machining titanium

[machinedudester]

My boss wants me to machine titanium 6AL-4V annealled on a Haas GR512 that has a 15 hp spindle with 17 ft-lb max torgue @4600 rpm and I just do not think it will work on this machine. It is not rigid enough and does not have enough torgue in my opinion. Does anyone agree with me or not and why? Thanks.

[mcpgmr]

I don't think it will be a problem. I cut it just about everyday. Solid carbide 120 sf .002 chip load. We have a few Hass VF's and they seem to handle it ok. What size e.m.'s are you going to be using?

[gcode]

quote:

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Haas GR512

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Isn't this a gantry sytle router designed

for plastic , wood and light duty aluminum work?

You might be OK with small diameter tools but

I doubt it will do any serious roughing.

[machinedudester]

This machine is a gantry and is much larger than a VF and I need to drill and bore or ream some very tight tolerances +/-.0001". I did some drilling with a .390" cobalt taper length drill. I used the mastercam speeds of 130rpm at .2 feed and if I increased the feed it made the rpms jump back and forth more and more. These are very unigue parts, I have to go through .625" thick ti. then aluminum then air then aluminum and then back through .625" of ti. again, a total of 5 inches. There are already holes at .375". I would like to mill them but how can I reach the bottom in such a small diameter?

[CAM-mando]

quote:

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Haas GR512... very tight tolerances +/-.0001"

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[5 AX]

I wouldn't recommend reaming titanium....

[Ron Branch @ Verisurf]

Wow just Wow is all I can say

[machinedudester]

Just wow? Can't you elaborate just a little?

[generaldisarray]

So you have a 3/8 hole you are enlarging to what size? Your fluctuating rpm is a sign you are out of torque. With a .390 drill? with a .375 start hole?

[Ron Branch @ Verisurf]

The WOW comes from you being stuck with such a job on a router. +/-.0001 on a million machine would be a task, much less a router IMHO. That machine is a router not a true milling machine. Like said before you do not have the torque needed. I doubt you have the rigidity needed, and I am almost shore you are pushing your true position tolerance to the max doing everything you can just hold what you are holding. The added cost to the job, the added risk of scrapping the parts just make me feels bad for you. I wish you the best, but there are the hard jobs, the insane jobs, and the what was someone thinking job.

[Goldorak]

on a high end Okuma mill, i can barely hold .0002 tol in titanium , i really don't want to try this on a router

[Josh T™]

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I doubt it will do any serious roughing

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I know first hand that it won't. One of our customers has a GR712 and trust me... it won't take it. Sounds like your boss is an optimist and they have no place in the world of machining.

 

"The road to failure is paved with good intentions"

 

HTH

Josh

[Mic6]

quote:

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"The road to failure is paved with good intentions"

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That was deep

[Rob @ Target Machine]

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I wish you the best, but there are the hard jobs, the insane jobs, and the what was someone thinking job.

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AMEN!

 

I would use a jig bore with a high speed head and a long shank cbn wheel to size those holes. With a tolerance so tight, inline is implied.

 

 

IMHO You are on the wrong machine.

[TR Mfg.]

"Haas GR512... very tight tolerances +/-.0001"

I would rate this as nearly impossible to do with any consistency. You might get lucky and get one good part but I wouldn’t bet you can do two in a row! Don’t let it be your fault this doesn’t work. IMO you are exceeding the design intention of the machine.