New lathe arrived today : The ongoing saga

[JasonBModerator @jasonb]

It was something to do with teh size of your images, sorted now

[HopperParticipant @hopper]

Posted by JasonB on 28/10/2015 16:18:24:

It was something to do with teh size of your images, sorted now

Thanks Jason. I usually set them at 320 wide, is that correct? Maybe just a typo in the setting box etc.

[JasonBModerator @jasonb]

Not quite sure what was actually doing as it looked OK it but I reposted them at the 640 width which looks like how you have photobucket setup to resize anything to that size, same as me.

[Howard LewisParticipant @howardlewis46836]

Thanks to Hopper, Brian is going to know more about his lathe, and possibly have a better tuned one, that I ever have.

Good on yer, lads! You inspire, and educate, me, (as do many posters on the Forum)

Howard

[VicParticipant @vic]

I was under the impression that "Optimum" Lathes were supposed to be a premium (Chinese) product?

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Vic on 29/10/2015 20:07:18:

I was under the impression that "Optimum" Lathes were supposed to be a premium (Chinese) product?

.

To judge by the Euro 'recommended retail price' one might reasonably expect them to be.

**LINK**

MichaelG.

Edited By Michael Gilligan on 29/10/2015 20:40:03

[JasonBModerator @jasonb]

You only need to look at some of the personal websites of German model engineers to see some very high quality work that they do on their Optimum and Quantum brand machines. Such as this one

Price is about the same as Warco want for a similar 280×700 be it pink or green

 

Edited By JasonB on 29/10/2015 20:51:59

[Brian JohnParticipant @brianjohn93961]

I bought a proper Abbott and Ashby 6 inch bench grinder with 25mm wheels today. It is now fitted with a fine green grit wheel (on the right) for touching up brazed carbide tools. The original bench grinder I purchased only had 13mm wheels and green wheels are not available in this size so I took it back.

Edited By Brian John on 30/10/2015 06:27:30

Edited By Brian John on 30/10/2015 06:28:53

[MadMikeParticipant @madmike]

Is it me???

On the 25th August, barely 8 weeks ago the OP reported "……my new lathe arrived….."

So after 8 weeks, or so, 33 pages of messages on here, visitations from that nice "Mr Hopper" and all of the advice given freely and generously the problems with this so called "new lathe" are still not sorted.

Frankly if I had bought a piece of equipment like this and it did not do the job it was designed for then it would have gone straight back to whoever sold it to me. Like it or not it appears to be a crock of s**t, and is clearly not fit for purpose. Please do not try and convince me that, it is only a model making lathe and so we should not expect too much from it, or that it is Chinese and that's what you get for your money, or that because you are in the Australian outback nothing can be done about it. That is all rubbish.

Get your money back and start again. I am stunned that in this day and age nobody has said this earlier.

Sorry to piss on everybody's (possibly everybody's) parade but this product is not fit for purpose.

[Brian JohnParticipant @brianjohn93961]

Okay, send it back and buy what ?

I wanted a small lathe because it is set up in the corner of my living room. I live in a one bedroom apartment ; I do not own a house with a workshop where I can install a large lathe. If I had my time over I would probably buy the US made Sherline as they seem to be problem free straight out of the box but they do cost twice as much.

I was in at Coles Tools today where I bought the bench grinder. I did not know until recently that they sold lathes They have a nice Hafco L160 lathe in the back room : it looks like a very serious bit of kit.

Where is the carriage adjustment on large machine like this ? I assume that it is NOT under the carriage

**LINK**

[HopperParticipant @hopper]

Brian, they all have that adjustment in one form or another under the bed. Ordinarily, they almost never need adjusting once properly set.

So, I spent a little time at the "metrology bench" yesterday measuring and remeasuring the bed and carriage using various methods to verify each other so we can be sure of our results using somewhat makeshift equipment.

Long story short is that the bed when i first checked it had a slight bow upwards in the middle area of about .002" on both front and rear ways. But then from the point about 5" from the tailstock end, the upper bed ways both drop .005". That is one thou per inch, or 12 thou per foot. (0.3mm per 300mm). Normal spec for a lathe bed is in the realm of .0005 per foot. Note the extra zero. So it was out of tolerance by a factor of 10. Also, the rear way was reading about 4 thou higher than the front at the headstock end when checked for level.

Note the past tense. All is not lost. I spent a little while cleaning up the ways with burr file — a well worn single cut file – laid flat along the ways. Then finished with a small slip stone. Result, the numbers came a lot better except for that 5 thou droop on the tailstock end. Brian wont be using this end of the bed for his small model work so I think we can work around it.

