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Forum Index : Other Stuff : Why I Hate Working With Steel
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MacGyver Guru  Joined: 12/05/2009 Location: United StatesPosts: 1329 |
That little "flower" in the right-side hole is a broken 1/4-20 tap! If it's any consolation, this is only the second time in my life I've broken off a tap. The first was when I was a kid, tapping a hole in aluminum (dry probably). This one was well lubricated and I used a #7 drill; everything was hunky-dory and then . . . . . snap! 
. . . . . Mac Nothing difficult is ever easy! Perhaps better stated in the words of Morgan Freeman, "Where there is no struggle, there is no progress!" Copeville, Texas |
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| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Mack You cant beat bad luck, the world is full of it. I have noticed that some of the cheaper taps around now are to hard and break very easily, if its not a real critical application I go one drill size larger to allow a bit of root clearance and just use your finger tips to turn the tap holder as its more sensitive as to pressure applied. All the best Bob Foolin Around |
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KarlJ Guru Joined: 19/05/2008 Location: AustraliaPosts: 1178 |
indeed,I've seen lots broken by use in cordless drills etc. I like working with roofing iron! cut in a hole for a whirlybird yesterday, made a start then found it easier to tear it around the curve as opposed to cutting it which I was having very little luck at. Luck favours the well prepared |
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Gizmo Admin Group  Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
Yeah I always tap by hand, the feel of it cutting a thread is important, every time I tried to use a electric drill I broke the tap. Roofing iron! Arghh, I just dont get that stuff. Never cuts straight, and I end up bleeding all over the place. One day I will have to find out what I'm doing wrong. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
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| MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329 |
[Quote=KarlJ]I've seen lots broken by use in cordless drills etc. Man, what a great idea; I've never tried that. (MacGyver's nose begins to grow unexplainably) No, in all honesty, I played this one by the rules; correct tap drill, 90* start, even hand pressure -- the whole bit. This was one of my "trusted" taps by the way; one I've had for over 30 years. Maybe it was trying to tell me something, eh? All joking aside, you can't go wrong buying quality tooling even though you have to pay top $. Even then, apparently, s**t happens! 
. . . . . Mac Nothing difficult is ever easy! Perhaps better stated in the words of Morgan Freeman, "Where there is no struggle, there is no progress!" Copeville, Texas |
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| isaiah Guru Joined: 25/12/2009 Location: United StatesPosts: 303 |
Well Mac the picture looks to be a broken 4 flute tap? 4 fluters break the easiest!! fact!. The tap needs to be sharp age dosen't matter. As Bob stated go one size larger in some of todays steels this is necessary. If you were to look at the tap drill call out on Caterpillar's prints you'll see they call for the next bigger. On some the standard tap drill call out will work but the hole will be loose or over size when you put your screw in. Then if you use the next size bigger it will give you a good hole. Probably for you a self tapping screw would be best or Elmer's glue.'  'URL=http://www.motherearthnews.com/Renewable-Energy/1973-11- 01/The-Plowboy-Interview.aspx>The Plowboy Interview[/URL> |
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Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333 |
Isn't that why they make starter taps, and then intermediate taps. If you are not using a starter tap then you should go 1 hole size up from the listed hole size. I always use a cordless drill with the clutch set low, lots of forwards and backwards. One thing i notice is metric threads cut far better than imperial threads and think it has a lot to do with the pitch. Pete. Sometimes it just works |
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| MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329 |
Downwind Hi, Pete. I was using a starter tap and had drilled the hole deep enough to allow the tap to travel all the way through the opening. I used a #7 drill bit and at the time thought #6 might be easier, but I didn't want a sloppy fit, cause this was to be a set screw to hold a hub squarely on a shaft. Sometimes, if it's really critical, I'll chase a first-cut thread with a bottoming tap just to make sure there are no burrs. I didn't make it that far this time!
. . . . Mac Nothing difficult is ever easy! Perhaps better stated in the words of Morgan Freeman, "Where there is no struggle, there is no progress!" Copeville, Texas |
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Bryan1 Guru Joined: 22/02/2006 Location: AustraliaPosts: 1344 |
With small taps it's always a given you'll break one in a critical job, now get this with my home built cnc I have done a heap of M3, M4 and M5 tapped holes. I did manage to break one tap and it was the M5 tap that broke. My M3 and M4 taps have lasted me over 10 years but for some reason the rare M5 taps always seem to break. Even my real small BA taps down to 14BA have never broken and they are DAMN small taps. One handy lubricating fluid I use is an old product called 'magic tap'. It's perfect for any material except Ali and I'm not sure if one can buy it anymore. To stop a tap seizing in Ali try and use some kero as the lubricant, it does work a treat. I guess it all comes down to the brand of tap you buy, go the cheap route and break a tap. Most of my discrete taps are old school British made 50 years ago and they are still good for my lifetime. There is one guarantee anyone trying to copy my gear will have fun working out what thread is in that hole..... Cheers Bryan |
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| MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329 |
[Quote=Bryan1]To stop a tap seizing in Ali try and use some kero as the lubricant, it does work a treat. Thanks for the tip. I always use petroleum jelly; it sticks to the tap and cleans up easy. Hey, that reminds me of a joke. What is the German word for Vaseline? Weinerschleider!
. . . . . . Mac Nothing difficult is ever easy! Perhaps better stated in the words of Morgan Freeman, "Where there is no struggle, there is no progress!" Copeville, Texas |
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| grub Senior Member  Joined: 27/11/2007 Location: AustraliaPosts: 169 |
I was taught that soap is used as a lube with ali. |
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| Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333 |
Hi Mac, My German is a little rusty and was wondering what KY was in German. Slipenschlider?? Pete. Sometimes it just works |
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