Trickey hole

Hi folks, I have a questions that you may be able to help me out with. Please look at this photo:

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This is one of the suspension mounting points on my race car. The holes in those ears are ~.4760 and I need them to be .5 and with as little "oblonging" of the hole as possible. As you can see there is not a lot of room in there to get a drill. The space between the ears is 2.5", the space between the right ear and the frame is 2", and the space between the left ear and the outside frame is 4" (this is larger to facilitate inserting the bolt).

I've thought about possibly a right angle drill attachment and a stubby 1/2" drill bit with a small shank. However, the two attachments that I looked at were to large to fit in that 4" space. What other options are there? I "might" be able to get a 90degree air grinder w/ a grinder/rasp in the 4" space but that would only get the left side ear...

Any ideas would be appreciated!

Wayne

Reply to
wrace
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Maybe you can find or make a short reamer.

Reply to
Tom Gardner

How about a real right angle air drill & a .5 inch center drill possibly cut in half? That combo with the drill I have would easily fit in the 4 inch area.

Reply to
Stephen Young

I would purchase two half inch reamers, and cut one so that it will fit in and do the first hole, you will be able to do it by hand. You will have to machine the end of the reamer square after you cut it off short so that you can get on it with a wrench.

The other reamer will be cut a bit longer so that it will reach to the bottom to hit the other hole. Thirty thou is not too much to take off with a chucking reamer.

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Reply to
jim rozen

Cut a hole in the floor above and tehn weld it back afterwards......

Reply to
Mike

For $9.15 you could cut a 4" section out of a 1/2" diameter round file (with an abrasive disk) and turn it back & forth with a vice grips... it isn't like you have to take out a lot of material or do a bunch of holes. McMaster-Carr also has a 1/2" carbide ball end burr for $10.75 that would be about 3.5" total length in my 90 degree die grinder; but since the ball is round you wouldn't need to go straight at the hole? David

Reply to
David Courtney

||wrace wrote: ||> Hi folks, ||> I have a questions that you may be able to help me out with. Please look at ||> this photo: ||>

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||> ||> This is one of the suspension mounting points on my race car. The holes in ||> those ears are ~.4760 and I need them to be .5 and with as little ||> "oblonging" of the hole as possible. As you can see there is not a lot of ||> room in there to get a drill. The space between the ears is 2.5", the space ||> between the right ear and the frame is 2", and the space between the left ||> ear and the outside frame is 4" (this is larger to facilitate inserting the ||> bolt). ||> ||> I've thought about possibly a right angle drill attachment and a stubby 1/2" ||> drill bit with a small shank. However, the two attachments that I looked at ||> were to large to fit in that 4" space. What other options are there? I ||> "might" be able to get a 90degree air grinder w/ a grinder/rasp in the 4" ||> space but that would only get the left side ear... ||> ||> Any ideas would be appreciated! ||> ||> Wayne ||> ||> ||How about a real right angle air drill & a .5 inch center drill possibly ||cut in half? That combo with the drill I have would easily fit in the 4 ||inch area.

Don't forget it has to drill the far tab as well, which means a drill bit of over 2.5" added to the drill/chuck depth. I would suggest a right angle drill attachment. I think the cheapo one I have from HF is about 3" from the back to the tip of the chuck. Then use a shortened bit for the first hole. For the 2nd hole, insert a longer drill through the first hole, then work the right-angle attachment in and over the end of the drill. Tighten, and drill. You may have to fiddle with the length of the 2nd drill to figure out the max length you can get away with. You may even need to grind a shallower angle on the cutting edges, to make it slightly more compact.

Rex in Fort Worth

Reply to
Rex B

How thick is the metal? If it's around 16 gauge or less I'd use a knockout punch. It'll be tough to center on the hole but otherwise it should fit nicely in the small space and give you a good clean hole. McMaster Carr has one, item number 34685A27.

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Search for the item number.

Best Regards, Keith Marshall snipped-for-privacy@progressivelogic.com

"I'm not grown up enough to be so old!"

