Yes but there is are three glitch's. J&L list imperial collets, they are listed as decimal sizes like
0.472" - 0.512" which low and behold equals 12 - 13mm.Next is a good glitch, they are cheaper then the metric listed ones.
Last glitch, when you order them they come marked up 12-13 on the face.
Now whether these new imperial ones promised by various supplies follow this line, one can only wait.
I can't see a problem with tightening down to fit 1/4". You don't have to do it all the time, only to initially fit the cutter and they will go down and grip, it's not as if you are straining it past a design point.
After working for years with conventional single split collets like the R8 and 5C these are a breath of fresh air. A while ago I had to turn some stepped pins up. 12mm stock with a
11.5mm step, then hold these on the 11.5 to work on the small 12mm step left. Two operations, work all the steps with a 12mm 5C collet then bore an emergency collet out to 11.5 for the rest of the work. Result is I now have a duff collet at 11.5 that probably won't get used again.-- Regards,
John Stevenson Nottingham, England.
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