O/T Machining Beryllium Copper

[TeccBoxx]

I am going to me machining some beryllium copper here shortly for a mold and I was wondering if anyone had any tips on machining it? It is my first time touching copper as well as the guys I work with here. I did a couple quick facing passes but before I go and do something stupid I wanted to check especially since this stuff costs so damn much.

[moldmaker10]

Are you sure it is beryllium copper. I will not allow the stuff in my shop. Extremely toxic. Only material I ever saw come in with a skull and crossbones sticker on it. Whatever you do, do not grind that crap, the dust will get in your lungs. If you have to grind it flood the crap out of it and wear a resperator.

[TeccBoxx]

hey moldmaker yeah it is beryllium. I am not that excited about it either, I have went throught the MSDS a couple times and know that it is very toxic especially when grinding and sanding. However I do not and will not plan to grind it or sand it.period. Plus I will be taking some extream measures when it comes time to machine it.

[Phil Orenstein]

If my memory serves me well, you may be referring to an aluminum alloy with beryllium copper which is copperish in color. It is a little harder than 7075 and is sometimes used for inserts and thin features to withstand the hi pressure. As I recall we machined it similar to aluminum values for cutters and feeds & speeds.

 

Phil

[Guest]

Just be very careful, a chip or sliver should be treated immediately, blood poisoning is a real problem.

[mike_f]

we machine quite a bit of it. make sure you use very sharp tooling especially if you need to hold any kind of close flatness tol. on thin parts. it has a lot of stress and dull tools, even tools that look "ok" and are holding finish and size requirements, will cause quite a bit of warping. use pcd inserts on face mills if you have access to them otherwise use "up sharp" ground periphery inserts, if its an option have the material stress relieved first. hth

[Harryman]

Find out what it's going to cost to get rid of the coolant before you agree on a price for the job.

[SpazMachine]

With sharp tools this stuff will cut fairly well. Drilling it isn't any fun though. I don't remember exact numbers but I beleive 15 SFM or something like that with a fairly agressive chip load. Keep the drills sharp and stop the instant it makes any noises. Don't think it's going to be okay because it's almost to the bottom.

[gcode]

quote:

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stop the instant it makes any noises

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+1 to that!!!

That squealing noise you hear is part and drill

joining together by the process of friction welding

[Hardmill]

Lightly kiss one face of your drill point so

it will cut a little o/s and it will drill

like a dream. No binding at all, I usually drill

one size smaller.

 

PEACE

[jrykrl]

beryllium copper, that's scary, I always get a chip of my material in my hand, or boot!!

jer teh toxic shock

[Lars Christensen]

Tazzer,

And no Sinker EDM or Holepop in this material, submerged WEDM is ok though.

Have a guy here at the shop, who use to machine that stuff, he told me that there is some health kit, he use to have if something should get wrong, he used to get it from the customer who was Kodak. You might want to look into that

 

Lars

[mold100]

Dont Panic, its not that bad, I try to keep BeCu in my niche because alot of people wont touch it, More than likely what your going to be cutting if its new is Moldmax and its 2-3% Be.

 

quote:

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With sharp tools this stuff will cut fairly well. Drilling it isn't any fun though. I don't remember exact numbers but I beleive 15 SFM or something like that with a fairly agressive chip load. Keep the drills sharp and stop the instant it makes any noises. Don't think it's going to be okay because it's almost to the bottom.

---

.

I disagree - Sharp drill wont get you real far - Take hardmills adice dull 1 flute- you kind of want the drill to cut a little big so if your pecking the side walls wont cause grief, the stuff gets a little warm and it grabs everything it can causing a drill that is to sharp to grab and tend to want to rib your part out of the vise.

I also have seen and tried a couple times if you take a phone book and in it put a couple sheets of 220 sand paper in it and drill through it this will just take the grabbing edge off the drill.When I tap it I only try to maintain 60% - 65% thread so I drill over tap drill size for less tapping grief.

 

As far as EDM I have burned it and Burned it, copper impregnated graphite C3 comparable works well neg polarity 1st 2 or 3 hits its gonna eat some trodes its Thermal Conductivity is probably 60 times greater than H-13. I have and would HIGHLY recomend DO NOT INHALE THE FUMES OR AS little smoke as possible, use a good sucker system.

[Code_Breaker]

Hey guys, why all the scare tactics? I have been machining BeCu for 15 years--both hi-hard and lo-hard.

 

Here are some tips:

 

Drilling:

 

[*]Use standard drills with an altered tip ("plain point") to a "brass point" reducing the web to 5 degree helix angle.

[*]If hole size is not critical use a tip point off-centered .010-.015. This will give you a built-in relief for deep holes

[*]Use peck drilling for holes deeper than 1x drill diameter and retract out of the hole after each .200 drilled depth.

[*]Cutting speed is 100-130 fpm.

[*]Use "liquid" flood coolant in oppose to "air" mist.

Milling:

 

[*]Use tools with positive rake angles.

[*]Cutting speed/feed for solid carbide ranges from 260-330 fpm and .0005-.004 inch/tooth, for Carbide indexable insert from 490-660 fpm with .003-.008 inch/tooth, HSS 150-200 fpm with .002-.014 inch/tooth.

[*]For coated HSS--increase cutting speed 30%

[*]the spread per tooth (above) depends on the radial depth of cut and cutter diameter.

[*]Face milling, double the chip load per tooth.

[*]Use "liquid" flood coolant in oppose to "air" mist.

Tapping:

 

[*]Use taps with straight flutes, blind and thru holes

[*]Cutting speed for lo-hard is 19.6 and for hi-hard is 26.2 fpm

[*]Use cutting compound or cutting oil, else "liquid" flood coolant NEVER MIST.

Go on-line and use keywords: MOLDMAX and PROTHERM. For other processes, look up Uddeholm and BrushWellman web sites.

 

Also, look up article in Plastics Machinery & Equipment Feb., 1991 under "mold & die corner". Very helpful.

 

HTH

HF

 

Code_Breaker

[herbert west]

Tazzer:I used to wire edm, conventional edm, drill, mill, grind, and heat treat this stuff for over 11 years. Very common in mold making to transfer heat and certain prototype fighter plane parts. We did so much of this stuff on a production basis that osha slapped a air meter on my back to test for contamination. Do wear a high quality respirator though and not some cheap paper dust mask. For drilling use a split point grind at about 135 deg. If it's heat treated you'll be using carbide spade drills. For milling go with high helix solid carbide, 3 flute. The key is to not let the material know it's being cut. With this in mind, the methods become quite clear.

[Code_Breaker]

quote:

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The key is to not let the material know it's being cut.

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+1000

 

Code_Breaker

[TeccBoxx]

Awesome guys, I really appreciate all the info you guys have provided. I was able to contact a shop today that deals with BeCu on occasion and gave us some scraps to play with. Again thanks a lot and I will keep you posted on how it turns out, after all this is my first cavity and first time messing with BeCu as previously noted.

 

Thanks Again.

[Bill Sp]

We will not machine or grind it in our shop. Instead we use Moldstar 90, or Moldstar 150, it is Beryllium-Free. Performance alloys has excellent information on the materials.

http://www.performancealloys.net/