That's OK, but 'abkneifen' means to pinch or nip off, not pierce. Obviously a hypodermic needle's already pierced, and to do so again, for example by a side hole to admit air, wouldn't really be easy.

Could "abraded" mean to file the side wall of the needle to create an air inlet. It could also mean filing the point of the needle as hypodermics have slanted points.

Mick

I think I would leave the standard bunsen closed then use a Dremel to notch the side of the needle. Turn up a small sleeve that is a firm fit over the needle and just slide that up and down to adjust the flame.

I have some difficulty in seeing how an air inlet can be created.

In a bunsen burner, the jet is used to restrict the flow of gas and to create a jet of gas which sucks air into the airhole.

Without re-jetting the burner, the flow will be restricted by the needle, not the jet, Therefore the pressure lower down in the needle will be above atmospheric, and not below: therefore gas would escape via the 'airhole', rather than air coming in.

Maybe with a very small fast flame, it will burn efficiently without an airhole?

NB could be best to use a dispensing needle (not sharp and cut straight across the end), not a hypodermic needle, unless the taper of the needle end is beneficial in terms of mixing air into the gas – would abrading/reshaping the tip help?

Edited By Martin Whittle on 23/08/2017 08:48:04

I'd agree with that.

My own impression is that:

i) Google's algorithm looked for an existing translation first before trying to do it itself, and found one, and

ii) whoever wrote the original was guessing, and hadn't actually made the equipment.

Mind you, I ain't done it neither – but what I'd suggest is using the needle tube from an inkjet-cartridge refilling syringe (or suchlike) as the mixing/burner tube, with part of a fine hypodermic needle as the jet. Then make a sleeve with an airhole to fit over the burner tube. I think there'd be a fair bit of watchmaker-fine engineering to do to fit this lot together, with a number of different possible solutions, but in principle it's a miniaturised Bunsen.

A Google search for micro bunsen produces a few options, but most look a bit too big or otherwise iffy for a 2mm flame.

Edited By Mick B1 on 23/08/2017 09:38:42

You can get assorted hypodermic needles without a bevel cut and blunt ended needles too. Example of the former would be a spinal needle for the latter some form of tiny trochar/cannula or if larger then a sprule needle. Much more expensive as tend to be sold in units rather than boxes of 100 and less easily accessed for the hobbyist. Easiest place to pick up hypodrrmic needles.. either local vet (unless he thinks your a 'user' or just pop down to local agri feed/general supplies merchant who sells them in small numbers.

I'd experiment with a filed notch for air flow (or better a fine point highspeed bur) but it's going to weaken the walls of a very fine needle which might be best reinforced by sleeving with another which could then be used to adjust that airflow if counter-notched.

Edir… I see others posted similar principles. But lookign again at the original pic… back then hypodermic needles has steel hubs. You can still get them like that and that's what;s wedged into the rubber? tubing. Then one drills the airvent into the needle hub which it pretty solid

Edited By pgk pgk on 23/08/2017 09:42:55

Could always take the jewlers option and have a small hose off the side that you can blow through to intensify the flame. This would force the air in rather than hoping it will be drawn in.

Or for about £3 on e-bay you can buy the small "pen" size torches that have a flame about 2-3mm wide. Refil with lighter gas.

This was the type I was thinking of.

Messing around as a child I used hypo needles, large for bum injections, on a camping gaz stove. Very difficult to get a small enough gas flow with that to avoid blowing out the flame but it would burn with a yellow 'no air' type Bunsen flame. I thins Jason had the best idea with the jeweller's trick of a blowpipe. I suggest a good gas valve be made first.