Do you wear a mask grinding HSS tool bits?

[BWParticipant @bw]

Posted by Andrew Johnston on 28/05/2019 15:13:00:

Posted by thaiguzzi on 28/05/2019 11:07:57:

??

What bit don't you understand and I'll try and explain?

Andrew

Andrew,

I am interested in your thoughts on this.

Are you suggesting that if I want to grind a 60 degree HSS thread cutting bit from a square blank that I could use a carbide milling bit to rought it out then a final sharpen on a stone or a diamond plate ?

If that is a poor example then how about something bigger ie a  boring bar from a hss blank ? 

LINK

https://www.model-engineer.co.uk/wp-content/uploads/sites/4/images/member_albums/45510/377913.jpg

 

 

Bill

Edited By BW on 29/05/2019 06:28:19

[HopperParticipant @hopper]

Posted by Andrew Johnston on 28/05/2019 10:22:59:

If you've got a lot of metal to remove from a HSS blank it's quicker and easier to mill it first, then use the grinder to touch up and add the relief angles.

Andrew

Have to admit I have never thought of that. Does ordinary carbide tooling cut HSS without problems?

[Mike PooleParticipant @mikepoole82104]

Posted by Hopper on 29/05/2019 08:46:49:

Posted by Andrew Johnston on 28/05/2019 10:22:59:

If you've got a lot of metal to remove from a HSS blank it's quicker and easier to mill it first, then use the grinder to touch up and add the relief angles.

Andrew

Have to admit I have never thought of that. Does ordinary carbide tooling cut HSS without problems?

I read that carbide would machine HSS so had to try, it turned very easily but I have not tried milling. It would make sense to me that it mills and it sounds as though it is well tried by Andrew. I suppose it has to be given a go, could save holding hot bits of HSS in your fingers.

Mike

[Paul LousickParticipant @paullousick59116]

As a model engineer, I do very little time grinding and would be extremely unlucky to develope any type of illness. A bit different from doing it in a full time job. I do wear protective glasses and the grinder is in a well ventilated area. Most of us are retired citizens and will die of old age before we do so by grinding dust.

For rough machining of a HSS cutter I use an angle grinder with a thin blade then a grinder/belt grinder and finish with a diamond stone.

Paul.

[Blue HeelerParticipant @blueheeler]

I just looked at my two 8" bench grinders and linisher where they are mounted to an outdoor workbench under a lean too (Its hot in Australia) and the amount of grinding dust around the area is quite substantial.

How do you guys get on with your bench grinders inside your workshops? Do you get grit everywhere and on everything?

[Mike PooleParticipant @mikepoole82104]

I have a Dormer 108 drill grinder with built in diamond dresser, it has a cover built into the guard to contain the dust when dressing, guess who forgot to put it down and dressed the wheel ? It created an unbelievable amount of fine dust which was 100% aluminium oxide, fortunately my lathe and mill were not in the same room.

Mike

[Anonymous]

Posted by Hopper on 29/05/2019 08:46:49:

Does ordinary carbide tooling cut HSS without problems?

Yes, although the cutter isn't going to last for ever. Basic cutting parameters are similar to turning hardened steel, ie, high speed, shallow depth of cut and high feedrate. I don't rough by mill that often as I have a large selection of pre-used HSS blanks, so I can usually find something close to what I need. Here's a HSS blank machined on a CNC mill with a 6mm uncoated carbide endmill:

The cutter was for shaping an internal gear so I wanted an exact profile, as drawn in CAD. Milling is especially useful for grooving tools where you need to take a substantial amount off the width of the blank – it would take for ever with a grinder.

Andrew

[thaiguzziParticipant @thaiguzzi]

Posted by Andrew Johnston on 28/05/2019 15:13:00:

Posted by thaiguzzi on 28/05/2019 11:07:57:

??

What bit don't you understand and I'll try and explain?

Andrew

Fine if you have carbide milling cutters – i don't. All my milling cutters are HSS.

A linisher with an Al/Ox belt as i said earlier will do the job faster and cheaper than a mill & having to buy carbide.

Getting to the exact stuff, once finished, use the T&CG.

[Author]

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