Member postings for Jack Foreman 1

I'm not sure if this is the correct Topic Section for this. If not, can a Mod move it appropriately please?

Started from a small aluminium billet. 4 spigots, each in line on their respective centre-lines.
1/4" ~ 3/8" ~ 7/16" ~ 1/2"
Accurate to 0.0005"

Probably not the best turning in the world, and certainly not the best photography, but I'm pleased with the result.
Approx 3 hours. So I'm unlikely to be offered a job in industry

Edited By Jack Foreman 1 on 02/10/2014 15:47:24

Edited By Jack Foreman 1 on 02/10/2014 15:47:53

Edited By Jack Foreman 1 on 02/10/2014 15:48:32

Did you make that with a UNF thread Nobby ?

Thank you, each. I stand admonished.
I see that I need to gain a new perception of 'accuracy'. I will always use a micrometer where it is possible, but confess to using a vernier to determine the diameter of a hole. I possess only external micrometers. o-1" & 0-2"

I will return to Mr Hall's exposition on hole and dimension gauges, and re-read with a fresh insight.

I was recently at Chronos in Dunstable, and spotted two books.
One by Harold Hall - A Complete Lathe Course.
One by Stan Ward - Seven Useful Things To Make

Harold Hall has a Chapter specifically entitled Gauges.
And he talks of hole gauges and dimension gauges.
In common with many technical authors, he assumes that his reader will know what he is talking about when he refers to an item by its technical term.

I assume that a hole gauge is used to determine the exact diameter of a given hole. But why not use a vernier? Likewise, I assume that dimension gauges are used to determine the length of something - by using multiple of component gauges. But again, why not use a vernier?

Are my assumptions about the gauges correct? Or have I missed the point completely?

Finally, how useful, in everyday practice, is a scribing block?
Is it worth me making one?
I understand that making one would be a useful exercise from an engineering point of view - but I have a couple of projects in hand [for my wood-turning lathe and bench grinder] that would provide a similar range of activities and experiences.

I'm going to the Midland Eng Exhib at Leaminton on either the 16/17 Oct, with an experienced engineer - so hope to do some shopping and pick up some useful tips too, whilst I'm there.

Edited By Jack Foreman 1 on 30/09/2014 19:26:35

Edited By Jack Foreman 1 on 30/09/2014 19:27:29

How do I visually tell the difference between silver steel and any other bright round bar? Or do I need to determine by passing a file across it?

Thanks
Jack

I made two spacers and clamp plates to attach a large 'V' belt pulley to my faceplate. The first job I've done which required working to reasonably tight tolerances. Also the first time that I've used the faceplate. Centered the pulley on the plate OK - bored a 19mm hole - bored it out to exactly 1" ( I got it to within one thou.) Made a sleeve to fit the pulley shaft and turned the sleeve to fit the one inch pulley hole. It all fitted precisely. So my Mk1 Myford now has 6 speeds, as I was told it had when I bought it [only to find that the back gears didn't, and couldn't possibly, work] Comparing it with the Bantam [I don't have a rev counter] I now have a Myford lathe, in good condition, ready for sale with a speed range of approx. 300 - 1600 RPM.
I also took the backplate off the Myford small three jaw chuck and set it up in the Bantam chuck, clocking it for true [another 1st for me], accurately re-machined the register so that the chuck runs true now. This was my first time of removing the spindle jaws and replacing with the external jaws on the Bantam three jaw chuck. Not the ordeal that I expected it to be.
So, a productive day. And a learning day too.
Elementary to you guys, I'm sure. But another significant milestone day for me.

Edited By Jack Foreman 1 on 09/09/2014 22:03:32

A useful source of information Pete. I did read this carefully before posing the question.
What these articles do not provide, valuable though they are, is experiential wisdom. Hence the question.
Also read the Victoria offering at the the same source.

Thanks Chris.

The present radial arm drill just does very fundamental drilling operations. Mostly through timber. Occasionally through ferrous and non-ferrous materials. Very seldom, through plastics, nylon etc

Chris, thank you for your response. Very positive. Much appreciated.

I wasn't planning on buying a mill for maybe another year. My thought was to become totally familiar with the Bantam first. But .......
Whilst I still have much to learn in terms of turning expertise, I find the Bantam to be so user friendly and versatile that I am happily engaging upon work which I never imagined that I would be even contemplating at this stage. So ...... When the Elliott appeared on the horizon, I was immediately drawn toward it.

This particular machine is single phase -240V - but apparently does allow all four motors to operate, Whether they will all do so at the same time is something I do not know. And will be one of the first questions when I view it.
The seller has also acquired a Bridgeport, hence the reason for the sale of the Elliott.
I confess that I know absolutely nothing (even less than I knew about metal lathes) about milling machines
So I will be taking my friend from across the road with me, to view it. Whilst not a qualified engineer, he has been involved in the engineering fraternity for something approaching 30 years, so knows considerably more than I do.

