Glanze Parting Blade – question

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Glanze Parting Blade – question

This topic has 25 replies, 10 voices, and was last updated 2 December 2009 at 18:16 by mgj.

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27 November 2009 at 20:21 #16510
LADmachining
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@ladmachining
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27 November 2009 at 20:21 #45658
LADmachining
Participant
@ladmachining
Hi.

Does anybody use the following parting blade?

http://www.chronos.ltd.uk/acatalog/info_CGG121.html

I had a ‘dig-in’ earlier and broke the insert, as well as slightly springing the jaws of the support blade open. Of course, the other end of the blade can be used, and I just need to get some more inserts. Question is, is there a tool for removing/fitting the insert? If not, how is it done, as the remains are still quite a good fit in the blade.

Regards,

Anthony
27 November 2009 at 21:07 #45661
Billy Mills
Participant
@billymills
Hi Anthony,

The insert has shallow vees on two tapered faces, it pushes onto the holder which has matching vees. So any unexpected forces and it becomes an Unexpected Flying Object.

Of course this should not happen, the reaction from parting should be pushing the insert into the taper. So far I’ve been lucky with mine, but a good reason for having eye protection. You do need to make sure that the tool is at the centre height and cannot deflect downwards to then dig in.

It would be good to have a few words of advice with this tool as it is not as forgiving as the traditional parting tool.

regards,

Alan.
27 November 2009 at 21:14 #45662
Tony Pratt 1
Participant
@tonypratt1
Hi Anthony, I haven’t used this particular brand of parting blade system but I would imagine it is the same as the Sandvik / Kennametal / Iscar parting systems I have used in an industrial environment. There is indeed a special tool for removing the inserts, it is basically a piece of bent 5mm dia? rod [proportions as per an allen key] The small end is flattened to about 1/3 its dia.

The tool is placed behind the insert to be removed and a quick twist will free it. When I put a new insert in place I like to give it a light tap with a piece of Nylon to seat it. All the parting tools I have used came with this tool as standard so give Chronos a ring and I am sure they will send you one.

Tony
27 November 2009 at 21:28 #45663
mgj
Participant
@mgj
I have broken a tip, but the cause was an upward deflection of the work. Stupidly I was parting a relatively thin section of stainless without tailstock support, and it went up, which chipped the tip and also did one end of the blade. It does still work, but I have reversed the blade anyway. If the tip is jammed, tap it out with an old screwdriver. It is a push fit in.

The one that does use a tool, and does grip the tip very firmly is the Kit Q cut from Greenwoods, which uses standard Sandvik tips. I am not going to replace the Glanze tip – I’m going to buy another Qcut when the time comes. The Sandvik geometrey is freeer and faster cutting, and folds up the swarf a lot better, and there is a much greater range of different tips for the same holder for specialist tasks if needed.
27 November 2009 at 22:32 #45666
LADmachining
Participant
@ladmachining
Thanks you for your replies.

I will contact Chronos tomorrow and order some spare tips, and enquire about a removal tool.

The dig-in was my fault – I was parting through a piece of 1.5″ aluminium bar, got most of the way through, but didn’t make a wider slot to begin with to allow the chips to clear. I think I will also have to rig-up some sort of coolant system, as I was just about to douse the work in WD40 as the scraping noise started. Before I could back the tool out – CRUNCH!

Anthony
27 November 2009 at 23:11 #45667
mgj
Participant
@mgj
With respect, the Sandvik tool is, nowadays at least, nothing like that. Its quite sophisticated, with a yellow plastic handle, a shouldered boss for the fulcrum, and another sprout to go behind the tip. You put the shouldered boss into a hole in the blade, the ejector sprout goes behind the tip, pull on the handle and out it comes. Fit it the ejector peg on the other side of the tip and it pushes the tip in firmly.

I didn’t get a removal tool with my Glanze tool, and other (Italian) blades which take the same tip as the Glanze don’t give you one either.

Anthony – you don’t need to cut a wider slot. The tool blade is narrower than the tip, so the only points of contact are the very front edges of the tip, and the cutting edge. Coolant, yes of course – most unwise IMO to cut ali with anything without coolant because it picks up like fury and particularly on tungsten with which it has an afinity.

Other thing to check if you are going in deep with a narrow blade and not much clearance is that the blade is truly square to the job. They are not designed to cut wide slots of course – while they are very rigid top to bottom, they are quite flexy side to side, and no one on production is going to cut wide slots unless they HAVE to – time, energy and wastage.

