One Hit Machining

[CRPDGAZ]

Hi Folks, new to the forum although been involved with CNC since early 85'. Last year got involved with a One Hit Machining project that helped a local company improve manufacture time from 3hrs to 13mins. Is anyone out there using One Hit Machining on a daily basis with High Speed Machines?

I know it's a tall order but if anyone knows of any good books on the subject it would be greatly appreciated.

Best Wishes

Gary T

[Mouldmaker]

What do you mean by One Hit Machining? Its a phrase I never heard.

[CRPDGAZ]

Mouldmaker,

“One – Hit machining is the manufacture of a complete part/component in one set-up of the machine”

That is supposed to be the true definition. It's easier on a 4/5 axis VMC but we did the project on a three axis. The part was for the Aerospace Industry and went through three ops to get the part finished - this was reduced to one and the set-up time went from 2hrs 50 mins to 2 mins 16 secs.

It may be called something different where you are, but I only know it as One Hit.

Thanks

Gary T

[mrainey]

It's something most of us have always tried to do, whenever the workpiece and machine configuration allow - without giving it a fancy name.

[Rekd]

I've been doing it for years. More so this last year. Great for several reasons, like increased cycle times, less chance for scrap from finding out on operation 4 that operation 1 was bad, etc.

'Rekd

[Rekd]

BTW, if you're getting time reductions around 75% to 95%, you really need to be thankful that last guy that made those programs isn't working there any more!

'Rekd

[CRPDGAZ]

Thanks Matt,

It seems people here in the UK are just starting to try and develop it so there is a guideline to follow. Do you find if you plan it through properly you can achieve it whatever the job?
I am going to a press tool company on Thursday who are trying to develop it for small batches. How do you apply it or does it work with everything?

Gary T

[Rekd]

Originally posted by CRPDGAZ Thanks Matt, It seems people here in the UK are just starting to try and develop it so there is a guideline to follow. Do you find if you plan it through properly you can achieve it whatever the job? I am going to a press tool company on Thursday who are trying to develop it for small batches. How do you apply it or does it work with everything? Gary T

You're welcome, Gary.

This process will definately not work comlpetely for everything, but with proper planning can be applied to some extent to most jobs.

I don't think it's going to be something you can define in detail to be used as a guide. It will vary greatly from job to job.

HTH

'Rekd

[mrainey]

Once in a while you'll run into a situation where you're tempted to use marginal, or even inappropriate, tooling just so you can reach a particular feature and get it all in one operation. Cycle times and/or part quality can take a hit in some of these cases. You have to apply some common sense. "One Hit" doesn't work optimally for everything

Similar to managers that dictate that an HMC be tooled up with an absolute minimum number of tools, to save a few bucks on toolholders. You might indeed be able to make all your parts that way, but only after extending all the tools out so far that none of them cut very well. You have to take lighter cuts, the tools don't last, and the finish suffers. What's cheaper in the long run?

Good luck to you.

[camminc]

Hi, my name is Randy. See this site and look at the Video's and Stability Charts for review. Maybe this will help, thanks.

http://members.cox.net/camminc

[CRPDGAZ]

Thanks Randy,

Will have a look at them and let you know. I am now working with an Aerospace manufacturer who needs to improve their CNC capability so this may be useful

Regards

Gaz