Member postings for Siddley

The missis is leaving her laptop here and it's got a built in webcam - maybe I could do a live Christmas 'webcast from the workshop' so people can watch me getting my finger caught in the belt sander and drilling holes in the wrong place

Just kidding

That's great advice. No matter what kind of engineering you are planning to do Lee, you can't have enough tooling.

Feliz Navidad a todos

I'm spending Christmas on my own, my wife is visiting her family in the UK. Still, I have four cats and a Rhodesian Ridgeback dog to keep me company...

Hello Lee - I've only been here about 6 weeks and I'm glad I joined. The depth of knowledge here is incredible.

I wouldn't be in too much of a hurry to take a scraper to your new lathe. I'm not familiar with the Sieg lathes, but my X2 mill didn't require anything like that. Scraping surfaces so they are both flat and parallel is a skill that'll take you a fair old amount of time to acquire. It's especially tricky on a machine tool because you can't just plonk it on a surface plate

Did you mean frosting rather than scraping ?

Please take it as a compliment Alan, that's exactly how it was intended. I don't doubt the stepperhead is a superb machine tool. I'd like two though - one to use and one to keep in a glass case and just look at

Dias - I'm a long way from Portugal, only 70km's from the east coast of Spain. It would be too far to drive. Thanks for the thought though

Clive - Great little machine you have built there. I don't have a foundry nearby but there are a couple of companies that sell structural steel sections. I'd love to read your build article, I would have thought it was exactly the kind of thing MEW should be featuring. I don't know how quickly I'll get to start  building a lathe, but I have to take some design decisions in the next few weeks as I've got an opportunity to get a shipment of tools and metal from the UK, to include the gauge plate I'll need and a lot of other parts I can't source easily here.
Would any photographs of a commercial solar tracker installation help your new project ? - the reason I ask is that I live right next door to a 'solar park' which has probably a hundred of the things !

Edited By Siddley on 22/12/2012 13:36:53

Terry - I've read the Gingery book, but it's the castings that put me off. I don't feel up to the learning curve at the moment.

JD - Thanks for the comprehensive input, I take your point about steel maybe being better for the base. Industrial lathes here are crazy money compared to the UK, probably the high cost of new lathes keeps secondhand prices up. I have been offered machines which you literally couldn't give away in the UK for bargain sums like EU1500...
A Boxford would be great ( I had one in the UK and agree with you 100% on Myfords ) but I doubt I would find one at a sane price.

Pete - That's an interesting link. Looks a bit 'expedient' at first glance but I've downloaded the plans to check out later.

The stepperhead isn't a lathe, it's a work of art - it reminds me of a really high end hi-fi turntable more than a machine tool...

The pictures of the Hubert Elffer lathe are very useful, did Mr Elffer ever write an article on how he constructed it ?

What with the cost of machine tools here in Spain - a lowest common denominator Chinese mini-lathe is about EU 900 - and the limited capacity of my Emco ( sorry little Compact 5, you are quiet and very accurate but you are too small ) I'm thinking about building my own medium sized lathe.
One which incorporates the features I need and the ergonomics I prefer.

Has anyone got any interesting links to similar projects ?

Just off the top of my head I'm considering a honking great slab of gauge plate for the bed, attached to a steel or aluminium base which is then filled with epoxy concrete.

Compressed air ( or any other gas ) is potentially an enormous hazard - I have always had a very healthy respect for it - but I don't think it's too dangerous for a non-professional to work with if they research the subject and follow the right design procedures.

I used to build silencers for firearms ( legally ! ) and the pressures inside a 'can' ( as we called them ) are an order of magnitude greater than the ones mentioned here with the larger calibres of weapon. Sure it's a brief spike - the can isn't closed, obviously - but it's still a lot of gas energy to restrict.

Aluminium, stainless and titanium are all suitable materials if used correctly, although aluminium cans have to be designed carefully to avoid 'flame cutting' by the propellant gasses.

What I mean to say is that it's do-able ( high pressure gasses ) as long as you get clued up and follow good engineering practice.

Clive - my mate was the commander of an M109, I'm sure he thought he was Rommel :D

Is there a really compelling reason it has to be aluminium ? Precharged pneumatic air rifles have reservoirs much the same length and O\D you specify and are safe to about 250 bar depending on the model. Many manufacturers sell the reservoirs as spare parts. I'd just buy one of those assuming them being made of steel isn't an issue.

I do wonder if many of the problems I had with the scales were related to the poor fit of that connector. It wasn't anything like the ARC version, but was similar to a telephone jack, except with 4 wires and smaller. I had to trim the crudely shaped connector to get it to fit and then seal it in place with silicon ( after providing strain relief )

If ARC have solved the issues with cheap scales then it's got to be a good thing.

Sorry for not replying to your message, life has been crazy here over the last week - preparing for my wife to visit her family in the UK, one of our cats broke his leg somehow, had to rebuild the flue for the log burning stove ( again ) - I simply forgot

Feliz Navidad

Have these 'DRO's improved recently ? I tried using the cheap scales and readouts about 5 years ago and had endless trouble with them, such as :-

Connectors from readout difficult to fit to scales and insecure.

Scales sometimes 'froze' and wouldn't start working again until the battery was removed and replaced

Update rate on the scales was very slow, it was neccessary to crank the wheels on the machine in a tortoise like fashion to avoid overshooting.

The 'off' button on the scales was really a 'standby' button and the battery was still being drained.

General 'glitching' from display and from scales - blank readouts, refusal to zero.

I should point out  I didn't buy the scales or displays from ARC
I gave them away to a friend eventually saying ' here, see if you can make these work, I give up '

Edited By Siddley on 20/12/2012 13:52:16

Castrol R gums things up really badly if they aren't actually moving, it leaves a really nasty varnish like deposit which is murder to clean up. I used to curse the stuff at times, cleaning it out from carburettors on 2 strokes that had been standing for a while.
Does smell....evocative though

I've got a feeling that the change gears on the CL500 are a bit bigger than that, sort of Myford\Boxford size, but it's a long time ago so I can't be sure.

Yep, it'll end up looking like that boiled sweet you put in your pocket when you were a kid and found a week later

They aren't the easiest machine to screwcut on - the lowest speed is a bit fast and there is no thread dial indicator so really you have to keep the halfnut engaged and reverse the motor after each pass.
I had a CL500 years ago and hated it to be honest, but if you bought it cheap then what the hell ? go for it and the best of luck to you.

Isn't there a sticker on it somewhere that gives you the tooth numbers of the change gears ? I'm pretty sure there was on mine. It's got to be in the manual or the parts list. That will get you halfway there.

If you only want power feed I'd be tempted to take a different approach and power the leadscrew electrically.

Matrix transformations ? blimey I tried that years ago and never got past the first hurdle, they gave me a migraine A man's got to know his limitations and maths is one of mine...

I had a really good book about great British engineering achievements ( can't remember the title, something about boffins, or backroom boys ) and I was initially a bit taken aback to find the story of 'Elite' in there together with Concorde and Blue Streak.
Software is engineering of course, but a computer game ?
But it all became clear as I read, those guys really pushed the boundaries of what was possible with such limited hardware.

I've always used any oil that comes to hand, as long as it doesn't gum or evaporate. It's not caused any problems, but the case for using a 'proper' oil as explained by some of the people posting above seems pretty convincing. I think I might change my ways ( ways - Geddit ? )

As someone who has spent 90% of his working life either spannering, machining or bashing metal about in one form or another I find that comment a little bit insulting. I bet you were a bag of laughs on the 'shop floor'