Member postings for Robert Dodds

Chris,

The 60 deg dot punch is sound advice but on occasion I have added a scribed square box at the hole diameter so that you have a witness of the hole and if you just get the drill point to about 3/4 of your size and check you will see if the drill has wandered off.

My solution to correcting this would be to gouge a couple of grooves down the side of the hole that I was on with a sharp diamond point chisel, the grooves being on the side to which you need to pull the drill towards. When the drill is repesented to the job it will tend to cut heavy on the side with the grooves for a few moments and draw the centre over. It might need a bit of practice to judge the amount but it can save scrapping a cherished bit.

Bob D

David,

You are confused,

see this BBC quote :- http://www.bbc.co.uk/news/uk-england-sussex-15985711

Workers in West Sussex spent a year on a project before discovering they had helped make the 2012 Olympic torch.

Staff at Best Electroplating, in Crawley, were simply told "a client" had commissioned them to gold-plate some aluminium samples.

After a year, workers were asked to sign a confidentiality agreement by the International Olympic Committee.

There are other BBC reports of torch manufacture in Birmingham and West Midlands

Don't hold out much hope of getting approval to copy it on the Open Source Project

Bob D

Edited By Robert Dodds on 20/05/2012 17:50:25

Springbok Bob,

Thanks for the age compliment but I might give you a year or two. I too am appalled by the avarice of some people

I couldn't find the tongue in cheek smiley or I would have included it in original post which was truly intended as a comedic comment that would be understood by the majority of shop hardened engineers.

Ian,

I suspect the reason for one to each bearer was part of some "Job Creation Scheme" set up by one Quango or another (Tongue in Cheek Smiley)

Bob D

Hi,

Only go for those that include the uniform.

Just imagine going round the club track wearing the white suit and testing whether you can go fast enough to dowse the flame. Got to be worth £150K.

Can you re-light the flame off a 31/2" Tich?

Bob D

John,

Have you seen

http://www.modelengineershow.co.uk/editorial/page.asp?p=662

Although dated 2011 it may be the start of 2012 list but see contact to Duncan Armstrong at MHS on the same page. He Should know

Bob D

Bob,

It's a wet Sunday and for want of something else to do I went to check out where Chubb were being made only to find that their opening line is to deny any connection with locks or safes in the UK . Its all owned by some Assa Abloy oufit and then, Lo and Behold, I look up Yale and they too are owned by the same Assa Abloy along with Union and several other brands.

Can you trust the name you see on anything nowadays?

Bob D

Neil,

The era I was thinking about when limited tools were needed was spanning the 30's to 50's when the model Y and 7Y with 933cc and 1072cc side valve engines were the popular car of the day. After that it started to go down hill and I had abandoned Ford after the Mk 3 Cortina in favour of Rootes Group models which offered much more comfortable leather for your money than Ford did.

Bob D

Keith,

Thanks for that link on the MGs. Perhaps Cyril was closer than I thought when he called them 1/4" Metric!

The bit about the origins of SU carbs was worth finding as well.

Gordon,

I can't agree completely about the assorted tools on old uns.

I was raised on Fords and although I don't remember the exact detail I believe Ford only supplied 2 spanners, a plug spanner and a wheel brace on the end of the starting handle in the tool kit but claimed that you could do a full engine strip without any further tools.

I'm sure somebody will be forthcoming with the detail

Bob D

Edited By Robert Dodds on 20/04/2012 17:57:44

Alan,

The old Moggies sure had a different thread but my father in law, who spent a lifetime in the motor trade always told me that Morris, and for that matter Wolseley, nuts and bolts were 1tpi out to British standards in order to boost parts sales. If you stripped a thread or lost a nut it was off to the Morris distibutor for spares sold at a premium. Gold plated Daimlers that Lord Nuffield ran around in didn't come cheap.

Mind you, Old Cyril always referred to M6 as 1/4" Metric and M8 as 5/16" Metric. He never really accepted the need for another thread.

Bob D

Len,

When Joe was busy sketching his ideal thread we were not talking to the French, we couldn't understand the Swiss and the Americas were still overrun by buffalo so he had it all to himself for years. Then along comes communication and globalisation and we find all these variants.

The problem with threaded parts is that they last too long so we can never get to a point where a particular thread can be cast into the abyss. Somebody always comes along and wants one more nut or screw to finish his refurbishing job!

