What Did You Do Today (2017)

[Joseph Noci 1Participant @josephnoci1]

This weekend I finally sorted my fogless coolant applicator. After many side roads with all sorts of pumps, peristaltic included, I finally resorted to the all compressed air driven system. Previously I could not get the coolant fluid flow rates finely controlled – the problem turns out to be the needle valve flow reducer. I made a few versions and variations, even used an old air-brush, and then used the handle grip/flow valve parts of a hand-held gas blowtorch – and what do you know! It worked beautifully! So, its all done, very nice coolant and air flow rate control, solenoid valve on/off, etc. I made it as a portable unit, so it can be traipsed between the two lathes or the mills. Works a treat!

Does look as though it should distill something though…

Gas Torch Flow valve

 

In its enclosure

 

Flow rates – Air on, about 1 drop of coolant every 4 to 5 seconds

Air on, 1 Drop every 2 sec

Air on , 1 drop every sec

2 Drops per sec

3 drops per sec

No Air, about 1/3 max stream flow rate

 

Next – fitting and swapping between machines

 

 

 

 

 

 

Edited By Joseph Noci 1 on 11/06/2017 21:31:44

[Joseph Noci 1Participant @josephnoci1]

My coolant applicator is swappable between all my machines, with not to much trouble…

Fits above the V10 splash guards

The nozzle feed assembly has a magnetic base and clips onto the cross slide extension.

Two pipes are air and coolant.

Nozzle assy on similar extension on the EMCO 14D cross slide

Unit fits on 14D splash guard, just left of the DRO

on the EMCO FB2 mill, the unit hooks onto the window burglar bars next to the mill…

With the nozzle applicator clamped onto the vertical head.

Glad that is done!

Joe

[BazyleParticipant @bazyle]

Chris, the tank cutter fits a carpenter's wheelbrace because…….that's all most people had back then!. That sharp thin blade won't do much in wood and not last long on the galvanised tank. More likely for leather washers after a thin chisel blade was used in it for cutting the tank. However those cutters will be great for plastic tanks.

Edited By Bazyle on 11/06/2017 22:07:20

[john carruthersParticipant @johncarruthers46255]

Looks like the tank cutter blades could be used together? one being longer than the other?

[Jon GibbsParticipant @jongibbs59756]

IME, one cutter will have a bevel on the inside and one on the outside of the circle.

You therefore use the one cutter which gives the best finish on the piece you're interested in i.e. bevel to the waste side creating a burred up part. As an alternative, and if you're feeling strong, you can use two to sandwich a double burred up waste area in between.

HTH

Jon

[SillyOldDufferModerator @sillyoldduffer]

Posted by Sam Longley 1 on 08/06/2017 17:29:02:

Posted by SillyOldDuffer on 08/06/2017 17:23:26:

Got up, thought about high policy in the shower and decided who should run the country.

Dave

Presumably whilst soaping the nether regions

Not quite: I was washing my smalls.

[Anonymous]

Posted by Iain Downs on 11/06/2017 18:46:56:

………….I'd guess someone with a bigger lathe would think it rough

Well now you mention it.

Out of idle curiosity I did a quick trial this afternoon. Material is EN3B, which can be tricky to get a good finish, diameter is 1¼". The HSS tool was one I dug out of the toolbox, hasn't been used for 50 odd years, and is probably 70+ years old. I gave it a quick lick on the hand grinder and added a small radius with a diamond hone. The results:

Right most was 0.05" DOC, 4 thou per rev and 540rpm. Moving left was 0.03" DOC, 2 thou per rev and 370rpm. Roughness measurements are:

Right: 5.43µm Ra

Left: 3.11µm Ra

To me the finish isn't great, especially at 4 thou per rev, although the swarf was curling and breaking beautifully, just like an insert should do, but at lower feedrates.

The finish you show is quite uneven; that implies that the cutting conditions are unstable. That could be for all sorts of reasons, eg, an unsteady cutting position, speeds and feeds not right, tool geometry not correct, or poor material consistency. The speeds you're quoting for HSS tooling seem quite high, they're not far from where I'd be with insert tooling.

Food for thought.

Andrew

[Iain DownsParticipant @iaindowns78295]

The cuts were done by hand with the big wheel so I have no idea what feed it was. It wasn't particularly smooth, though I do like to practice! DOC was a bit random, but likely similar to yours.

I'll see if I can have another go at this when I'm allowed out, with something closer to your specs. I'll need to put the gear train back on the lathe, but that won't take long. Also, the HSS toolbit isn't one I'm particularly happy with, so may grind another.

What is the lathe you did this on btw?

Oh- and I guess roughness is something you need a roughness meter for – not something I can do with my tooling? I do have a micron indicator, but the ball on the end would smooth out any variance like 6 microns!

