chris.sallis
Plastic
- Joined
- Aug 6, 2020
Sorry for the long post ahead. I’m looking for purchasing advice and want to provide a background first. I’m a research engineer at The University of Alabama in Huntsville. Most of my machining background is CNC routers, 4-axis hot wire CNC (designed and built myself), and manual knee mills. Our research center has a machine shop with all the standard equipment: manual knee mills, lathes, saws, etc. We also have a 94 Lagun KMC 250 that hasn’t run in over 10 years and a 2001 Victor 1654 DCM that lost is parameters and barely works as a NC machine. We have traditionally used on-call machinist for our work, but they have recently left. I plan to take over all the CNC machining operations if we get to replace our machines with something functional. I’m wanting to make a sales pitch to our center director to remove both of those machines and replace it with something functional. I started down the Fadal path based on what I’ve learned due to my own desire to eventually put a 4020 in my garage one day.
The only machining work we do is prototype work or very low volume production to support our research contracts. We will never do high volume machining and don’t have the desire to do that. Cycle time is not a big concern because of the low volume and one-off operations and even a slow cycle time would be faster than doing it manually. Most of the parts we make are plate type parts and brackets. 90% of the parts we make are aluminum, the rest being steel or plastics. My area of research is unmanned aircraft and I want the ability to do lots of 3D machining to make aluminum molds for composite parts.
The machine shop probably gets used on average 1 day a week averaged over the year, therefore we won’t be putting a lot of hours on the machine annually. The appeal of Fadals is the vast majority of information available that makes the learning curve not as steep. Additionally, the large availability of parts and the low cost of parts compared to other machines makes it easier to keep the machines serviced. This is a big factor because we haven’t paid for a service tech ever, so I will also assume that role. Calling out a service tech would exceed the cost of any one of our machines, which is why they have largely degraded over the last 20 years.
For the most part, the working volume of a standard knee mill allows us to produce 80% of the parts we make, which is why I’m leaning toward a 4020 over a 3016. Although a 6030 would be even nice, but I’ve heard there are no additional supports for the longer table on the 6030 and as a result causes problems, not to mention the higher base price. Generally speaking, +/- 0.005” tolerance would suffice for the majority of our operations. Therefore, some wear and backlash are acceptable.
So here’s my wish list: must be a HT model with at least 10k spindle, must have rigid tapping, carousel type ATC, already setup for 4th axis would be nice, must be a model with AC servos, needs to have 88HS control because we will be doing the Calmotion 527F retrofit. I prefer a model with linear rails on all 3 axes because it’s easier to service myself than the turcite on box ways. I understand this affects rigidity when taking big bites out of steel, but I can afford to not push so hard due to our low volume operations. We will exclusively be using Fusion 360 for CAM. Based on that information:
1) What years and model (dash number type) should I be looking for, or am I looking for a unicorn?
2) Were linear rail and HT model combinations even an option? If not, can linear rail models run the 10k spindle?
3) What is considered high and low hours respectively on these years 95-2001?
4) I am budgeting for replacing the spindle, at least 1 ball screw, axis thrust bearings, and possibly new spindle vector drive (Glentek amp from Calmotion). What other expensive maintenance parts should I consider?
5) We get an educational discount from Calmotion, fyi. I don’t know that I’m at liberty to discuss, but it helps significantly.
6) I realize machine prices varies by location and condition, but was is a reasonable price for a well taken care of 4020 that may need some minor maintenance, excluding rigging?
7) If I end up with a box way machine, what’s a reasonable cost to have the turcite replaced?
8) I realize rigging prices significantly vary across the country. What would be considered low vs high cost for rigging at both ends (pickup and delivery).
9) Is it reasonable to think that a $20k budget, excluding rigging, would get a machine and bring the maintenance up to spec is achievable?
I appreciate any and all feedback. If you happen to know of a unicorn like this for sale, feel free to put me in contact.
The only machining work we do is prototype work or very low volume production to support our research contracts. We will never do high volume machining and don’t have the desire to do that. Cycle time is not a big concern because of the low volume and one-off operations and even a slow cycle time would be faster than doing it manually. Most of the parts we make are plate type parts and brackets. 90% of the parts we make are aluminum, the rest being steel or plastics. My area of research is unmanned aircraft and I want the ability to do lots of 3D machining to make aluminum molds for composite parts.
The machine shop probably gets used on average 1 day a week averaged over the year, therefore we won’t be putting a lot of hours on the machine annually. The appeal of Fadals is the vast majority of information available that makes the learning curve not as steep. Additionally, the large availability of parts and the low cost of parts compared to other machines makes it easier to keep the machines serviced. This is a big factor because we haven’t paid for a service tech ever, so I will also assume that role. Calling out a service tech would exceed the cost of any one of our machines, which is why they have largely degraded over the last 20 years.
For the most part, the working volume of a standard knee mill allows us to produce 80% of the parts we make, which is why I’m leaning toward a 4020 over a 3016. Although a 6030 would be even nice, but I’ve heard there are no additional supports for the longer table on the 6030 and as a result causes problems, not to mention the higher base price. Generally speaking, +/- 0.005” tolerance would suffice for the majority of our operations. Therefore, some wear and backlash are acceptable.
So here’s my wish list: must be a HT model with at least 10k spindle, must have rigid tapping, carousel type ATC, already setup for 4th axis would be nice, must be a model with AC servos, needs to have 88HS control because we will be doing the Calmotion 527F retrofit. I prefer a model with linear rails on all 3 axes because it’s easier to service myself than the turcite on box ways. I understand this affects rigidity when taking big bites out of steel, but I can afford to not push so hard due to our low volume operations. We will exclusively be using Fusion 360 for CAM. Based on that information:
1) What years and model (dash number type) should I be looking for, or am I looking for a unicorn?
2) Were linear rail and HT model combinations even an option? If not, can linear rail models run the 10k spindle?
3) What is considered high and low hours respectively on these years 95-2001?
4) I am budgeting for replacing the spindle, at least 1 ball screw, axis thrust bearings, and possibly new spindle vector drive (Glentek amp from Calmotion). What other expensive maintenance parts should I consider?
5) We get an educational discount from Calmotion, fyi. I don’t know that I’m at liberty to discuss, but it helps significantly.
6) I realize machine prices varies by location and condition, but was is a reasonable price for a well taken care of 4020 that may need some minor maintenance, excluding rigging?
7) If I end up with a box way machine, what’s a reasonable cost to have the turcite replaced?
8) I realize rigging prices significantly vary across the country. What would be considered low vs high cost for rigging at both ends (pickup and delivery).
9) Is it reasonable to think that a $20k budget, excluding rigging, would get a machine and bring the maintenance up to spec is achievable?
I appreciate any and all feedback. If you happen to know of a unicorn like this for sale, feel free to put me in contact.
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