How to machine recess/grooves on faces

[yobbo89]

what tool should i be using to do such on the face side, i tried to use a parting tool but that thing is not good at doing light cuts, it's either go or not go with that and a whole lot of noise, i tried the tool in the image. i shaved a little bit of relief on the bottom side but it's not enough, my groove needs to be 3mm deep, i'm at 1.5 mm atm

 

[T Bredehoft]

Use a high speed tool (HHS). Start out with it like a parting tool then relieve the outboard side to fit inside the radius.

 

[Downunder Bob]

What material are you machining, Do you really need a carbide bit? if you can grind a HSS tool it's quite easy to get the side clearance you need. Draw the circle full size and using a dia line as the top face of your cutting tool you will see where you need to grind away for side clearance. Creating such a tool with carbides would require carbide grinding wheels. If you have them, fine go ahead and grind, but many hobbyists don't have them. In which case you will have to use HSS, I'm assuming you can grind HSS.

 

[yobbo89]

do you have a diagram. hss tools are new to me on the lathe, i have 1 blank ,all my other stuff is mostly carbide, is a trepanning tool is what i'm after ?

 

[ddickey]

You'll want to grind a trepanning tool. Although your groove is not very deep.

 

[yobbo89]

What material are you machining, Do you really need a carbide bit? if you can grind a HSS tool it's quite easy to get the side clearance you need. Draw the circle full size and using a dia line as the top face of your cutting tool you will see where you need to grind away for side clearance. Creating such a tool with carbides would require carbide grinding wheels. If you have them, fine go ahead and grind, but many hobbyists don't have them. In which case you will have to use HSS, I'm assuming you can grind HSS.

just aluminium, it's only a small lathe so small profile cuts are done at each pass. i actually have some more hss , i'll send a pic of what i have

 

[Downunder Bob]

do you have a diagram. hss tools are new to me on the lathe, i have 1 blank ,all my other stuff is mostly carbide, is a trepanning tool is what i'm after ?

A trepanning tool would work but only if it was the correct size for the groove you wish to make.

All you have to do is like I said draw the grove to full scale two circles inner and outer dia. then draw a diameter line across the middle this line represents the top face of your cutter the side will have to ground down to clear the two circles. Actually the inner circle should clear anyway, but it doesn't hurt to give a bit more clearance. It's the outer circle that you will need to grind some clearance on the side of the tool. To help reduce chatter you can narrow the tool down so it's no wider than say a parting off tool then just move the tool across the face to get the correct groove width.

It's probably a good time to come to terms with HSS you should learn to grind basic tools there are plenty of videos online and some members here have provide special courses. unfortunately from Adelaide to Brisbane is too far away for me pop over and show you.

Do you have a boring bar? Haver a look at the shape of the cutter on the end that is how it should look. In fact depending on what boring bar you have you may be able to use it fir this job.

Or see if any of the other Brisbane members are near enough to you to be of assistance. Good luck.

 

[yobbo89]

i'm not even sure if they are pre cut to a working profile, it looks like the big one is just cut on an angle but with no back side relief.

maybe i can get away with using the straight holder and the small hss piece, the one next to the 12mm hss full bar.

I know how to sharpen tools, drill bits ,large ones too 40mm -50 mm shanks ectt , hah! but lathe tools, woah that's new

 

[ezduzit]

As DD said, this explains it.

 

[Downunder Bob]

The video provided by DDickey above is exactly what you need to do.