Deburing advice

[atalla]

Hi all Im working on my practice pieces and have been reading a lot about deburing no more than 10% of the thickness of the work piece. I'm using a 3 flute deburing tool from Aircraft Spruce. With my drill press set at max 3050rpm i was getting a fair amount flashing on the backside on my #30 holes through my angle. I debured as lightly as i could due to the sharpness of the new tool but i noticed two things

1- The round hole no matter what i tried was turning the chamfer into a rounded triangle due to the three flutes.
I have a 6 flute which will cut down on chattering but am unsure of the angle and don't want to chance it. Is a single flute (round hole ) cutter in these sizes avail?
Iv seen the drill mounted spring loaded debur tools that do both sides at once but there pricy, only work with one size, and I haven't heard anyone here raving about them.

2- To pass the finger nail test 3 and sometimes 4 turns of the tool were needed which worried me due to the 10% rule. heres the angle with what i think are over debuted
Notice the chattering.....

I also want to ask all about a switching to a reamer. Cost? benefits? RPM ?

Thoughts? Pics of a perfect marginal and scrapped hole?

[wirejock]

Don't over think.
Thick parts will have more burrs no matter how you drill but reamers will produce less.
I call those holes over deburred. Probably ok on a thick piece but too much for a skin. Two spins with very light pressure, more on a thick part with bigger burrs. Too much pressure will make it chatter. You can barely see the chamfered edge when done.
The standard three flute is fine for deburring the gazillion holes in your plane. Some use scotch brite and just scrub the surface. You're just removing any burrs on the edge of the hole.

Yes, IMHO, you can and probably should invest in a set of single flute but more for countersinking.

Reamers are great. Cost about $9 each. Perfect round holes with almost no burrs but extra work. Speed is the same. I usually drill one or two steps small and use the reamer for final hole. #40, #30, #19, #12 and maybe 3/16", 1/4" and 3/8" will cover most jobs.

[YellowJacket RV9]

I run my drill press very slowly; will yours go slower? Recommended RPM for aluminum is under 1000 I believe. Your post got me wondering about the actual math, and I've found varying numbers, but 5500 is way above any of them. Also, I like to deburr thicker items like that either on the scotchbrite wheel or with a dremel and sanding drum. Makes super-quick work of it, and since those parts generally get primed, no worries about scuffing them up.

The deburring tool will work much better on the skins where much less pressure is needed.

Chris

[rv7charlie]

https://www.google.com/webhp?sourcei...te+deburr+tool

helps with the chatter marks. What are you using to run the deburr tool? Hand powered, or drill?

On the subject of excessive burrs, are you using backing material behind the stock? Sharp drill bits? Dull bit &/or no backing will cause the bit to push a chunk of metal out of the way instead of cutting it away at the end of the hole.

Charlie

[BobTurner]

I deburred everything with a hand tool. I found it impossible not to apply too much pressure with a drill press.

[Tom Martin]

NO drill press for deburring! as mentioned before use the hand deburring tool. One or two light turns should be enough. Do NOT debur if there are no burrs, not every hole needs to be done. Over doing this operation will cause a lot more damage then not doing anything at all. All you are trying to do is to get rid of anything that will keep the two parts from nesting snuggly together.
Lightly run your finger over the surface. If it feels smooth, leave it alone. Be careful with your fingers if you have office hands, cuts can result.

[YellowJacket RV9]

I had assumed he meant using drill press for the drilling. Definitely do not use it to deburr!

Chris

[bddalm]

Deburring should be done by hand. It only takes a couple of turns in most cases.
Check out these YouTube videos:

https://m.youtube.com/watch?v=2XOat0lT0P0

https://m.youtube.com/watch?v=wlZiYU_usu0

Hope you find these helpful.

[David Paule]

Here's how I'd deburr those holes:

1. Make a light pass down the length of the angle with a flat mill file, a fine one. That'll take off anything that sticks above the surface.

2. With the correct size reamer in a chuck, I run the reamer down into the holes by hand, turning it a half or full turn. That cleans out the hole. Note that although I leave the chuck on the drill for this, I don't connect the drill to the air hose. This is strictly by hand. The only reason for the chuck is to get some mechanical leverage on the reamer.

3. Check with fingers and repeat as needed.

This goes VERY fast and doesn't hurt the holes.

Dave

[atalla]

Originally Posted by wirejock

Reamers are great. Cost about $9 each. Perfect round holes with almost no burrs but extra work. Speed is the same. I usually drill one or two steps small and use the reamer for final hole. #40, #30, #19, #12 and maybe 3/16", 1/4" and 3/8" will cover most jobs.

Awesome Thanks

Originally Posted by YellowJacket RV9

I run my drill press very slowly; will yours go slower? Recommended RPM for aluminum is under 1000 I believe. Your post got me wondering about the actual math, and I've found varying numbers, but 5500 is way above any of them.

Chris

I was under the impression min 3600 rpm for alu as per the sioux drill 6000 for acrylics and plastic ?

Originally Posted by rv7charlie

https://www.google.com/webhp?sourcei...te+deburr+tool

helps with the chatter marks. What are you using to run the deburr tool? Hand powered, or drill?

On the subject of excessive burrs, are you using backing material behind the stock? Sharp drill bits? Dull bit &/or no backing will cause the bit to push a chunk of metal out of the way instead of cutting it away at the end of the hole.

Charlie

Hand use only, i used an oak backing while drilling using the drill press.