Best Porting Bit for Aluminum?

I have several carbide bits for my 4A 1/4” shank die grinder. One is a very high quality cobalt bit. Neither chew aluminum as they do steel! It looks like some helical designs might be better suited for Aluminum?

So what do you guys use to chew aluminum if not these?

Google Killer Carbide.
Raved about by the racers on the A-body side, Pittsburgracer, Newbomb Turk and others.
Go over to the a side and search "porting burrs".
(I'd copy a paste some info, but I don't know how.)
You will see an a-bodies only review by Rat Bastid. Same guy as Newbomb Turk.

Killer Carbide has a good rep, but the burrs you already have can work a lot better if they weren't loading up.... There are a lot of products that will stop or at least slow the accumulation... WD-40 is far from the best but everyone already has some.. Better is Tap Magic for Aluminum, Old school but effective is Bee's wax.... Cheap but effective is just grab a plastic milk crate, grind the plastic first then grind aluminum.. A little plastic, a little aluminum...

And this cut and paste might be helpful...

If you’ve been using a carbide burr to remove material from aluminum, chances are good that you’ve got some aluminum buildup on the burr itself. This can decrease the burr’s effectiveness and make it harder to use, so it is essential to clean it off regularly.


The good news is that it is easy to do – all you need is some muriatic acid or sodium hydroxide.

• First, you’ll need to gather your materials.
• In addition to the acid and hydroxide, you’ll need a glass or plastic container to hold the mixture, gloves to protect your hands, and eye protection.
• Once you have everything, mix equal parts of the acid and hydroxide in the container.
• Then drop your carbide burr into the mixture and let it sit for a few minutes.
• After a few minutes, remove the carbide burr from the mixture.
• And rinse it off with water.
• You should see the aluminum buildup come right off. If necessary, repeat the process until all the aluminum is removed.
• Finally, dry off the carbide burr.
• Store it in a safe place until you’re ready to use it again.

I find that dipping the grinding burr in some wire feed welding anti spatter tip dip keeps it from clogging up.

I dip my burrs in ATF. They don't clog, lubes and somewhat cleanses all at the same time. High temp, high pressure wash in parts washer once done. My last project was gasket matching, porting my tunnel ram.

Moparfiend said:

I have several carbide bits for my 4A 1/4” shank die grinder. One is a very high quality cobalt bit. Neither chew aluminum as they do steel! It looks like some helical designs might be better suited for Aluminum?

So what do you guys use to chew aluminum if not these?

View attachment 1652794

Click to expand...

To answer your question, the only Aluminum bit I see is the one at the bottom. All of the others are for Iron, and clog up faster. You can use them, but must clean the flutes often. For me, the aluminum ones jump around to much, and I carefully use the carbide bits made for iron and pay attention to the loading.

as noted by 4 or so members already

Of any of the carbide style tips, I've used a combination of both styles
(style doesn't matter, "much" except specific to get in a certain place/spot)
all need some sort of lubricant so they don't clog, (I too use wd-40)
especially with aluminum...

I like my old Mikita 1/4" high speed electric peanut grinder
it's 30+ years old, I'm on my second one now
I tried the air style straight & 90*, doesn't do the same level of job
I do use an air chuck 1/4" (usually a 90*) peanut grinder
to do with the drums/rolls/sanding, it does well

A good 'stiff stainless brush' helps clean them too, then lube them again
did probably 200 (?) combined cylinder heads & intakes, for my personal motors
over the past almost 50 years, it's/neither brush or wd-40 never/ever failed me

my old buddy Mark Lowe (RIP) professional head porter, did the same
if it was good for him, it was good for me...

opinions will vary, vastly
that's mine

carry on

I used to have to grind ungodly amounts of aluminum at work and the best short term fix is to get a
block of wax and continually touch the burr to the wax while working. If you are going to be working
non-stop, get a one gallon coolant spray mister that uses compressed air to cool tools in a machine shop
setting and use a hose clamp to mount it to the die grinder. Use Kool Mist #77 and water to keep the
burr cool and nothing will stick to it. I use wax to lube a band saw blade while cutting aluminum so it
doesn't stick!

You need a wide flute aluminum burr and a can of WD-40. The burrs you have are for steel and cast iron.