Short life of consumables

[Gec]

Hi, on my machine nozzle lasts couple meters of cutting, and few pierces
I have Powermax 1250, THC is Burny CHC-6, all settings is according to Hypertherm manual. I read all Jim's posts on that theme. I found that problem can be in air moisture, so I bought Boge refrigerating air dryer with 3 microns prefilter, is it this good enough, or I must put after dryer 0,01 microns filter?
Second....my THC works fine, but I don't have options to put piercing height to one value and cutting height on different (maybe is that problem?). Consumables is original Hypertherm, cutting height is 1,5mm, I cut with shielded cup, cutting quality is very good at the beginning but after few cuts as consumables are in worse conditions quality of cuts is bad. I don' had installed yet air dryer. Sorry on bad english.

[cam1]

Hang in there, Jim will be along soon....

regards

[Big John T]

From every post Jim has made pierce height is critical to consumable life...

1.5 to 2 times cutting height...

Jim did I pass the memory test?

John

[eldonb46]

To Gec,

I have been using a PlasmaCam with a HyperTherm 1250 for about three years, and yes "everything" affects cut performance and consumable life. I use 80A Drag-able tips for thick stuff and Fine tips for everything else.

I use a refrigerator dryer and it make a BIG difference for both issues. I think moisture cools the side of the plasma which diverts the plasma jet to one side which messes up the cut. Also, I think moisture some how erodes the side of the orifice which also changes the pattern of the plasma.

I only use the standard HyperTherm mounted filter, I think is is 5 micron.

Air pressure and current setting (amps) also cut performance and consumable life. I try to use as little current as possible to make the cut and try to avoid too much air pressure that the plasma is wasted below the cut part (i.e., blowing the plasma away from the cutting area). You can tell when everything is setup "just right" by the amount of smoke that is being created - the MORE smoke, the better the cut, and with less slag. While making a long practice cut, change the current and air pressure (as necessary) to produce the most smoke. Also you should note the distinctive cutting sound, from then on, you will know when everything is "right just" by listening. Your parts will require very little cleanup!

Splash back from piecing is the next biggest thing that damages the cutting tip, I avoid piecing for new outlines by always start from a previous cut or just off the edge. I only piece for internal cuts (there is no way to avoid it, short of drilling holes, which I have done on 3/4 inch material ).

Next, running over (of hitting the tip on) previous cut slag will damage the tip - clear off previous slag chips where you can. Any electrical connection from the cutting tip to the cut plate via a slag chip WILL always damage the cutting tip! For fine tip cutting, I use a discarded and modified Drag-tip-shield that is cut down to slightly longer than the Fine tip, which helps avoid hitting the plate and slag chips. It also helps blow away small slag chips during the cutting process.

You can see my setup and examples at: http://www.MR-FAB.com , then goto the Gallery.


I hope this helps,
Eldonb46

[donnelson]

i have a power max also and the part inside the unit that controls the on time like for cutting expanded metal was stuck on all the time which shortened the life span of the cup part you can also look at the side of the electrode if you see black like finish on the electrode it is usually from moisture you can test the control part by measuring from the nozzle to ground with the powermax turned off it should not have continuity to ground that is what the rep from hypertherm said give them a call they helped me out kindly

[Gec]

Originally Posted by eldonb46 You can see my setup and examples at: http://www.MR-FAB.com , then goto the Gallery. I hope this helps, Eldonb46

Thanks, guys....Eldon, that's nice tips and tricks for settings plasma cutter, thank you! I'm totally beginner at plasma cutting so this kind of advices worth it a lot. I looked at your web site, there is a lot of nice work. Can you tell me did you decreased air pressure lower than 5 bars on Fine tips, and do you have on your machine possibility to pierce on one hight and cut on lower hight, or is this same value?
To Donnelson....I'll try to measure resistance between ground and nozzle, thank you.

[eldonb46]

Originally Posted by Gec . . . Eldon . . . . Can you tell me did you decreased air pressure lower than 5 bars on Fine tips, and do you have on your machine possibility to pierce on one hight and cut on lower hight, or is this same value?

Gec.

I use the published numbers for both presure and current (amps) as a guide to start, with piercing at .15 inch and cutting at about .1 inch depending on the thickness of the material. Thicker material (i.e., > 3/8 inch) requires longer pierce time (maybe > 2 seconds) and also more hight to allow the higher volume of backsplach to escape in the cooling air around the tip. The less backsplach hitting the tip - the longer the tip will last.

Also, I use the HyperTherm "machine air diverter - P/N 120925" inside of the handle (note; it has larger diversion holes) to allow more cooling and wash air than the hand wand diverter, which documentation suggests should be used. This allows for a more air presure setting without blowing the plasma below the material cutting area (see previous post).

Again, watch for the highest volume of "smoke" and the distintive "thissss" sound while making adjustments to preasure and current (it is almost magic when you get it right). With the higher volume of smoke there will also be a reduced volume of sparks spraying out below the cut, the smoke is realy vaperized metal (which will land on everything around). Note: the smoke is probably VERY bad for you - you should vent it out and away!

BTW, it took me a lot of trial cuts to learn how to do things just right, I have not see anything in the documentation that suggests how to make things a little better with such small changes.

Have fun,
Eldon

[Gec]

I installed refrigerating air dryer, it seems that moisture was main problem, now I got excellent quality at 10 mm. steel plate without dross, today I made first cut with Finecut tips on 2 mm steel without dross too. It cuts like laser...wow that's quality, Hypertherm rules Next week I'm planning to start building water table. Thanx everybody.
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[ziptie007]

Off subject a little but where did you get your air dryer from and how much. Thanx

[Gec]

Originally Posted by ziptie007 Off subject a little but where did you get your air dryer from and how much. Thanx

I bought it here in Croatia (Europe), it costs about 1000 Euros with prefilter, it is big capacity, about 600 l/min.

[ziptie007]

thanx for the reply with the info.