LocostUSA.com

Okay, so here's my problem. I have a hydraulically powered auger that attaches to my Case skid steer tractor (Bobcat). The shear pin hole diameter is 1/2" and the loaner 12" bit has a 7/8" hole. I would like to enlarge the 1/2" hole (which is slightly elongated on each edge from twisting off too soft of shear pins) to 7/8" so that I can use this new auger bit.

It's too big of a unit to get on my mill or drill press and I really don't want to take the auger apart to separate the shaft. I know regular drill bits will break off their tips, so is there a tool like an expandable reamer or something like that which will allow me to enlarge that hole?

I didn't see a "Weird Questions Forum", so if this is in the wrong place Moderators, please feel free to move it.

Thanks in advance for any helpful insight.

Tom

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Sometimes, I'm as confused as a baby in a topless bar.

My short term memory is absolutely horrible and so is my short term memory.

https://www.youtube.com/watch?v=sG16m2e4O6I

You could probably use a step reamer, the hard part is finding one.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.

Faced with a similar situation I took my bench top drill press and laid it over sideways, braced it reasonably well and drilled out the attachment points in the bucket that I was trying to fit to my tractor. I used a titanium drill bit and kept it well lubricated with cutting oil as I drilled. I drilled it slowly too so as to not bind the bit. It worked okay. I was only making the holes 1/8" larger though.

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Bill H
Winnipeg, MB, Canada

Are you convinced of the safety of modifying your equipment to use a larger shear pin? A shear pin is a mechanical fuse, they are sized to be the weak link in a system, you're talking about tripling the strength of the pin. Is the rest of the system strong enough that a 7/8" inch pin will shear before anything expensive breaks?

If i am reading you post right, you maybe able to sleeve the loaner from 7/8" to 1/2" versus drilling yours.. try http://www.mcmaster.com/

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-STu

There is no shame in defeat, so long as the spirit is unconquered

My Build Log

It's not a shear pin, but a draw pin. Super hard. There is a shear on the other end of the jack shaft that this shaft is driven by.

The thickness of the bit is only .250" and I'm afraid I'll beat up the bushing.

I don't know if the step bit will work either because of the amount force required to cut with 3 or 4 steps at the same time.

Tom

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Sometimes, I'm as confused as a baby in a topless bar.

My short term memory is absolutely horrible and so is my short term memory.

https://www.youtube.com/watch?v=sG16m2e4O6I

I'd try a step drill to get the hole round and then use a regular drill bit with just a regular hand held drill.
Kristian

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V6 in a book frame build. Now registered.
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