Tips & Techniques Want to share a tip or special technique you have either in the workshop or at the flying field or race track? Post it right here!

Drilling wheel hubs out?

Reply
Old 12-24-2005, 03:58 PM
  #1
wsmalley
Thread Starter
 
Join Date: Feb 2002
Location: Monterey, TN
Posts: 1,080
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Drilling wheel hubs out?

Got a new set of 5 1/2" Dubro wheels that go on 1/4" axles. Drilled them to 1/4" but they're too tight. Whats the ideal next size drill up to get them right? I don't want any excess 'slop'. Thanks, Bill
wsmalley is offline  
Reply With Quote
Old 12-24-2005, 04:57 PM
  #2
bkdavy
 
bkdavy's Avatar
 
Join Date: Sep 2004
Location: FrederickMD
Posts: 2,114
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Roll up a piece of sandpaper, put it through the hole, and rotate the wheel around the paper. You'll take off just enough to fit the axle.

Brad
bkdavy is offline  
Reply With Quote
Old 12-24-2005, 07:49 PM
  #3
the-plumber
 
Join Date: Aug 2004
Location: East Cobb County, GA
Posts: 1,390
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

In order of increasing size,
6.5mm, F, G, and 17/64".

You _might_ have the last one.

Otherwise, sand as advised above.
the-plumber is offline  
Reply With Quote
Old 12-25-2005, 08:57 AM
  #4
TLH101
 
TLH101's Avatar
 
Join Date: Dec 2001
Location: Elephant Butte, N.M.
Posts: 6,707
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Try using a prop ream in the correct size. I have found that when drilling wheels, the hole always seems to shrink just a touch after drilling. I think maybe heat build up causes it. Just drill it like you normally would, then run your prop ream through, and you will have a nice fit that does not bind or wobble.
TLH101 is offline  
Reply With Quote
Old 12-25-2005, 12:20 PM
  #5
da Rock
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,460
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

If you have a solid mount for your drill, move the wheel up and down the turning bit a couple of passes.
da Rock is offline  
Reply With Quote
Old 12-25-2005, 12:30 PM
  #6
da Rock
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,460
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

You know, I bet a bunch of you think this is overkill but.........

Years ago I lived in a big town. There were a couple of industrial supply houses. They looked to me like big NAPA stores only they sold lathes, mills, etc, and all manner of bits and machine shop supplies etc. I was trying to make my own pistons at the time and needed accurate holes. Reamers are the answer, not drills. Those supply houses sold every size imaginable. I decided to buy a couple in sizes that would help those simple tasks, like getting accurate wheel/axle holes.

Since I've never been real happy with running a drill bit into those plastic wheels, it's almost impossible to get an accurate hole, I've been happy as a fly on a pig's lips to sit and turn that "expensive" reamer by hand.

I've not looked, but I bet there is at least one internet site for reamers, real "industrial strength" ones. Mine weren't much more expensive than the drill bits you see on the wall at Home Depot or Lowes Home Improvement.
da Rock is offline  
Reply With Quote
Old 12-25-2005, 03:09 PM
  #7
wsmalley
Thread Starter
 
Join Date: Feb 2002
Location: Monterey, TN
Posts: 1,080
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Your right about the reamers. Anything, I believe, properly machined with a 'round' hole is reamed. I will check my prop reamer-hadn't thought about that! I did fiddle last nite on one with the sandpaper, and it is working-but man, is that tedious. Personally, I'm one who normally needs instant gratification! Guess I would need the 'F' reamer, I have a few letter drills in the box, wish I had a whole set.
wsmalley is offline  
Reply With Quote
Old 12-26-2005, 09:53 AM
  #8
SST
 
Join Date: Jun 2002
Location: Mt. Morris, MI
Posts: 1,151
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

The reamers Darock is talking about are sold as oversize dimentional reamers. You'll find the 1/4" range marked as .248, .249, .2495, .250 .2505 .251, .252 etc. You can find them for fractional or metric sizes. Try www.enco.com for individual pieces or whole sets.
SST is offline  
Reply With Quote
Old 12-26-2005, 01:02 PM
  #9
the-plumber
 
Join Date: Aug 2004
Location: East Cobb County, GA
Posts: 1,390
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?


