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New to CNC - Buying First Mill


RetiredVegabond
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One job that could be 2000 parts a year correct? Again using the 3.75 hour per part run time you would need to hit 150 hours a week of production capability doing it with a vertical is not going to cut it again in my opinion. If you go back to your customer and lay out a solid business plan where you show them your method to do what they are after will they be willing to provide you with NRE money to get started? Maybe 6 months of money up front? They need the parts and you have the method to help them get there. You must have their trust or it would not even be on the table. You can go the route you are trying and fight and fight barley getting by or you can think outside of the box and present a solid case for a direction that is going to give the best parts possible and the lowest price. Give you comfort that you will be around 7 years from now doing that work and keep your sanity all the way through the process. I would really sit down and break down all the cost not just a machine at this point. What is going to be your tooling cost per month, Electric, Rent, Toilet Paper, Soap, How much money will you make off selling the scrap. I got a customer that figured he will make $2k a month of job he just got, that he figured will cover the cost of his tooling. That becomes a break even item. Sorry, but I have run some small shops and some big shops and ROI is one of the most misunderstood concepts people face in today's manufacturing.

 

Bob you got where you are and you do great work, If you had a 7 year contract of work and knew you could get 2000 parts a year of tool steel grade parts would you want to do it on your HAAS or Makino?

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Bob you got where you are and you do great work, If you had a 7 year contract of work and knew you could get 2000 parts a year of tool steel grade parts would you want to do it on your HAAS or Makino?

 

I would order a pallet system, add my A51 to it and run 24 hours a day. Shortly thereafter (a few months) if things were going well I would be adding a second machine to the cell. My Haas wouldn't even enter this equation except maybe prepping fixtures for the cell.

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I think a critical thing here is when he said "machined on all 6 sides"..... did he mean machined on front and back, and contoured around the outside? Or machined on all 6 sides - like, actual features on all 6 sides. If the former - a nice VMC with a 10 pallet Erowa Robot Easy system would be perfect. If the latter - he needs an HMC at the minimum.

 

He did mention all the drilling was from the same side, so I'm guessing it's a 2 operation VMC part.

 

Robot_Easy_Titelbild_03.jpg

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Thanks for the input guys. I've gone over the numbers in great detail and the margins are good. Millman makes a good point: 2000 pieces will be unattainable. The part I described above is the worst case. It's difficult to say specifically what the demand will be (long cycle time parts or short) since this is a family of parts and the customers order mix will vary every week. I had one of the equipment vendors run a simulation of run times. They concluded that the run time of my parts ranged from 26 minutes to 5.5 hours. I'm betting reality is more like 1-8 hours. Rerunning the business case with 1000 parts still makes this a viable project assuming the average part requires 4 hours. My financial situation prevents me from adding any additional equipment (or more sophisticated/more expensive equipment) until the cash flow from this job kicks in. Of course that's dependent on how much I need to spend on work holding and tooling. I should probably also note that production rates are planned to ramp up over the first two years.

 

Where do Schunk, Iscar and Sanvik tool holders fall in the hierarchy of quality?

Stay away from Iscar and especially Sandvik. The latter is WAY overpriced. Command, HPI and some other good brands will get you going.

Yes, ferrari is nice, but this ford will get you there as well. As much as I love good quality machines (makino, mori, matsura, okk +++) my first would be an economy one. Exactly the ones that you are looking at..

Don't let them distract you. It's NOT their money ;-)

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Schunk are great value for money.

So are Haimer tool holders.

 

Be sooooooooooooo careful with this. I've seen it a few times before where the path is paved with gold and promises and in these cases, contracts never fully materialised or companies got bought and the work went somewhere else leaving the subby high and dry.

Even saw once where a new purchasing guy walked in and he was the new great white hope, and turned it all upside down for one subby, pulling 50% overnight.

 

I don't know all the facts, but if it were me, I'd go for something like a Quaser or Doosan vertical with box ways or big roller ways ie rigid with BT40 big plus.

Get as big a stroke as possible to get most jobs on it so you can fill the table.

This is your cheapest option and run this in conjunction with a shop down the road who can also work with you sharing your load.

See how things develop and then look at going from there - either a second machine or then a multi pallet hori etc.

 

Good luck but don't sign your house away on the finance for this....

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If it were my money I would buy the right machine for the job banking on long-term success. The difference between a Ferrari and a Ford is the Ferrari will get you there 25% faster than the Ford. The Makino VMC will literally get the job done 25% faster than the Haas in steel and that is not an exaggeration (probably pretty conservative). Figure your shop is running these parts and making $1k per day with an 'economy' machine. The Makino (or similar) VMC will be running $1250+ per day which works out to $5k per month of increased revenue, single shift. The difference in machine cost or monthly payment works out to ~$1000 per month. Which machine is more expensive, the one that costs $60k more and makes you $60k more per year and lasts 20 years or the economy machine that saves you $60k in purchase price, you have to replace the spindle once a year because it wasn't built right, the machine is junk in 5 years, and the cycle times are 25% longer?