The original finish on the ways was as someone noted earlier, a bit like a linished finish, full of ridges and valley and all edges good and well burred. Smoothing it all down without removing significant metal or changing base dimensions has done the machine the world of good.

A few pics of the mucking about in progress:

Lathe set up level on shims then checked at both ends of the ways. Using my old Rabone precision level, a loupe and a piece of masking tape for marking the precise bubble position. Four thou feeler gauge was required at the end to get a level reading. But of course, later testing revealed most of the problem was that last 5 inches a the end of the bed.

Stood the lathe on a sheet of thick plate glass on a 40mm MDF counter top and measured with dial gauge on a scribing block the distance from the "surface table" to the top bed ways. By checking the the lathe in various locations on the plate glass, was able to determine it was flat enough for our purposes. You can see in the below pics that the front way drops off a couple of thou at the headstock end. I found this can easily be remedied by the way the bed is clamped down. Unfotunately the lathe uses one central mounting bolt each end, so the final set up on Brian's bench will have to be down with shims under the edges of the pad to pull the twist out and get it turning truly parallel. More of that later.

You can see above the five thou drop off on the right hand end of the ways. I just hope the other end is not the same, where the headstock is mounted. That could be a bit of a PITA.

I double checked these readings with the DTI on a small magnetic base attached to the carriage and the needle bearing on the glass. The actual travel of the carriage was a little bit smoother than the raw way readings, but still that huge drop off at the RH end. Lost the pics of that in the system somewhere though.

So the next step will be a little bit of stoning and scraping on the carriage ways to get them smoother and better matched to the bed ways. Then once we get the carriage riding as well as we can, will finish off getting the lower bed way surfaces dead parallel to the top ones. About two thou to go there.

Once that is done, we will be able to refit that lower gib plate and get the carriage sliding from end to end smoothly and without binding or slack. The right hand "end" will be that point 5" in where the drop off starts. I visited my mate today with the new 7×14 mini lathe and those lower ways are machined quite smooth and the gib plates set up so there is minimal drag and zero up and down or rotational movement at all. On bigger lathes, the spec for those lower ways is to be within .00075" over a 48" length — so zero-zero in real world terms.

Once all that is done, we can then fit up the cross slide and top slide and then maybe run some test bars to see how it does.

[HopperParticipant @hopper]

Posted by Vic on 29/10/2015 20:07:18:

I was under the impression that "Optimum" Lathes were supposed to be a premium (Chinese) product?

Premium German product according top the labels on the front of the machine. I think not.

[HopperParticipant @hopper]

Posted by JasonB on 29/10/2015 20:43:30:

You only need to look at some of the personal websites of German model engineers to see some very high quality work that they do on their Optimum and Quantum brand machines. Such as this one

Price is about the same as Warco want for a similar 280×700 be it pink or green

Edited By JasonB on 29/10/2015 20:51:59

Some stunningly beautiful models there for sure. I wonder if they are his own design, or is there a whole world of plans/kits on that side of the language barrier we don't see from this side?

Looks like his lathe is one of the larger models, more like the 180×350 (7×14) mini lathe my other mate bought recently, which seems like a much more substantial machine than Brian's "micro" machine. In fact, I am thinking about getting one myself so I can model away in air conditioned comfort inside the house over the summer. Also, judging by the shine coming off the bed ways in the German modeller's site, the larger Optimum lathes are better finished than Brian's tiddler, or the owner has gone through the process we are at the moment and cleaned them up.

[egaParticipant @ega]

Hopper:

FWIW, I think you are an absolute hero.

MadMike:

I take your point but when someone asks you how to get to Cork it is no answer to say, however justifiably, that you wouldn't go to Cork from here, particularly when the querist has already started his journey.

As MEs we are inclined to fix problems ourselves if we can.

[JasonBModerator @jasonb]

Posted by MadMike on 30/10/2015 09:19:02:

Is it me???

On the 25th August, barely 8 weeks ago the OP reported "……my new lathe arrived….."

So after 8 weeks, or so, 33 pages of messages on here, visitations from that nice "Mr Hopper" and all of the advice given freely and generously the problems with this so called "new lathe" are still not sorted.

