Avoid Loading New Billet On Optional Stop

[Joey]

Hi guys

Is there any code I can use within a program to disable chuck opening whilst
the machine is stopped during an M01 optional stop.
During production runs it is easy to switch off for a moment, for example when doing a swarf removal under an M01 and loading a new billet instead !!
We`ve had quite a few pile ups.

Controls used are Mazatrol 640T and M Plus

Many thanks for any help

[integrexe410]

not that i know of, i presume you mean it isnt opening automatically and someone is physically opening the jaws when they shouldnt be.

I dont think much can be done, other than moving the foot pedals out of foots reach when you start a new billet, is it necessary to have the optional stop?

[Joey]

hi integrexe410
Yes the operator is opening the chuck when they shouldn`t.
Sometimes there are too many stops within a prog but I put that down to them adding them out of neccesity after having problems with the same part previously.
These are all existing programs within a production shop, and quite often
big batches of around 800 parts, running day and night, so although moving the foot pedal is a valid point it still relies on the operator.

I wish there was a way to program it or change the machine setup in some way.
I`m new to Mazak and have only basic programming knowledge on that control.

cheers mate

[integrexe410]

The only other thing i can think of would be a parameter change, i have no idea which one it would need to be and wouldnt reccomend it, it would be time consuming as you would need to then change that parameter again to enable the jaws to open normally.

Basically, (presuming it was possible) you'd have to change it when loading a billet and then when it stopped, change it again.

By the sounds of it you're machine doesnt have a subspindle, in which case you will be lucky, ive seen many a time when someone has a billet in the hd1 jaws and also head 2 jaws and tried to transfer it without taking the finished part out the 2nd side! major ball screw and z-axis damage.

[Joey]

Interesting you mention that, we are getting a sub-spindle machine in early december and work transfer was one of the questions I have for the training course.
If we want to work from a bar, for example :
turn the part - grip it with bored jaws on the sub spindle and drag it back in Z to a position suitable for parting off (which leaves the bar in position ready for the opp1 over again) Part off the job then drag it further back in Z and finish opp2 on the sub spindle.
So my question is - what happens if the parting off tool fails. Will the sub-spindle alarm out when it cant drag back in Z ? before any damage is done.
By what you`re saying integrexe410 the answer is no - it`ll break the machine. hmm thats a bummer.

To go back to the original discussion, well the chuck pedal is disabled during machining so if only there was a way to access that parameter within the start and stop parts of a program.

There again i bet Mazak and such companies make most of their dough from fixing crashes.

[Newby2]

I manage 3 mazaks at work, 2 with subspindles, and one with a tail stock. One of the 2 spindle machines is equipped with a parts catcher Most of the programs I write requiring a parting process utilize the parts catcher and I use the turret with a coolant activated barpuller to advance the bar for the next part. One job I ran was a 4500 piece order. In my opinion, using the subspindle as a parts catcher only increases the cycle time unless you are machining the back side of the part after the first side is finished in which you are setting yourself up for a big crash. If you are getting a new machine in December, might I suggest they install the parts catcher option. You will be amazed.

Steve

[integrexe410]

Ive worked almost all the mazak turning range, if you need a 2nd spindle then a multiplex is the way to go as opposed to the quick turn which is basically just a subspindle which will allow limited turning and milling.

The multiplex is in effect 2 lathes in 1 machine, it is easily possible to run 2 different bar loading jobs on each spindle as both have the same capability in terms of speed hp etc, both spindles also have their own turret so for example you could do a billet job whereby you would machine the first side, transfer it over to the 2nd then load another billet in the first side, youd make 2 parts in the time it would take to make 1.

With regards to bar work using the subspindle, there is no need to crash it, if you are not familiar with using the load meter detection then i suggest you read up on it, basically, if doing bar work the subspindle will rapid over to grip the part machined on the 1st side, both spindles will then turn in synch and the part of tool in 1st turret will be the cutting tool, you should in cases like this then utilise the load meter, programm it so that when the x axis (part off movement) gets to a certain load the tool will stop cutting and the machine will come up with an alarm, problem solved.

its not easy to crash spindles on bar work as long as you set the transfer correctly the first time the subspindle (or 2nd spindle if a multiplex,). will always rapid to the same positions, it will not go to the transfer position if the first side has not been machined.

