I am still trying to choose cutter - post flow question

I have seen some cutters have ajustable post flow and others are fixed at something like 15 seconds… - how does this affect usage. when cnc cutting?

The purpose of Post Flow is to cool the torch. The longer the cut the higher the amperage along with cut speed the more heat you would like to dissipate.

I think I read here someone had a machine that would not re-fire will in post flow causing him to pause after each cut. That would slow things down significantly adding to the project time.

I read it somewhere too - i believe it was a longevity unit - which is what i was looking at - So , this is why i ask. I t also will consume much more air during operation if it behaves in such a manner. So, that is why I pose this question, You think its just some units behaving like this?

But I believe, normal behavior should be to beable to refire the torch before the post flow has completed.

I have never really noticed if my post flow is fixed duration or variable depending on the current duty cycle. I have the RW45 and it will re-light the torch while in post flow.

I don’t recall what unit the operator had mentioning the not re-lighting during post flow. He is the only one I heard it from.

I don’t have issues with my RW per say but if money was no object I would get a Hypertherm after that if I had it to do over I would have purchased the Everlast 60S CNC

1 Like

Yeah, I would do the hypertherm if money was no object. The thing i am concerned about with the razorweld ( at the top of my budget) is its high CFM ( though may be some benefit for blowing clean cuts ) I would have to reoutfit my compressor ( which negates budget ) I am looking at the everlast ( seems popular here ) and i have looked at the longevity units… ( this was mentioned with post flow issues here in the forum ) . And I am finally considering a primeweld cut60… which i know nothing about as far as high frequency interferance - it may be in the realm of the alpha or the lotos - that is what i am concerned - i wish i knew if someone here was using one…

I run mine on a Home Depot compressor that’s not quite up to spec. The tank holds enough to help dampen the need for the compressor itself to be able to deliver full air. With my projects I’ve not seen it cause a problem as it cycles - it certainly doesn’t run non-stop. If I were a commercial operation running jobs all day I’d be more concerned with a less than spec compressor.

I guess i could always pause it if need- but i am was planning on using fine cut tips mostly because i will usually be cutting 16 gauge or less , so i guess the consumption would be less than 6 cfm with that.

15 to 20 seconds post flow is a standard built into most plasma cutters. As said the longer the cut at high amp on thick metal would need more post flow to cool the torch, but post flow also cools the consumables and this makes them last longer.

We put an adjustable post flow on the Primeweld cut 60 that can be set up to 60 seconds just for this purposes. The cooler you keep the consumables the better the cuts and the longer they last.