MEW180 CAD Article

[KWILParticipant @kwil]

Latest MEW has 5 pages devoted to a “concept” (nothing made) for a shaping device for a mini lathe. Is anyone really interested in this?

[KWILParticipant @kwil]

Shaping in a Lathe (Concept)

[Tony Pratt 1Participant @tonypratt1]

No, but somebody might be.

Tony

[NJHParticipant @njh]

Hi Kwil

 

Well I don’t see a use for this at present but the author cites the need for some square holes and is concerned at the strain placed on the lead screw etc by winding back & forth. IF I ever need to make lots of square holes maybe I will remember this and rig up something similar. So it’s value is in planting a seed which just might be useful in the future so I don’t mind.

In view of accusations of negativity in recent threads though, I will say this is a wonderful idea! ( At least it has some clear practical purpose!)

 

Regards

 

Norman

Edited By NJH on 10/08/2011 18:10:37

[David Clark 13Participant @davidclark13]

Hi There

If I have to cut a Keyway, I would certainly consider it.

I once had to cut some 8mm keyways in a hole 2 1/4 inches long.

This was done using a broach pressed through using a tailstock.

20 components and two days later I was well worn out.

 

This was a one off and not an ongoing feature.

 

regards David

 

[John Stevenson 1Participant @johnstevenson1]

Not much difference really in doing a drawing in CAD to see if it all fits or to get an elusive measurement.

 

If it only jogs a few peoples memory to do something similar then it won’t be in vain.

I have found with mags like MEW that what doesn’t interest me one month will a few months later.

 

I can see the practical purpose of the article even if not that interested in the subject.

 

PS> I did like the yellow levers and parts, how do you get that finish ?

 

John S.

[David Clark 13Participant @davidclark13]

Hi John

I don’t think Linton is on the net.

He used Truespace as he used in the series in Model Engineers Workshop.

Oh dear, have I started another controversy?

regards David

[Jim NolanParticipant @jimnolan76764]

David,

I was thinking that must be your plan?

Given the mount of heat every issue of MEW generates I think I am missing something and should take out a subscription!

Then I might not find these endless debates so boring. I am guessing if you don’t like the content you could always stop your subscription?

> >

Just like I could stop reading these posts but I do like a good barny.

[David Clark 13Participant @davidclark13]

Hi Jim

It was reasonably peaceful before they started this forum.

regards David

 

[Ian WelfordParticipant @ianwelford58739]

I have had it said that if you put 3 engineers in a room,and give them a problem that you will get at least 5 solutions, kostly contradictory and that each will argue ehir point.

 

Certainly looked that way in a club discussion evening we had.

 

I am not intending to make one of the aforementioned gadgets but the thought process is useful. he whole point in MEW , to me anyway, is to generate solutions. Sometimes the problem may not, at this moment exist ( for you ) but somewhere, sometime…..

 

Now off for a damn good weekends wood turning at Loughbrough!

 

Happy arguing! Sorry discussions folks!

 

Ian

 

 

[Chris TriceParticipant @christrice43267]

I’m afraid I agree with you Kwil. See the other MEW 180 thread. And I’ll state again that I have no issue with the design or that fact that it MIGHT be a good tool to do a job but it remains theoretical. It’s not something I feel particularly strongly about other than to explain why I hold the opinion I do but I did mention it because my first gut reaction was to feel short changed that the author hadn’t gone to the trouble to actually make it and check that it worked before encouraging others to do so.

[Steve GarnettParticipant @stevegarnett62550]

Posted by Chris Trice on 10/08/2011 22:39:45:

And I’ll state again that I have no issue with the design or that fact that it MIGHT be a good tool to do a job but it remains theoretical. It’s not something I feel particularly strongly about other than to explain why I hold the opinion I do but I did mention it because my first gut reaction was to feel short changed that the author hadn’t gone to the trouble to actually make it and check that it worked before encouraging others to do so.

 

That’s not entirely fair. At the bottom of the first page Linton has made it clear that he’s tried a ‘proof of concept’ test (see photo 2) and established that the basic idea works. He’s then described in some detail how an improved version of this might be constructed, carefully pointing out that the detail will almost certainly vary according to the lathe you want to fit it to.

 

Personally I can see no conceptual difference between this article and the one about fitting an inverter, which also isn’t step by step, or applying to any particular machine. They both have value in exactly the same way. So what exactly is the problem with that?

[Billy MillsParticipant @billymills]

I would agree that the “virtual project” is a good idea that could come in useful sometime. Often ideas may have no relevance today but be invaluable a few weeks or years later.

 

Perhaps a few more people might come forward with unusual ideas which have not yet been turned into hardware but could solve real workshop problems.

 

Billy M.

[Chris TriceParticipant @christrice43267]

Perhaps the presentation is the problem. Laying a virtual tool onto a real photograph accentuates the sense of fakery and being short changed. It’s not the validity of the design in question so much as the lack of apparent effort into making it a real thing. Why do stunts performed by clearly CGI characters in films lack any sense of danger as opposed to a real stuntman doing a stunt for real? The audience is very sophisticated and wants a sense of some effort having been put in after they’ve paid to be entertained. The arguments for and against virtual tools are all valid. However, I would submit that despite a percentage of readers not being able to understand where the problem lies, there’s clearly a sufficiently large number of people expressing discomfort with the trend that signals some aspect of the article is not popular.

[adyParticipant @ady]

A shaping device on a lathe?

