Running multiple machines

[REVCAM_Bob]

I would like to here what you guys have to say / suggest about
one person running multiple machines.

We are looking for ways to train people how to get more done i.e. more
spindle time.

Here is a typical problem we encounter: One guy running two machines
Both machines are not running, in one machine is a large part that requires
a 20 minute setup, and will then run for about an hour unattended. For the other machine we have lined up a series of 10 parts, each of which requires
a 3 minute setup and have 10 minutes of run time. Which machines does he
tackle first? or does he do both?

How much spindle time per guy or per machine does a shop get per hour
the guy runs it?

[DareBee]

Assuming both machines are running work that is the same priority. I feel it is more productive to keep the long runtime going non-stop and fill in with the short runtime.
It is hard to get much done in a 10 minute cycle.
Maybe you should give some thought to a manual load pallet for the short run parts, that way machine load time will be less than a minute instead of three.
No matterwhatyou do ther will be times when both machines are waiting for setup at some point in time.

[Geof]

Originally Posted by REVCAM_Bob ....Here is a typical problem we encounter: One guy running two machines, both machines are not running, in one machine is a large part that requires a 20 minute setup, and will then run for about an hour unattended. For the other machine we have lined up a series of 10 parts, each of which requires a 3 minute setup and have 10 minutes of run time. Which machines does he tackle first? or does he do both?....

Tackle long runtime machine first and the result is you miss two loads on the short runtime machine and it takes 23 minutes to get both machines running.

Tackle short runtime machine first and you get this machine running in 3 minutes. At the end of 13 minutes you have the long runtime machine partly loaded and you stop to reload the the short runtime machine, get it going again by 16 minutes and go back to the other machine. At the end of 26 minutes the long runtime machine is up and running and the short runtime machine is ready for reloading and you have two parts off this machine.

The choice seems simple to me.

[dkowalcz]

I find it works to try and even out the times between two machines so that the work paces out well. Spend an hour setting everything up in the morning, then run two machines all day - say machine 1 spits out a part every 5 minutes, during which I can get 3 on machine 2. 3, 1, 3, 1, 3, 1, and the day is over...

Note that it always takes longer to run two machines with one guy - he has to do everything he'd ordinarily do to run each seperately, plus run back and forth.

The exception is if the deadline is bearing down (they need it NOW!!!) - I just stand on the one machine that has to do it until it's done. Also, if the cycle is under a minute, just camp one machine - it doesn't work to try to be quicker than that.

In your scenario, I'd actually start the "10 minuter" first and get it moving, and then use the first two or three 10 minute intervals to set up the hour long cut. Interesting that my instinct differs from DareBee's, maybe we should work it out longhand and see which is quicker - maybe it's a wash?

[Geof]

Maybe it's a wash?

I think it is always more productive to get the short runtime machine going first. Even if in this example the 20 minute load extended to 25 minutes because of the interruption it will still work out more productive.

[REVCAM_Bob]

Yes, it is interesting how answers come back different. I find the same in
my shop. It makes it hard to train when 3 different managers have 3 different
answers as to the correct approach.

Has anyone seen any theory books, training material or other examples?

[Geof]

[QUOTE=REVCAM_Bob... It makes it hard to train when 3 different managers have 3 different answers as to the correct approach...[/QUOTE]

Given that with two machines you only have two options, assuming the guy does not have four arms and can reach both machines simultaneously, I think the manager that comes up with a third option should be given a gold star for ingenuity.

[lakeside]

I Have Had Theee PrototRak Running At The Same Time But When Cycle Time Made That Pracital. Most Manger Are So Consumed By The Ideas Of Jit And Pull System And Multi-tasking There Are Living A Pipe Dream. Why Would Some One Bust There Butt Running More Than One Machine If It Not Pracital Let Face The Fact That Now A Day A Good Machinist Can Tell His Boss To Stick it Up His Septic Chute Because Companies Are A Dime A Dozen That Need The Skill We Have

[Edster]

I'd fire you if you told me that at my shop

I run two machines all the time. I'd get the one with the longer cycle time set up and running first. Then use the time between cycles to set up the other machine. That way I'm not running all over the place.

[WhiteTiger]

I'm not so sure about the hop back and forth scenario. Seems like a recipe for damage/injury to me.

Do half of one setup. then go do something entirely different, then come back and pick up the unfinished long job. Doesn't seem particularly economical to me to be gambling with waste, damage and injury for the sake of a couple cigarettes worth of time.


Tiger

[Geof]

Originally Posted by WhiteTiger I'm not so sure about the hop back and forth scenario. Seems like a recipe for damage/injury to me. Do half of one setup. then go do something entirely different, then come back and pick up the unfinished long job. Doesn't seem particularly economical to me to be gambling with waste, damage and injury for the sake of a couple cigarettes worth of time. Tiger

Okay, load the short runtime machine first and then let it sit for ten minutes or so until the other is done. This way you get one part off it during the first 23 minutes.

[lakeside]

[QUOTE=Edster]I'd fire you if you told me that at my shop

AND I'VE BEEN FIRED FOR THAT. MACHINE SHOPS ARE A DIME A DOZEN LOOK AT MOSTER CAREER BUILDS OR THIS SITE(HOW MANY PROGRAMMING JOBS DO YOU SEE MR MACHINE SHOP OWNER) IF YOU HAVE THE SKILL YOU DO NEED TO PUT UP WITH “DO THIS OR ELSE”. 20 YEARS AGO MACHINE SHOP HAD A LARGE WORK FORCE TO DRAW FROM BUT WHEN A FRAMER CAN MAKE TWICE AS MUCH AS A MACHINIST WHY WOULD A KID SPEND HIS TIME TO MAKE YOU RICH OH IF I RUN TWO MACHINE FOR YOU, YOU MAKE TWICE AS MUCH PER HOUR ON ME AND WHAT YOU'LL GIVE ME $1.00/HOUR MORE. WHAT THAT IN MY POCKET $30/WEEK AFTER TAXES I SPEND MORE ON TIPS IN A WEEK THAN THAT. SO YES MACHINE SHOP ARE A DIME A DOZEN AND IF YOUR BOSS EVER SAYS “DO THIS OR ELSE” LAUGH IN HIS FACE