Home > VansAirForceForums

- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

Old 01-05-2018, 08:20 PM
dareha dareha is offline
Join Date: Sep 2016
Location: White City, Oregon
Posts: 22
Default Drill bit sharpener

A sharp drill bit makes it so much nicer and let's face it we use a lot of drill bits. Is there a good drill bit sharpener that sharpens at the correct angle for what we do? Or is it cheaper to just buy new drill bits.
Thank you.
Donated for 2017
Building RV 9A
Southern Oregon
Reply With Quote
Old 01-05-2018, 10:11 PM
RandyAB RandyAB is offline
Join Date: May 2016
Location: St Albert, Alberta, Canada
Posts: 195

A lot of people have used the Drill Doctor and have raved about it. I bought one based on the reviews and truthfully I haven't had the best of luck with it. I've only tried it on the smaller bits so perhaps results are better with the larger ones. The most common angle I believe is the 135 degree split point. For #30 and #40 bits I would by a bunch and discard them when they stop performing. YMMV
Randy P.
1st time builder
RV10 - Empennage (Started March 2017)
St. Albert, Alberta, Canada
2017 dues paid
Reserved:C-GRPY (GRumPY)
Reply With Quote
Old 01-05-2018, 10:18 PM
Zero4Zulu Zero4Zulu is offline
Join Date: Nov 2008
Location: Scio,Oregon
Posts: 201

Drill Doctors will make your drill sharp but the web will be off center and the drill bit will drill over size. Buy small drills in packages of twelve. McMaster or MSCdirect.
Steve S.
Rebuilding RV6A
Scio, OR
EAA Ch. 292
Reply With Quote
Old 01-05-2018, 11:05 PM
DNeufeld DNeufeld is offline
Join Date: Aug 2016
Location: Coeur d Alene
Posts: 54

For me it's hit and miss with the Drill Doctor for the small #40 bits. I always test drill and re-sharpen if it's oversize.

It does seem chintzy but it works OK. Worth the money IMO.
Dues paid 2017
Reply With Quote
Old 01-06-2018, 05:10 AM
Cyclone Cyclone is offline
Join Date: Dec 2014
Location: Grinnell,IA
Posts: 26
Default Drill Doctor

I had a Drill Doctor thrown in "free" with a new wire welder deal. After a couple of years I threw it in "free" on a plasma cutter trade in. My shop is a better place now.
Rv-12. Empennage done
Wings done
Fuselage done
Finish kit done
Avionics ordered

"I have enough money to last me for the rest of my life.
As long as I don't buy anything"
Reply With Quote
Old 01-06-2018, 05:53 AM
Jimd Jimd is offline
Join Date: Apr 2008
Location: Central Iowa
Posts: 287

I do a bit of hobby machining and watch my share of machinist type videos on youtube. The collective wisdom seems to suggest that no matter how you sharpen your bits, IF you are good at it and they seem better when you finish, you are always better off buying new if the size is less than 1/4" and some use a larger size minimum than that because the price point for small bits doesn't justify the time and likely imperfect bit.

Most of the experienced guys sharpen them by hand on a grinder.
RV-10 tail kit 50%
(When do I get to measure something?)

"Flying north of the Arctic Circle and back - several thousand dollars,

Doing it in an RV you built yourself - PRICELESS!"
Reply With Quote
Old 01-06-2018, 05:53 AM
tgmillso tgmillso is offline
Join Date: Nov 2012
Location: Launceston, Tasmania, Australia
Posts: 504

I built a slow build RV-7 and guess I've gone through about half a dozen cobalt #40 drills and about 4 #30 drills. If you get cobalt aircraft drills you'll never be able to justify needing a drill sharpener, let alone the frustration of not having a perfectly ground and easy to control bit. A roofer here told me that drilling steel roofing sheeting they would go through half a dozen drill bits a day, at $6 each. I told him I could get some cobalt aircraft drills for him, and because they were so cheap, he ordered 50. I saw him a few months later and asked how they were working. He was still on his first cobalt drill. I guess he's got himself a couple of lifetimes worth.
I have developed a policy of only buying cobalt bits, and when I'm no longer happy with they performance, I retire them to the tractor workshop on the farm where the mechanic can sharpen them on a grinding wheel and continue to use them on farm machinery. Knowing I can keep a bit centered and not botch a part is far more important than saving a couple of dollars on bits.
Reply With Quote
Old 01-06-2018, 07:06 AM
scard's Avatar
scard scard is offline
Join Date: Jun 2005
Location: Cedar Park, TX
Posts: 2,700

A single lip cutter grinder is way more fun, and accurate .
Scott Card
RV-9A N4822C flying 1850+hrs. / Cedar Park, TX
RV8 Building - fuselage / showplanes canopy (Done!)
Reply With Quote
Old 01-06-2018, 08:35 AM
9GT's Avatar
9GT 9GT is online now
Join Date: Jan 2010
Location: Southern Michigan
Posts: 1,250

I have one of the more pricey models of The Drill Doctor and have never been able to get a good sharpening with it, even on larger drill bits. I find that the goofy clamping fingers that hold the bit after you get it set up and positioned, tend to twist the bit out of place when you tighten it up and I ended up giving the bit a sharpened tip that was not usable. I used to be able to get good bit sharpening's by hand on a consistent basic back in the 70's when I did it daily working in a prototype job shop as a checking fixture builder, but its rare I hit it now. Buy good quality drill bits and throw the #30 and #40 bits out when they get dull. Even good quality bits are pretty cheap IMHO. I prefer to ream for final size though and seldom drill.
David C.
Howell, MI

RV-9A: Under Construction
RV-10: N959RV Completed 12/29/2013 SOLD 08/23/2016

"Donor Exempt" but donated through Dec. 2018
Reply With Quote
Old 01-06-2018, 08:53 AM
Larco Larco is offline
Join Date: Mar 2005
Location: DVT Phoenix
Posts: 937

I had the top of the line drill doctor even took it to the factory for adjustments. Then threw it away. I felt much better after hearing it hit the bottom of the dumpster! Life is better now. :-))
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -6. The time now is 09:44 AM.

The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.