I don’t mean to be unkind, but I’m quite happy to part off 3 and 4″ bar with just a single slot, straight in. But to try to do it without coolant, with all that expansion towards the tool etc – that was unwise. And when I say coolant, I don’t mean a little dob of WD40 (which is NOT an extreme pressure cutting liquid) from an aerosol can – I mean coolant under pressure from a proper pump, though a 2 mm needle directly into the slot – it doesn’t flood everywhere and make a mess, but there is coolant and plenty of it pouring through that slot. ie I mean keeping it cool.

Coolant systems don’t need to be expensive – gravity feed works well from a 5l can. For a long time I used an old mini fuel pump for a recirculating system. But they do have to cool the thing.

Certainly you can get away with a few drops here and there turning externally (but not if you are using heavy cuts and don’t want the job to heat up which leads to inaccurate micrometer readings) but you cannot do the same parting off in deep slots.

As you can imagine, I don’t have much time for suds and WD40 and all the other famed wonder recipes which are so much better than the purpose designed stuff. (soluble or neat) Or so people say.
28 November 2009 at 10:59 #45678
Niloch
Participant
@niloch
Any advice about parting brass please? I have a Kit Q Cut and a Super 7, no power X feed. Speed, feed, coolant etc? Many thanks.

Edited By Niloch on 28/11/2009 11:00:13
28 November 2009 at 11:04 #45679
Paul Boscott
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@paulboscott25817
Hello Anthony

I popped the insert out just to see how it fitted in (as you do) with an allen key. I chose one that was a good fit in the hole behind the insert and one of its flats snug to the rear of the insert turned it and had the insert in my hand.

Paul
28 November 2009 at 15:08 #45694
Circlip
Participant
@circlip
Niloch, NO top rake, No coolant, dash straight in steady feed and wear safety specs against the “Golden Rain”
28 November 2009 at 15:18 #45695
KWIL
Participant
@kwil
I agree, do not be afraid of it, keep the feed on and do allow it to stop cutting due to insufficient feed. If you do you will merely polish it. I find that by starting with the blade tip wet with coolant [Neat Oil] the first cut material does not stick but keeps rolling off. If anything sticks in the slot you are cutting, back the tool out to clear and then push on in again. You should not have golden rain but a fairly continuous strip swarf. I rarely use the PCF because I like control of the parting.

Edited By KWIL on 28/11/2009 15:19:00
28 November 2009 at 16:43 #45697
Tony Pratt 1
Participant
@tonypratt1
Hi Anthony, I have just had a rummage in my “Tooling” store and have actually got a Glanze parting blade and tip which I can’t even remember buying and certainly haven’t got round to using, unfortuanately no removal tool to be seen !!

As Paul suggested I had a go at tip removal with an allen key. A 1/8″ A/F fits a treat and a slight turn free’s the insert, worth a go if you are stuck.

I believe Meyrick is right in what he said about Sandvik tip extractors, I do recollect some plastic handled thingy now he has jogged my memory.

Tony
28 November 2009 at 16:47 #45698
mgj
Participant
@mgj
Niloch you have a decent lathe and a decent tool. Go munch it. If it chatters slow down or add tailstock support.

I do keep coolant on brass- not because it needs it, but because it stops the golden rain dead. Less cleaning up afterwards. I hate brass.

A KitQ cut is going to walk though it.
28 November 2009 at 17:15 #45699
chris stephens
Participant
@chrisstephens63393
Hi Guys,

Just to add to the good advice given above, don’t have too much of the blade poking out. It may be a bit of a fag, but only have just enough, plus a bit more for bad luck, of the parting tool unsupported. Even if you have your tool 100% square to the work, the longer the bit exposed is the greater temptation of it to flex. You can be a bit more “Cavalier” with your parting on small stuff with small extension, but do bear in mind deep parting with long extension is more likely to cause problems at the start of the cut.