Frankly if I had bought a piece of equipment like this and it did not do the job it was designed for then it would have gone straight back to whoever sold it to me. Like it or not it appears to be a crock of s**t, and is clearly not fit for purpose. Please do not try and convince me that, it is only a model making lathe and so we should not expect too much from it, or that it is Chinese and that's what you get for your money, or that because you are in the Australian outback nothing can be done about it. That is all rubbish.

Get your money back and start again. I am stunned that in this day and age nobody has said this earlier.

Sorry to piss on everybody's (possibly everybody's) parade but this product is not fit for purpose.

So as the supplier said the lathe was NOT suitable for use with steel, the fact brian can get a good mirror finish on aluminium and brass but fails misrably to get a finish on steel makes it not fit for purpost does it? Sound more like it is being used for something other than its intended purpose.

[JasonBModerator @jasonb]

Hopper, I think I could find the source of at least 90% of those engines either castings or just drawings.

Yes that is a slightly larger lathe but the question was about a premium brand not a particular model in their range.

[AjohnwParticipant @ajohnw51620]

Posted by Hopper on 30/10/2015 12:21:50:

Posted by JasonB on 29/10/2015 20:43:30:

You only need to look at some of the personal websites of German model engineers to see some very high quality work that they do on their Optimum and Quantum brand machines. Such as this one

Price is about the same as Warco want for a similar 280×700 be it pink or green

Edited By JasonB on 29/10/2015 20:51:59

Some stunningly beautiful models there for sure. I wonder if they are his own design, or is there a whole world of plans/kits on that side of the language barrier we don't see from this side?

Looks like his lathe is one of the larger models, more like the 180×350 (7×14) mini lathe my other mate bought recently, which seems like a much more substantial machine than Brian's "micro" machine. In fact, I am thinking about getting one myself so I can model away in air conditioned comfort inside the house over the summer. Also, judging by the shine coming off the bed ways in the German modeller's site, the larger Optimum lathes are better finished than Brian's tiddler, or the owner has gone through the process we are at the moment and cleaned them up.

There is some stunning work done on all mini lathes of all makes. In some cases it would pay people to fit a polishing mop to one end of their off hand grinder to improve on file and emery cloth work. Not that I;m being cynical of course. Actually a supplier told me how surprised he was by some of the results people get but then he wouldn't be aware of what people do. Neil posted a thread showing some extreme work done on one but he has also remachined some of the bits.

I'd strongly advise people not to get sucked into the .de aspect. On the other hand they do point out that the bed castings for one of their larger hobby lathes are aged for 6 months before grinding etc but I understand traditional lathe manufacturers leave them lying around for a lot longer than that. I wonder if 6 months is sufficient to really achieve anything useful.

The steel cutting problems are probably down to general rigidity – Brian wanting a very light weight lathe. Too light in my view.

John

–

[Brian JohnParticipant @brianjohn93961]

Jason : One salesman said this lathe was not suitable for steel but another said he could not see why steel would be a problem. My inability to get a good finish on steel is probably due to a combination of inexperience and faults with the lathe. This a 450 Watt motor so I would have thought it could handle steel. Let us wait and see what results can be achieved once Hopper has finished adjusting and fine tuning the lathe.

Madmike : I had already sent two Sieg C0's back to a different supplier because they both arrived damaged in transit. One gets sick of sending things back ! Had I not had this previous experience then I might have considered sending the Optimum back to the supplier.

 

Edited By Brian John on 30/10/2015 22:04:05

Edited By Brian John on 30/10/2015 22:04:38

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Brian John on 30/10/2015 09:46:17:

If I had my time over I would probably buy the US made Sherline as they seem to be problem free straight out of the box but they do cost twice as much.

.

Brian,

I feel the need to make one observation:

If you include the value of Hopper's time; I'm sure that your Optimum will have 'cost' far more than a Sherline.

It has been interesting to follow your 'voyage of discovery' … but many innocent purchasers would not have the benefit of a friend like Hopper, and I sincerely hope that this thread will stand as a warning.

MichaelG.

[julian atkinsParticipant @julianatkins58923]

over many years i have always been amazed at the fellowship and fraternity of model engineers. i received considerable help when a 'nipper' which generosity i have never forgotten, and in various ways have tried to do the same within my own capabilities (eg sorting out injectors).

Hopper – you are a 'star', and if there were 'Oscars' for ME then you would receive one!

cheers,

julian

[AjohnwParticipant @ajohnw51620]

According to how the belt is set you have 450w at either 1500 or 3000 rpm Brian. They mention the 450w as input power or as they put it total connection rate. That probably means circa 200w as far as motor output is concerned. It could even be lower as there is no mention of how they have rated the motor. It might well only take that current when it's in the fastest speed setting on either range.

