Anyone have one of those PCNC machines?.......

bhyde said:
Interesting looking blade Nathan...I'm curious...Were you surfacing that blade? The code in the pic seems to support this.


Bill
Click to expand...


Yes, I was, by surface isolines.

To answer your question, Bruce Boone, the blade isn't tiled, and there's no taper to the end mill. That approach would work on a straight edge, but it wouldn't work right around the belly. I created the blade shape and grind and edge thickness I wanted in CAD first. It is a 10" hollow "grind", so it has a 5" radius which remains perpendicular to the edge as it goes around the belly. I created the blade shape with a single continuous NURBS type spline, so there are no C1 surface discontinuities (I'll give a better explanation what this means if anyone wants to know) and specified the tool path to follow the surface iso lines so the cuts are made as a smooth motion from end to end. You can kind of get the idea on the second pict. That machining strategy results in the smoothest most natural finish, which means no blending and less bench time sanding. It also requires three axis simultaneous motion along a spline shape, which most any CNC today can handle beautifully. But it is a good example of something that couldn't be programmed manually, so requires CAM.

I could have changed the design to make it something that could be programmed manually, but for me that would be the tail wagging the dog. I'm not saying there is anything wrong with that approach. But this is what it takes for me to get what I want, so this is what I mean when I said it takes CAM to fully utilize CNC. I guess I should have said it takes CAM for me to fully utilize CNC.:)
 
Nathan............you are right on the pinacle of what we're talking about here. Wayyyyyyyyy beyond where I was at when leaving the shop.

I don't know what they're paying you where you work but I'll tell you right now........ it aint enough :thumbup: :thumbup: ;)
 
Nathan, keep it coming. I love reading and learning this stuff. On my CNC, I am running an Ah Ah contoller with Artisan software. Ah Ah went under last year and I have met some of the guys who use their stuff and have a fair amount of parts. I am going to spend $1,000.00 and my controller will be like new and I'll have enough spare parts to last a while. It is better than spending 10K to upgrade my machine with a new system.
I'll also be using Mach 3 software. I will be able to use a windows based machine instead of the 486 dos based unit.

(Hey David, nice chatting with you too. We have a lot in common. I'll call you soon.)
 
Thanks for the kind words, David. :thumbup:

Nathan - no offense intended...just seemed overwhelming and very daunting...and I'm no newbie to CAD...



If what you guys say is true...I'm definitely going to pursue this.


but now I'm curious abou the haas....any more opinions?
 
I looked at a Haas Office Mill when I got my Tormach. I wasn't that impressed with it. You need to add this and that and the other to bring it up to snuff, and it ended up being around 50K for the stuff I needed. It's also heavy enough to need rigging, which is now an issue that my pool decking is in. It is a resellable machine, I'll give them that.
 
30-40 K is for a base machine. Add 10K for a tool changer and another 5-10K for tool holders, extra memory, high speed spindle and other special features that do not come standard.
 
Daniel Koster said:
Thanks for the kind words, David. :thumbup:

Nathan - no offense intended...just seemed overwhelming and very daunting...and I'm no newbie to CAD...



If what you guys say is true...I'm definitely going to pursue this.


but now I'm curious abou the haas....any more opinions?
Click to expand...


No offence taken. I think it is human nature, when one has spent a lot of time or a lot of money pursuing something that, the approach that "I" took is right, and thus the approach that "they" took must be wrong. I was coming across as if this is "the only way", when in fact, it is just the only way for me... To each their own.

The Haas is a very very very outstanding value, and thus builds more machine tools than any other builder. They're number 1. They're inexpensive and, for many classes of work, get the job done. They're the work horse of the American machine shop. That said, they're pretty cheep, disposable machines, in the same league as Fadal and Hurco, but a little easier to use and maintain. They're not a Mori Seiki or an Okuma. I think the Haas is just right for a production knifemaker like Chris Reeves etc.

The Haas office mill does not strike me as a good value. I have some hesitation with their toolroom mill too. The travel to weight ratio is very light and the positioning accuracy is half that of their other machines. With that said, it will most likely outperform any other machine mentioned in this thread and it is probably overkill for most knifemakers. They start in the mid 20's.

My favorite Haas for a knifemaker is the Haas MiniMill. I selected one for the prototyping area in the engineering office where I work and I use it all the time. It weighs about 3,000 lbs, it has 12 by 16 travels, a 10 tool ATC and an enclosure. You have to add flood coolant as an option (and you should) but other than that, you're good to go for around the mid 30's. Something that is remarkable to me is, when you machine a circle with it and inspect the finish, there is no tell tale mark in the four quadrants where the screws reversed direction. When I put a coaxial indicator on a boss or hole milled by the Haas, I find it to be as round as a part turned on our lathe. That's good stuff. Machine tools have come a long way. One of the mills in my shop was 55 grand in the early 90's. The 35 grand Haas outperforms it in every way.

But, for a knifemaker wanting to automate a tedious operation, or create something that requires CNC, I think that mill Bruce Bump picked out is probably adequate. And imagine how many knives you'd have to sell to pay for a Hass (me, about 3500; Bruce, a dozen...*feh*).

I would be leery of buying a used Haas unless you know the history. These mills are considered "through away" in industry. People run them at 100% rapids and machine at spindle red line 20 hours a day, 7 days a week and earn 100K on a 35K investment and wear them slap out, then sell them on ebay.

My .02 on Haas
 
I fully agree Nathan. I think their full machining centers are a lot better value than the office mill. I've used them before, and they do go day in and day out without ever a hiccup. I guess that's why I was so surprised at the office mill, and all the adding it took to get it to what I needed. I now have a situation where I need a smaller machine to be able to fit in the space and through a double door, so that was a huge factor in my decision for Tormach over something like a full Haas machine. I also needed a rotary axis and coolant. I gave up the automatic toolchange capability by going to the Tormach, but the stuff I needed it for used the same small cutters without a lot of changing around. If I had unlimited space, electrical service, and a way to place it, my decision may have very well been different.
 
With all this talk of mills ...

This is the new 'small' mill we'll be running scales on shortly.

Hardinge/Bridgeport XV 710 being delivered last week.:thumbup:
 

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JCaswell said:
With all this talk of mills ...

This is the new 'small' mill we'll be running scales on shortly.

Hardinge/Bridgeport XV 710 being delivered last week.:thumbup:
Click to expand...


That appears to be a new machining center. Very nice lucky dog....
 
I wouldn't get the Haas Office Mill for knifemaking... actually, I din't get it. The TM-1 has some drawbacks – mainly you need to make some splashguards for it – but you can buy the machine and upgrade to a toolchanger later. As well as a 4th axis. The accuracy of the machine is more than you'll ever need, don't worry about that.

Any CNC machine will require a substantial investment in tooling and gizmos as well as a major investment in learning time.

In the end, the TM-1 is one of the cheapest machines (earnings to cost) I own and without it I would have had to close my shop and go out of business last year.

Go over to Haas' website. They have a build your own machine feature on their website and you can see exactly what the machines cost.

The Mini Mills or a VF1 are a whole nother leagure of fun but also substantially more dough. I don't see how a one man shop could effectively operate a machining center and not loos money big time.

I still make individual knives rather than "runs" or small production batches.
 
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