Iain

[duncan webster 1Participant @duncanwebster1]

You used to be able to get comparator coupons, bits of steel about the size of a postage stamp with different finishes, all stuck into a little frame. Not something I'm desperate to have, I know when I've got a poor finish, most of the time. The answer is to not use any old bit of scarp, EN1A (230M07) machines lovely, especially the leaded stuff

[Mark RandParticipant @markrand96270]

Trouble is that also it rusts at any provocation and dents/scratches if you look at it crossly…

[Anonymous]

Posted by Iain Downs on 12/06/2017 18:13:28:

What is the lathe you did this on btw?

It was a Harrison M300, but I avoided mention of same to avoid the inevitable comments about it being an industrial lathe rather than a modellers lathe. Quite how the metal is supposed to know that, and behave differently, I don't know.

Correct that surface roughness measurement ideally needs a special instrument. Basically it's a record stylus and a measurement circuit. Mine was secondhand and measures Ra (average) as that was simple to do with the electronics of the day. Here's the kit, complete with comparator coupon (and the name of the original owner):

Measurement of Rz (peak to peak) is now popular, and easy to do with modern electronics, and possibly a more useful measure.

You can also get Rubert sets which are electroformed plates of varying roughness and with the characteristics of various machining techniques:

Mine was also secondhand, but they are still available new:

**LINK**

For the sort of finishes one would expect from turning the fingernail is surprisingly sensitive and perfectly capable of assessing roughness in conjunction with a Rubert set.

Of course it isn't essential to be able to measure surface roughness. I just like to be able to put numbers on parameters so that I can make sensible comparisons.

I'd agree with Duncan about not using scrap, and EN1A is definitely a joy compared to EN3B. Although my experience is that EN3B is less prone to rusting.

Andrew

Damn it, too slow; that's what comes of checking the post for comprehension and spelling. May be I should reserve that for ME/MEW articles.

Edited By Andrew Johnston on 12/06/2017 21:17:11

[Iain DownsParticipant @iaindowns78295]

I've put the leadscrew gearbox back in with 20/80/20/80 which I reckon gives me 5 thou per revolution (0.125mm).

5 thou cut (0.125 mm) and about 400 rpm. I ground a fresh tool.

What I find interesting is that the middle bit isn't bad (well, by my standards). There's a very fine groove and then suddenly it goes messy. All this is under power and me not touching it (apart from the press the half nut bit down securely).

after an earlier attempt I tightened up the lock nut on the spindle to add some preload. But its as tight as I want it to go for now as I don't want to risk damaging the thing (well its as tight as I can make it without grunting seriously).

It seems clear that there's something loose somewhere, but where?

I've not had the saddle off, but it seems firm. The cross slide has some backlash, and one of my jobs is to re-adjust the screws holding the screw and this time put some loctite on as they loosen up very easily.

Just keep pissing around with it until it works better, I guess.

Iain

[Clive HartlandParticipant @clivehartland94829]

That was fun, today i stripped my 7 month old Airedale bitch. She did not want non of it and wriggled and flopped down as I tried to cut off her puppy fur.

She eventually let me trim her tail and nether regions as she is very sensitive at that end. I had clipped her head previously and now had to trim the ear fur, next will be to trim the fur between her claws! Tomorrow I will use the stripping knife and even out all the straggly bits. I might add that last night she demolished her bed, I came down to find a pile of white foam bits all over the hall and kitchen floor. She managed to bite off the zip which I have yet to find!

Clive

[mechman48Participant @mechman48]

…She managed to bite off the zip which I have yet to find!…

​are you sure she hasn't swallowed it, ???

George.

[Clive HartlandParticipant @clivehartland94829]

More than likely George, she has swallowed lots of things as she eats her way around the garden. I have to assume if it does not stick in her throat it will not stick anywhere else, hopefully.

Clive

[Anonymous]

Posted by Iain Downs on 12/06/2017 21:22:22:

It seems clear that there's something loose somewhere, but where?

I don't think that the evidence supports that. My Harrison has at least 10 thou backlash on the cross slide, and I can move the cross slide back and forth by hand. But I can still achieve a good finish.

While rigidity helps, and has an effect on the metal removal rates, it has less effect on the finish. The key is achieving a stable cutting action. It doesn't matter if the lathe moves a bit under the cutting forces, as long as the movement is stable.

I've had cuts produce results exactly like what you are getting. I think the issue is within the cutting action rather than with the lathe overall. Some materials, especially EN3B, seem prone to tearing if the cutting parameters are wrong.

Your DOC, speed and feedrates look fine. So there are two other aspects to look at. One is the material; what is it and where did it come from? When I first started with my Harrison I had a similar problem with an inconsistent finish, and got quite down about it. Then, for work, I visited a local machine shop and as an aside asked them about material suppliers. I mentioned that I'd bought steel from a well known supplier in Cambridge. They said don't buy their steel it's inconsistent and gives a poor finish. I bought some more steel from a larger stockholder; and got a good finish straight away.

The second issue is the tool. It is difficult to tell from the picture but it doesn't look like it has much in the way of top rake? While the angles on tools are not critical they do need to be in the right ballpark. Top rake is the one thing I changed on the toolbit I picked out to get the finish I showed. From the box the top rake was only a few degrees and didn't give the finish I was looking for. So I reground it to be around 10° or so. That gave a better finish and much better chip control. The chips then curled round and forwards, and broke off in front of the tool in the direction of travel.

