milling a keyway (talk to me like I'm an idiot)

[Pete.]

I would say as a newbie if you try to cut that keyway with a 3/8" slot drill it'll come out a good few thou oversize. The one I did this week I milled with a 6mm cutter then plunged 5/16" cutter in one end to depth and cut the two sides in one pass.

If you're gonna cut your first keyway cut it narrow and then widen both sides to your finished size so 5/16 or 8mm cutter then move left then right a bit to cut each side equally. Take care not to climb cut around the slot or you'll get a nasty surprise.

If you got a DRO it'll be a whole lot easier.

 

[knighty]

www.cutwel.co.uk looks good... but it's a minefield for a noob like me

can anyone link me to what I need? 8mm end mill which will plunge too and as collet to hold it

my Bridgeport is r8 erm... thing.... yeah the r8 thing I forgot the name of


EDIT: p.s. yes mill has DRO :-)

 

[ukracer]

www.cutwel.co.uk looks good... but it's a minefield for a noob like me

can anyone link me to what I need? 8mm end mill which will plunge too and as collet to hold it

my Bridgeport is r8 erm... thing.... yeah the r8 thing I forgot the name of


EDIT: p.s. yes mill has DRO :-)

What collet holder do you have?

 

[waddycall]

Remember to lock the Y(?) axis when making the cut.

 

[addjunkie]

Remember 90% of a milling job is set up, if its not set up correctly, no matter which tool you choose, itll be pants.
This would work. https://www.cutwel.co.uk/milling-to...erhard-hss-short-length-slot-drill-esh57-yg-1

But I prefer the 3 or 4 fluted ones further down the page.

as for collets show us what collet holder you have. Or youd need single collets in R8 threaded for what ever draw bar you have.

R8 Collets - Round - Metric Sizes - Arc Euro Trade

R8 Round Collets: 2mm to 18mm diameter with 7/16” UNF drawbar thread. (Imperial sizes also available)

www.arceurotrade.co.uk

or these if the tools have the bit ground out for the grub screw. Weldon shank.

R8 End Mill Holders - Arc Euro Trade

End Mill Holders with R8 shank: designed to hold milling cutters with a flat on the shank. Met: 6mm, 10mm, 12mm & 16mm - Imp: 3/8", 1/2" & 5/8".

www.arceurotrade.co.uk

 

[sako243]

Ha ha no, I use a broach.

You disappoint me

 

[Hood]

You disappoint me

You are one of many

 

[MattF]

I'm ok on the pulley end, it's the shaft I'm doing

You could use the same technique on a shaft.

 

[knighty]

this is the draw bar thread... all my unf stuff is buried and I haven't really worked with that stuff since I was a little kid helping my dad so I'm no expert to spot it... but looks about right for the standard 7/16 unf to me?

I was sure I had collets, but if I have I can't find them (just looked)

what's better, collets or end mill holders with the grub screws?

what about..

R8 End Mill Holders - Arc Euro Trade

End Mill Holders with R8 shank: designed to hold milling cutters with a flat on the shank. Met: 6mm, 10mm, 12mm & 16mm - Imp: 1/4", 3/8", 1/2" & 5/8".

www.arceurotrade.co.uk

plus

8mm 3 Flute Uncoated Premium Superhard HSS Standard Length Slot Drill - ESH573 (YG-1)

The YG-1 ESH573 series Premium HSS Milling Cutter has 3 flutes and a weldon shank. These end mills range in diameter from 2-32mm. The Super Hardened Premium HSS Substrate provides exceptional value and tool life in general machining conditions.

www.cutwel.co.uk

8mm 4 Flute Uncoated Premium Superhard HSS End Mill - ESH595/6 (YG-1)

The YG-1 ESH595/6 series Premium HSS Milling Cutter has 4 flutes and a weldon shank. These length end mills range in diameter from 2-32mm. The Super Hardened Premium HSS Substrate provides exceptional value and tool life in general machining conditions.

www.cutwel.co.uk

I'll get 2 of each and see how I go?

 

[knighty]

here's the covers off and shaft in motion, it's the closest one / one to the left when camera turns

both bearings slipping on shaft now, it's the belts keeping it lined up

also, yes I know it's a duplex chain on triples sprockets... last time I put a new chain on it was all I could get that day.... it was a single chain before I upgraded to tripple so duplex is ok (for now)


EDIT: ignore the noise, there was a guy steam cleaning 10ft away from me

 

[ukracer]

Collet is around 7 quid Inc vat.

Less stick out than an endmill holder so me personally I would get a couple of collets to fit what end mills you are buying.

 

[knighty]

I'd rip that all out and put a worm box in.

can't go with a worm drive, there's too much weight/momentum in the final drive, used to have a similar machine and that always killed worm drives... about 40rpm at the end, I plan to build a new machine from scratch... but other things getting in the way

do the end mills with the flat for the grub screw fit in the collet ok?

 

[Hopefuldave]

I have always struggled with "broaching" internal keyways in pulleys on repair jobs.

What is my other option?

Pulley held in the lathe chuck/on faceplate, parting blade (with attention to rake etc.) on its side in the toolpost so it can reach into the pulley bore and shimmed to centre height, back n forth until your arm gets tired cranking the carriage*, taking a couple of thou" each pass by adjusting the cross-slide, I've done quite a few like that, no slotter (yet...)

Dave H. (the other one)

*power feed would be good *if* you can run it without the spindle turning - some can, some can't - can on my Holbrook, on others it might mean pulling the pin for backgear but not actually engaging backgear?

 

[ukracer]

What collet style do you have?

He doesn't by the sound of it. As he listed an r8 mill holder I assume he has a bridgeport with no collets or cutter holders but an r8 quill.

 

[addjunkie]

I prefer a collet to the one with the grub screw. Mill cutters fit with or with out the bit ground out.

 

[premmington]

Pulley held in the lathe chuck/on faceplate, parting blade (with attention to rake etc.) on its side in the toolpost so it can reach into the pulley bore and shimmed to centre height, back n forth until your arm gets tired cranking the carriage*, taking a couple of thou" each pass by adjusting the cross-slide, I've done quite a few like that, no slotter (yet...)

Dave H. (the other one)

*power feed would be good *if* you can run it without the spindle turning - some can, some can't - can on my Holbrook, on others it might mean pulling the pin for backgear but not actually engaging backgear?

Quote from previous massage I posted...

"Don't talk to me about "keyways".

Cutting slots into shafts is easy - it is the pulley that caused me problems over Xmas.

Repair job - broaching cutter broke - had to mount pulley in lathe and scrap out the slot using the powerfeed on tool holder - I had no other option - took me hours! "

 

[knighty]

What collet style do you have?

none :-o

I'll need some anyway, so up for buying it kit