As said before, if you are turning small parts using bar work which you should be as the spindle bore is something like Ø52 max if i remember correctly, then a parts catcher is a MUST, my old place of work bought a multiplex brand new a few years back, top of the range, pc fusion software the lot and the buyer forgot to specify he wanted a catcher, we were then seriously limited to the work we could do, we had the toolmaker make 1 up, an awespme piece of kit, ive never seen a toolmaker so good.

if you still have problems with operators crashing it i suggest you sack them lol

Hope all that helps

Gary@ forth tool and valve

[integrexe410]

Incidentally, just out of curiosity, where are you based and who is supplying commisioning the Mazak? i have just started a new job on a mazak which is new to me (more geared towards milling than turning) and have just completed my training course, which was crap, i didnt learn anything i didnt already know

Although the company who transported the 19 tonn machine and installed it done it well enough, the training left a lot to be desired

[Joey]

Ah sorry let me explain properly.
Based in West Sussex. was working (up till 2 weeks ago) for a CNC Production outfit that has a big range of Mazaks, including 2 multiplexes.
It was here that I came across this problem of operators crashing the machines,
I tried but failed to get a solution from any of the guys there about adding code to a prog or such like to overcome the problem of loading out of sync.

Although I have moved companies, I am still interested in finding a solution.
which I would relay back to my mates.

Ok so the new place only has 1 CNC lathe atm and the other on order is a Kia SKT250MS with Fanuc 18i control. C axis on both spindles, and Part catcher.
On the face of it they seem pretty similar to the SQT MS

Thanks for your interesting comments, and the heads up about the Loadmeter

[Newby2]

Gary...I have found that milling on a SQT is not that advantageous. With the limited HP and stability of the live tooling and the time it takes to interpolate between the spindle and the X axis, I have found it is faster to do the milling as a second op. I milled a run of bolt heads using the live tooling and found I could complete them in less time on a Bridgeport with a stacked slab mill. Also I manage one SQT that was crashed hard, (luckily before I got there)and now the turret is off center in Y. I have to shim the tooling .015" to get them to center. (boss won't give me the time to correct this issue)
I have to agree with your comment about sacking the operator if the machine is not operated properly, especially if this happens more than once.

Steve

[integrexe410]

I suppose its down to preference really, we didnt utilise the milling much on the SQT for anything more than drilling x-holes in a part which is more accurate and time saving than on a manual mill, a lot of the stuff we did was hydraulic pumps and the holes were simply a relief hole.

Any serious heavy milling was done on the multiplex, as a rule, our boss wanted parts coming off the machine completed, thus taking out the need for a 2nd op which would then require a 2nd operator, as often, whoever was running the mazak was often running 2 or 3 simultaneously.

Parts would come out the parts catcher completed and deburred in the machine, blown out and packed ready for shipping.

The issue you have with the y-axis being out 0.015" is a serious one, i would say to the boss that its time consuming to shim tools to get them on centre when he should be paying a maintenance engineer to take a couple of hours and sort the problem, maybe it's just me but i cant see how a precision part can be made from a machine that relies on little more than eyeballing the alignment of a tool, which no doubt increases set-up times and thereofore costs the company more money, thats just my opinion though, i am not in a position as high as you.

http://www.mcdowell-engineering.com/index.htm

http://home.btconnect.com/meservices/cnc-services.html

The latter of the 2 links are highly recomended, the boys running the company used to work for Mazak and will fix problems in a jiffy, if it can be done over the phone it will, both will offer helpful advice on the phone, if there is a parameter change for you're opyional stop problem those guys will know it.

Dont know who you currently use, just trying to help a little

Gary

[Lathejockeu81]

I know this thread has been sitting idle for a while, but the things discussed here sound like the issues we've dealt with at my shop.

For background: My official title is "Documentation Control Specialist" although that doesn't really describe my duties well. I work for a small to medium batch production shop that is part of a complete design to shipment fire fighting equipment manufacturer. We have a total of 11 Mazak lathes ranging from a SQT-15MS with Gantry loader(that will be sold soon) and a T32-3 controller to a new QTN 250M-II with a Matrix controller. Our operators are all button pushers that have little or no skills walking in the door, so naturally these problems described have been dealt with time and again for us.

1st Issue - Blanks being switched out at an M0 - the best solution we've come up with is to manually place a tool(as non-intrusively as possible) in the way of removing a partially completed part. This way, to switch out a blank would require manually moving the turret... so there's no excuse.

2nd Issue - Potential of finished blanks left in sub-spindle - we learned this one the hard way on our first Integrex 300-IISY... the head crashed into a finished part that was still sitting in the sub spindle. Our solution was to add a manual unit to the start of the program that brings the sub-spindle up to the main spindle, switching to approx. 50in/min feed before it reaches and feeds past the potential interference point. Our philosophy is that a (relatively) low feed overload is a lot better than cracking our spindle or having the sub-spindle rapid into the main spindle(I did that once due to a faulty restart and a dropped tool... not pretty... required hours of labor and cracking loose 6 bolts torqued to 1000ft/lbs to re-align the main spindle)

As for the misaligned turret. If your pins are okay, just make a long bar that you can stick into one of your tool stations. Use a #2 toolholder(I.D.) and an indicator to locate centerline(and gauge your progress) Crack loose the bolts that prevent your turret from turning, and thump the bar until things line up. Sounds crude but it works oh so well... we always check and (if needed)re-align turrets after even small crashes, and it's become a 20-30 minute process. Well worth every minute.