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Dean W:
Nice looking oil cup, Nick. One more to go? Double the fun!

Two things for your focus problem.
1) Push the button on the back of the camera that has an icon that looks like a tulip, or that says "macro".

2) If it won't focus on a small item, put your finger or something like a small rule next to the item until it says it's focused.

3) Don't use the flash unless you have too. It blows out small bits, and makes them look out of focus, even when they're not.

4) Check the shot after you take it to see if you got what you want.

Okay, that's four things. Toldja, double the fun.

Dean

NickG:
John,

I think a lot of people use hand reamers in the lathe, why is it dodgy? Do you mean there is a safety issue? If so I won't be doing it again. I ran the lathe speed very low and held the reamer with a tap wrench fed in with a reolving centre to let it float. I've seen this method used a lot in magazine articles in model engineer and such like.

Wes / S / Dean, thanks for the advice. Mine does the same when focused with the green box. I did have macro engaged, it's got an intelligent auto function that basically sorts everything out for you, or is supposed to! It did engage macro but I also had the flash on, I have a light over the lathe.

I tried a few times but not without the flash so I probably need more light and no flash. Will try the something else to focus on trick too. I may need to go away from the fully automatic mode.

Here it is:

http://www.panasonic.co.uk/html/en_GB/Products/LUMIX+Digital+Cameras/Super+Zoom/DMC-TZ6/Overview/2032514/index.html

Nick

NickG:
Quick update, not a great deal of progress but worth mentioning.

I started by taking a couple of snaps of the simple jig I made to drill the holes as promised. It's not really the best jig, all it does is fix the radius and concenter the cover and cylinder. The rest had to be done by eye on markings on the cylinder cover just by gluing the cover on and rotating the cylinder. Seems to have been effective though and worked well.

I then wondered which part to make next and pontificated on a number of methods. I had some brass large enough and enough to do 2 flywheels, also had a bit of steel to do another 2. Then I found some brass 1/2" plate which I could have used. Or, some 2" steel which would make them 1/8" under size.

Anyway, whilst on the netti, I came to the decision to use the 2" steel as I would have little or no OD turning do do if I could drill centrally, just a bit of a polish up. I decided I wouldn't pussy foot about and would try to part off the blanks from the stock. So I went out full of enthusiasm, set the parting tool to the minimum overhang that would do the job, selected a suitable speed - very slow, back gear engaged, about 70 odd rpm, slowest cross feed to keep it nice and constant and even got ready with some suds in a syringe.

Then disaster almost struck - before I could react, this happened: :doh: :(

I’ve moved the saddle a bit in that photo, the blade dug in shattered, and sounded like it hit all 4 walls, floor and ceiling but luckily missed me.
This was my thought process immediately after switching power off:

1.   Oh ****, ******* ********.
2.   I’m ok.
3.   That could have been worse.
4.   Actually I might have mangled the chuck and caused damage to the machine.
5.   I think I might give up this hobby.
6.   Take a step back and calm down a bit.

Seriously, it scared me. I’ve never parted off anything that’s steel as the feeling I get and noise have always put me off. This time I went for it as I thought I was being soft in the past, I thought I was doing it correctly but obviously not.

When I did calm down there seemed a tight spot on the chuck jaws, something has probably got bent. I took the jaws out, cleaned and reinstalled and it works, but there is a slight tight spot at some point so I must have done some sort of damage. It still grips and seems concentric though so hopefully I’ve got away with it.

Here is the damage to the metal:

There are a few major safety points that should go without saying:

1.   Always wear eye protection – make sure you have eye protection you can see out of and are comfortable wearing and make sure you always wear it. I could easily be lying in a hospital bed wondering if I’d ever see again rather than writing this.
2.   If in doubt, stop, I had a doubt in my mind I would be able to part this off but was trying to save time. I should have reached for the hacksaw at that point.
3.   If you have a chuck guard you should probably use it. That piece of steel very nearly came out of the chuck – at the speed it was rotating it wouldn’t have been flung and I’m not saying the guard would have stopped it but it could only have helped matters. I’ll be using mine more in future that’s for sure.

I didn’t think there’d be an issue with me gripping on the threads of that bar, but with hindsight it may have been part of the problem. They were probably the weak point, deforming and allowing the stock to move. :hammer: I did consider turning a parallel section to grip on but then I thought, it’ll grip tight on the threads and they will probably let the chuck jaws dig in a bit and get better grip.

So, I’ve calmed down a bit and the following hour and a half was spend with the hacksaw for punishment – aching now! :lol::

I did face the stock between each hack saw cut so at least 1 side of each blank is faced. Got a nice finish using the suds too, very good.

I could have not mentioned this mishap but I think it’s worth sharing these near misses just to give people a prod and make them think about things twice.

Nick

Dean W:
A nasty bit of trouble there, Nick. Sorry to see it happen to anyone, and especially such a nice guy.

I hope you will take my comments as just a few remarks from a fellow machinist impersonator, with a fair number of this type of job behind him. (Even when I got paid for doing it, I felt like an impersonator!);

The piece was sticking out of the chuck quite a long way. Parting off puts more side pressure on the spindle/work/work holding device than almost anything else, other than knurling, and maybe running a profile tool into the work.

Not knowing the size of your lathe, but getting a sense of scale seeing that you are cutting 2" dia steel, this may have been too much for the lathe in the first place, but there are some things that would have helped prevent such a violent outcome.

First, since the pieces would have a bore in them anyway, it would have been a good idea to put a center in the unsupported end. You shouldn't part off completely with a center in the tail of the piece, but you can do about 80 percent of the job that way, and finish with a saw. The reason not to do it all the way through is the piece will pinch at the end of the cut, causing a similar problem to what you have here.

Second, having the parting blade stick far enough out of the tool holder to make the complete cut is trouble. They wobble like a noodle, and if you had an inch and a half sticking out, it didn't have much of a chance.

Finally, just too much sticking out of the chuck. That far out, and the effective runout of the spindle is magnified. The work deflects a few thou, and again, the tool gets pinched, and pop!

This is one place for sure that you need plenty of lube, too.

Parting off is kind of a tough operation, especially when you're just getting to know the procedure. Don't let it scare you off, though. It's a normal shop op. Find some smaller diameter pieces to practice on. Put them in the chuck with only enough sticking out to get the tool to the cut off point. I would think some size that will pass through your spindle would be a good practice size, and try some leaded steel if you have it. Lots of lube and a very steady feed will do it.

Very glad there was no bloodshed associated with this, and I hope it doesn't put you off this type of operation.
It's meant to be done, but it does have to be sized to the size, weight and power of your lathe.
Glad you got the job done, and thanks for showing us some more progress. I'll bet your poor arm is just drooping!

Your camera;
"it's got an intelligent auto function..."
It will most likely do what ever it wants at that setting. Put that thing into submission. The folks who program these functions think they know what you want. They are often wrong.

Dean

Darren:
Nick, if I remember rightly you have a Harison 6" (12" swing) lathe?

This should have coped with parting this piece, except you would have needed to use a tailstock center as that part looks to be 6" long? The treaded end in the chuck prob made it unstable.

This is 2" diameter and very tough steel

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