So say the motor is 200w out if you half the speed you have circa 100w, 1/4 the speed circa 50w and etc. This happens because the torque the motor puts out is relatively constant so watts or HP go down as the rpm is reduced.

The Peatol (Taig) I had for several years used a 1/4 hp motor and belt drive. It could easily take 0.1" of 3/4 diameter mild steel with a 0.050" cut and way way more than that off aluminium with a tool ground to remove that particular material as rapidly as possible. That's 1/4 hp out *. I'd say the speed on mild steel was around 500 rpm, probably some what less. In your terms on a variable speed lathe you would need to be in the 1500 rpm range and have a motor fitted with around 3 times as much power output. 3/4 hp nearly 600w out circa twice that in, maybe even more subject to the motor.

Taig seems to have gone variable speed now but not on the UK Peatol site. I assume the unit is similar to the sherline one, spec here

**LINK**

The torque graph on the page needs some caution – note the current and and time limits mentioned. The curve is what happens when the motor is loaded to reduce the speed to the value indicated on the graph.

* At the time they supplied a GEC motor that was probably conservatively rated and it did get very hot when doing things like this but it never let any of it's smoke out. Just a bit of a warm varnish smell for a while when it was new.

John

–

[HopperParticipant @hopper]

Thanks for the kudos, guys. (But let's wait and see what the end result is!) Spent an hour in the shed this morning and took a small scraper to the underside of the carriage and got the ways looking much better. Will post some pics shortly. I am remembering stuff I had forgotten years ago as I go along. Having a great time. Like Julian said above, I too had all kinds of guys help me out over the years so its only a pleasure to be able to pass it on. The vintage motorbike world is very much like that too.

Edited By Hopper on 31/10/2015 05:30:16

[JasonBModerator @jasonb]

It's not just the size of the motor that will make it suitable for steel, things like regidity and overall strength (or lack of) have far more to do with it.

[Brian JohnParticipant @brianjohn93961]

Jason : thank you. It makes sense to me now.

Lathes are like used cars : they do not come with a crystal ball. When you have one problem and you think you can fix it, okay…but then you have another problem… and another… and another ! If I had know I was going to have all this trouble then I would not have bought it in the first place. But having come this far (and learnt a lot) it is worth waiting to see what results Hopper can achieve before we pass final judgement.

One thing I am sure of : nobody else on this forum will be buying this model Optimium lathe .

I am curious about the speed control on the Hafco lathe. It is not an electronic knob ; it is that lever mechanism on the left. I have not seen that before. Is it a gear change lever ? How does it work ?

**LINK**

 

Edited By Brian John on 31/10/2015 07:04:28

Edited By Brian John on 31/10/2015 07:04:56

[HopperParticipant @hopper]

Brian I think that bigger lathe has six speeds and that lever operates either a gearbox or pulleys. Way too much lathe for you boyo.

Anyhow, here a couple of the missing pics from Thursday's measure up, and some of today's effort.

Checking the travel of the carriage against the (relatively) flat glass plate

And the other side, rear bed way

Here we are checking the V way in the bottom of the carriage for parallel to the flat ways for the cross slide above. Precision ground round bar is a Yamaha RZ350 gudgeon pin. Parallels are carefully measured 3/8" HSS tool steel.

And checking the flat way.

Not a bad result on this one. The right hand end of the V way was one thou higher than the left hand end, as viewed in the pic. Flat way was within half a thou – within tolerance. Yay, a first time for everything.

Time to check the sliding ways on the carriage against the bed ways with a thin smear of bearing blue on them. Actually, I had to put a slightly heavier smear than usual to get it to show up in the pics. The normal rule of thumb for fine bluing work is to rub the blue on with your finger, then rub it off again. What's left will do you. Here we can se the carriage is riding on the outsides of the cheeks on the V way and more heavily at one end of the flat way than the other. So by the time I scrape the right hand end of the V way to get it parallel to the cross slide surface, it should briing that flat way down into contact. Sometimes you get lucky.

So first up, a very careful few strokes with nice smooth, worn, file to knock down the high spots and burrs. Then a rub with a small slip stone.

Result! The end of the flat way has come down into contact as required. And a lot of those 'orrible machining marks are gone.

Re-did the test with the gudgeon pin in place etc and got a 0-0 reading on both ways.(Well, close enough for our purposes and equipment here.)

Edited By Hopper on 31/10/2015 07:36:07

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