Ultimately, and not withstanding my waffle, it's all down to experiment. And the more experiments you do the better the heuristic database you form for speeds, feeds and DOCs that work.

Andrew

[Martin KyteParticipant @martinkyte99762]

Posted by Andrew Johnston on 13/06/2017 09:03:10:

Posted by Iain Downs on 12/06/2017 21:22:22:That gave a better finish and much better chip control. The chips then curled round and forwards, and broke off in front of the tool in the direction of travel.

Andrew

I'd go along with that. Certainly something I didn't appreciate for a long time. If the chip is being forced into the newly cut surface it is going to be detrimental to the finish. I'm currently on a big George Thomas drive in that I have spent several months going through his books and building quite a lot of his workshop equipment. In the course of this I have taken note of many more of his comments than I would have otherwise done. One aside regarding screwcutting was when using the set over technique at one stage he was getting a ragged surface on the flank opposite to that being cut. He tracked this down to the chip passing over the tool and rubbing on the flank of the tread and spoiling the finish. His answer was to change the geometry by setting to slightly less than 27.5 degrees (whitworth form) and allow the tool to take a small cut from the back flank which cleaned up the whole thread.

So as Andrew says take note of where the chips are going and relate that to the surface finish.

Happy turning.

regards Martin

[Martin KyteParticipant @martinkyte99762]

Sounds like one for you Clive

**LINK**

Martin

[Martin King 2Participant @martinking2]

Chris Gill: The 'tank cutter' is NOT for wood or metal, leather only. For making washers and sealing rings for equipment, pumps mainly but any old time gasket use. Obviously one cutter is wrong way round or put there to be out of the way for a single cut ring etc

We get LOADS of these and there are many different designs, one customer of ours in the USA has about 40 odd different ones. They are usually marked with makers name if you look carefully, WYNN TIMMINS is a common UK one.

Again there are many variants of the leather cased tapes, the most common makers being Rabone, (Hockley Abbey is one of their trade marks) and Chesterman. Lufkin, LS Starrett of USA also made them among others, Davis being the rarest USA type.

Also quite collectable but of little value in the common forms. The valuable ones are marked for cricket pitches and tennis courts and very rarely bowling greens. Smaller sizes often have steel tapes which if not rusty are more desirable.

Nice finds.

Regards,

Martin

[Neil WyattModerator @neilwyatt]

Posted by Clive Hartland on 12/06/2017 22:39:11:

That was fun, today i stripped my 7 month old Airedale bitch. She did not want non of it and wriggled and flopped down as I tried to cut off her puppy fur.

Luna the white lab is in moulting mode… which means much hoovering and ten minutes with the brush can quarter-fill a carrier bag. the hair seems to fluff up as it's removed. That's the price of having a dog with the same hairstyle as Douglas Hurd.

Neil

[NJHParticipant @njh]

Ah Neil

That is one benefit of Staffies – very short coat and no Hoovering after them…………however they do still shed some hair. Indoors I often walk about in bare feet and once had a painful pricking in the sole of one foot but nothing obvious to see. It proved eventually to be a short, almost invisible, Staffie hair which had worked its way into my foot! I tend to wear slippers indoors now!

Norman

[Clive HartlandParticipant @clivehartland94829]

Hi Martin, the bees swarm and at the moment are a bit late.

Hence the rhyme: A swarm of bees in May is worth a Load of hay. A swarm of bees in June is worth a Silver spoon: A swarm of bees in July is not worth a fly. I have two swarms that I took last month and they are not doing very well due to the weather, again.

The swarm flies out and the Queen never flown before will tire and seek a place to settle, anywhere! Meanwhile scouts go looking for a home. If they find one then off go the swarm to the place unless the bee keepers intercede and hive them. The car as a landing place is as good as a tree branch or a fence, it is just a resting place though a nuisance.

Clive

[Ady1Participant @ady1]

it is just a resting place though a nuisance

The Queen has some very powerful pheromones which bees can't resist and they hang around for days

We had a swarm land in a tree in the park last year and 4 to 5 days later there were still bees being attracted to that spot on the tree, long after she was gone

[MikeParticipant @mike89748]

Martin: One of my father's duties during the 1950s involved planning power lines to take electricity to rural villages. In school holidays I went around with him and helped him carry his kit. This comprised a theodolite, sighting rods, a surveyor's chain, and a leather-cased 50ft tape by Chesterman. Yes, we used what my mother always referred to as 'God's measurements' rather than this modern metric rubbish. After father's retirement I acquired the tape, and for years a pal and I used it for marking out circles for control-line model aircraft flying. I must still have it stashed away somewhere…

[Martin KyteParticipant @martinkyte99762]

Sounds like one of Niels Bands. 'Queen Bee and the Pheromones' although maybe it's a little too punk.

Martin

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