Anyone use a tapping guide?

[crazyal]

Not quite welding but it's metal working. I've been making a number of 1/4" round aluminum discs that need to be tapped in the very center. They are slightly smaller than 2" in diameter and have a 1/4-20 hole in the center. What I've been doing is clamping the aluminum to my drill press drilling the hole for the 1/4" tap and then tapping the hole without moving the aluminum. After the hole is tapped I then use a hole saw to cut the outside. I remove the 1/4" drill bit from the hole saw and have a grade 8 1/4" bolt without a head screwed into the hole that can slide in the hole for the pilot bit.

The only problem is that tapping the hole exactly straight without a guide isn't working as well as I would like. Has anyone used something like the Big Gator Tap guide? It looks like it's small enough to fit under the chuck allowing me not to have to unclamp the aluminum. If it's more of a gimmick and I would be better off with one of the self alignment tapping guides that would require me to at least swivel the drill press table out for access?

 

[kennyd]

I have used the Gator tap guild, and the drill guides too, they are OK if freehanding.

But, I use this on my mill, the spring loaded point will index into the tap itself, or the tap handles to hold it straight while getting it started.

https://www.amazon.com/Brown-Sharpe...ocphy=9007826&hvtargid=pla-492709878688&psc=1

 

[WranglerX]

Put tap in drill press and hand rotate and feed pressure.. After clamping disk to drill press table...

Dale

 

[RNeumann]

Put tap in drill press and hand rotate and feed pressure.. After clamping disk to drill press table...

Dale

Exactly my thought......although the OP doesn’t get a fancy new tool out of it! Haha

 

[jmc]

Combination drill-taps are common- essentially, the tap has a short drill on its tip. You would have to run it slower than plain drilling since, once the tap section engages, it will suck the combo in quickly.

Secondly, can you make a stepped pilot that stays with the hole saw? 1/4 diameter section in the holesaw with a stepped down diameter protruding, barely smaller than the tap drill diameter.

Might be worth your trouble if you have a lot of them.

 

[crazyal]

The Brown&Sharp tap guide looks interesting. How strong is the spring on the centering pin?

Turning the drill press by hand is not that easy. With a smaller tap I'm worried would loose the touch needed to keep from snapping it.

Right now to drill with the hole saw I have the drill press extended pretty far so I have plenty of room to hand tap the hole. My drill press isn't as tight as it once was so I would be worried that a stepped drill might snap.

 

[downsizingnow48]

If doing more than one or two holes I make a guide, if possible out of the same material you are tapping. In the guide, drill a hole a bit larger than the tap. In this case a 25/64 hole for a 3/8 tap. Clamp both together in the vise. Works perfect.

 

[s219]

Put tap in drill press and hand rotate and feed pressure.. After clamping disk to drill press table...

Dale

Yep, I've done this many times myself.

 

[WranglerX]

In my past life (work world) I cleaned about 200 6/32 screw holes clogged with paint with a tap in battery drill and never broke tap or damaged hole.... You have to understand processes and develop skills....

If quill on drill press is to hard to turn, remove the belt....

Dale

 

[Industrial Toys]

Why aren't those drill bit/tap combos more common? I didn't know they even existed. No more looking up tap drill sizes! And then not having the EXACT numbered or lettered bit.