Member postings for SillyOldDuffer

This thread quotes mentions 0.3, 0.5 and 0.6" of smokebox vacuum as measured by someone called Jim Ewins.

Also "anyone who has more than 1" of vacuum on a 5"g smokebox has something very wrong somewhere".

They recommend an air-conditioning gauge as being easier to mount than a manometer and using an incense stick to detect leaks.

Dave

It's an excellent argument for owning a Myford!

When I eventually got to see an ex-colliery DSG in the flesh I was amazed how big it was. I reckon it would just about fit into an empty single garage, but there wouldn't be enough room to operate it. The chuck was at least 2ft in diameter and looked far too heavy to lift manually. If my memory is right the owner told me the motor took a 15kW 3-phase supply.

I still want one though, just for the bragging rights...

Dave

Edited By SillyOldDuffer on 22/08/2016 17:03:06

That's a very interesting combination. Any chance you could write an article for Neil that covers the pros and cons of the two lathes and what you use them for?

I've had a soft-spot for Dean Smith and Grace since overhearing a chap who owned one slap down a group of raucous Myford fans. About 5 years ago I was in a queue to pay for some bits at the Bristol Exhibition. Three Myford owners were mercilessly ragging a mate about his decision to buy Chinese. Mr DSG turned round and said "I suppose Myfords are OK if you like making toys but the chuck in my Dean Grace and Smith weighs more than your Super..."

I would love to own a Myford in good order but think they are over priced. People buying them just for the bragging rights put me off too!

Dave

I like to provide feedback after asking a question. Firstly the people who offer advice deserve some recognition and secondly others may like to know if the advice helped.

In this case a triple thank you to Jason for providing:

• the link to http://www.modelenginemaker.com. This turned out to be an interesting site that I'd not seen before.
• the link to Stewart's build thread on http://www.modelenginemaker.com. I wish I'd read it before starting my own build.
• a copy of the original, clearer, drawings on dropbox

All of these were useful aids to progress,

Yesterday I assembled the engine to check the fit. I would love to report that it turned first time smooth as silk: in fact the engine has several all too obvious tight spots. The worst problem by far is that the crank assembly is slightly bent, a problem I would have avoided had I made the crank the Stewart Hart way, ho hum. I got away with the "Drill After Assembly" mistake; the crank is bent because an 8mm drill wandered, not because the pin holes are misaligned.

I've a few more bits to make before the engine might possibly run. If all goes well I shall be putting air in it later tomorrow. Fingers crossed...

Cheers,

Dave

"init" is probably short for "initialise" and isn't an error as such.

The persistence of the message may be indicating that the VFD's microcontroller has got stuck doing it's pre-flight checks. It could be that initialisation can't complete because some essential part of the control wiring is missing . Or as Mark suggests it might not be able to initialise with the wrong keypad.

I would try lashing up the control wiring to see if that makes a difference.

Dave

Edited By SillyOldDuffer on 21/08/2016 20:04:03

Edited By SillyOldDuffer on 21/08/2016 20:04:53

TN are mentioned as a maker in this Practical Machinist thread

Just managed to lose a post!

Anyway, Industrial Production in US $ Billions (2013)

China 4008.35
USA 3054.53
Japan 1477.79
Germany 1012.14
Russia 512.31
Brazil 507.67
India 468.14
Italy 446.53
UK 435.54
South Korea 434.88
Indonesia 389.55
Mexico 382.15
France 360.04
Saudi Arabia 358.82
Spain 321.44
Australia 305.36
Canada 230.76
Turkey 207.73
Argentina 138.16
South Africa 106.56

Bear in mind though that Industrial production is not a good indicator of a nation's per capita wealth.

The advantages of concentrated Sulphuric Acid compared with the alternatives are:

• Much cheaper in bulk
• Can be diluted to a wider range of strengths to suit particular needs
• Fast acting (particularly important in Industry)

The disadvantages for hobby use are:

• Ignorance likely to be severely punished
• Lots of 'wrong way round' advice on the web
• Reacts with many household and workshop items
• May be difficult to buy
• Safety issues in use and storage
• Acid proof apron, gloves and eye-protection unlikely to be available.
• May be too aggressive for comfort

I have concentrated acid available but rarely use it. I agree that most hobbyists would be wise to start with a milder alternative unless they know what they're doing and have a good reason for using the real thing.

