Thursday, May 25, 2017

If You Regularly Tap Stuff, You Need a Tapmatic

I have been using a Tapmatic for tapping aluminum, steel, and acetal in my drill press for some months.  It is the second most expensive tool that I have ever bought, and worth every penny.

What is Tapping?

If you are not familiar with a tap or tapping, let me give some explanation: a tap is a tool for cutting threads into a hard material, usually metal.

Hand tapping involves putting the tap into a tap wrench:
You drill a hole just slightly smaller than the threaded hole's smallest diameter (from inside thread to its opposite), put the tap into the hole, and slowly turn it clockwise (unless you are making a left hand threaded hole with a lefthanded tap).  You turn it slowly, with some tapping oil, because taps are very brittle.  This is because to make steel very hard, and thus appropriate for cutting holes, you treat it so it becomes both hard and brittle.  (This is a crystal structure issue that I don't want to try and explain.)

Hand tapping is slow and anyone who has done it for long has broken a few taps.  Removing the part of the broken tap still in the workpiece is often too hard to justify the effort, unless it is a Porsche engine block.  Another problem with hand tapping is that it is very hard to get a threaded hole exactly perpendicular to the surface.  (Make it a round surface as I have done in the past, and it seems impossible.)

A way to solve the perpendicular problem is put the tap in the chuck of a drill press, lower the handle, and turn the chuck by hand.  This gives nice perpendicular holes and usually does not break taps.  Why not just turn on the drill press?  Drill presses turn one direction; going down at a low speed will tap threads.  When you release the handle it comes back and either removes the threads, and/or breaks the tap.  There are tapping drill presses with a reverse switch but these are expensive.  

If you need to tap holes in a production setting, hand tapping, even in a drill press, makes no sense.

Tapmatic's Solution

Tapmatic is an Idaho company that invented a gadget that goes into the chuck of your drill.  You set the drill press speed so low that you will wonder why 200 rpm exists.  It is for turning enormous drills, like a 1 3/4" diameter monster that I used to use as the first step before boring a hole to an exact size in acetal on the lathe.  Thre, you want torque not speed.  

The tap goes into the bottom of the Tapmatic.  

Turn on the drill press, and down you go.  Once the threads on the tap start cutting into the material, it starts to turn itself down.  When you are as deep as you want, you release the handle.  When the Tapmatic figures out you want to go up, it reverses direction of the tap and backs it out of the now threaded hole.  (Full screen the video.)

video
It may not be real obvious in this video what is happening, but the tap is threading the hole going down, eventually pulling the Tapmatic down with it as the threads on the tap engage the threads in the hole.  Then when I release the handle, it reverses direction.  I am making two passes here because it seems to give superior fit to the bolt when I insert it later.  That may be the result of the tap I am using; there are standards for how close a fit a tap will produce. (I may need a different closeness standard.)

Like all labor-saving devices, do not expect to open the box and be mass producing threaded holes in the first five minutes.  I struggled at first to get that long extension arm in place.  This arm has to run into a stop, a piece of metal that needs to attach to the drill press, either on the drill press vise, the table, or the frame of the press.  In my case, I drilled a couple holes in the cast iron drill press vise.  Note, 1/4" aluminum will get bent pretty quickly under impact.  (That's why hand or arm is not going to substitute for the stop.)  I am currently using a 1/2" thick piece of steel rod for my stop.  Think carefully how you are going to attach this before you get started.

There is a torque adjustment that is specific to tap size, material type, and drill press speed.  There is no magic formula for this.  You learn by trying.  The Rx50 comes with a 1/2" straight arbor that fits in my 5/8" drill press chuck.  The shank is a Morse taper where it goes into the head, allowing you to fit it to many different devices.

I have discovered that acetal, in spite of being much softer than aluminum, is hard to tap because it produces big gummy strings.  My fix was to go up one drill size from what the tap chart suggests for tapping plastic.  Now the Tapmatic works quickly and easily for tapping 1/2"-13 holes in acetal.

