Order of work for small item?

[Martin King 2Participant @martinking2]

Hi All,

I need to make approx 10 small brass tips to fit several Milne Pattern Champagne Taps that I have.

As they have a conical end and a square shaft I am not sure the best and easiest way to go about making these very small items.

It is possible that I may need to make quite a few more in the future.

Any thoughts will be much appreciated, I have an ML&, WM16 and collets

[Martin King 2Participant @martinking2]

[Martin King 2Participant @martinking2]

I meant, ML7, WM18 & collets!

Martin

[Ian ParkinParticipant @ianparkin39383]

I would start with some round bar and mill your square end using a indexer chop off and repeat to how ever many you need

then grasp the square end in a 4 jaw in the lathe and turn the taper

Ian

[JasonBModerator @jasonb]

1+

Though if you have a lot it may be easier to take round bar, turn the taper, over to the mill to do the 4 flats and then back to lathe and part off. This would save having to use the 4-jaw or find a suitable collet to hold the square.

Edited By JasonB on 22/07/2015 14:15:00

[Keith LongParticipant @keithlong89920]

I'd agree with Ian re the order of ops, but would consider making a square collet as per this link rather than using a 4 jaw – assuming that you can use collets on your lathe or can make a holder for the collet for this particular case. It would be a lot less fiddly especially since you envisage making more in the future.

Looking at the Arc catalogue it appears that your 3.5mm square falls between the sizes for 5C collets which look to be either metric 3 & 4mm or imperial 1/8 & 3/16th" in the square holding versions. Don't know if a 4mm could be persuaded to close down far enough – I suspect not seems like a step much too far.

[Martin King 2Participant @martinking2]

Thanks guys, The construction of HH's Square collet looks like it might be within my capability so will have a go at that having first tried Jason's method.

The Milne pattern taps almost never have the 2 points they were supplied with which were plated brass I think.

I guess that you had to rely on the butler to retrieve them from the empty bottle!

Somewhere (?) I do have one original for final measurement IF ican find it

Thanks again for the help.

[David Clark 13Participant @davidclark13]

I would use Jason's method. Turn all the cones, mill the squares and part off.

[AjohnwParticipant @ajohnw51620]

I would probably make them in 2 part using a self centring 4 jaw for the square plus small hole for the spigot I would leave on the pointed part – assuming that I could get 1/8" square brass and that being 0.013" under sized wouldn't matter. Or mill up the square bar 1st but in that case they may as well be solid.

John

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[Tony Pratt 1Participant @tonypratt1]

Posted by David Clark 1 on 22/07/2015 14:48:39:

I would use Jason's method. Turn all the cones, mill the squares and part off.

Turn the cones first then how do we hold the job to do the squares? It's possible but squares first is so much easier.

I don't think the OP has a CNC lathe with live tooling.

Tony

[David Clark 13Participant @davidclark13]

Use an overlong price of material, make them back to back and part off one from each end. Leaves a small stub of material but at this size material cost would be peanuts.

<——===——>

[JasonBModerator @jasonb]

I thought that by saying "then back to the lathe to part off" it would have been obvious it was still on the parent bar when being milled but for those not sure:

The thread would be the cone turned first, then over to the mill to do the square, this just happens to be a hex, then back to the lathe to part off leaving the square at the correct length. No need for small square collets, self centering 4-jaw or trying to set lots of parts in an independant 4-jaw or CNC, so much simpler than square first

Edited By JasonB on 22/07/2015 18:16:39

Edited By JasonB on 22/07/2015 18:26:20

[IanTParticipant @iant]

Jason's method is clearly the one to use Martin e.g. turn, mill & part off.

One suggestion to make milling the flats easier on your mill – would be to get an ER collet block (with a suitable collet) and use that to rotate the work squarely. They are not expensive and are very useful to have.

Regards,

IanT

[David Clark 13Participant @davidclark13]

Drill a hole in a square block and add a grub screw. Then rotate the block in the vice to mill flats

[Nigel McBurney 1Participant @nigelmcburney1]

This quite a small part,I would get a couple of lengths of bar, turn the cone on each end of each bar,then mill the flats in an index fixture,then part of.You then get four parts at a time rather than keep going between mill and lathe. I think a Myford 4 jaw only holds square bar 3/16 and up. Always avoid 4 jaw chucks on jobs like this if there could be a lot to make,too time consuming. If you try milling the flats first the square part is only 3.5mm across flats so turning after milling could cause the pointed end to deflect. If there was a lot to make it would pay trying out forming the taper with a wide tool rather than twidling the top slide handle a lot of times.

[Martin King 2Participant @martinking2]

I do have the square indexer that takes my ER25 collets so that bit is good to go. I like the idea of doing the operations 2 at a time at both ends of the stock.

[J HancockParticipant @jhancock95746]

Pre-fabrication ?

Square stock , drill location hole to take cone/ flux / tiny fragment of silver solder inserted in hole.

Round stock for taper with tit ( sorry) on end.

Heat , cool , polish.

[JAParticipant @ja]

My Myford four jaw chuck will hold 1/8" square bar.

