How to remove burrs created from tapping aluminum?

[seanmoore]

Hi everyone,

Want to preface this question by stating I am not a machinist. I am a commercial photographer as well as a woodworker, so I have tools but none that are specific to machining metal.

I have a custom cut piece of 1/4" thick 6061 aluminum plate with a series of small holes (sized for a 1/4-20 tap) cut into it that will be utilized as a laptop plate for photography.

I have a basic tap set, and have started tapping the holes using the tap in a cordless drill. There are 100+ holes needing to be tapped so a drill is more efficient than a hand tap. The tap leaves a small burr on the front and back side of the aluminum plate.

What is the best way to remove this burr. I can hand file them down but that takes too long. I tried using a 5 sided countersink, the kind used in woodworking, but that didnt work. Any ideas would be greatly appreciated!

 

[boslab]

Countersink the holes before tapping works fine
Mark
Welcome btw, hope it works out

 

[EMTech]

There are countersinks made for metal.

 

[plastikdreams]

If you use the countersink in your drill do it at a very slow speed, push hard and quick.

 

[Rudd]

I get best results from a zero flute countersink - the ones with the hole through them. Use WD40 as a cutting lube. You're probably still going to need to hit it with a file lightly.

And what Plastikdreams said.

 

[Gordon Heaton]

You can also use the countersink on the backside, just don't go as deep. If you try a few I think you'll find you don't need to do any post-tapping touch-up.

 

[Conrad Hoffman]

As above. Also, when you countersink a tapped hole you raise an additional burr. When you tap a hole that's already been countersunk, you get nice perfect threads with no burr that matters.

 

[IninefingersI]

Use a rosebud. Drill #7, rosebud, tap.

 

[MichaelP]

Noga countersink tool will do it easily and quickly:
https://youtu.be/Qs9JUPz0q0A

Noga Ng1200 Rotodrive Countersink: Deburring Cutters: Amazon.com: Industrial & Scientific

 

[52 Ford]

McMaster Carr

Fluteless countersink. $10. Use WD-40 as lubricant for aluminum.

Sent using Morse code on - .- .--. .- - .- .-.. -.-

 

[Trueturning]

Hi everyone,

Want to preface this question by stating I am not a machinist. I am a commercial photographer as well as a woodworker, so I have tools but none that are specific to machining metal.

I have a custom cut piece of 1/4" thick 6061 aluminum plate with a series of small holes (sized for a 1/4-20 tap) cut into it that will be utilized as a laptop plate for photography.

I have a basic tap set, and have started tapping the holes using the tap in a cordless drill. There are 100+ holes needing to be tapped so a drill is more efficient than a hand tap. The tap leaves a small burr on the front and back side of the aluminum plate.

What is the best way to remove this burr. I can hand file them down but that takes too long. I tried using a 5 sided countersink, the kind used in woodworking, but that didnt work. Any ideas would be greatly appreciated!

Well countersinking is part of the process for a good tapped hole. The closer to any verified and standard technique is always best. When tapping merely using good sharp taps are considerations as are good center drill and drills also.

Using curing oil on the process especially the tap decreases a good bit of burr on where the thread enters the workpiece. Too another thing is to note the different kinds of taps available. Two flute taps which might be dull do leave more burrs. They have their purpose really.

You know if you do not like how something looks or feels then you can fix it up and change it up better. That is craftsmanship and attention to detail. That is engrained behavior for us and it serves us well as long as we observe and act on such things. We are responsible.

The fact that it is two flutes it means that one turn there are two cutting surfaces in action. Using a four flute tap means that one turn of the tap it breaks the chip in four places and lessens cutting pressure.

Some will simply take a proper angle countersink and gently debut the hole by hand or setting up a drill press or a Bridgeport to just kiss the countersink again. Use the same degree countersink when chasing the edge of the hole and then chase the tapped hole by hand tapping four flute being what I like to use.

This will look good. It is amazing what some cutting oil can do actually.