Quote:
ORIGINAL: TLH101
Try using a prop ream in the correct size. I have found that when drilling wheels, the hole always seems to shrink just a touch after drilling.
Most drills aren't really sharp enough to cut the plastic precisely, and even though material is indeed removed during drilling, the plastic also deforms a bit to accomodate the drill bit, resulting in a hole that is smaller than would have been made in metal.

Try drilling and tapping UHMW (Ultra High Molecular Weight) plastic some time. No matter how many times you run a tap through the threads, the threads will be very tight when trying to run in a machine screw. BTDT. Next time I need tapped holes in UHMW I'll use threaded inserts.
the-plumber is offline  
Reply With Quote
Old 12-26-2005, 01:40 PM
  #10
wsmalley
Thread Starter
 
Join Date: Feb 2002
Location: Monterey, TN
Posts: 1,080
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Well, thanks for the tips guys. Fred: you're right about drilling that plastic! I wound up using the prop reamer and rolled up sandpaper and got a nice smooth fit. The sandpaper method took a loooong time, and quite boring, but, it was do something, or watch 'Lifetime' movies with the wife. Those are some of the most boring movies ever made! They could be used for interrogating prisoners: "Talk or you watch 3 Lifetime movies in a row!"
wsmalley is offline  
Reply With Quote
Old 12-27-2005, 03:16 PM
  #11
JPMacG
 
Join Date: Jan 2002
Location: Ivyland, PA
Posts: 2,260
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

I finally broke down and bought a set of lettered and numbered drills to add to my fractional inch drills. The extra sizes have been handy many times. They are not usually found in comsumer hardware stores - you need to get them mailorder or from an industrial supply place. Watch out for low-quality imports.
JPMacG is offline  
Reply With Quote
Old 12-27-2005, 06:10 PM
  #12
pcjohnson_ohio
 
Join Date: Apr 2002
Location: Toledo, OH
Posts: 71
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

I've drilled an oversized hole and used heat shrink tubing on the axle
Worked well
Pete
pcjohnson_ohio is offline  
Reply With Quote
Old 12-27-2005, 08:32 PM
  #13
Gollywock
 
Join Date: Sep 2002
Location: Santo, TX
Posts: 406
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Or drill it oversize and shim it with a brass tube from K&S -Jim
Gollywock is offline  
Reply With Quote
Old 12-28-2005, 11:10 AM
  #14
MinnFlyer
 
MinnFlyer's Avatar
 
Join Date: Apr 2002
Location: Willmar, MN
Posts: 28,519
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

What I will often do is to glue a piece of sandpaper to a dowel - in this case, if the hole is 1/4" you could use a 1/8" dowel (or maybe a 3/16" dowel with a shorter piece of sandpaper)

Glue one edge of the sandpaper to the dowel, then wrap it around the dowel. Put the dowel in a drill, insert it into the hole and the centrifugal force will push the sandpaper against the hole.
Attached Thumbnails
Click image for larger version

Name:	Zx71185.jpg
Views:	99
Size:	47.4 KB
ID:	376834  
MinnFlyer is offline  
Reply With Quote
Old 12-28-2005, 12:11 PM
  #15
CCRC1
 
CCRC1's Avatar
 
Join Date: Aug 2002
Location: Waldorf, MD
Posts: 1,109
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

wsmalley,
I have a suggestion you may want to look at. I am not fond of the plastic wheel running on a steel axle and bearing the load of the airplane. Every one that I have ever had like that ended up wearing prematurely. I would rather drill the wheel to accept a nylon or bronze bushing. I found some nice smaller size nylon flanged bushings from SIG, and for the larger sizes, hit your LHS in the RC car section. Most of the time bushings are replaced in RC cars with bearings so they are fairly easy to get. Finding some with an ID. of 1/4" shouldn't be to hard. You may even get lucky and find some flanged bearings with that ID.
CCRC1 is offline  
Reply With Quote
Old 12-28-2005, 06:31 PM
  #16
da Rock
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,460
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Drilling wheel hubs out?