Cheers,

Dave

Hope this diagram helps. You can measure torque at any distance from the crank because, for a given turning resistance, weight * length is a constant. If length is short, you need a large weight. But as length increases you need proportionally less weight to turn the crank so you get the same answer.

In the absence of a spring balance, position the handwheel at 3 o'clock or 9 o'clock and slowly increase the weight until the handwheel turns.

Dave

I'm sometimes tempted by a life of crime. I'm sure with a little thought it would be possible to make scams like this much more convincing. Fortunately for the well-being of society the thought of prison deters me - I cannot shower with other men.

Cheers,

Dave

PS. Had to look up Mark's "coon ages". My nearest raccoon would be in a zoo, though there are a lot of llamas round here.

You could reduce lift by either re-compressing some of the Helium in flight or by adding air under pressure to the balloon.

I doubt an airship would want to carry a hefty compressor, so increasing density by adding air feels more practical. The Helium could be purified later on the ground, thus reducing losses.

Just guessing.

Dave

Seems you have to spend money to get a copy of BS8888 but this overview looks useful.

Dave

Parting off is such sweet sorrow. 30mm diameter free cutting mild steel, rear tool-post. Dug in and tore the holder. The work and 3mm insert both survived!

That's me stuffed then. I specialise in ambiguous mistakes...

Many thanks chaps - 'Drill After Assembly' makes perfect sense. What a shame I've drilled the holes already: it will be interesting to see how well the parts line up when I try to put them together!

I didn't want to cause embarrassment by identifying the drawing but you've got that right too.

With 47 parts (excluding fasteners), the drawing is certainly very crowded. Where necessary I've dealt with that by redrawing the less obvious parts with qcad. I've found redoing the drawing useful to confirm dimensions and to suss out how to make the thing.

One item of good news about the drawing - I've made well over half the parts without finding any errors.

Looking for answers on the web led me to several different drawing standards. What's preferred by Model Engineers?

Ta,

Dave

My current project has me looking at a drawing that uses a lot of abbreviations. Things like: M3x4DP, 8PF, R30, CS, 10PCD, 3RM and DAA.

These I've decoded, I hope correctly, as:

M3x4DP - Drill and tap M3 4mm deep
8PF - 8mm Push Fit
R30 - 30mm Radius
CS - Countersink
3RM - 3mm Ream
10PCD - 10mm Pitch Circle Diameter

Can anyone help with DAA please? It's applied to some holes.

Thanks,
Dave

But Michael, confusion abounds. Surely PSI is a measure of pressure, not force...

Dave

Sure is. Supported by a grant from the Regional Growth Fund (British Govt) which was cut in the 2015 Spending Review and is unlikely to provide more help.

It will be interesting to see what the government does about the RGF and similar programmes some of which are directly funded by the EU. Will they be maintained?

Before Brexit UK economic policy was aimed at reducing the deficit, which is why the RGF was a casualty of the Spending Review. Leaving the EU opens up the possibility that UK government might be able to support industry more than is already allowed by the GBER, but one has to wonder where the money will come from. This must be a concern to a government previously committed to reducing public spending, and one generally in favour of market forces.

Higher taxes and more borrowing are the most likely way to raise the cash if government decides to support industry more. PFI and PPI deals are a possibility but they have some serious disadvantages. I think it unlikely that significant private money will come to the UK until investors better understand the likely consequences of exit.

Although the company has a German parent, it appears to be half British.

Dave

Edited By SillyOldDuffer on 15/08/2016 22:42:58

Oops, sorry! I over-focussed on the IKEA joke.

But do you know why metric preferred clearance holes are bigger?

Ta,

Dave

I hope someone who knows can tell us. My guess: general purpose metric fasteners have head and nut dimensions specified to reduce the risk that they'll get chewed up when used in average applications.

Dave