Hence today we have 47 thousand different threads scattered round the world and none that can be forgotten and only a very few that can even start to interchange with each other.

It nevertheless keeps many thousands employed

Good eh.

Bob D

Brian,

The photo does not particularly highlight it but the angle block is really two plates bolted together.

OK the surfaces are ground up on a surface grinder and the edges of the plates are ground square too so it bolts up pretty accurately.

In use I prefer to work within the support rather than outside it as it much more stable that way round. Most times the mass/inertia of the angle block is enough to let me just hold the work steady on the drill table but I do have a niffty toggle clamp that I can use to clamp the whole angle block if necessary..

Bob D

Peter,

I think your two tone yellow might confuse some into thinking its just a little boss thing.

It's part of the main casting however, that bolts to the lathe bed and will need some reinforcing.

I'm not sure of the detail of the casting on the underside but my starting point would be to see if a 12mm strap of steel could be permanently bolted accross the whole mounting face replicating the mounting holes and then cut off this weakened lug.

You could always try for a 2nd hand one from a site like this. Amazing what comes out from under the bench

Regards Bob D

I too see the new posts with photo detail. How many of those bolts are attachment bolts? Are some just used to jack off and align the base to set it up square. It might suggest that the whole thing has been a bit brutally tightened at some time.

The basic repair principal is still valid.

Bob

Edited By Robert Dodds on 17/04/2012 16:56:46

Hi ,

Like so many others I love my toolmakers clamps but my favourite was inherited from my father, a WW2 toolmaker, He made this in the 1930's so its stood the test of time. It forms an accurate angle block and can be used in at least two aspects, sometimes three depending on the component size.

I hope the three pictures illustrate it's construction and at least some of it's uses.

Bob D

Edited By David Clark 1 on 17/04/2012 12:44:29

Andy

My guess is Universal Bright Alloy Steel as opposed to Universal Bright Mild Steel.

The term is still used and leads to low/medium carbon steels like En 16T at 0.35% C., tough and case hardenable so would probably suit your application.

Bob D

Hi Chris,

I've just rechecked my plans for Elmer's tiny and there are 2 versions. The original quotes #57 drill (0.043) for the port holes but the later amended drawings call for 0.063 holes.

This might make your task a little easier. I would support all the earlier advice and perhaps note that the small hole to the tapped inlet should be drilled before the tapped hole and so avoid breaking through on a curved surface with the smallest drill.

Bob D

Hi,

As an apprentice I took Heat Engines as part of my HNC. Didn't do particularly well at it but I'll never forget the " Steam Entropy Tables" that we had to resort to to work out the power output from steam engines, turbines etc.

Its somthing to do with the energy of the water molecules in addition to the energy from the compressed gas that makes performance on steam so different to performance on compressed air .

There's a lot written on Google about Entrpy of Steam and I still can't get my head round it!

Bob D

Dias Costa

Your description of your sink leads me to think you have a Belfast sink, see google link below.

Twyfords, one of several makers, claim that they are impervious to stains and chemicals and only require soft cloth wipe down etc etc.

Sink Link

Consider returning the sink under complaint and what about keeping your hands out of the metal contaminants by wearing disposable gloves. It could prove that the staining is from your water supply or cleanser!

Bob D

Edited By David Clark 1 on 15/03/2012 09:30:29

capnahab,

There is little mention at present about checking the effective thread dia. Using three equal small wires you can mic over the original one and then repeat on your new one .

It seems from the photos that your new thread is sharper crested than the old one and that might indicate that you need to go deeper or widen the thread.

Another quick way to compare the 2 thread forms is to lay the two threads together against a bright sky. This would confirm your TPI and give some indication about the match of you thread profile.

As a rule of thumb you don't often find metric threads mixed with imperial dimensions. A check of the surrounding diameters and lengths will often confirm which you are dealing with .

Bob D

Bob,

Not exactly a solenoid engine but this 13amp plug engine is fun to build and is readily built from the bitza box.

Full set of plans are here (and lots of other qwerky bits too)

http://www.john-tom.com/MyPlans/SteamPlans3/13AmpPlugEngine/13AmpPlugEngine.pdf

I was amazed at how many variants there are in the humble 3 pin plug!

Bob D

Kwil,

I know what you mean but by the same token I work with women every day but I've never understood them!

Bob