[SixOfOne]

I am going to have a lot of tapping to do on my build and want it to go well, lol.. Tall order I know..

I am looking for guides and found these.

drilling:
Big Gator Tools V-DrillGuide Metric Size Portable Drilling Guide - Amazon.com
Big Gator Tools V-DrillGuide Standard Size Portable Drilling Guide - Amazon.com
tapping:
Hand Tap Guide Standard V-Tap - Amazon.com
Metric Hand Tap Guide V-Tap Big Gator Tools - Amazon.com

I will have a bunch of holes to tap in the ends of 8020, and a boat load of holes to drill and tap in 6061.

I could also use some guidance in the tapping dept..
Some of my threaded holes will not be drilled with an exit point so I need special taps, I think they are called "bottom taps". Do they work just the same as standard taps (when used by hand). I have a standard tap set, should I start the bottom tap holes with them first? The bottom taps just don't look very easy to start.

Any suggestions as to where I can get them (without blowing my machine budget on tools to make the machine, lol). Every time I tell the wife I need more tools to build the machine she just replies "With all the crap out there, you don't have insert tool name here already?"

[Bob La Londe]

"boat load of holes" - That just sounds wrong. LOL.

Floor standing drill press and tapping head. Spiral point for thru holes, and spiral flute for blind holes. Set your clutch for each type, and when the clutch slips throw the tap away. Trying to get, "just one more hole," will break your heart. The spiral point will cut easier AND take more abuse.

For each tap size take a new one and set the clutch so it just barely doesn't slip on your maximum depth hole for the material type. Then write it down in a little machining notes binder you should already have in your shop for reference charts. Note size, type of tap, and material. That way whenever you put in a tap, even a used one, you can set the clutch for it.

[SixOfOne]

"boat load of holes" - That just sounds wrong. LOL.

very very wrong...

Well the 6061 that I have to do (guess it will be about 48 holes) might fit on the bigger of my 2 bench drill presses but the 8020 I need to do the ends of is 68" long..

Just before I start the tapping I'm going to ask in another post "how do you remove one end of a broken tap from 6061 and the other end from a concrete wall" lol

[Bob La Londe]

I think you are going to have to hand tap the ends of those long pieces. Sad to say. You might be able to make some type of simple guide just to do the ends of those. If you keep the tap straight its less likely to break, but a broken tap sucks no matter what. A few times in aluminum plate I have been able to punch a broken tap out and heli-coil back to size, but its better to not break any taps. I have not worked with 80/20 metal, so take anything there with a grain of salt, but I would certainly chase any untapped end holes with a proper size drill bit first.

P.S. I have used a cordless drill with the screwdriver clutch set for "hand" tapping with machine taps. Only spiral point though. NEVER with a hand tap. Your mileage will vary.

[DonFrambach]

I don't know for sure but suspect that the "drilling guide" and "tapping guide" have slightly different holes sizes.

BTW, I am a real big fan of tapping guides. I got a slightly different one than you specified from LittleMachineShop.com. Here's a link: Tapping Block, OMW - LittleMachineShop.com

Here's a photo (of the bottom of the guide):


Note the small relief's in the photo. Those work real well to provide clearance for material removed by the tap. Must say that I've tapped several hundred holes with the guide and have yet to break a tap. Before the guide, I routinely broke taps.

[SixOfOne]

I don't know for sure but suspect that the "drilling guide" and "tapping guide" have slightly different holes sizes.

This is exactly what I assumed but never seen them to be sure.

I think I will try and figure out a way to get the 48 holes drilled with the drill press. The drilling and tapping guides do look extremely helpful if you don't have a choice but to do it by hand. I have snapped a few taps over the years, not an experience I would like to re-visit.

[RicknBeachcrest]

I used the taping guide you listed to tap the ends of my 8020.
Hand Tap Guide Standard V-Tap - Amazon.com

It worked real good. I found that when hand taping you need to back the tap out and clean it out often. You can tell when it starts to get loaded up by the resistance you will feel. If not, you will break a tap and then the fun really begins.

[FandZ]

I'd highly recommend this tapping wrench for hand tapping. T-Handle Tap Ratchet Wrench It's solid and takes away any play between the tap wrench and the tap.

I tapped the ends of my 80/20 without a guide but would have used one if I had one. They came out straight enough to use for my stepper mounts.

[etard]

I almost bought that tap wrench, I was wondering if it was any good.

I have seen guys make hand tapping guides with old drill presses.

That block looks easy enough to make yourself for nearly free.

[mindmapper1]

Three reasons taps break are, not following 1 turn forward 2/3 back to release the cut materials and secondly not using an appropriate lubricant, using a tap wrench which is too big/heavy for the size tap being used.
Oh and fourthly being too heavy handed! Treat them gently

[DonFrambach]

Another reason taps can break is if the tap goes off at an angle relative to the hole. This is why tapping guides can be very helpful.

[FandZ]

To the OP,

I've just ordered some T-slot extrusions from automation4less as part of an expansion that I'm currently doing to my cnc machine. I spoke to them on the phone and they do tap on request. They are tapping 8 holes for me for for a little over 8 dollars. I've ordered plenty from them over the years and their cuts have always been clean, square, and pretty accurate in length. Prices have been good too.

automation for industry: Inch (15 Series) Extrusions & Accessories, Inch Extrusions (15 Series)

- Chris