grooving .028 wire over 1.2" length

I'm trying to do this one the lathe, but no matter how I grind the tool , Carbide or HSS, I cannot get a good clean cut, at any RPM. Any alternatives to traditional machining you guys can suggest?

Material is steel, probably music wire .028" dia., (pretty hard but machineable) that has a black oxide coating. I need uniform grooves, depth not important .002 or .003" is fine, just enough to get thru the coating and create crisp line.
spacing every .5mm (.02") over a distance of 1.2 inches .

Whether you do it abrasively or with a cutting tool on the lathe, try making a bushing in the tailstock which supports the wire, so it can be held between chuck collet and tailstock with only enough gap between to create the grooves. Have used this approach with very tiny PEEK and Ultem parts before with great success.

Looks like a good task for a Dremel cutoff disc attached to your toolpost ...

This is along the lines of apoc's suggestion. I modified a tool holder to have support block that had an interchangeable brass bushing. The bushing fits the OD of the stock, with the cutting bit right next to the bushing. For all intents its a travelling steady rest.

I might try dental floss charged with clover lapping compound .

Make up a two point friction guide that moves with the carriage or compound. A hollow bushing to support the work. Start at the chucked end and work out.

;-)

Are you looking to keep the color on the uncut portion?

Music wire is machinable, but not easily. You want some really good carbide, for little stuff like this i grind up old high end micro end mill shanks (3mm diam usually). But I'm not surprised when corners break down after a few cuts.

Are you sneaking it out of the collet a bit at a time? That's obligatory if you dont have a setup like zip's above.

Grinding is going to be your best bet. A handheld square nose graver watchmaker style will get you close but you won't have tremendous precision on spacing or depth without loads of fiddling.

Zipp, how does the cutting tool move independently of the support ? Does the bush bracket float on those slots? That looks like something I could use here was we do a lot of plastic rods and such .

yes I was trying to keep the color in the uncut portion, it's just "gun bluing" really so not that Robust. I was using a drilled Teflon bushing in the tail-stock drill-chuck as an OD "dead center".

Screwmachine said:

Music wire is machinable, but not easily.Grinding is going to be your best bet.

Click to expand...

well that is all true, and I did go the grinding route with my Dremel and bought a right angle head $25.+ a .007" wide wheel for ceramics $16..

Thanks Mbraddock for that, never really gave the Dremel much thought as a "hobby tool" but it appears to have it's uses beyond just de-burring

Really worked quite well, did the whole lenght in 1 shot by spinning the lathe head at fairly low speed and opposite direction of dremel wheel. Looks pretty wacky, and this really wouldn't take much force at all, but it was good enough for precision scratches on wire.
thanks to all