I use a parting tool with top rake on brass, but only up to about 9-10 mm depth of cut

( 1/16″ wide, blade type), any thing bigger I use more normal tools. I am quite mean so I try to use a thin parting tool where possible. Coolant is good, you only have to pick up the bit you parted off to realize this!

chriStephens
28 November 2009 at 18:07 #45702
Niloch
Participant
@niloch
Circlip, KWIL, Meyrick et al:

Thank you.
28 November 2009 at 19:36 #45703
Niloch
Participant
@niloch
KWIL,

Respectfully, as always; should that do (14th word) be a don’t?
29 November 2009 at 08:58 #45709
Ian S C
Participant
@iansc
This should be in the safty thread-don’t part off with a between centers,or even with the driven end in a chuck,when you get near the end of the cut you should get a good jamb up.IAN S C
29 November 2009 at 09:52 #45712
mgj
Participant
@mgj
Ian I agree about parting between centres – the thing will chatter insanely anyway.

But in the chuck at one end with a tailstock running centre. Well thats what I was taught to do, in the apprentice shops at DQA. Do it as my preferred method of parting off to relieve pressure on the headstock bearings and have been doing so for something like 25 years.

Never had a jam up of any sort yet. You get to the end, and the bit you have cut off stops turning. Why will it jam – its 2-3mm short of contact, and there is a 2-3mm wide bar (the parting tool) stationary between the stub and whatever is turning, and it is held in place against the parting blade by the centre, so it doesn’t drop out. It just… ..stops..

Very long overhangs I’ll use the fixed steady on the tailstock end, with a running centre, and cut up against the travelling steady.

Edited By meyrick griffith-jones on 29/11/2009 09:55:05
29 November 2009 at 12:01 #45717
KWIL
Participant
@kwil
Niloch, got it in one!!

All, yes between running centre and chuck, never jams or chatters, keep the speed correct for the job. Works for brass, stainless, ord steel and alu, just a touch of starting coolant and you are away. Another thought, these inserts last a long time but not for ever, look at them occasionaly!
29 November 2009 at 14:36 #45721
chris stephens
Participant
@chrisstephens63393
Hi All,

I have often heard that one should not use a centre at the tailstock end when parting. I can see why one wouldn’t want to at the conclusion of the cut, the forward pressure of the cut bending the material and closing the gap causing a “pinch” situation, but it can help in preventing chatter at the start of a cut. Chatter should be avoided at all costs when parting Stainless in particular, the rubbing part of the chatter causes surface hardening which even a good carbide tip may have difficulty geting through without making the situation worse.

I would suggest using the tailstock centre, if needed, but relieve the tension as heat builds up or when you get to the conclusion. All other conditions for good parting being met first, naturally.

chriStephens
30 November 2009 at 00:01 #45744
Ian S C
Participant
@iansc
OK meyrick I,ll concede,I,v never been in the situation where I’v needed a center against the end,but just going by what I’d been taught,I was also told not to use power feed,but that might have been on the lathes at school.I can get 35mm through the mandrel so I can get most of the stuff I part of close to the chuck.I would love to have a carbide tool,but have no trouble with HSS.IAN S C
1 December 2009 at 21:23 #45803
mgj
Participant
@mgj
Ian perhaps you’ve never lived with a Myford!! they are a great little lathe, but when its your only one, sometimes you have to stretch it a bit, or you’ll be hack sawing all night.

Like you, now I can get 40mm though the headstock, so I can invariably part off very close to chuck jaws – which as you suggested, is best practise.

Carbide is pretty good. You can work very happily IMO without a carbide turning tool, unless you start getting into some very special materials. But for parting, …..carbide is really really really nice. Not essential of course. But really really nice, like worth paying a lot of money for a holder and tips nice. !
1 December 2009 at 22:51 #45809
chris stephens
Participant
@chrisstephens63393
Hi Meyrick,

I wonder how much of the benefit of carbide parting tips is due to the material and how much due to the clever geometry of the tip?

chriStephens
1 December 2009 at 23:14 #45810
mgj
Participant
@mgj
Probably the geometry, and I suspect 4 elements are key

1 The way they fold up the swarf which keeps lubricant flowing to

2. A very small contact area.

3.They operate with very very little rake.

3. They are not that sharp.

So they don’t jam with the swarf, and resist being drawn in – ie you HAVE to keep a positive load on to keep them cutting.
2 December 2009 at 12:13 #45821
Ian S C
Participant
@iansc
The new Myfords with the bigger mandrel will be a great help to those who can afford them,still a light lathe,but every little helps!I’v parted old half shafts with HSS after wrecking a bandsaw blade,slow back gear(60rpm)lots of suds,keep it cutting don’t let it rub.I suppose carbibe would sail through.IAN S C
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