Member postings for john halfpenny

What nonsense Ady, but then you never owned one. Perfectly good small car (for its time). We had four in our family. Cheap reliable transport in our extensive experience; it ticked all the relevant boxes, and saved the company.

Not waxing; your dpf is blocked because the exhaust stream is not getting hot enough to burn off the deposits. Italian tune-up will do the job

Edited By john halfpenny on 20/10/2020 22:24:23

Also Warco WMT300, Sealey SM27 & Smithy CB1220 (USA)

I learned on a 1936 Lichfield 10. Clutch control was quickly mastered as the self-starter was not working, so a stall required hand cranking. My first car was an MM Minor with the side valve engine. I bought an overhead valve conversion made by Geoffrey Taylor of Alta racing cars. Regrettably never fitted due to the demise of said Minor, and sold on to a man from Liverpool whilst on a visit to Salford University. I believe it would cut the 0-50 mph time from 32 to 18 seconds. (0-60 could not be quoted for the standard car).

Great video, not seen that before despite owning pre-war Ford's for 40 years.

In our damp uk climate, water condenses on the fins as heat is extracted. In cold weather, that water freezes, and to combat this our ashp reverses occasionally for about a minute. Warm water at 30 deg is sufficient to melt the ice which runs down to ground level. In our case, no provision for draining that water away was provided, so it freezes again, and over a few days the ice can build up. Of course this requires sustained air temp of below 0deg, which we seldom get for long. No harm caused, but I recommend some deliberate means of directing the melted water elsewhere. COP is of course dependent on the temperature difference across the heat exchanger, and accordingly varies significantly with ambient air temp. We run at night, so COP is low, but it doesn't matter because electricity is cheap - my point being that COP is not the sole governing factor. We also have a huge mass of concrete as heat store (not very green I know) which keeps the internal temp very stable.

BTW, anyone reading this thread must distinguish between air/air ashp which provides direct warm air, and air/water ashp which provides warm water for underfloor heating.

Edited By john halfpenny on 09/10/2020 21:35:11

Steve, we have had a Mitsubishi ashp ( made in Scotland) for over 10 years, in a new build 350sqm house, with concrete floors up and down; 30 deg for heating and 55 deg for hot water. We are very happy with it, no maintenance to speak of, and current electric bills (that's everything) of around £1400. We got all the certificates, and the government pays our bill for 7 years under the rhi scheme. The system is slightly under specified because I didn't want 3 phase costs, so we use a wood burner to give direct heat when temp is below 0deg. The system works well above an air temp of 5deg, but below 0deg, it's just an immersion heater - cop of 1. We find it most economical to run it on economy 7 tariff at night only, except on the very coldest days when we may run for a few hours in the day as well; internal temp is typically 21deg. The air at night is of course colder than in the day, but night electricity is cheap, so the arrangement works for us. Most of the time we are only 2 occupants, so we use the zoning to turn off active heating in unused bedrooms. Noise from the fans is unobtrusive, but we are on a big plot. The system occasionally reverses in cold weather to melt ice away, but ice does accumulate around the base of the unit - this could have been dealt with on installation if the problem had been appreciated. Plumbers are generally useless, as are electricians; they don't understand the technology, - our one problem was quickly addressed and solved by a local air conditioning business. A good choice if you already have underfloor heating. I'm sure tech is better now.

I understood there are three(ish) practical reasons in real life:

No wear on the stud/casting threads, and easy replaceability of the stud.

No risk of bottoming out the bolt in the threaded hole.

Consistent nut torque, owing to the unvariable thread length engaged between stud and nut (40% being thread friction)

The Birmingham beam engine is on the island at the centre of Dartmouth circus, where the Aston expressway goes under the Middle ring road. Not an easy place to stop!

Get a gallon of brake cleaner and a pump spray bottle. Despite its name, it is a great cleaner and degreaser, used by most commercial garages, and relatively benign.

Dr Johnson of Lichfield.

'Bostin' is yamyam not brummie, but in brummagen it's definitely 'orstin', or so my Longbridge apprentice mates would say.

Edited By john halfpenny on 30/09/2020 20:06:08

Patent documents can be a good starting point. Be aware, however, that whilst everything written in a patent document must be true, the whole truth is not a necessity. Likewise, the necessary features must be shown completely, but other related but inessential features may be omitted, to another scale, or adjusted to avoid disclosing helpful aspects unrelated to the invention as such. I would always take care, especially with seemingly detailed drawings of which the victorians were great exponents. (Speaking as a 40 year veteran of this stuff)

Can't we agree that the tang can serve both purposes. I was taught that the taper should be enough for drive, but clearly some machine tools use the tang (also).

Morris were notorious pre- and just post-war for using metric threads with imperial heads, owing to the parsimonious Bill Morris acquiring some metric threading tools with the Hotchkiss engine plant in Coventry.

I have use them for years as jack packers on my car lift and trolley jack (in a sensible and appropriate manner)

And Virgin 'upgraded' me last year from payg to a monthly contract. They took my balance without asking to pay tge first mon the - theft by another name. Needless to say I am no longer a customer.

Or use a cycle computer. I have an £8 one. Set the wheel size as 1667mm, and the km/hr display is an analogue of rpm - ie for 24.4 km/hr read 244 rpm. The pick-up is small enough to put just about anywhere accessible on the spindle. A bit of maths on wheel size will accommodate a reduction gear.

Edited By john halfpenny on 10/08/2020 17:33:37

Nevertheless Dave, we cannot all wash each others windows.

Have a look at Iter site tour videos on you tube. The latest, from a day or two ago, shows the massive engineering effort as assembly starts. The magnetic field confined within the Tokamak is alleged to have power sufficient to lift an aircraft carrier. I can't help thinking we shall more likely rely upon windmills and solar panels.