Turning offset

[DavidB]

Hi huys two questions.

 

1, Is it possible in Mastercam to turn a diameter offset from X0 or is a 4 jaw the only option? I need to turn a diameter 35mm offset from the bar stock.

 

I can see that the X axis would have to move quickly to turn an offset diameter if it's possible.

 

 

2, Can an Integrex or Macturn turn offset diameters? Or is a 4 jaw required?

 

Thanks in advance

[Rick Henrickson 65]

I am not sure if the mac turn can but okuma does have lathes to do cranks

[DavidB]

Can Mastercam do it for a standard Lathe or is a 4 Jaw my only option?

[Rick Henrickson 65]

we turn off center but instead of a 4 jaw we use a modified technogrip which is a dovetail type fixture.

It requires preping the material before you use it

[DavidB]

Rick,

We use dovetails for 99% of our milling machines.

 

quote:

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technogrip

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Got any info?

[Hardmill]

One of our lathe guys here has done it with an

Okuma, but prefers to offset the chuck.

I dont know if MC outputs it.

 

 

PEACE

[Rick Henrickson 65]

http://www.technigrip.com/

 

We use the small one and sized it to a face plate.

we have locators on the face plate for different offsets

[kringd]

Get a magnetic chuck

[DavidB]

Cheers Rick

[DavidB]

Magnetic chucks are no good for Al

[Rick Henrickson 65]

My step brother lives in sydney I was thinking of visiting this fall I have never been.

Although Im not sure after watching wolf creek

[Hardmill]

quote:

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Magnetic chucks are no good for Al

---

That only counts if your standing in front of it

 

 

PEACE

[crazy^millman]

Well depending on the part and the length of the material and how much you are talking about I have done it with center drilled position and dead centers. I have also done it with split bushing bored to the throw amount and machined them that way as well. Say it is a 2" dia you make a 4 " dia bushing then bore a set of soft pie jaws to fit the 4" dia. Put your offset in the bushing then split it on the small side. Now you have the ability to make just about anything with a cam in it. Also if you did it right you could use features off of the part to time features to the cam or shift.

 

The other method is to put flats on excess of materail to reference your center drilled holes to. Then you got a flat and a circle to referecne your center drilled holes to. You could do as many lobs or cams as you need if you had the room. I have done 5 shifts this way and keep everything within .001 to each other. When you are done you grab your machine areas and machine off the excess.

 

HTH

[rot]

Do you have to run this off a bar? Could you get some pie jaws and mill a bore off center in the lathe the amount you need?

[DavidB]

Material is 7" Dia x 14" long 15-5PH S.S

I need to turn a 4" dia X 4" long spigot 35mm offset from the centre line of the stock.

 

Once I have this offset Dia I will turn the blank around and hold on the offset dia in a 3 jaw chuck to machine the remander of the billet.

[chris m]

Magnetic chucks work OK with aluminum if you have enough tailstock pressure....

 

I have never heard of anyone using Mastercam to do this, David, sorry

[Tim Simmermon]

David,

 

We turn eccentric diameters here, but the material is quite a bit smaller. We have two sets of centers on each end of the piece, one set on center, the other set at the eccentric distance. We turn the entire piece like usual, then turn the eccentric between centers. I wouldn't recommend this for you with the size of your material. If your control has it, polygonal turning might help you.