Large Scale Central

Non vertical drilling problem?

Tools and Tips
#1

I need help solving a problem. I’m trying to drill a #52 hole in a piece of brass about 1/4" thick. I clamped the brass piece to the drill press table, and lined up the bit. As I’m drilling the bit wanders from 90 degrees vertical to a 80 to 70 degree angle. I’m using a light oil as cutting fluid, but what else am I doing wrong? My only guess is that I have too much of the drill bit shaft out of the collet, and as I cut it bends.

The other question is can I plug the hole with a brass rod, and solder together. If I do that will the new drill hole wander into the previous hole? This beginner machinist needs some help!

Craig

#2

Craig Townsend said:
I need help solving a problem. I’m trying to drill a #52 hole in a piece of brass about 1/4" thick. I clamped the brass piece to the drill press table, and lined up the bit. As I’m drilling the bit wanders from 90 degrees vertical to a 80 to 70 degree angle. I’m using a light oil as cutting fluid, but what else am I doing wrong? My only guess is that I have too much of the drill bit shaft out of the collet, and as I cut it bends. The other question is can I plug the hole with a brass rod, and solder together. If I do that will the new drill hole wander into the previous hole? This beginner machinist needs some help! Craig

Craig,

First of all, use a #1 center drill (.0468 dia. X .125 body dia.) to start the hole. Don’t depend on a prick punch mark. This is a small drill (.063), so you need to push the drill as far into the collet as feasibly possible. You are only going through 1/4 inch thick stock, so you only need slightly more than that amount showing out of the collect. Better yet, only have about an 1/8 showing to go part way. Drill it dry. No oil. You will be “peck drilling”. In other words start the #52 drill into the center drilled hole and cut maybe .020 to .030 deep and pull the drill out . Clear the chips and start the drill again. Go another .020-.030 and back off again. You will get a nice straight hole that way. Every hole I ever drill starts with a center drill. I don’t do it any other way.

As to your other question about plugging the hole: you CAN plug the hole and if you peck drill as I suggested, the drill should NOT follow the old hole. Remember this: Center drill and then choke the drill up as short as possible. Peck drill and do it DRY. You’ll be good to go. I have been a machinist/die sinker for over 50 years. You have probably seen some of my machining projects posted on LSC.

#3

Good advice…Nay! EXCELLENT advice.

#4

Would think a sharp drill would not wander so much.

Greg

#5

Thanks for the info. As I suspected, I had way too much of the drill bit out of the collet. And yes these are pretty new drill bits. Off to fire up the resistance soldering unit and solder in a rod.

I’m still learning how to use brass. It certainly takes a bit more thought than plastic in terms of drilling and cutting. Doing just a little bit of metal working highlights how useful a small milling machine would be.

#6

So I was able to salvage one of the brass parts by soldering in a replacement rod, and redrilling the hole, but I ended up tossing the piece because when I went to solder in a hinge, the combination of solder, my lack of soldering skills, and my lack of drilling skills made the whole thing into a giant mess of solder.

I’m trying to solder and build a small hinge piece for my snow plow, and this is my first attempt at using my resistance soldering set up. Definitely a learning curve for soldering like this. And I think it will also help now that I have a foot petal switch too.

Thanks for the tips about drilling. I went out and bought my self a set of center drills.

#7

Craig Townsend said:

Thanks for the tips about drilling. I went out and bought my self a set of center drills.

Nice step forward. The proper tools always increase our skills and success.

#8

Thanks Gary for all the tips here and in your build logs. My wish list is growing of tools to find, including a center drill finder, and a larger x/y table for my bigger drill press. I can see why the tooling ends up costing more than the machines!

#9

Greg Elmassian said:

Would think a sharp drill would not wander so much.

Greg

Were drilling Brass here Greg so I guessing you have never dated a Colonels daughter?

#10

" Rooster " said:

Greg Elmassian said:

Would think a sharp drill would not wander so much.

Greg

Were drilling Brass here Greg so I guessing you have never dated a Colonels daughter?

Damn Rooster, I spit half my beer out through my nose reading that(http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-foot-in-mouth.gif)

#11

Better than dating the Colonel himself!

#12

As a young PFC, I got pulled over outside Ft. Monmouth NJ in a Military Sedan with just me and a Visiting Generals daughter. They called the General to verify her ID, and then my CO to verify why I was driving a Military sedan in Civies! And then the MPs showed up. She stepped in and showed her ID and dropped the Generals name and 3 Stars on them. Things changed in a hurry. She wanted to take a moonlight walk on the beach, and every one said to go for it. We drove to Sandy Hook, and , and, and … When we got back to base the guards were waiting for us. Along with the OD and we had an escort to the Visiting Officers Quarters. The next morning, my CO, had a stern talk about protocol, and then sent me out again, with the Generals daughter for the day (she had requested me again ), on escort duty. She wanted to go to the Board Walk on Cony Island. Daddy had provided us with $50 for the day. Some days in the army were better then others…