1/4"-20 in aluminum is a breeze.  To my surprise, 1/4"-20 in cold rolled steel was only a little harder.  You are supposed to chamfer the hole before tapping; this makes it easier for the tap to find its way to the center.  (The tap is in a rubber collet that tolerates a small amount of error.)  My experience so far is that if the tap has a sharp end (unlike a bottoming tap, which has a flat bottom) and you are pretty well located in the hole, the chamfer is not really required.  (That is what happened in the video above.)    If you are not perfectly centered, the first few turns of the tap will create a lazy man's chamfer, release the handle and try again.  By the third try. everything will tap just fine.  (Someone at Tapmatic is probably crying as they read this.)

I am using spiral flute taps so far and they do a wonderful job of evacuating material from the hole as they go down.  The straight flute taps you will find in your DIY store's basic tap kit really don't work so well.  I have really enjoyed using drill-and-tap combos that have the right diameter drill at the front, then the tap afterwards.  Unfortunately, they seem to break a bit too easily and they aren't long enough for me to drill and tap both sides of these aluminum sleeves at the same time.  But the Tapmatic makes the extra time spent tapping not so bad.

To buy a Tapmatic.  Depending on the size of taps you will use, you need to buy a collet to fit it.
Pre- and post-sales support has been wonderful.

Made in USA Stickers

I just ordered a roll of 500 to affix to ScopeRoller products.  I had briefly experimented with using the CNC mill to mill this into the metal, but that's more time than it is worth.

Tuesday, May 23, 2017

Epigenetics Spreading

I mentioned a few weeks ago about epigenetics, the claim that your children can inherit your traumatic experiences.  This Lamarckianism for (or at least from, SJWs) is spreading rapidly through the culture.  A friend returned from a class about helping Christians overcome porn addiction spouting this.  This is especially upsetting to me because it takes away one's responsibility for passing on bad patterns to your kids, and your responsibility for thoughtlessly following bad patterns in which you were raised.

It just occurred to me another reason this epigenetics nonsense is false: a woman is born with all her egg cells.  Aside from the trauma of radiation, egg cell genetics are not going to change.   At most, genetic changes would have to come from the fresh production of sperm cells.

Monday, May 22, 2017

Astrophotography

Added some more Sun pictures, aurorae, and enhanced some of the other pictures using GIMP.

Religion of Peace or Lutheran Extremists?

5/22/17 BBC:
Andy was in the arena's foyer waiting for his wife and daughter when he was thrown to the ground by the force of the explosion.
He told BBC 5 live the scene was "like something out of a war film".
"When I get up and look round, there's just bodies everywhere. I reckon 20-30 bodies. I can't say if some of them were dead but they looked dead.
"They were covered in blood and were really seriously hurt. The first thing I did was I ran into the arena trying to find my family." He found his family, who were safe, but said there were "kids and teenagers just lying there screaming".
Some reports say suicide nail bomb. Amazing how progressives insist these attacks have nothing to do with Islam.

Most Implausible Excuse Ever

Police arrived at the apartment in the Hamptons at Tampa Palms complex Friday evening after 18-year-old Devon Arthurs told police he killed his roommates Jeremy Himmelman, 22, and Andrew Oneschuk, 18, according to a Tampa Police report. Arthurs said all of them shared neo-Nazi beliefs but he later converted to Islam and killed the roommates because they disrespected his faith, the report states.
When they arrived at the apartment, police found Brandon Russell, standing just outside the door, "crying and visibly upset." Russell, wearing U.S. Army camouflage, had just returned to the apartment from National Guard duties.

I Do Not Feel So Bad About My Carbon Footprint Now

On Friday, the Obama’s jetted into Tuscany on a private – not a commercial – planeescorted into a small Florentine airport by six additional military jets, according to Italian state television. Footage of the landing has been broadcasting across Italy all weekend....

In just his trip back and forth to Italy, for his presentation and his vacation, Barack Obama has emitted more than 16 metric tons of carbon – just shy of what an average American emits in a yearAdd to that the motorcade, the internal travel in Italy, and, of course, the villa, and Obama and his wife have easily emitted more carbon in one single week than most Americans will in 2017.
Last week, Obama implored those same Americans – and their compatriots across Europe – to cut down on their carbon emissions in order to draw global warming to a standstill.
I'll take the global warming alarmism seriously when their cheerleaders do.