As to "overarm, all arbors and the steady is with it, and if you are lucky you may have a full set of feed change gears", I have no idea what else is available. There was certainly no photographs of anything other than the turret mill.
Are parts for the Omnimill still available? Or can they be made?

My thought was to dispose of (sell) my floor standing radial arm drill, and replace it with the mill. I do use the radial dril quite a lot in the course of my woodturning, but hope that I will be able to adapt the mill to do what the drill presently does. Is that a feasible scenario?

Welcome Brian, from another new member.
I'm sure that you will benefit from joining. I have benefited greatly from subscribing to ME & MEW, and the mass of information which is contained within those mags. Online access to more mag articles than you can throw a stick at, is priceless. Like you, I suspect that I may never become a model engineer, but I love making/repairing things.

Does anyone have any experience of an Elliott Omni mill?
Good, bad, or conjectural?

This one is a turret and horizontal machine. Four motors. Power feed to the bed. Looks in good condition from what I can see. Price £800. I have no idea of the YoM, but it appears well looked after

Comments would be appreciated.

I had no intention of purchasing a mill just yet, but >>>>>

I love the Bantam - I really feel that it belongs to me now.
I've made lots of pieces - some for the Bantam; some for the wood lathe; some items for around the workshop.
My friend across the road, keeps coming over, wanting to use it.

TIA
Jack

The Elliot is very impressive Graham. Well done.

It was a generalised question Les. In the respect of tapers being on of the present subjects of my learning and development. There was certainly nothing specific about it. And the replies and conversations have been very helpful.

From a geometric and mathematical perspective, Ian's assertion is true. And becomes increasingly so proportional to the increase of the pitch if the taper. In the same way that a cutter not positioned exactly central on a 4" billet will not be adversely noticeable; whilst the same discrepancy applied to an 1/8" bar will be patently obvious, due to the failure to meet the perpendicular of the tangents at the intersection of the small circumference.
However, I suspect that Rod and John's observations are equally valid The discrepancy will be much less than my present ability to perceive it.

I have spent an enjoyable, educational and interesting morning working through a lot of the advice which so many of you kindly provided. And whilst certainly not in the 'expert' class yet, I do feel that I have a 'competent' grasp of the matter now; including familiarizing myself with the set up for internal tapers. Thus, another part of the learning curve taken on board and available for practical development.

Edited By Jack Foreman 1 on 11/08/2014 16:13:26

Thank you each, and all. For your wisdom, and patience
I have learned a great deal from your offerings.

I have, this evening, subscribed to the ME Workshop mag, having subscribed to the ME mag when I first registered. Hopefully, this will curtail my necessity to ask questions - though almost certainly, not entirely.
Both publications will provide some suitable work exercises for me to attempt - to gain practical experience/

I'll design a protractor which will fit onto my cross slide traverse, upon which I will be able to set my x & y dimensions, then rotate the compound slide until it touches the protractor face along its length.
Theoretically, that will eradicate the guesswork.

Is this concept what you refer to as a sine bar Michael?

Ah. So it is a trial and error means of attaining accuracy. Thank you Frank.
Stay with the given x & y dimensions [or factors of them] and forget the minutes and seconds. That makes sense. Much appreciated.

A very simple question with, I trust, a very simple answer. However ......

If I wish to turn a taper of a given length (x) and a given magnitude (y) the trigonometry is very simple. But how do I translate the minutes and seconds divisions using the angles on the compound slide, which has only degree divisions?

Am I missing the obvious? Or am I going about the exercise in the wrong way?

Jack

The short bed Bantam is 71.125" ~ 1806mm long x 25.5" ~ 648mm [incl cross slide] wide
Colchester recommend a min. working area of 7'-6" ~ 2286mm wide x 8'-0" ~ 2436mm long.

I suppose, upon reflection, mine takes up most of that min. allocation. The suds sump and access to the change wheel storage add considerably to the footprint, or even the suds tray, depth of the machine.

HTH

Michael, I'm amazed at how compact the Bantam is - for such an industrial format of machine. Not much longer than a Myford. Bulkier, of course. And with the suds chamber hanging on the back of the tray, quite deep.
I really can't wait to get something which requires a multiple production, so that I can use the collets in earnest. What does impress me, with regard to the 2HP inverter fitted, is that there is no evidence of a reduction in torque, particularly at low speed revs. And 1600 revs is, I suspect, all that I will ever require. I'm finding that I tend to use recognizably lower revs for a given diameter of work, than my neighbour across the road, who owns the Boxford CUD.