The thought of parting off small square bar fills me with dread. My attempt at parting off 1/8" square steel bar ended in an awful mess and a complete rethink. I now intend to use a thin grinding disc in a Dremmal mounted on the cross slide.

JA

[Ian S CParticipant @iansc]

Martin, if (you do) you didn't have a mill, it would be just as east to put the square on by using a filing rest on the lathe, for some jobs this is quicker than transferring to the mill, and probably just as accurate as the original tips.

Wonder, are you going to nickel plate them to match the taps?

A Junior hacksaw would maybe be better than the Dremel.

Ian S C

Edited By Ian S C on 23/07/2015 11:16:30

Edited By Ian S C on 23/07/2015 11:18:46

[Another JohnSParticipant @anotherjohns]

Martin – If you were to ask me (and you'll not – read on) I'd stick them in my little CNC mill with the rotary axis, and just mill the little things.

If I were to do more of the little links I just did, I'd reduce the overhang greatly, but for the three I wanted to do, it worked a treat. Here is a bit more about the technique and finished parts: **LINK**

and a picture of them after a first (unsuccessful) run in brass:

[IanTParticipant @iant]

It's probably just me but this seems to be getting terribly complicated in parts.

I'd stick the bar in my 3-jaw, turn the pointy bit (with top slide set over), take the work out and use a collet block (or other simple indexing device) to rotate it 4x whilst milling, return the work to the lathe and part off (with a rear tool post), pull another length out and turn another point. Ad infinitum – and no wastage!

If I wanted to be absolutely certain that the point was concentric to the square (within the limits I can normally work to) – I'd also use a collet chuck in the lathe, either by buying a second ER collet or moving the one I had with the work (a bit more fiddly but quite doable)

The only issue then is how good you want the other (parted off) end to be. On small work like this, the finish from a sharp HSS parting tool should be quite good enough.

IanT

[Michael GilliganParticipant @michaelgilligan61133]

With a decent vertical slide and milling spindle, the whole job could be completed in the lathe, at one chucking.

MichaelG.

.

Edit: … or, as Ian SC  suggested, do the square by hand using a filing rest.

Edited By Michael Gilligan on 23/07/2015 22:58:20

[IanTParticipant @iant]

I have such a milling set up available Michael but (at least on my lathe) I'd have to keep moving between the milling spindle and the top slide & parting combo – I can't have both mounted at the same time there isn't room. It does give a very accurate result because everything becomes a "first" operation, as the work doesn't leave the chuck but it's not convenient for multiple units with my arrangement.

Doing them two at a time as suggested would probably help with the overall time spent but not the total material used, as the 'bit' in the middle – required to hold the two 'ends' –  is effectively wasted.

For myself, time is not an over-riding concern but I sometimes only have a limited amount of material. Sliding the work out of a 3J, moving it to the collet block wouldn't take me that long and everything is ready to go every time.

If a vice stop was fitted, the collet block could be set and rotated pretty quickly and some kind of stop on the lathe cross-slide would allow the part-off length to be set too, as the saddle could be locked.

It's often not the actual machining that takes the time in my experience but setting up the machine to do it in the first place.

IanT

 

Edited By IanT on 23/07/2015 23:30:24

[Michael GilliganParticipant @michaelgilligan61133]

Posted by IanT on 23/07/2015 23:29:53:

I have such a milling set up available Michael but (at least on my lathe) I'd have to keep moving between the milling spindle and the top slide & parting combo – I can't have both mounted at the same time there isn't room. It does give a very accurate result because everything becomes a "first" operation, as the work doesn't leave the chuck but it's not convenient for multiple units with my arrangement.

< etc. >

It's often not the actual machining that takes the time in my experience but setting up the machine to do it in the first place.

.

Ian … Yes, that's probably true for most such arrangements; but I thought it worth mentioning the advantage of the Vertical Slide. … As you so rightly said in your previous post: "It's probably just me but this seems to be getting terribly complicated in parts."

My comment was just 'a pebble in the pond' really.

To my mind; it would seem quite important to have the square and the cone concentric; and I would prefer to suffer other inconvenience if I could keep the work firmly chucked on one machine, throughout production of each piece.

MichaelG.

[Martin King 2Participant @martinking2]

Ian SC,

I'm not going to plate them, just not cost effective. The whole idea is that at least with a pair of tips the tap is in working order, otherwise of no use whatsoever and thus unsaleable. I know that no one uses them any more with the modern wired corks but collectors like them to have the tips.

Pouring with rain here so cannot refurb the CT-918 Warco I bought yesterday as it is outside so will snuggle up inside and have a go at these along with the 17 other smaller prepairs in the 'pending a rainy day' box!

new steel or brass roller for bookbinders roller tool x 2

2 new pivot pins and decorative nuts for USA Tailors shears x 3

several new brass ferrules for odd sized tools

mill the jaws square on some small table vices + make some alloy ones to replace wrecked items.

yet more small knurled screw caps for minute oilers, a job that initially took me ages but now can knock out a dozen in about an hour.

all good fun and worthwhile!

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