Drilling a perpendicular hole in drill rod material

[ngr1]

Hello, can someone please advise me of the proper technique for drilling a perpendicular hole in drill rod material or any other relatively hard material.

The drill rod is ¼” OD and I am trying to drill a hole to press fit another rod in a perpendicular manner.

I am assuming a v-block will be required and you can find the center using the block but how do you start the hole? Is there some kind of center drill that can be used before an actual drill bit?

Any help for this hobbyist would be appreciated.

Thanks… Norman

[nervis1]

Heres my advice. You need a v block (or two), a carbide center drill then a carbide drill (undersize) and if you want a press fit you'll need to ream the hole to size. I don't think a drill will be that accurate.

[ngr1]

Thanks nervis1.

Do you mean the same center drill I would use on my lathe or something else?

Norman

[Ken_Shea]

Drill rod as purchased new drills fairly easy since I think it may be annealed at that point. You will be able to drill it with a any good HSS drill, as you and Nervis one pointed out it will need to be centered drilled with a lathe center drill being ok but a spot drill being the best, you probably will not need to got to the expense of carbide at this point.
Just start slowly. As nervis1 also pointed out you cannot drill a precision hole and if that is needed it must be reamed.

[nervis1]

Yep, the same stuff. Just make sure you locate that hole where you want it. What machine are you using, drill press? Mill?

If a mill then you can edge find the center of the bar. Remember that round stock (drill rod is probably right on) is rarely exact in size, measure it first and do the edge finding with that measurement.

[Ken_Shea]

Norm I promise I won't bloat your thread past this

Dave, how you coming on the 4 axis ?

Easy,Hard,Frustrating, or going to sell it to Ken for $300

[HuFlungDung]

It can be a bear to get the hole started without wandering of the spot drill, especially when the part is steeply curved, such as is the case with small diameter rod. It takes a good solid spindle (like on a mill) to ensure a correct start.

it can help a great deal if you mill a small flat spot on the part, then spot drill it, then drill it, then ream it.

[Ken_Shea]

Norm you have enough information here so just try this on a piece of scrap, I think you will find that it will not be all that bad a job for you. If you have a mill with a DRO it will be a piece of cake, if not it will be a little bit tougher but very do-able. Once again take it slow and don't get in a hurry, think through your steps from start to finish.

Let us know, OK

[nervis1]

Ken. The 4th axis is sitting on my garage floor. I have been working so hard at the day job that I got it up on the table, rep came over and tuned the servo, set some other stuff, I ran one test cut on some foam, just some slots, holes. (Had big plans at this point of course) my buddy calls from NM and wants some foot rests made for his ATV, which are .....flat plates of course.

I lug the 4th off the table with the engine hoist, and do the job for my friend, back to work on Mon and there she still sits. Between my VMC and the trash can. Poor 4th axis.

I'll try and give her some attention next week. (Is a 4th axis female?(talk about a wierd question!))

[nervis1]

Sorry don't mean to threadjack ngr1, carry on.

[ngr1]

I like the idea of millnig a small flat spot first.

Thank You Gentlemen!

[garagefela]

Hello all,
I have had the same dilemma on a few ocasions and this is what I came up with.

I found a piece of scrap steel square bar, for this excercise lets say it was 1" square and cut to 1.5" long.

I clamped the bar to an angle plate and drilled a hole through the long end of the block, this size hole accepts the drill rod.

Now rotate the block 90 deg and drill a hole through to the existing hole, this side hole is the size that you want to be in the drill rod itself.

Now you have a handy little jig which you can hold in a vice or clamp down, simply place drill rod in the hole and drill your hole into the rod, this jig helps to stop the drill wandering all over the place.

The exact position of the holes in the jig block do not matter as long as the block is rotated and not turned around when you make it, this ensures the dimension from the edge of the block to the hole centers is identical.

Certainly not the best or most accurate way of doing the job but it all depends on your required accuracy.

I hope this helps. Cheers M