drilling an axle

[dutchtreat]

I'm thinking of drilling my axle and would like to know how much space between the holes? I have a good 3/4 drill bit and have checked some axles at local shows and there were 3/4" and 1" holes(not on the same axle). Like to stick with the 3/4" and only drill between the spring pirch bolts--the center section only.Thanks

[Unkl Ian]

I think Magnum makes theirs with 17 holes,so around that many should be safe.
Space them evenly and see what you get.

[Tman]

Visually, the gaps between the holes should be at LEAST the same distance as the diameter of the bit....my thoughts. Just dont go crazy. Stock axles are way thinner in the web than a Magnum. I think I used a 1" holesaw and spaced em 1.5" apart.

[The37Kid]

Once you deside on the spacing center punch all the holes and drill a starter hole with a center drill, and work your way up to the 3/4 bit. I'd clamp it in a drill press rather than use a hand drill. Buy some cutting oil and a brush.

[tommy]

http://fototime.com/{2BAC9D2B-63FC-4901-88BA-8626B21DAE46}/picture.JPG
.
I used a 7/8" hole saw. actually 2. It was a lot easier than drilling each hole 3 times with large drill bits. Nice slow speed with plenty of oil.

[Eyeball]

I used a 3/4" hole saw as well. I spaced the holes 3/4" apart. Use plenty of oil an just take your time.

I used a 1" hole saw with I think 2" spacing. Ended up with 13 holes. I used a drillpress and set it to it's slowest speed. Lots of oil and the hole saw is still good. Thaught I would ruin it but it's still sharp.
Clark

[38Chevy454]

Well, in aerospace they have a rule that there is a 2 x diameter distance between hole edges. That means there is actually a 3 x diameter for the hole spacing. So in your example with 3/4 inch holes, the centers would be on 2.25 inch. That would give 1.5 inches between holes. However, for aerospace they have to be very concerned about fatigue and higher stresses than your axle will receive. A big factor is how you clean up the hole edges, they should be deburred and blended smooth without any sharp corners or gouges. A full radius would be best, but that is a lot of extra work, just make sure they have a good chamfer minimum.

So here is my recommendation. Leave at least 1 x diameter between the hole edges, or 2 x diameter for hole centers. I would prefer a little more, but the actual stresses in the axle web are very low, so it is OK to have them closer than the aerospace rule. The main stresses in an I-beam axle are handled by the upper and lower flanges, not the center web. The web is really just a spacer to hold the flanges apart. It does have some stresses, but not very much in relation to the flanges.

I would recommend a hole saw instead of the drill bit, less total metal removal and time required.

[stoggie]

Cooles axle I have ever seen used a 1" hole in the center and then smaller ones moving outward.
Had an awesome look.

[Thirtycoup]

great topic, nice post there dutchtreat

[atch]

how's the best way to debur? radius? i'm thinking that any way you do it that's "by hand" will probably result in something less than consistent.

[wingnutz]

Has anyone tried a 1" Uni-Bit...?

Seems to me that if you drill out to a 7/8" hole the remainder of the Uni-Bit would form the desired chamfer edge...!

Mark

[stoggie]

I wondered this too. But would you only get the chamfer on one side?? Do you still need to touch the other side with the uni-bit?? http://www.jalopyjournal.com/ubbthreads/images/graemlins/confused.gif

[Unkl Ian]

You can use a Countersink to champher the holes.
Run it at a slow rpm.
Just make sure the countersink is small enough in diameter to get in there.

[atch]

unkl,

i agree that a countersink will debur well. will it also leave a 45 degree "edge" with two "sharp" corners on each face now instead of one? if so is this a structural problem?

i'd really like to be able to get about a 1/16" radius all the way around every hole. sort of like what you get with a router in wood. can that be done? consistently?

tommy,

it looks like you've got a nice smoothed off edge on your holes. is that true or does the pic lie? how did you do that?

[Morrisman]

You could use a bunch of them little 'flap wheels' with the emery paper on them, and just waggle them around in the hole using your electric drill. That'd give a nice smooth finish and a bit of a radius to each hole. Probably best to take the initial corner off using a standard countersink.

Here's a pic of the Sherpa beam axle I drilled for my rod, but that one was 3/4" thick! Took me several days, and I eventually never used it, after all that work http://www.jalopyjournal.com/ubbthreads/images/graemlins/confused.gif

[wingnutz]

[ QUOTE ]
Cooles axle I have ever seen used a 1" hole in the center and then smaller ones moving outward.
Had an awesome look.

[/ QUOTE ]

Just saw an axle done this way and he used a Unibit...! He flipped it over and cleaned up the edges using the same bit..., looks great!

Just have to remember which ring to stop at for the regressive hole sizes.. http://www.jalopyjournal.com/ubbthreads/images/graemlins/tongue.gif!

Mark

[JOECOOL]

Most of the uni-bits I've used were not thick enough on each step to go thru the axle . Therefore you may have to go at each side. Just a thought.

