1" thick

[scrambled]

I am setting up a oxy / fuel cutter. I need all the help I can get.

Steve

[millman52]

Steve, have you made any more progress with your port 2 installation to get your system going?

[scrambled]

Millman, I talked to Tom, and he said that I have the wrong version of the IO card. So I need to get the correct drivers installed.

I just finished replacing the 7/8 drive stem pinions with 2 1/4 gears. Now the vibration is gone, I am going to work on the IO card.


What Post processor is everyone using for Sheetcam?


Steve

[tinman13]

Thank you JCC,
That is exactly what I have been looking for.
Steve

[WSS]

I wonder if this could be done with a small bore "oxy safe" air cylinder that has had the piston converted to a plunger and the rod changed to a 1/2-10 acme thread for adjustment? It would serve only one torch for the ramp up oxy. but might be doable. The ramp pierce is pretty handy to keep slag traveling in a rearward or away direction. The Hi PH could be done with a separate set of 3 way Asco type solenoids and a extra set of regulators. Once you found the right combination you could manifold the whole deal to pull from one (of each) bottle.

I converted the jpgs from jcc3inc's post to a pdf (Big thanks Jack!)

Here is a link:

http://files.me.com/izonltd/id43n2


WSS

[tinman13]

"air cylinder that has had the piston converted to a plunger and the rod changed to a 1/2-10 acme thread for adjustment? "

I'm afraid you lost me on that one!
Steve

[millman52]

Millman, I talked to Tom, and he said that I have the wrong version of the IO card. So I need to get the correct drivers installed.

I just finished replacing the 7/8 drive stem pinions with 2 1/4 gears. Now the vibration is gone, I am going to work on the IO card.


What Post processor is everyone using for Sheetcam?


Steve

Steve I had gone to the manuals on CandCNC's Yahoo site & done a bit of reading on installing the MP3000. Somewhere in there it mentioned the version of one of the cards needing to be current. It was yesterday evening when I was reading it & by now I can't remember the details.

Knowing your project has been a lengthy one just kind of assumed something slightly out of date might be your problem. I'm probably the worlds worst to buy something then let it lay for weeks or months before using it.

I started building an actuator type "Z" lifter & an new HT 1250 plasma nearly a year ago & still don't have that installed & am paying to have thin materials plasma cut. I can't really say I haven't had the time I just haven't made it happen.

Tom will get you through it. He has always had the answers I needed. Sometimes I can be shch a bonehead that it takes a week or 2 for what he is telling me to sink in.

I am using the Mach2 plasma.post for my oxy set up. (again I am running 2006 or so vintage MP1000 candcnc equipment)

[tinman13]

...... It just dawned on me what you are describing!

The air cylinder could be controlled with shop air and it wouldn't need to be oxygen clean.
I will have to experiment with force requirements to see how big of a cylinder it would take.

The beauty of this is I have most all the stuff laying around to build it with!
Thanks for the idea!

Steve

[WSS]

...... It just dawned on me what you are describing!

The air cylinder could be controlled with shop air and it wouldn't need to be oxygen clean.
I will have to experiment with force requirements to see how big of a cylinder it would take.

The beauty of this is I have most all the stuff laying around to build it with!
Thanks for the idea!

Steve

Steve,

Kind of, One side would have oxy running through it. The idea is to replace the dome in the drawing. This would be variable according to how far back the plunger (piston) is. 1/2-10 acme is nice because it is .100" per turn, easy to gauge. The more volume you have in the chamber the softer the start.

We are using a Thermco gas mixer here to mix argon and oxy. One of the problems we had when using liquid argon was the hard start and stop when the solenoid cycled. This caused the dewar (spelling?) to over pressure and vent. Even with the pressure builder off the shock would build pressure on its own.We ended up putting a 10 gallon tank in line to absorb the shock, a soft start/stop so to speak. The air cylinder would do the same and be adjustable. I am thinking a 2" bore bimba or rexroth type about 10-12 inches long would supply the needed drop for a soft start. I notice the longer the hoses are between my solenoid and torch valve the softer the flow starts. I had always believed you wanted to "snap" the pressure, but this looks like it might be worth a try.

If you notice in the drawing posted, the HP cut line is the smallest. This is due to the dome being able to supply the needed volume for a short time then switch to the larger, non stored supply of oxy flow.

Who wants to try it first?

WSS

[scrambled]

OK--

Time for some questions. Since I am wiring my single solenoid valve in, Is there that much of a difference using a soft start?

I have been trying to understand the piping schmatic, and to me it looks like I would need 9 solenoid valves. Is this correct?

Any other info on this that you have is greatly needed


Steve

[WSS]

Thinking about this, The goal is to pre-heat faster and keep the tip debri-free during and after pierce.

The ease on my be secondary to the hi-lo PH and a code controlled ramp pierce. I have done a version of hi-lo, and that was to use a rosebud to help the pre-heat along. The version shown in the drawing would be better of course, due to the smaller HAZ. The rosebud spread the heat around too much.

Another use for the hi-lo PH is to anneal areas on AR plate that will be machined later. You could go into that mode and circle the area or spiral out with great control.

Has anyone seen the ease on pierce in action or on video?

Steve,

You may be able to use 3 or 4 way solenoids to cut the number of solenoids down. Do you think you will try it?

I don't want to sound like a pest but make sure the solenoid you use for the oxy is oxy safe.

WSS

[scrambled]

WSS-

Thanks for the info. I am using the correct soleniods, that is the problem they are not cheap. That is why I am trying to decide if it will be worth it.

Steve

[jcc3inc]

Gentlemen:

Please note that the dome regulator is in fact a REGULATOR. The pressure on the slave side matches the dome pressure (which we set separately). You cannot use a leadscrew alone to move the diaphragm of the regulator, the leadscrew must drive against a *spring*
in order to vary the force. Thus output pressure is proportional to input pressure.

Scrambled; if you have questions, maybe I can help iin the understanding of them. Yes. the system is somewhat complicated, but industrial users who generate large quantities of cut parts must have these refinements.

Regards,
Jack C.

[millman52]

Aside from being great for piercing, I have found especially on chain cuts in 1" material of small/medium size parts around as little as 1# of preheat Ox & Acet. is plenty to maintain the cut. Using light heat during cut almost eliminates top edge rounding especially on thicker plate.

I don't have a system to change pressures automatically but I do regularly cut back the preheat gasses at the regulator(s) on lengthy or chain cuts.

[WSS]

WSS-

Thanks for the info. I am using the correct soleniods, that is the problem they are not cheap. That is why I am trying to decide if it will be worth it.

Steve

Steve,
I will write down the part #'s of the asco valves I have for oxy and post it later. I picked em up new from caltrol and were about $75 each if I remember right. They had them in stock in Vegas.

Jack,
The dome reg, How easily obtained are they? I thought from the drawing it was a reservoir only and that the needle was for pressure filling of the dome and was switched after dumping the oxy to be filled again offline. I do not have a full grasp on the concept. I am interested to see if anyone gives it a whirl.

WSS

[millman52]

Gentlemen:

Please note that the dome regulator is in fact a REGULATOR. The pressure on the slave side matches the dome pressure (which we set separately). You cannot use a leadscrew alone to move the diaphragm of the regulator, the leadscrew must drive against a *spring*
in order to vary the force. Thus output pressure is proportional to input pressure.

Regards,
Jack C.

If I understand this correctly, to ramp up the pressure it basically is an accumulator valve. Pressure hits a spring loaded chamber. as the chamber fills & compresses a spring the down stream pressure builds.

I know this is probably over simplified but is the basic premise. Correct?