Member postings for Roger Best

quick positive comment:

I found, when trying to measure some threads on my lathe, that if I took a high resolution photo of the thread with a tape measure lying along it, If I zoomed in on the picture I could measure the features far easier than I could by eye. It seemed to be adequately accurate too.

If we are just talking about a tensioning knob between those forks it looks an easy job.

Sorry i can't post anything over as my lathe is out of action.

Great start.

Another good advert for not buying someone else's mistakes.

That's a fabulous bandsaw, it is very reminiscent of early 20th century steam toy accessories and very different to my 60s Italian bandsaw which uses a heavy pressed box construction.

Either way its well worth some TLC and possibly some sensitive technical enhancements.

My Grandfather made Sunderland flying boats during WW2, he is is described as an aircraft carpenter on my father's birth certificate and made Sunderland flying boats. He made a good few patterns and jigs and was very proud that some had to be accurate to a thousand of an inch.

I reckon they could have slackened that tolerance a bit, but who am I to know, all he stuff I designed sits on the floor and the Sunderland has an excellent reputation.

Genius!

Programmable, Slick mechanism that must have taken some serious ingenuity. Amazing.

I skimmed through the notifications trying not to get irritated by a few provocative comments, and I now find some very good essays here on the thread! Looks like this topic has got people going.

Its great to see that people appreciate that CAD is an opportunity to be creative, and 3D printing allows a lot of creativity. Its real engineering, by making super material-efficient shapes you can make amazingly strong and light structures, ideal for aerospace and satellites.

Its also great for modelling as numerous n-gauge modellers have demonstrated.

The very exciting stuff, using metal rather than plastic, is still a bit expensive for home use but its out there.

As eloquently stated above you shouldn't decry it, its not easier just because its not a traditional craft, its just different. That is as rude as a person looking at a prize model steam engine and saying that it was easy because the technology was centuries old and the design was copied from the original.

This is just for impulse buys for those who turn up.

Screwfix is set up for people who buy loads of stuff at a time.

My professional specialism is Nuclear crane design, so you would have thought that I would have something useful to say about design codes and standards.

Not a hope.

They are written by committees, so satisfy no-one. The committee rarely wants to take full responsibility so they leave lots to the designer, and its usually impossible to correlate between a prescribed design feature geometry, a degree of stress and the probability of failure.

At best any design code is a hint of Relative Good Practice for the observance of idiots to reduce risk to the public.

Its great to see people talking about FEA and parallel calculations. That way any anomalies and errors are likely to come out.

One more point, you need a four times safety factor against failure for good safety in a variable load environment. Buildings can make do with less as their self weight is the dominant load. Aircraft fly with this sort of factor to allow for a blustery flight. A 2X hydraulic test should be well away from causing damage if the design is that sound.

Great progress Dr_GMJN !

I have been involved in a number of structures that where grouted in, similar to using a liquid shim as discussed.

The general rule was to use a jacking screws to align the items preloaded against the hold-down screws, then flood the joint and tighten to the specified torque.

The large area of the plates gave huge stiffness so it doesn't matter much what grout you use but big stuff tends to be cementacious as its dirt cheap. However epoxy is a good vibration absorber, so reduces chatter and is cheap in small quantities.

If your wedge-shaped gaps are still a problem I am sure something could be done along these lines.

Cool thread.

There are lots of lessons here, meddle and there are consequences, even to simple actions.

I also live in a glacial-clay valley in the middle of chalk downland ironically, Several properties nearby have suffered subsidence and a stream runs under my house. Fortunately my footings are under the water level, so consistently soggy, even in summer. Its the change in resistance of footings that causes subsidence as we found in our first house.

To answer the first question, yes we need to be improving rivers, even though it will be expensive. These wet winters are here to stay for a good long time, and flooding will be common. So we should seek sustainable solutions and make our environment resistant to lethal flash floods too.

Its not quality that is the main difference but beefyness, the 2.7 is a beast in comparison, so capable of much heavier cuts or greater accuracy at a given cut size. The bed size and traverse is usefully bigger too.

Both 2.7 variants are very useful machines. Although I chose an alternative it is this size and I am very pleased with my choice so far.

It is very much a first-off. There has to be a good bit of process development and "does it look right". In such a case three attempts is good. many people need three attempts to make a part with full instructions and published tips.

That's a useful principle, thanks, you only need the facets you need for a job so a jig is easy.

Fascinating.

Put a ruler in the photo or a tape measure, that will help.

If he had it in 1966 then it may be asbestos. best leave alone until you are ready.

Cheers

Rog

Looks like it has come off the surfaces and something is stuck underneath - the gibs maybe.

Strip it down before you bend the leadscrew.

These systems are over 50 years old, a sign of quality that we struggle with nowadays.

I recall that the dash for gas was a big investment too, that reduced acid rain so it has some purpose even if we still needed to invest in wind afterwards.

My favourite is tidal flow turbines, i.e submerged turbines with no barrage. There is flow somewhere around the UK all the time and the moon is pretty regular. No calm winter day worries.

Thanks for the question and comments.

I was looking at sets for Christmas but gave up, i couldn't imagine what I wanted all those bits for and how I would want to set up parts and I don't want to "invest" in stuff that takes up space for a few decades.

I did note that pairs of parallels are readily available and sets are not a massive discount relative to buying pairs, so I decided to wait until I had some jobs identified.

One good tip on Blondihacks was using a long precision bar to set up the vice. So I guess I need at least one pair.

Great thread, I remember bing in this situation, those little cylinders don't last long.

Two solutions:

Firstly as stated above, cut them up, and chuck them in the general metal scrap bin at the tip if you insist they are not useful steel.

Second solution to further issues, get a gassless MIG. Amazing machines, far easier to use. The mess I make is no worse than the mess I made with a normal MIG.

that looks great.