The Bucking Magnet Motor

[z.monkey]

Rhythm interrupted...

Snapped off a tap.  This is inevitable because there is a lot of stress on a tap.  And I was really trying to take it easy on this one.  This tap came from an Ace Hardware store.  It lasted 9 holes before it broke.  Fortunately it snapped above the hole, and I was able to unscrew it, saved the hole...

The second tap, uulgh, came from Harbor Freight.  It snapped the first time I used it.  And it snapped off in the hole.  I am hugely disappointed with the second tap.  I have to drive like ten miles to a Ace Hardware to get more taps.  Big Sigh...

[hydrocontrol]

Rhythm interrupted...

Snapped off a tap.  This is inevitable because there is a lot of stress on a tap.  And I was really trying to take it easy on this one.  This tap came from an Ace Hardware store.  It lasted 9 holes before it broke.  Fortunately it snapped above the hole, and I was able to unscrew it, saved the hole...

The second tap, uulgh, came from Harbor Freight.  It snapped the first time I used it.  And it snapped off in the hole.  I am hugely disappointed with the second tap.  I have to drive like ten miles to a Ace Hardware to get more taps.  Big Sigh...

I have drilled and tapped hundreds of holes without breakage. The major key is lubrication and a good tap. A small amount of tap oil will keep the tap from binding. In place of tap oil you can use wd-40 or even vegetable oil.

Good project and good progess.

[z.monkey]

Thanks Hydrocontrol,

On the way to the store it occurred to me that I am probably making the pilot hole a little small also.  I do have some thread cutting oil, and didn't even think to use it...

Doh!

[z.monkey]

I have snapped off another tap, and a drill bit.  My list of failed tools is getting long today...

Two holes are unusable, going with backup plan, gorilla glue...

The depth of the holes relative to the girth of the tap is a problem.  Lubrication helps, but when there are lateral stresses, like when it breaks through a hole into a angled wall, the frictional stresses are so great the tap snaps, and it is stuck like Adamantium fused with Unobtanium.  Ain't Mutha-Forkin' gonna move...

So, the Ultimate work around...  Gorilla Glue...

Just for a few parts mind you...  This is only for temporary use.  Experimental purposes only...

I may change my mounting strategy here, but really not sure where to go.  I'll try and finish this one as planned.

But it may be a kludge-a-matic-o-saurus-amongus, and it might not last long in test...

[loosecannon]

sorry to hear about your woes.

ive drilled plenty of aluminum and ive broken off more than my share of bits and taps in it.

not sure if you are trying to use the mill when threading those holes, but i find it easier to use a cordless drill to tap holes. the mill didnt give me enough time to stop or back up before the tap broke. the cordless drill gave me more control. definitely use aluminum cutting fluid also.

depending on the hole size you are using, you might think about abandoning the tapping idea, and just use sheet metal screws.
if the pre-drill is the right size, and you use a bit of bee's wax or soap on the screws, they should go right in no problem.

the concern i have now is that the gorilla glue will throw off the balance of the stator because you will have no screw in two places.
you've spent so much time making this thing very balanced it would be a shame to have it wobble now.

i hope i have posted this in time, and you havent gone past the point of no return yet.
there may be a way for you to save those holes with the drill bit/ tap in them.

because you have stuck a ferrous metal into a non-ferrous metal, you may be able to use Alum to dissolve the drill bit.
mind you i have never tried this, but i have heard of it working.

here is a little write up for jewelry, but the same concepts apply.
at least its an avenue to pursue so you dont have to give up on them.
http://www.ehow.com/how_4999647_dissolve-broken-drill-bit.html

good luck with it!
LC