G8RPI

Mortars most certainly are covered by section 5, see http://www.legislation.gov.uk/ukpga/1968/27/section/5 " (ae) any rocket launcher, or any mortar, for projecting a stabilised missile, other than a launcher or mortar designed for line-throwing or pyrotechnic purposes or as signalling apparatus;] " People have been locked up for having a used LAW launch tube dispite it being less of a weapon than a similar length of 2" metal pipe.

Out of interest I looked into the "training" requirement and it appears to be up to the suppler to satisify themselves the buyer is adequately trained. If you ae only buying the one type of device and they have avised on the installation they may consider tht enough. If you want a safe firing circuit I can help with that as I've done it as a small part of my day job. Robert G8RPI.

Putting a maroon in the breach end effectively loads the gun so not sure about legality. Wells firewooks came up with a 3 shot conversion for a Churchill that ws muzzle mounted and look like a better idea. http://www.wellsfireworks.co.uk/mines-1/ They also do a canon maroon designed for use in proper gun barrels. They are T2 so you need proof of training but I'm sure they can help you with that too.

Back to original question, there was a Bren at Cambs Lock Antiques Centre in Huntingdon about a year ago. It's individual booths so you would have to go and have a look. It was downstairs IIRC.

Very old post, but if you still need info on the Trimble let me know. Robert.

It's a Kerosene burner No11 according to the image title 😉 Robert G8RPI

Good question. As far as I know there was no easy disposal route for Radium (it's 226Ra to be precise) in th UK. Other common radioactive materials in this sort of quantity can be disposed with regular rubbish, but NOT Radium. It emits gamma radiation and even this small amount might trigger a radiation detector as fitted to many waste disposal sites. If there is no chance that you would be considered a business (and thus charged) you could try asking your local environmental health department.

Hi, It's a 500uA meter so would need a resistor of around 30,000 Ohms (slightly less because of the meter resistance) to read 15V full scale. If you managed to connect it to a 12V battery you will have destroyed it if it was not already faulty. Note that this meter is radioactive. It has small dots of Radium luminised paint on the pointer and dial. These are the little brown blobs. They won't glow in the dark anymore but are still radioactive. It's not particuarly hazardous unless you open it up or sleep with it on your pillow.

Fitting LED "replacement" lamps (bulbs) into lights that were designed for filament bulbs has a couple of issues. Firstly the source size and distribution pattern of a LED is totally different from a filament bulb so a relector and lens designed for a filament lamp will not give the correct light pattern with a LED. This is particuarly noticable when replacing halogen lamps. The seond issue is legality. This depends on the age of the vehicle. Certainly for any vehicle post 1986 a replacement lamp must be "E" marked, The road vehicle lighting regulation 14 (no LED filament lamp replacements are approved or "E" marked). Earlier than this and it's not so clear, but dazzling another road user is an offence. Lights designed with LEDs built in can be and are approved. One example is retrofit LED lamps to replace sealed bem headlights. You can get these with "E" marks for vehicles with sealed beam lights or conversions. An example is the Guardian SB1LED, but beware, there are many units out there which are not legal.

I'd forgotten about Oyltite. It does work, I've used it on a leak in the seam of a wing tank on a jet in the pouring rain before flying back home across most of europe! The best slosh selant out there is PRC PR-1005-L http://www.ppgaerospace.com/Products/Sealants/Specialty-Products/PR-1005-L-Buna-N-Slosh-Coating.aspx But it's not cheap. Robert G8RPI

I'd use alumnium filled epoxy putty. Devcon "F" 10611 is perfect but expensive https://www.cromwell.co.uk/shop/materials-and-maintenance/engineering-coating-and-repair-products/500gm-inchfinch-aluminium-putty/p/DEV7112030X There are cheaper ones out there. Robert G8RPI

Your loose half shaft spline might be a candidate for a metal spray repair rather than a new shaft. I have to keep remiding myself how massive all these parts are when there is noting for scale. Well done and I'm sure you will make the run.

Filling the tube with a soft low melting point metal is one method. The resulting rod maintains its shape but is harder to bend. "Woods Metal" (also known a Cerrobend) was common for this. It melts at 70 deg C and does not shrink on cooling so eaasy to use but as it had 10% Cadmium in the original mix it's now considered a health risk. Roses metal is a non Cadmium option. You could use lead or solder but they tend to shrink on cooling. not a problem if the pipe is long enough. A homemade option is 50% Bismuth 50% tin/lead solder.

The Xylonite link Le Prof provided http://www.decolish.com/Xylonite.html Says that Xylonite was the material used for WWII gas mask visors. From my memory of these, especially the infant ones, the material would be very usable, if not ideal, as a hood window. British Xylonite Co Ltd was founded in 1877 with expansion in 1887 and 1897 so timescale is correct. Note that it's highly flammable being made from nitrocellulose.

Polishing a surface reduces it's ability to dissipate Heat. Radiation is much better from a black surface than polished. This is why thermos flasks and space blankets are silvered and electronics heatsinks are black anodised. Roughness can also help with heat transfer to airflow. Paint would only reduce cooling if it was very thick. The radiator fins dont have to be black as despite the name most cooling is by conduction to the airflow. Polishing a radiator surround and header tank will reduce cooling slightly and was probably done for appearance. http://www.npl.co.uk/reference/faqs/what-is-emissivity-and-why-is-it-important-(faq-thermal) Great work on the J!

Hi, My first (other than introduction) post. I've followed this thread since finding it and the Dennis thread at christmas and reading both from the begining. Wonderful work! I can now contribute a little on the brass plate issue. As well as Press-n-peel (letraset) for etch resists. you can get special paper for laser printers that lets you print an image and then transfer the image to the copper or brass by ironing the back of it. This is great for any intricate work and repeats of the same plate. See ebay items 111679671618 and 181718392764 or search laser printer pcb resist transfer. Keep up the good work. Robert.