NEED MM THREAD SIZE PLEZ

Larry$ said:
An M6 x 1 Translated: M for metric, 6 for the nominal diameter in mm, 1 for the thread pitch (1mm crest to crest) Tap drill size is = to the nominal diameter minus the thread pitch (6-1=5mm, find the drill closest if you don't have metric drills. That is a very common size, similar to 1/4" Imperial but won't interchange. Many configurations of taps are available. Easiest to use by hand is a taper tap, next is a plug tap. A bottoming tap should only be used after one of the others as it is almost impossible to start straight by hand in a drilled hole.
It sounds like you have little experience with tap & die use. Watch some videos before you try it. Tapping fluid helps but even almost any oil will work better than nothing. No fluids are used on cast iron. Go easy and back the tap out often to clear the chips and keep it from breaking. It is all too easy to break small taps. Probably worth practicing on some similar metal before the good part. Be very careful to start straight. Taps are hard and brittle!
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just read a drill/tap chart that sez a 7/32 drill would work for the 6.0x1m tap....thats a hair under a 1/4 ..sound right??
 
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riversidedan said:
just read a drill/tap chart that sez a 7/32 drill would work for the 6.0x1m tap....thats a hair under a 1/4 ..sound right??
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That's a pretty darn thick hair ! 10x a RCH !
 
cathead said:
I just checked my new 110 piece metric tap set and there are three pitches in 6mm.

1x6MM
.75x6MM
.8x6MM
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6mmx1 is standard, and 6mmx.75 is fine. .8 is an unusual size but lots of variations do exist.
 
A direct translation would be meaningless. M6x1 is as common in metric T&D sets as 1/4-20 is in imperial. The translation would be (roughly)15/64x25.4 TPI. Like I said, meaningless. The actual size is 0.236 vs 0.250(1/4). It is just a whisker smaller than a 1/4-20. There is was an imperial size, now obsolete, that was very close, Nr 14 at 0.242 by 24 TPI. That size has fallen by the wayside way back when, around WW2, so shouldn't even be considered unless you're into restoring old machinery. Just look for a M6x1 tap or die and get on with the project.

In the long run, learning metric sizes is easier than learning imperial/American sizes. The source of your projects will determine which is better. Learning the ins and outs of thread cutting is more important than which system to use. Taps and dies are cheap, knowledge and skill is priceless.

.
 
As we can see by looking @ The Rosetta Stone, You need a lot of drill bits to do tapping correctly. The best solution I've found is buying they typical 115 pc. set. Fractional, #, letter. Get a decent set, Mine is a Cleveland, seems decent I've had it a long time. There are enough sizes that I don't need metric bits of tapping. I made the mistake of buying a cheap set of metric by .5mm. poor quality and never the correct size needed for tapping.

If you do much tapping, sooner or later you will break a tap. I tried a tap extractor. Sort of works but often doesn't. Left hand drills will often work on broken bolts but will need to be carbide for taps. You have to be very careful as they start to make contact or they will chip. To get out a broken tap or bolt, if you can, put it on the mill and cut a flat in it with a carbide end mill. A hardware store carbide masonry bit can be re-ground as a left hand tip and used to back broken bolts and sometimes taps out. If it is a valuable part, take to a shop with an EDM.
 
mmcmdl said:
That's a pretty darn thick hair ! 10x a RCH !
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thatx for the helpful answer
Larry$ said:
As we can see by looking @ The Rosetta Stone, You need a lot of drill bits to do tapping correctly. The best solution I've found is buying they typical 115 pc. set. Fractional, #, letter. Get a decent set, Mine is a Cleveland, seems decent I've had it a long time. There are enough sizes that I don't need metric bits of tapping. I made the mistake of buying a cheap set of metric by .5mm. poor quality and never the correct size needed for tapping.

If you do much tapping, sooner or later you will break a tap. I tried a tap extractor. Sort of works but often doesn't. Left hand drills will often work on broken bolts but will need to be carbide for taps. You have to be very careful as they start to make contact or they will chip. To get out a broken tap or bolt, if you can, put it on the mill and cut a flat in it with a carbide end mill. A hardware store carbide masonry bit can be re-ground as a left hand tip and used to back broken bolts and sometimes taps out. If it is a valuable part, take to a shop with an EDM.
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already broke a 5-40 off in the piece so got a drill/tap combo thats worked out great, the other 7/32 tapered tap has held up as well.
 
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