Cutting Expanded Sheet Metal

[GWD]

The PP50 has a pilot arc but it must not be working based on your description. I notice that nobody from Everlast support has chimed in to this thread yet so maybe one of them can come up with an answer.

Does your PP50 establish a pilot arc when the torch is started in mid-air? (Not recommended except for a test.) That should tell you if the pilot arc is working.

I have a PP70 that zips through expanded metal without a problem because the pilot arc stays lit in the gaps. The pilot arc does increase consumable wear from what I understand but since I don't cut NEARLY what you do I can't tell much difference in wear.

[fdcmiami]

it seems you would go broke buying consumables for that much cutting and it still would be slow. maybe if you locked a straight edge in a position that would allow you to move down the center of the v's a little more quickly that would work. there are many ways to deal with this you'll have to find the most cost effective on for you.

[xtreme cartz]

it seems you would go broke buying consumables for that much cutting and it still would be slow. maybe if you locked a straight edge in a position that would allow you to move down the center of the v's a little more quickly that would work. there are many ways to deal with this you'll have to find the most cost effective on for you.

Well that is a good point. Even if the plasma was cost effective for this application, attaining a tight tolerance without burning out the vee is another story, plus the slag would take much longer to clean up than the burr from a cutoff wheel.

Do you honestly think I should just by more dust masks and a bulk load of cutting wheels and quit whining? Lol

[fdcmiami]

as i have said, i have cut a lot of it. what you want is a common request and it is commonly done procedure but you need some background in shear operation to visualize the process.

you'll get there....or go broke buying cutoff wheels.

[xtreme cartz]

60 psi. Small HF 2 1/2 gallon air compressor dedicated to the plasma cutter. I can hold the trigger and it will rearc after a second, but it stumbles before the next rearc by making half of an arc, and then it gets going again if you see what I'm saying. If I move slowly it does better about not half arcing first. Best I can describe it is as a stumble before each cut through the vee,.

[Rodsmachineshop]

Small HF 2 1/2 gallon air compressor that wont cut it for a plasma cutter not big enough compressor cfm

[Rambozo]

Small HF 2 1/2 gallon air compressor dedicated to the plasma cutter.

The PP50 spec calls for 3.5cfm, it's doubtful that small compressor can keep up with the demand.

[performance]

That spec is for minimum cutting as well @ 90 psi, not 40. For best results, it will need 5 or better.

I can't tell you how many people try the 2.5 pancakes and are MISERABLY disappointed with the results.

[CGCINC]

I recently purchased the PP50 and just cut some expanded metal the other day...Buzzed right through like butter!
My compressor is a 33gallon and rated at 5.3cfm

[xtreme cartz]

Second question while we're at it, what is better for the tip to be dragged or held slightly off the metal? As much exp metal cutting, I do equal or more 4x8 16ga sheet metal cutting and until I build a CNC I do it all by hand with the plasma or circular saw. I want to build cutting jigs from either 3/16" or 3/8" flat bar that are the same shape as the parts I'm cutting. This way I can just set it on the metal and trace it with the torch to make a perfect part cutout instead of all the layout time it takes with a template, marker and straight edge.

3/16" flat bar puts the tip right on the metal.
3/8" flat bar allows the tip to be suspended nicely in the air, leaving about 1/16" gap between the tip and the metal being cut

[Rambozo]

Second question while we're at it, what is better for the tip to be dragged or held slightly off the metal? As much exp metal cutting, I do equal or more 4x8 16ga sheet metal cutting and until I build a CNC I do it all by hand with the plasma or circular saw. I want to build cutting jigs from either 3/16" or 3/8" flat bar that are the same shape as the parts I'm cutting. This way I can just set it on the metal and trace it with the torch to make a perfect part cutout instead of all the layout time it takes with a template, marker and straight edge.

3/16" flat bar puts the tip right on the metal.
3/8" flat bar allows the tip to be suspended nicely in the air, leaving about 1/16" gap between the tip and the metal being cut

Some tips are meant to be dragged while others require a standoff. The problem with a template is that unless there is an insulator on your torch tip, you can't let the nozzle have an electrical connection to your work. So your template would need top be made of non conductive material, or your torch tip. Either way, the lifespan would be an issue. You can do something like Rod did and build a tracer. It's sorta like a manually operated CNC, with you playing the part of the computer. Another thing is to change the size of the pattern so that you can space the torch away from it to increase the life. This limits the kind of pattern, too as you won't be able to have tight curves. It all depends on just what you need to cut. I've always cut expanded metal with a shear, but I remember getting cut from some of the wicked points that could be left depending on the size piece.

If your cutting fast enough, I imagine a piece of 1/4 hardboard or plywood would make an adequate template you could probably increase the life with a flame retardant coating. It'a all about volume, do you need to make 100 parts or 100,000? Also the skill of the operator comes into play. Do you buy a high tech machine to be run by a grunt, or have a real craftsman who can get good results even from basic tools?

[xtreme cartz]

Here's a go at my video. If I move slow enough like this it doesnt stumble. Everything looks to be working right.
http://www.youtube.com/watch?v=9n32A...ature=youtu.be

[Rambozo]

Here's a go at my video. If I move slow enough like this it doesnt stumble. Everything looks to be working right.
http://www.youtube.com/watch?v=9n32A...ature=youtu.be

And what you are expecting is this...

[xtreme cartz]

And what you are expecting is this...

Yes that is awesome! I at least was hoping it to be as fast as a cut off wheel . I wonder how much the consumable life is reduced using it like that?

[Rambozo]

It appears that Hypertherm also has that feature but they call it grate cutting mode instead of auto refire. Both say it does reduce consumable life, but neither say how much. It just causes the machine to switch back to pilot arc mode when a void is encountered. It sounds like not that hard of a feature to add to a machine. Just a change in the way the transfer works. Maybe it is something you can modify? There are some threads about it on CNCzone.

[xtreme cartz]

The PP50 has a pilot arc but it must not be working based on your description. I notice that nobody from Everlast support has chimed in to this thread yet so maybe one of them can come up with an answer.

Does your PP50 establish a pilot arc when the torch is started in mid-air? (Not recommended except for a test.) That should tell you if the pilot arc is working.

I have a PP70 that zips through expanded metal without a problem because the pilot arc stays lit in the gaps. The pilot arc does increase consumable wear from what I understand but since I don't cut NEARLY what you do I can't tell much difference in wear.

Yes my pilot arc seems to be working. I can try to post a video of it going through the exp metal. I would love to see a video of yours cutting.

[xtreme cartz]

I can visualize the process. I can also hear what my local metal distributor said and that is what has been in my mind all this time. What size shear? I'll buy one.

[performance]

The pilot arc should relight without reengergizing the arc with the trigger. There is a noticeable difference in the arc though. IF the arc is going out completely there is something wrong. You may try adjusting your air flow/pressure though. What size air compressor are you using? What air pressure are you trying to cut at?

[xtreme cartz]

Those saws do work pretty good for cutting flat bar and plate. We're a small company about 5 yrs old started from the ground up, have been manufacturing for about 2 yrs and are growing very quickly recently due to the attention we pay to producing high quality products and customer service. Being such a young company we are faced with having to step up our facilities to match increasing demand. Our profit margins are tight. In the past we had some sheets cut by other companies, but with overseas competition we need to keep all of our manufacturing in house. I hope to build a CNC plasma table soon and increase consistancy on our products that have 16ga sheet metal. Most of the specialty equipment we use I have built myself including our electric hydraulic tube bending machine.

The angle grinder believe it or not works for exp metal, but I would like to find a better way.