Engraving and cutting brass

[buildswithbrian]

Hey guys,
so last night I engraved some brass ( project for my daughter) and it took
A couple tries but I got the engraving to work .
My trouble is with profiling the part cut out, I’ve broken two 1/16 end mills So far,
just wondering what the recommended depth of cut, feeds/speeds are for free machining brass.
Brass is 1/16” thick material

Any help would be
Much appreciated

Brian

[Deleted]

Remember that brass contains lead so lacquer it to protect your daughter and clean up (yourself and work area) and dispose of waste properly.

[buildswithbrian]

Dec 12, 2018 9:04:37 GMT -5 @fean said:

Remember that brass contains lead so lacquer it to protect your daughter and clean up (yourself and work area) and dispose of waste properly.

Fean,
My daughter is 21 and won’t be putting it in her mouth 😁
But I dig where you’re coming from,
I appreciate the concern. 👍

[Deleted]

Dec 12, 2018 21:49:33 GMT -5 buildswithbrian said:

Dec 12, 2018 9:04:37 GMT -5 @fean said:

Remember that brass contains lead so lacquer it to protect your daughter and clean up (yourself and work area) and dispose of waste properly.

Fean,
My daughter is 21 and won’t be putting it in her mouth 😁
But I dig where you’re coming from,
I appreciate the concern. 👍

Lead exposure bioaccumulates throughout your life, actually longer since conception to birth also counts, so it applies to all ages and especially you since you're doing the machining. You don't have to put it in your mouth as lead is absorbed predominantly by inhalation and ingestion but also through the skin at a lesser rate. Just be careful, don't breath fumes, clean up and dispose of properly and be extra diligent about washing hands and sealing the brass.

[buildswithbrian]

Fean,
so If I shop vac up the fine chips and dust from engraving should I use a special filter on the vac ?
i have read a bit about lead poisoning (old house had lead based paint) and read the dangers are typically to young children
and if ingested.
can machining brass really give off toxic fumes ??

have you read anything about the brass used in out plumbing fixtures ? or is it all lead free (nowadays) ?

Thanks,
Brian

[Deleted]

Engraving shouldn't generate enough heat to vaporize the lead. Lead poisoning affects adults as well as children, a recent example being Flint Michigan, but is particularly damaging to the brain development of young children who have a lot going on when less than 5-6 years old. As for ingestion, just don't touch anything you don't want to contaminate, especially your face, until you've washed your hands really well using an abrasive type of garage hand cleanser. Modern plumbing fixtures are made of "lead-free" brass which is now defined as less than 0.25% lead (down from the 2-4% it used to be) or one of the newer alloys based upon silicon instead of lead.

[buildswithbrian]

Dec 15, 2018 18:53:39 GMT -5 @fean said:

Engraving shouldn't generate enough heat to vaporize the lead. Lead poisoning affects adults as well as children, a recent example being Flint Michigan, but is particularly damaging to the brain development of young children who have a lot going on when less than 5-6 years old. As for ingestion, just don't touch anything you don't want to contaminate, especially your face, until you've washed your hands really well using an abrasive type of garage hand cleanser. Modern plumbing fixtures are made of "lead-free" brass which is now defined as less than 0.25% lead (down from the 2-4% it used to be) or one of the newer alloys based upon silicon instead of lead.

All great to know, thank you.

Any input on my original question about the feeds or speeds I should be using
While profile cutting brass?

[Deleted]

Switch to a larger bit. Anything less than 1/8" is typically considered micro-machining and runout as well as chip load have very little margin for error. With a larger bit any runout or lack of rigidity becomes less critical as it's a scaling issue. Is there a reason you're using such a small bit? Bits often break because of deflection which could be from going too fast or too slow as brass work hardens and if you're babying a cut you can't form a chip (which also removes heat). If you aren't clearing the chips then they will get recut and that can break a bit too for a number of reasons. In micro-machining, high-speed tool steel bits, which flex more than carbide, will tolerate more defection and abuse before breaking.

[buildswithbrian]

Dec 18, 2018 3:01:28 GMT -5 @fean said:

Switch to a larger bit. Anything less than 1/8" is typically considered micro-machining and runout as well as chip load have very little margin for error. With a larger bit any runout or lack of rigidity becomes less critical as it's a scaling issue. Is there a reason you're using such a small bit? Bits often break because of deflection which could be from going too fast or too slow as brass work hardens and if you're babying a cut you can't form a chip (which also removes heat). If you aren't clearing the chips then they will get recut and that can break a bit too for a number of reasons. In micro-machining, high-speed tool steel bits, which flex more than carbide, will tolerate more defection and abuse before breaking.

Finished the parts the other night👍
I actually did switch and used a 1/8 o-flute spiral up cut
It worked great although
I originally wanted finer detail in the profile cut and that was
The reason for trying a smaller dia. bit.
The brass is only .065 thick

Thanks