I’m trying to decide what 2D CNC cutting solution best fits our needs. I’ve been researching different processes for a while and have read dozens of informative posts on this forum. Having performed as much research as I think I can on my own (and pestering Jim Colt with several questions via email
), I would like to ask a few specific questions about my application. Any advice you can offer will be greatly appreciated!
Our shop has been seriously considering an abrasive waterjet, but after factoring in all the support equipment, space becomes an issue and even a small 4’x4’ unit quickly approaches $200k by the time the necessary electrical upgrades (almost $30k) are performed in our facility. The search for the right cutting solution has forced us to re-evaluate and better understand our needs, which can be summarized below:
- 70%: 20 to 16 gauge aluminum and steel / min. hole size: 0.265”
- 20%: 0.125” to 0.1875” aluminum and steel / min. hole size: 0.265”
- 8%: 0.25” to 0.3125” aluminum and steel / min. hole size: 0.265”
- 2%: 0.375” to 0.5” aluminum and steel / min. hole size: 0.390”
Positional tolerance for most of our work is between 0.010” and 0.020” over 6” length; we cut a lot of holes (some of which approach a 1:1 ratio of diameter-to-material-thickness) and we would like keep the edge taper within a reasonable range. We’re not looking for laser quality parts, but we would like the ability to cut holes with tapers less than ~10% of the material thickness when the need exists. About 75% of the parts we make get bent in a brake and put into service and the rest get welded. The volume of parts we make is actually pretty low if that matters.
Based on my research and conversations with Jim Colt, I can likely accomplish my goal using the following three things:
- A rigid machine with quality feed drives and a controller capable of higher accelerations and cutting speeds (up to 400 ipm for thinner sheets)
- Very good THC that is capable of maintaining ~+/-0.005” height control (such as the Command THC or one of Koike’s offerings)
- A high definition plasma cutting system (like the HPR130XD)
My questions about going this route are as follows:
Since I am limited by floor space to a machine with a 4’x4’ cutting area, do any companies selling quality high definition plasma machines offer tables this small? (Unfortunately my research thus far indicates no.)
- Will I need a controller and CAM software that supports Hypertherm’s True Hole technology to achieve my goals, or will any modern controller achieve the tolerances I am after in the relatively thin materials I am trying to cut if I use a good high definition plasma machine?
- Will Fine Cut consumables work with the HPR series torches (or are they even necessary and/or compatible)?
- Will a larger power supply such as the HPR260XD provide lower quality cuts in thinner material (i.e. 20 gauge) compared to the HPR130XD, or is cut quality independent of machine size?
Since we will mainly be cutting thinner sheet on our machine, I’ve read many people have had good success cutting this type of material on (shop) air plasma systems by using the following technique:
- lower cutting speeds (< 150 ipm)
- lower power setting (to account for the lower cutting speeds)
- proper (often Fine Cut) consumables for better arc stability and narrower kerf width
This might be a dumb question, but can the two methods of producing low-dross, higher tolerance holes be combined? Specifically:
- Could an HPR130XD and Command THC be combined with a smaller 4’x4’ plasma table (since I don’t have room for anything larger) to achieve the goals I listed at the beginning of my post?
- Are any of the lower speed 4’x4’ plasma cutting tables/machines compatible with a high definition plasma cutting system if I accept the lower cutting speeds inherent in these machines (<150 ipm)? For instance, does anyone use an HPR series high definition plasma system on a PlasmaCAM, Torchmate or other entry-level plasma cutting machine? Or do the THCs and controllers found on these style machines nullify the potential benefits of the high definition plasma system?
- Does Hypertherm sell complete packages that can be installed on 4’x4’ off the shelf or custom cutting tables that include controllers, feed drives and CAM software? And if so, can anyone provide feedback on how difficult these systems are to retrofit?
- If I simply don’t have room for a 4’x8’ or 5’x10’ table and want some of the benefits of current high definition plasma process and I just out of luck ?
Thanks for any insight you can provide!
Mike