Need help with countersinks

[Roy Bennett]

I've tried single flute countersinks, 8 flute countersinks, and those combo pilot hole/countersinks, but I still get ragged or worse, oval countersinks.
I'm also having problems controlling the depth to achieve the correct diameter.

Any words of wisdom on this elementary skill problem:confused:

[Peter Pedisich]

Roy,

For countersinking and pilot holes for flat head screws I've had god luck with Timberline (by Amana) carbide c-sink bits like this:
http://www.amanatool.com/timberline/boring/608_110.htm

As far as countersinks w/o pilot holes I'm still searching for one that does not chatter...

Good Luck,

Pete

[tod evans]

roy, here`s what i use;.02 tod
http://www.sawmillcreek.org/attachment.php?attachmentid=43701&d=1154378237

[Bruce Page]

Roy, try c'sinking before you drill.

[Al Willits]

I have my best luck with a very slow drill speed.


Al

[pat warner]

Any words of wisdom on this elementary skill problem:confused:
_____________________________

Not trivial. Lots of things come into play, min. requirements:
1) Drill Head must be well secured to post
2) Table must be well secured to post
3) And work must be well secured (metal, wood far less so).

Key: Countersink cannot clog and must be on its own pilot arbor for max quality. V= or < 500RPM in wood, also depends on feed rate, diameter, sharpness and many other variables.

Countersik design: Ford or 3 or 4 flute garden variety, on-shear, new and HSS will give you best chance of perfect countersinks. Tricky subject if your demands are perfection.

[Frankie Hunt]

Roy, try c'sinking before you drill.

I also suggest you countersink before drilling the hole.

I use this type, except mine is not coated. As you drill with them, and the cutting edge goes into the wood, it filles up with chips/sawdust so that it self limits the depth you can drill. They work well.

http://www.woodcraft.com/family.aspx?FamilyID=798

[Randy Meijer]

Are you using a hand held drill or a drill press??

[Roy Bennett]

Thanks for all the responses. I will definately try lower speed.

Bruce & Frankie - How do you control the depth when countersinking before drilling the passage hole? CS diameter needs to be a hair greater than the fastener diameter.

Randy - I use a drill press whenever possible

[Jim Tobias]

Roy,
I tried several types until I finally bought a set of counter sinks combos from Fuller. They are high quality (in my opinion) and do not slip. They also cut evenly and stay sharp.
http://www.wlfuller.com/

Jim

[Alan DuBoff]

I use this one from Lee Valley, works excellent.

(clicky image)

http://www.leevalley.com/images/icon/woodworking/44j2101c.jpg
(http://www.leevalley.com/wood/page.aspx?c=2&p=41012&cat=1,180,42240,42281&ap=1)

[Bruce Page]

Thanks for all the responses. I will definately try lower speed.

Bruce & Frankie - How do you control the depth when countersinking before drilling the passage hole? CS diameter needs to be a hair greater than the fastener diameter.

Randy - I use a drill press whenever possible
Roy, assuming you’re using a drill press with an adjustment screw to control the depth, just turn the screw you are c’sinking for upside down and place it into the countersunk hole and check. The head should be 1/64 to 1/32 below the surface.
Try practicing on some scrap, I think you will be pleased with the results.

[Frankie Hunt]

Bruce & Frankie - How do you control the depth when countersinking before drilling the passage hole? CS diameter needs to be a hair greater than the fastener diameter.

The countersink that I use, and posted a link to, will self limit its depth. Once the cutting flutes go below the surface they will fill up with sawdust and it will go no futher. This depth will be perfect for a plug. If I need to do a shallow countersink (when not using plugs) then I just eyeball it or use the drill press depending upon the precision that I want. Using the proper diameter countersink bit, it is rather easy to just eyeball it. I use the 3/8" bit that I posted a link to. You don't want to use the 3/4" bit and try to use only part of its tip to get a proper countersink. (When countersinking a small head screw, such as a drywall screw).

[Randy Meijer]

I do very little flat work; but when I need to countersink some screws, I use an old but very sharp 8 flute CS chucked in my dad's hand powered brace. I'm guessing that a slower speed will help if you have a sharp tool.

As to the oval holes, I would think that clamping the work to your DP table would eliminate that problem. Maybe reducing the speed will help with that problem, too??:D