Reply to
Keith Marshall

Maybe a hand expansion reamer. Or perhaps a die grinder or even an air ratchet to drive a multi-fluted conical reamer. MSC calls them step drills, around page

186 in BigBook, several styles.

mj

Reply to
michael

Wayne,

You need something like:

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That particular one is metric so max = 12mm (you need 12.7mm) but they are available in Imperial sizes with max = 1/2"

Drive it with an angle drill

Andrew Mawson Bromley, Kent, UK

Reply to
Andrew Mawson

You might also be able to press the file piece through the hole with a clamp (sorta like a broach) ?

Dave

Reply to
Dave Keith

That would be my solution, too... driven by the following (or similar)

90deg angle drill motor:

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Do NOT use a drill.... unless you *really* want to create a mess....

Reply to
Gene Kearns

Can't you just rebush the new suspension to take the original bolt size? Chances are there's just a steel dowel inside a rubber bushing which will press out and then turn a new dowel up on the lathe.

Dave Baker - Puma Race Engines

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I'm not at all sure why women like men. We're argumentative, childish, unsociable and extremely unappealing naked. I'm quite grateful they do though.

Reply to
Dave Baker

Maybe you could modify a hand (threading) tap or a milling cutter to act like a reamer. Maybe use a tap that has an OD of 1/2" first to tap a 1/2" thread and then grind the thread off a slightly larger tap down to smooth 1/2" and use it as a crude mini reamer. Alternatively grind a square to fit a socket wrench on the end of a 1/2" milling cutter and a taper on the nose and use it in the same way. Can't think of any other, reasonably accurate ways.

Mark K.

Reply to
Mark K.

On Thu, 08 Apr 2004 18:22:41 GMT, "wrace" shouted from the rooftop:

After you get those holes opened up, I'd suggest you seam weld the box sections- those spot welds look pretty far apart and you'll be amazed at how much better the axle location is.

What kind of car is it- I know I've seen one from that angle...

-Carl "An honest man doesn't need a long memory"- Jesse Ventura

Reply to
Carl Byrns

After you drill the first hole, you could remove the center drill, slide a short .5 inch drill through the newly drilled hole & then chuck up the air motor to the bit to finish the second hole.

Reply to
Stephen Young

Thanks for all the input. This group is such a great resource. The car is a late model Camaro that has mostly metric fasteners (and holes) from the factory. The suspension pieces I built use QA1 3/4" rod ends w/ 3/4" to

1/2" bushings. The other end of control arm connects to a custom bracket w/ 1/2" holes.

The holes shown in the picture are metric, just a shade smaller then 1/2" . I could just use the metric bolts/holes but it is a little sloppy inside the

1/2" bushing. It bugs me to go to all this work to "tighten up" rear suspension with quality rod ends, only to induce slop with undersized bolt. Thus my concern with trying not to hog out the hole too much... possibly inducing the slop I just removed by using the correct dia. fastener.

The metal is not too thick. I think I may try the cut 1/2" file or reamer trick. I'm afraid using a drill bit in this application may just tear up the hole given they are so close in size. I'll have to pick up a 1/2" file and give it a try with some vice grips. I'll try to grind a chamfer on the end to help align it with the hole a little better.

Thanks again.

Wayne

Reply to
wrace

Use an expansion bolt in your hole....

Reply to
Kevin Beitz

The other suggestions mention a stepped drill, otherwise known as a Uni-bit. I've used one of these for years and it's been the most effective drill for sheet or thin sections. There is one model size that's 1/4" to 3/4", which I think would be the best choice for this situation. I'd probably try to adapt the Uni-bit to a ratcheting box end wrench for this location. This would give you a slow drilling cutter that will produce a clean round hole of the correct size, and if the wrench grip doesn't permit enough feed/side force, you could apply light feed pressure with a lever of some sort.

The drill could be modified by adding a nut (or a drilled section of hex stock) to the shank. An epoxy might last long enough for you to complete the

4 holes, and you could recover the Uni-bit for use in a drill for future use. Another way to adapt it would be to drill and tap the nut for a setscrew, and grind a small flat on the shank of the Uni-bit.

WB .............

Reply to
Wild Bill

If you're not doing this for a living, here is the $2 solution.

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Taper reamers are a good tool for a lot of problems with holes with poor access. These are cheap enough that you can cut them down to size and grind flats on them so you can turn them with a wrench.

Cheers,

Kelley

Reply to
Kelley Mascher

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