Brass bushings?

The K&S tubing is sized so that each tube size fits rather well into the next size larger. It's quite easy to use for a fixed bearing on the axle, or fixed bearing in the wheel, or both. And since drill sizes match up as well, it's easy to create an appropriate sized hole in the wheels.

The only very slight problem I ever ran into using that tubing as wheel bearings was on a CL rat racer that lived far longer than those suckers usually do. The high nitro fuel and the way it's slopped around a rat racer must have kept the wheel (only had one) wet every time we flew it. And brass is not a good metal to use around fuel. (Which is why I'm constantly amazed that most fuel tanks still are sold with brass clunks and tubing.) And one day I noticed the tire was showing grey-green stains. It still turned great, but it was obvious the brass was reacting to the fuel baths. (Have you ever opened up a really old fuel tank and looked at the brass inside?)
da Rock is offline  
Reply With Quote
Old 10-02-2013, 09:22 AM
  #17
GoNavy
 
Join Date: Jan 2002
Location: Rib Lake, WI
Posts: 531
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I realize this thread is very old, but the advice was spot on. I used the prop reamer and got 1/4 inch.

I had used a 6.5mm drill bit, that is .2559, but the hole was still so tight you could not push the axle in.

Thanks to all.
GoNavy is offline  
Reply With Quote
Old 10-03-2013, 08:31 PM
  #18
Leroy Gardner
 
Join Date: Jun 2009
Location: Idaho
Posts: 2,177
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

An F letter bit will do it, it's used to drill holes for 1/4" rivets so you can get the rivet in them and buck um. Works great on hubs as well.

Leroy
Leroy Gardner is offline  
Reply With Quote
Old 10-19-2013, 01:01 AM
  #19
bikerbc
 
Join Date: Jan 2011
Location: SorrentoBritish Columbia, CANADA
Posts: 2,018
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

It also helps to put your wheels in the freezer for a little while first .. then I go up a size in bits .. I have a set of number bits and I use them .. Its not a big deal if there is a little bit of play as long as its not too much .. It will allow room for a bit off grease or oil .
bikerbc is offline  
Reply With Quote
Old 10-21-2013, 07:12 AM
  #20
dadragon
 
Join Date: Dec 2008
Location: pine bluffs, WY
Posts: 485
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

+ 1 bk & minnflyer
dadragon is offline  
Reply With Quote
Old 07-28-2014, 09:32 AM
  #21
Marty79
 
Join Date: Mar 2014
Posts: 29
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

You might try a 17/64 drill in a drill press turning as slowly as possible to prevent heat building up
Marty79 is offline  
Reply With Quote
Old 07-29-2014, 04:01 AM
  #22
CafeenMan
 
Join Date: Jan 2003
Location: Spring Hill, FL
Posts: 4,734
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I drill for a brass tube that fits the axle. Then I can press the tube in place and the clearance is perfect.

Generally when you need to drill holes that become bearing surfaces you're going to need number and letter drills. Fractional drills will never be the exact right size.
CafeenMan is offline  
Reply With Quote
Old 07-29-2014, 04:31 AM
  #23
sensei
 
sensei's Avatar
 
Join Date: Jul 2002
Location: SAN ANTONIO, TX
Posts: 2,630
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

F drill = close fit for a 1/4 dia axle.
H drill = free fit for a 1/4" dia. axle.

Bob
sensei is offline  
Reply With Quote
Old 08-03-2014, 06:48 AM
  #24
Villa
 
Villa's Avatar
 
Join Date: Aug 2003
Location: Wilson, NC,
Posts: 2,057
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Sometimes, if the hole just needs to be a little larger, I will use a slightly larger drill, and force it thru the hole, but in reverse direction. Sometimes this works OK.
Villa is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 02:59 AM.