Setting up a Rbotic Milling & Cutting System for Creative Work

[corey]

Hello there,

We are planning to setup a design & production consultancy specializing in using robotic arm as a principle production method in Taipei, Taiwan. We ran into a few problems and had a few questions.

1) Will an older KUKA robotic arm  work with KRC4?

2) Would you suggest SprutCAM or PowerMill? I quoted the Taiwan vendor for SprutCAM and it is 30000 USD for initial purchase and extra 3000 USD yearly for upgrades and maintenance, is that right? It seems quite expensive.

3) How hard is it to bypass System Integrator and do system integration ourselves with a mix of new and old equipments? Is it very hard to calibrate all the equipments and connecting them to the controller (we are educated as architectural designers with no experience in robotic system except for a Lulzbot Taz 3D printer)? What's the possibility of damaging my equipment if i made a rookie mistake?

4) Do you have any suggested sellers for reasonably priced: spindles, tool rack with calibrators, linear tracks, hotwire cutters?

5) If i buy a KUKA robot that is not already listed in KUKA|prc, will it be hard to make our own robot? Is there a tutorial?

6) What is general failure rate of a KUKA robotic arm if we are using it to mill wood 10hrs a day?

Thank you!!!!

[Johannes @ Robots in Architecture]

Hello Corey,

That sounds exciting! Regarding your questions:
1) No, but controllers are expensive to buy separately anyway so it makes sense to buy the robot and the controller together.
2) Both are good programs for milling. SprutCAM is one of the more affordable programs, so 30.000USD seem to be a bit much to me. We can import G-code via KUKA|prc so you could save money by buying just the 5-axis module and not the robot module, at least at the beginning while money is tight.
3) Depends, if you need it quickly and professionally it makes sense to get an integrator. That being said it's definitely possible to get the robot started by yourself, it only gets complicated if you have to comply with any safety regulations where you need some kind of special license. If you set up safety areas etc. you can greatly reduce the risk of rookie errors damaging the robot, but 100% safety doesn't really exist.
4) KUKA themselves uses spindles by HSD for their milling robots, we bought an HiTeco spindle a while ago. There is also a wide range of no-name spindles from China. If you want to use a linear track you will need a controller that can drive an additional axis. Upgrades are expensive, so this is something to consider during the initial purchase. You can usually buy used robots and equipment through KUKA, and there are also sellers like GlobalRobots.
5) We integrate new KUKA robots for free for our members, don't worry about that.
6) The MTBF (mean time between failure) of a KUKA robot is said to be around 80.000 hours. At 10h per day that would be 22 years. Of course you can always get a faulty unit or be especially unlucky, but even if you only get a half the hours it would still be 10 years.

In around two months there will be the Rob|Arch conference in Sydney, that would be a good place to get started. As a student member the registration fee is very affordable as well.

Best,
Johannes

[corey]

Thank you Johannes!

You are always the best! That solves quite a lot of problems that have plaguing us these few months.

We are now talking to an integrator in Taiwan and listed a series of requirements including KRC4 Robot for wood and foam milling, 10m linear track, automatic tool change, dust suction system, e-stop, rotary table. They are warning us the quote might exceed 280,000 Euro. They suggested us using a KRC2 robot which might reduce the cost by 20%.

I was wondering what is the limit of KRC2 compared to KRC4? Does it severely limit the file size we can import which means limits the complexity of parts we can make?

We are among the first to register the Sydney conference! Can't wait to meet you there! We will try out best to not bugging you like mosquitos with our endless questions. haha~

[Johannes @ Robots in Architecture]

Hey,

Looking forward to seeing you at Rob|Arch then, don't worry about the questions!
Personally 280.000EUR seem to be quite much, that should get you one of the nicest milling setups anywhere. The -20% (= -56.000) seem like a plausible difference between a new KRC4 and a used KRC2 robot, however I wouldn't buy a high-end setup for 220.000EUR and then put in a used robot.

A colleague of mine recently got a barely used KRC2 robot (KR180 or so) with 6m of rail for 25.000EUR (admittedly a good catch, more or less directly from a factory. Would cost more if you bought it from a seller that provides warranty etc.). Cheaper turntables usually go for around 7000EUR, while a nice milling spindle (10kW with HSK etc.) is 5000EUR. Add some smaller things, a few thousand EUR for safety fences, shipping, and installation and I would have assumed that it's possible to do it with an initial investment of 50-60.000EUR for the hardware. Things like safety certifications can drive the price slightly further up, I think we paid around 10.000EUR for an 80 pages report that basically just warned us of the dangers of wood dust ;)

Best,
Johannes

[corey]

Hello Johannes,

Thank you again so much for your quick and comprehensive response! Your information is very useful us in negotiations with those suppliers and established a based line for us. We definitely won't be looking for a used robot with high end setup, it's like putting a ferrari engine in a golf cart.

We also definitely don't need those reports as we probably won't be hiring anyone but ourselves to work on projects until the investment can be leveled by job profits. As we are sure we know the danger of wood dust! haha~

Thank you again for your patience answering our questions! Now with more information at hand we can try to talk to different System Integrators to negotiate knowing we can always buy from Global Robots.

Best,
Corey

[bsuroboticslab]

Hi Johannes!

There's some good info for us in here too!  We are about ready to move on a rotary axis upgrade and a new milling spindle.  I have been looking at a 6kW ER32 collet spindle from HSD, which is very reasonably priced.  In fact, we can afford twice what they've quoted us.  With our KR60, if we want to mill hardwood, would you suggest going higher than 6kW?  How much of a disadvantage is not having a quick tool change capability for our spindle?  I imagine the main advantage (for a non-production shop) is being able to pre-measure all your tools for a given job.  Would you agree?

Thanks! -Dan

[Johannes @ Robots in Architecture]

Hello Dan,

While we do quite a bit of milling, I'm not really an expert. Anyway, from my experience 6kW is plenty, though sometimes 8kW spindles are even cheaper as they seem to be more popular. Personally I would definitely go for a tool holder like HSK or ISO so that you do not have to calibrate your tools all the time - as you said correctly. I've never found too much use for a fully automated tool changing rack in a university environment where speed is not as important.
One important consideration for a spindle is cooling. Personally I'm tending towards air cooling as there is one less part that can break - just a simple fan, no leaking tubes, no pumps, no problem if you don't use it for a couple of weeks. Water cooling has its obvious advantages as well - if you are using the robot exclusively and frequently for milling it definitely makes sense to use it!

Best,
Johannes

[happytriger2000]

Sounds like many people are heding towards the Robotic Milling nowadays:

https://www.youtube.com/watch?v=Qq0-dIsNDB0

[di]

hey corey 
how did your set up work out? we are in a similar endeavour as you guys were a year ago... was curious as to which path you took when buying.
best
diego

[corey]

Hello Di!,

I am sorry it has been a while before i logged in.

We had some ups and downs regarding the setup. We initially planned to buy second hand robots from Global robots and get them integrated in Taiwan. But turns out Taiwan has heavy import tax and integrator are reluctant to integrate such an open system - they are more accustomed to rigid industrial settings.

In the end, after sitting down with a few of Taiwanese integrator and failed the negotiation, we finally found a young team of integrator that are willing to integrate.

Now, we are integrating an ABB 6700 -245 3.0 robot with a HSD ES362 spindle, a 5m local made track with ABB motors for multi axis movement and a MID 500 turn table.

It's nice to know so many people are joining this evolution! I hope we can all keep contact.

I can be reached at +886 966510996 or coreymails@gmail.com if you have further questions. Or we can discuss here too!