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    • January 12, 2018 10:34 PM EST
    • Even though this thread is about 5 years old,  here are some Google results for spot drill vs center drill that may provide additional insight.

       

      p.s. Welcome to the forum Karl.

    • January 12, 2018 9:57 PM EST
    • You will think the drill is working fine, and within a few thou of center at the beginning of the hole, only to find it is off by more than the drills diameter on the other side.

      Oh. Gee, and here I thought it was me doing something wrong. It was the drill bit itself flexing. I never would have guessed.

    • January 12, 2018 4:32 PM EST
    • Hi Jim:

       

      My name is Karl, I'm a new member and this is my first post. I have some information related to your post and thought I would use this reply to introduce myself, comment on your post, and test my picture posting skills.

      As an introduction, I'm a long time model railroader in various scales(around 50 years worth), and always a live steam enthusiast with a distinct fondness for G scale live steam. I am also, with my wife Jenn, the owners of a small manufacturing facility and have been a machinist for far to long.

       

      I have to comment on your post about Center Drills. Although they can and are used for centering the start of a drilled hole, they are not designed nor best for that use.

       

      They are designed to be used to create a taper and a lubrication pocket for dead centers on a lathe.The taper on a centerdrill is not correct for chamfering, countersinking, or thread starting. It is intended to match the angle of the taper on the dead center. The small drill tip leaves a pocket to be packed with grease, before bringing the tailstock with the dead center up against the stock to be turned between the chuck and the dead center.

       

      These are also used for live centers, but because of the thrust bearing, no lube is required since the center turns with the material.

       

      The proper way to start a drill is with a Spot Drill. These are beefy, short flute drills usually at 90 degree tip but available in other angles. They are designed to be rigid and not wander. They use a split point for further help staring on center. Normally, you use a spot drill that is larger than you drilled hole, and you drill deep enoungh to leave a chamfer after you drill. You drill larger than the diameter not only for the chamfer, but because the best way to get a drills split point to draw to center is to have the outer edges of the drill pull in first so the drill is near center when the split point hits. On screw machines with deep hole drill features in a part, you can find out quickly how far a drill can bend in a hole if you start with a spot smaller than the diameter of you drill. You will think the drill is working fine, and within a few thou of center at the beginning of the hole, only to find it is off by more than the drills diameter on the other side.

       

      Here is my attempt at a picture of spot drills:

      With two CNC lathes, two screw machines, and many years experience Supervising high volume industrial production machine shops, I have seen and heard it all. One of the

      most common misconceptions is the topic of your helpful hint.

       

      That being said, center drills will work to start regular drills for most needs of the hobbyist. Just thought you might find the clarification useful.

       

      Thanks and happy drilling

       

      Karl

    • November 18, 2017 9:24 PM EST
    • 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... 

    • August 31, 2017 1:56 AM EDT
    • Better than dating the Colonel himself!

    • August 30, 2017 11:12 PM EDT
    • " 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

    • August 30, 2017 8:36 PM EDT
    • 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?

    • June 22, 2017 6:13 PM EDT
    • 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!

    • June 22, 2017 6:05 PM EDT
    • 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.

       

    • June 22, 2017 4:14 PM EDT
    • 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.

    • June 20, 2017 6:29 PM EDT
    • 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.

    • June 20, 2017 4:06 PM EDT
    • Would think a sharp drill would not wander so much.

      Greg

    • November 18, 2017 7:43 PM EST
    • Doug, try the words instead.

      Maybe Lowes.CA uses different #s, a little bit our common colourful language:-)

      Attended Celtic Colours festival from 2000 to 2008. 

      Drive got too long.

      They now stream some of the concerts.

      Look at the links youtube has for similar concerts.

    • November 18, 2017 7:41 PM EST
    • SKU’s are an internal number, assigned by the merchant.  May not mean anything where you’re looking. 

    • November 18, 2017 7:24 PM EST
    • Typed in both the sku # and then the model # (from Don's link) into the Lowes.ca  search field

       

      sku = reprod' antique door knobs,  and the other was a corded puck light ... sometimes these corp. search services --- suck !    Only the UPC came back with, "no results" ,    on the Lowes.ca site.

      Or,

      LOL   only available in the USofA,  I guess !?

       

      doug c

    • November 18, 2017 6:59 PM EST
    • Used Amazon to locate:that UPC Ecolight 3-pack

      Lowes - https://www.lowes.com/pd/ecolight-3-Pack-3-in-Battery-Drawer-Lights/1000034697

    • November 18, 2017 6:52 PM EST
    • UPC: 755284015454

    • November 18, 2017 6:41 PM EST
    • I just looked for these and came up with nothing that looked like them.

      Lots of Christmas lights though.

      Please post a name, SKU, aisle you found them on.......

       

      Thanks!

       

    • November 18, 2017 6:24 PM EST
    • I've been needing something for lighting while I'm cutting molds for wax injection.  Found these puppies at Lowes today - three for $4.  They are LED lights & run on one AA battery.  That's scrap Romex its attached to.  I was fresh out of electrical tape, so I had to improvise with blue painters' tape.