 

Most shops don't start with a contract in place guaranteeing work they can build around. If the work is there and you are confident that it will consistently be there for the duration then by all means set up your shop for long term success and buy nice equipment. Don't take my word for it though. Have the machine vendors cut a piece for you. It will really open your eyes to the difference in cycle times and quality.

 

Other things to consider:

1. Are the ball screws core cooled? This keeps temperature consistent resulting in better accuracy and longer machine life

 

2. Is there a spindle chiller? Again, keeps the spindle cool prolonging bearing life and resulting in better accuracy

 

3. Can tools be loaded and unloaded in the tool magazine while the machine is running? In a production environment this is key because you don't have to stop the machine to replace worn cutters and you can set up tools for the next job while the machine is running. Ultimately a HUGE time saver.

 

4. How does the control handle tools? On both of my Makinos I can have tool numbers up to 9999 standard. This allows me to assign every tool a unique number. If tool 63 is loaded in the machine it will ALWAYS be a 3/8" Hanita Vari mill with 4 flutes and TiAlN coating. My Haas (2008 vintage) requires renumbering tools because it can only have 200. On one job tool 18 might be a drill, on the next job it might be a tap...

 

5. Multiple block skip. This is a fantastic feature allowing ten total block skip commands that can be turned on or off while the machine is running. I have one of mine set up to activate tool break detection and another activates tool setting. If I step away from the machine for a few minutes and I want to make sure the tools are checked for breakage I simply activate block skip 9 (/9) and it starts break detecting every tool. If I need all tools to be re-set on the first cycle because I need the utmost in accuracy I activate /8 and it sets every tool. When the first cycle is done I turn off /8 and it runs normally.

 

These are real time savers and they allow for more time in the cut and less time dicking around with setup. Beyond speed, rigidity, reliability and accuracy these are the sorts of features that come with a nicer machine.

 

Just to clarify, I am not advocating going out and buying a horizontal machine with a cell system. That is what I would do given my current equipment, customer base, and work load. I would definitely not buy a machine based solely on price however. You want to get a machine that can actually do the work and do it well. Get a machine that is designed to cut steel on a production level or you will be doing yourself a disservice. Buy the right tools, tool holders, and fixtures for the job and you will come out miles ahead in the long run. They cost more up front but they will pay for themselves many times over.

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I admire you Bob - doing what you do and the way you do it, and also how you have got to where you are in a very short time.

We have 11 cnc's in here now (7 verticals, 2 lathes and protorak mill/lathe) and I know we should get a 5 pallet hori.

But learning curve and spindle down time etc frightens me to death.

We multi man and keep most things running and keep up with demand.

What's that saying - work faster and harder not smarter?

Or something like that :D

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Another thing to consider is the replacement part availability. I know that Makino has stocked parts for every machine for the last 20 years.. least it seems this way. I do machine repair and I can tell you first and foremost it's worth every penny to buy a better machine. for example to rebuild a Haas spindle looking at about $2k in bearings... for a makino its more like $5k because of the accuracy and quality of these bearings. Right now I'm working on replacing a bearing for the B axis on an A71 it costs over $10k the customer didn't even flinch to replace it cause the machine is of such high quality. and can expect another 20 years out of it. if it were a lower quality machine it would now be a boat anchor.

 

Hyundai is made right across the street from Doosan in korea. both are good machines.

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I guess I'm going to be the first one to throw this out there.

This is a pipe dream for most of us with 30+ years of experience.

New to cnc machining, lights out operating, a little bit of hard milling (RC60)?

Come on guys, throw me a fricken bone here :)

I say, purchase all three machines or just cut to the quick and go with 3 Toyoda horizontals.

Such are dreams.

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I guess I'm going to be the first one to throw this out there.

This is a pipe dream for most of us with 30+ years of experience.

New to cnc machining, lights out operating, a little bit of hard milling (RC60)?

Come on guys, throw me a fricken bone here :)

I say, purchase all three machines or just cut to the quick and go with 3 Toyoda horizontals.

Such are dreams.

 

Yes, I have been thinking the exact same thing :-)

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prolly cant go wrong with the Doosan or Haas.

part price, support and service are untouchable on the Haas, in this class. big plus= you are out of luck on the Haas. Cat40 have a little thinner flange so that would be an advantage in tool overhang, but not by much,

 

unless you want to do deep hole drilling or exotic material drilling, forgo the through spindle coolant.

10k vs12k is not goig to be huge. i really like the Haas 12k spindle. lots of nuts for a Haas. can't compare that with direct experience on a Doosan, but have only heard good things generally.

 

I disagree a bit with the through spindle coolant comment above. I really think this feature is well worth the money. Many of the new tooling options out there have specialized tool holders which can direct coolant directly on the insert where flood coolant can just not even compete. I mean carbide drills.... forget about high speed tooling, through spindle is the way of the future and any machine without this functionality just can not support many of the speeds and feeds some of the new tooling can. I do mean any disrespect to anyone but I think it would be a mistake to neglect the through spindle coolant as it will pay for itself if used properly in time.

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