[stoggie]

Last night I pulled one of the tool box and thought the same thing. twice the work 3 times the coolness. That would also solve the problem of controling the chamfer on both sides....
Creative hi-jacking huh...actually this was a great post. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[willowbilly3]

I have never drilled an axle but intend to soon. I appreciate the holesaw idea. I have tried to use 1 inch and larger bits in the drill press and just couldn't get it slow enough. I think the slowest speed on mine is 220 and it needs to be about 150 I think. I bent the shank on my 1 3/8 bit because of too high of speed at 220 rpm.
How fast are you guys spinning the hole saw?
Also I like the diminishing size idea. I was thinking about making ovals by drilling 2 holes almost touching and grinding out the rest.
If you had access to a water jet you could come up with some really cool stuff like writing.

[SimonSez]

This subject came up a while ago here and someone suggested getting a ball bearing (bigger than the hole in the axle) and hammering it on the hole to stress relieve the edge.

I guess it would also make a bit of a radius on the edge of the hole.

You could probably also use the ball end of a ball pein hammer and hit it with another hammer.

[tommy]

[ QUOTE ]
unkl,

i agree that a countersink will debur well. will it also leave a 45 degree "edge" with two "sharp" corners on each face now instead of one? if so is this a structural problem?

i'd really like to be able to get about a 1/16" radius all the way around every hole. sort of like what you get with a router in wood. can that be done? consistently?

tommy,

it looks like you've got a nice smoothed off edge on your holes. is that true or does the pic lie? how did you do that?

[/ QUOTE ]

A big rat tail file to knock the edge down. The nice thing about hand work is you can get the look you want without the "oh shit I went to far" syndrome.

FWIW. I did the unsplit wish bone with an antique 1/2" drill motor that will spin your ass around when the holesaw hangs up! An old aluminum Black & Decker drill with a screw in pipe handle for extra leverage. I couldn't fiqure out a way to use a drill press. I did the outside (money side) first letting the pilot bit give me the location to drill the other side from inside.

[atch]

although dutch started this thread, i thank all of you for the info. had he not asked now i would have soon.

i'm givin' this one five stars.

[29EHV8]

I drill every axle I drop.
I've done a few with 1 1/8" holes.They look kill,kinda like lets go fuckin racin baby!
I space my centerpunch marks three inches apart.
I've tryed the hammer hittin hammer bit but the axle is curved inside the beam so it aint consistent.I hand file all the holes.
I use holesaws on 220 in the drill press.I use lots of oil.I'm still using the same holesaw,done lots of axles with it.It aint no cheap discount toolstore one though http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif
Got no pics right now.
This is a damn good post.....Shiny

[Mutt]

Racecar - done with a 1 1/8 holesaw on a mill.

Mutt

[wingnutz]

Looks like a Harmonica...! http://www.jalopyjournal.com/ubbthreads/images/graemlins/shocked.gif Does it Whistle...? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

Now that's an agressive modification...!
http://www.jalopyjournal.com/ubbthreads/images/graemlins/shocked.gif
Mark

[Steve]

mutt no offense but I think ya drilled yer holes to close together. with the right amount of flexing I could see some of those gaps breaking

[Mutt]

[ QUOTE ]
mutt no offense but I think ya drilled yer holes to close together. with the right amount of flexing I could see some of those gaps breaking

[/ QUOTE ]

No offense taken - it's been run on this dragster for a couple of years without a problem. Some of the gaps look thinner than they are in the picture.

Mutt

[Steve]

the dragster looks bitchin. I was thinking for a road car that has to deal with shitty bumpy roads.

[Unkl Ian]

For the street,you would want to leave some of the webbing around the holes.

3/4" - 7/8" diameter seeems to be safe

[Mutt]

I was incorrect on the hole size too - it's 1 1/8 http://www.jalopyjournal.com/ubbthreads/images/graemlins/confused.gif I believe there's a minimum of 1/8" web between holes...

Getting older sucks! http://www.jalopyjournal.com/ubbthreads/images/graemlins/blush.gif

Mutt

[wingnutz]

The dragster looks great...!

For the street I'd be less aggressive with the hole size and amount of holes.

The front of that dragster doesn't take half the abuse that a heavier road car takes on the public pot holed roads!!! http://www.jalopyjournal.com/ubbthreads/images/graemlins/shocked.gif

Mark

[Greezy]

On my axle I used a 7/8" hole saw, the holes are on 2" centers, 17 holes. I then used the flapper wheels to knock the edges off, and give them a slight chamfer. I recommend using a drill press if you got one, set it at lowest speed like said before and use lots of oil.

[willowbilly3]

You drop your own axles 29EHV8? Maybe you could give us the low down on that sometime.
BTW nice holeshot in the picture of the old slingshot.

[Flat Ernie]

[ QUOTE ]
You drop your own axles 29EHV8?

[/ QUOTE ]

Doesn't everybody? C'mon man, this is The HAMB!

Check out this thread in the tech-o-matic:

Titus' Dropping Axles Tech (http://www.jalopyjournal.com/ubbthreads/showflat.php?Cat=&Number=240434&page=1&view=collap sed&sb=5&o=&fpart=1)

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif