Drilling stainless firewall *HELP*

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Drilling stainless firewall *HELP*

Postby Havithuvi » Mon Dec 24, 2018 7:18 am

Hi Everyone,

I am having a hard time getting my firewall match drilled. I am using Avery cobalt #40 drill bits with "off the shelf" Home Depot cutting oil. Further, I'm using my cordless drill on very low speed with quite a bit of pressure. After monkeying with this for well over an hour, I have one hole and about 6-7 trashed drill bits.

My question for those who have already completed this step.....

Exactly what brand, type of drill bit did you use?
Exactly what type of cutting oil did you use?

Any help on this would be fantastic!


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Re: Drilling stainless firewall *HELP*

Postby bullojm1 » Wed Dec 26, 2018 10:11 am

What sort of drill are you using? I don't recall anything special about drilling SS.....my drill bits are from Avery, and I used BoeLube , however, any cutting oil should work? My thought is you might be turning the drill bit too fast. A slower speed drill with light pressure applied to the bit (let the bit due the cutting!) might be a solution for you.
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Re: Drilling stainless firewall *HELP*

Postby captain_john » Fri Dec 28, 2018 6:03 am

Like Mike said, speed and feed are both the key. You need to find that sweet spot. Boelube works great, but also try Parpolive gold dishwashing liquid as a lubricant. A friend of mine who is a plumber taught me that trick. Plumbers drill stainless steel sinks all the time. Using a unibit works very well also. Try one of those.

Hole punches work very well also. If you have large holes like the one for the heater or wire pass-throughs a Greenlee hole punch is going to be on your wishlist. You will know when you are done working with stainless because the bleeding stops! LOL good luck!

:mrgreen: CJ
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Re: Drilling stainless firewall *HELP*

Postby sibriggs » Mon Jan 07, 2019 10:03 am

Slow the speed down. Drill at a very slow RPM. Too fast and it won't cut.
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