Mega Adept

[JasonBModerator @jasonb]

Posted by Michael Gilligan on 16/12/2014 20:30:06:

That's looking really good, Neil

'though you might have rotated that big gear, for the photo

MichaelG.

Thats the good side

[Neil WyattModerator @neilwyatt]

Thanks… I think!

B****r! I have no idea when that happened! Its either fallen on something or had something fall on it, it's raised a bruise on the side of the tooth, so it isn't a machining error.

The good news is that, despite misgivings, putting as much static torque through it as I can with my hands, the backgear shaft shows not the slightest sign of twisting.

The ball was done with a the form tool that made the governor balls for Norden.

Neil

[Ian S CParticipant @iansc]

Good to hear about the lack of twist in the backgear shaft, I was a little worried about that.

Ian S C

[Neil WyattModerator @neilwyatt]

Pair of oil swivel top cups, now upgraded with lock nuts so they both face forwards!

Neil

Edited By Neil Wyatt on 19/12/2014 15:26:21

[Michael GilliganParticipant @michaelgilligan61133]

Neil,

You will have the GunSmiths tut-tutting: The flats on those lock nuts don't align.

… Cue flood of suggestions as how to fix that.

MichaelG.

[Neil WyattModerator @neilwyatt]

> … Cue flood of suggestions as how to fix that.

Shoot the gunsmiths?

Neil

[Steve WithnellParticipant @stevewithnell34426]

Looking pretty awesome Neil! By the way, the paint is Hammerite Blue – for those debating Adept Black / blue

Steve

[Neil WyattModerator @neilwyatt]

It's Humbrol Midnight Blue now!

😛

Neil

[Neil WyattModerator @neilwyatt]

Not as pretty as I would have liked, but I solved the bull wheel lock issue. A 3/8" long bush threaded 5/16"-32 goes in the back of the bull wheel, the end is rounded to fit the rounded recess in the pulley. Inside this is a sort of grub-screw, 3/16" – 40 tpi, with a 1/8" long 1/8" diameter tip. This engages a 1/8" hole in the pulley. using the bush to spot through for the pulley hole means they align nicely.

It's a bit of a squeeze to get the screwdriver tip in with the oil cup in the way!

Things will slow down now, as I have to design the screwcutting train.

Neil

[Neil WyattModerator @neilwyatt]

It's interesting looking for a suitable countershaft ratio. The back gear is fixed at 1:1 or 4.2:1, the pulleys offer 1:1.4 and 1.4:1 (i.e. two speeds in ratio 1:2). With an angled belt and a tensioning arrangement, I can also add 1:1 on the pulleys.

So the question is, what ratio to use for the countershaft? With a motor speed of 1450 rpm and a bit of help from Excel, countershaft ratios of 1.4:1 and 3.5:1 give an almost perfect spread of speeds:

C/Shaft	B/Gear	Pulleys	Speed
High	High	High	1450
High	High	Med	1036
High	High	Low	740
Low	High	High	580
Low	High	Med	414
High	Low	High	345
Low	High	Low	296
High	Low	Med	247
High	Low	Low	176
Low	Low	High	138
Low	Low	Med	99
Low	Low	Low	70

 

If I don't want the angled drive on the main pulleys, I can just have a third countershaft ratio between 1.4 and 3.5.

All this begs the question, why do so many machines have really poorly spaced speeds? Is it because the designers didn't have excel?

Neil

Edited By Neil Wyatt on 20/12/2014 12:44:07

Edited By Neil Wyatt on 20/12/2014 12:48:22

[Neil WyattModerator @neilwyatt]

I can't get that last column to stay where it is in the editor, but as it's below the ads, I'm leaving it…

neil

[Neil WyattModerator @neilwyatt]

Yes I can – all I had to do was format all columns as left-aligned.

Neil

[John Stevenson 1Participant @johnstevenson1]

there is actually a formulae for working out machine tool speeds.

Google " Mathematical Progression " or read here.

**LINK**

[Neil WyattModerator @neilwyatt]

And dug out the old three-step pulley I fabricated to keep my lathe going using a Hoover motor. It will give me ratios of 1.4, 2.5 and 2.6. Bonzer!

And it's comes with a countershaft with a long key that the three-step pulley will slide on and even has a 3/8" end for the two-step pulley. Bingo!

Neil

[Ian S CParticipant @iansc]

I have a genuine Adept counter shaft that I run the lathe from. The motor pulley that I use is 1", to the 6" pulley of the counter shaft, the double pulley on the shaft is the same size as the pulleys on the lathe. There would be no problem putting a double pulley on the motor, and another on the counter shaft, say a 5", to a suitably larger one on the motor.

Ian S C

[Steven GreenhoughParticipant @stevengreenhough56335]

Slightly off topic, but as the chap who asked about a super adept a while back, this is all good,inspirational stuff, and lovely to see (even if I’ve shelved my adept (for now anyway)).

[Michael GilliganParticipant @michaelgilligan61133]

Welcome back, Steven !!

MichaelG.

[Neil WyattModerator @neilwyatt]

Hi Steven

Afraid circumstances have kept me away from the workbench for a few weeks :-/

I have got a motor sorted though.

Neil

[Steven GreenhoughParticipant @stevengreenhough56335]

My adept motor was the last straw for me. I built a countershaft with some help fron IanT off here, got it all mounted to a temporary board and after about ten minutes running it went pop. Short version is I got a mini lathe instead… but this isn’t the place to expand on my experiences with that other than to say that one is slowly beavering away at it…

[IanTParticipant @iant]

Hi Steven,

I hope you are enjoying your new lathe and that you will also hang on to your Adept. Neil is certainly doing a master class on his Adept. Maybe one day you will be tempted to get yours out and dust it off again.

Regards,

IanT

[John Stevenson 1Participant @johnstevenson1]

Posted by Steven Greenhough on 26/01/2015 19:20:48:
(even if I've shelved my adept ).

.

Good decision……………….

[Steven GreenhoughParticipant @stevengreenhough56335]

Well that’s an “I told you so” some months in the making…

[Ian S CParticipant @iansc]

No problem with the original motor, if it started to slow down, you just went away and had lunch, it was a foot motor, very basic.

Ian S C

[Neil WyattModerator @neilwyatt]

You can't really blame the lathe for the motor going pop!

Neil

[Steven GreenhoughParticipant @stevengreenhough56335]

Well no, of course I can’t… it was more that I took it as a sign.

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