Sounds pretty crazy to me….

[adyParticipant @ady]

[adyParticipant @ady]

Probbly the most sensible normal person approach would be a variation on a filing attachment which could be used for slotting small square holes.

 

lathe filer. popular mechanics 1957

 

 

 

[adyParticipant @ady]

The project is currently ongoing and has been for months, I’m a busy teddy bear most of the time, and only got to this stage 3 days ago so there are various geometric, loading point and  other issues to sort.

Prototype “Teething issues” lol.

 

The biggest unforseen issue is the backstroke.

The geometrics are like a proper shaper, going anticlockwise 2O’clock to 7O’clock are the power stroke while 6 o’clock to 3O’clock does the backstroke.

 

However.

The 3O’clock to 2O’clock backstroke point where the stroke changes direction is vicious and you can see the temporary green lathe belting rubber band which damps this event.

 

Any play in the keyway between the bullwheel and the spindle, (backgear engaged, 50 rpm) results in an unhealthy banging noise at this point.

It’s not an issue for lathe work, since the load is only applied at the fixed cutting tool point (at 9 O’clock) but a power tool which changes direction has a loading event (the faceplate balljoint) which constantly travels around the faceplate in an anticlockwise direction.

 

The solution I presume would be to dismantle my headstock and refit the bullwheel to the spindle with a proper tight fitting keyway.

Edited By ady on 11/08/2011 06:56:30

[adyParticipant @ady]

What I can say so far is….it’s nice to let the machine do all the hard work while I stand there with a big grin on my clock.

 

Workshop space is very tight for me, the reason behind the original idea, and I can’t go putting a proper 200kg powered shaper into an upstairs bedroom even if I did have the space.

 

No more milling cutter hassles ever again.(well almost none) I really really hate milling and just want to “get it over and done with”. Milling for me is no fun at all.

 

The price of a lump of simple HSS versus a milling cutter is…huge, and nothing annoys me more than a chipped cutter because something unforeseen happened even though I checked that everything was hunky dory.

 

Good squareness with a nice finish can now be achieved with relative ease.

 

[adyParticipant @ady]

I did a bit of research and guessing as to why shapers never really “caught on” like lathes did.

Circa 1935 a Drummond, a quality lathe was about $120 while the new Atlas “power shaper for hobbyists” was around $250, so they weren’t ever cheap, lots more moving parts compared to a lathe and around twice the cost.

 

Post WW2 production line techniques were focusing on speed and outputs, which were coupled with more advanced cheap and efficient cutter grinding, so this led to the mill becoming a standard issue unit in industry, it was more versatile for industrial purposes, while the slower more limited more sedate shaper was consigned to collecting dust as a workshop curiosity.

 

Shapers were still “cheap” as minor manual puff powered hobbyist units….but 5 minutes with one will have you searching for an easier solution unless you want to train as an olympic rowing champion.

 

So relatively few were made compared to lathes, the age of the simpler construction more versatile mill took over, plus hardly any books were written about shapers either.

 

However a shaper can still do most of the things a mill can if you’re not in a hurry, and nowadays they can be viewed as a relatively simple civilised alternative to working with a milling unit.

[Roderick JenkinsParticipant @roderickjenkins93242]

I admit to a certain disquiet when I first looked at the front cover. But then it occured to me that, as I understand it, many of the locomotive designs put before the readers of ME had only ever been seen on paper before they hit the newstands. So, if nothing else, the precedent is well established.

 

cheers,

 

Rod

[KWILParticipant @kwil]

Now that is all very good, certainly started off the discussion!!

There are of course plenty of small slotting tool designs aka shaper which fit on the toolpost and achieve the same result without racking the carriage up and down the bed. They use less effort to cut the metal because of that.

[John Stevenson 1Participant @johnstevenson1]

Posted by KWIL on 11/08/2011 09:28:47:

Now that is all very good, certainly started off the discussion!!

There are of course plenty of small slotting tool designs aka shaper which fit on the toolpost and achieve the same result without racking the carriage up and down the bed. They use less effort to cut the metal because of that.

 

 

However these suffer from lack of rigidity and short stroke.

Moving the carriage will have more mass to it, which helps,

Down side is the gearing for the handwheel and rack is now a step up gear and not a reduction which will cause drag.

 

John S.

[john jennings 1Participant @johnjennings1]

It is all very pretty but it is basically a rough sketch of a possible lathe attachment.

 

Considering the task that the gadget is designed for it looks a little light in construction.

 

Only actually making it will show exactly what it can do and it seems gross waste of MEW pages which could well have had an outline of actual construction and performance.

 

While I am being grumpy the same analysis applies to the cutter grinder in a previous issue.

This although based on a made object avoided discussion of what seemed to be the main item of interest – the use of a Diamond faced wheel and any costructional detail.

[mickParticipant @mick65121]

Hi Andy.

The ram will always return at twice the speed of the forward stroke. I can tell you from personnel experience that the Shaper was still a popular workshop machine well into the eighties, but mainly by those who knew how to use it to it’s full potetional. I had one in my own comercial workshop into the late nineties. There is no better machine to achieve a totaly flat surface and can easilly be set up to cut key ways, only wish I had room in my workshop (shed) to fit one like yours in, thats of course if I could locate one, enjoy it, I’ve always maitained that god didn’t rest on the 7th day, he invented the shaping machine!!!!

[Author]

Posts