[danreetz]

I have a piece of 1/2" hardened steel rod from a printer carriage, and I want to drill and tap a hole on each end of it to mount it to a frame. I have an X2 mini mill and cheap drill press at my disposal.

Are there any tricks to getting the hole centered on the end of the rod? Anything I should know?

[MrWild]

You need a dial indicator. Mount the indicater in the mill spindle and move the table while turning the indicator until it reads zero all sides.

[LeftCoastCNC]

How hard is the material? As a general rule, if you take a file to it and the file does not remove any material you are wasting your time trying to drill and tap it.

[danreetz]

I have a dial indicator and could center it in my mill -- if the piece wasn't 4 feet long. Sorry for not saying that earlier. It won't fit in my mill the with the end pointing up at the end mill.

I'll check the hardness issue.

[Med-Pac]

The easiest way would be to find a shop with a lathe. Might cost you a few bucks, but that would be the correct way to do it.

Mike

[danreetz]

Of course you're right, and if it comes to that, I will, but I am still open to any advice or suggestions.

[DareBee]

If it is through hard, no one can tap it without an EDM.

[Fixittt]

if you cannot drill and tap the rod itself, can you make some pinch clamps to mount the rod into and then mount eh pinch clamps where you need it? Or passably bore some holes where you want the bar mounted so that its a really tight press type fit? Press the bar into the bored holes with a tad bit of lock tight and it wont go anywhere. Just trying to figure out another method of skinning the cat..... with what you have.....

[ALLtra Mach]

As far as centering the hole:
Take a larger piece of material, say 1" square, and drill it through jus a bit smaller than tap drill. Then drill and ream it for a snug slip over shaft a good 1" to 1 1/2" deep. Slide it on the end of the shaft and run tap drill through into shaft. The longer you can make this slide on drill bushing the straighter it will keep you.

As for hardness of the shaft, if it is case hardened, you have several options for that. If it is thru hardened....they're right it is edm time.

[danreetz]

Aha, that was what I was looking for. Thanks.

And yes, clamps are an option, if this fails.

[Fixittt]

one suggestion, if the material is really hard. Try heating up the ends to glowing red. Then allow it to air cool. This will soften the material to allow you to hopefully drill and tap it.

EDIT
If you go with the above suggestion with the drilling and boring into a block. Remember NOT to remove, or move the machine. (I know, hard to do) but this will help insure that you are in the center of the HOLE that was drilled and bored.

[ALLtra Mach]

If you go with the above suggestion with the drilling and boring into a block. Remember NOT to remove, or move the machine. (I know, hard to do) but this will help insure that you are in the center of the HOLE that was drilled and bored.

Huh? Not really sure what you mean by this, but I've actually done this with a hand drill. Of course doing it in a machine will be more precise.

[Fixittt]

As far as centering the hole:
Take a larger piece of material, say 1" square, and drill it through jus a bit smaller than tap drill. Then drill and ream it for a snug slip over shaft a good 1" to 1 1/2" deep. Slide it on the end of the shaft and run tap drill through into shaft. The longer you can make this slide on drill bushing the straighter it will keep you.

As for hardness of the shaft, if it is case hardened, you have several options for that. If it is thru hardened....they're right it is edm time.

This is what I was refering to....

as for heating up the bar ends. You would have to use a torch.

maybe some meaning got lost somewhere

[danreetz]

Sorry, fixittt -- I read this thread before my morning coffee and misunderstood.

[warrenb]

This is what I was refering to....

as for heating up the bar ends. You would have to use a torch.

maybe some meaning got lost somewhere

I would bet that the shaft is just case hardened or chromed and that should grind (sand) off (keep it cool though). As for making a drill jig with the block, I like it. Otherwise....off to a lathe shop.

Warrenb

[keebler303]

Another option might be to counter bore the piece it will mount to slightly. You can use that hole to locate the shaft and then the screw will only be holding it in. Then you can get it close by hand to drill and tap and then use an oversize clearance hole to pass the screw through into the shaft.

Make sense?

Matt

[LeftCoastCNC]

One more option for drilling using a mill; Depending on your mill configuration, it is possible on many knee mills to rotate the head and ram so the axis of the spindle is NOT over the table. The part can be clamped to the side of the table and hang down below. It would have to be a larger knee mill to work on the end of a 4ft part... but just thought I would through out the idea.