TOPIC: Lighting Rapiers on the Flying Field

Hi Terry,
the current isn't a problem - it's only about 1.5 - 3 amps (I'm amazed that alkaline cells stand a chance of heating a wire to red heat). The pololu connectors are great for sticking into a pcb, but the simpler nylon 'chocblok' type are easier to mount in this case. My reasoning for the copper wire extensions was to provide a good electrical contact (fine wire into a screw terminal can be erratic) - and also to shift the red hot wire out away from the connector a little. I'll stick with the nylon connectors but, of course, anyone can try something different. Coming soon...

Sorry that it's taking me so long to wrap this up - am flying a bit one wing low at the moment. However, I did take the widget out yesterday to try it on the field. I found that my idea of using the silicone tubing to secure the element didn't work - although it was fine on the bench, the tubing split when the element was pushed into a Rapier. Not a big problem, really. Unfortunately, I was not able to ignite a Rapier - either with the widget, or the fuse wick. I tried 2 different motors, one of recent purchase, another of unknown age (I'd recently been given some). Is it normal to struggle to light these?

It can be. One thing that might help is to poke a very small 'instrument' screwdriver into the nozzle and into contact with the fuel charge. Twist it around to freshen the surface and maybe break off a crumb or two of the fuel.

One thing I must say, the latest batch of Tendera motors start very well on the supplied fuse and electrically.

there is indeed a certain 'knack' to lighting motors. The propellant needs a little 'boring out' with a 1mm watchmakers' screwdriver: insert said sharp implement and twist backwards and forwards with pressure. Do not go deeper than 1.5 mm. Retain the shards in the motor. Make sure the element is hot (glowing - they can be cooled in any breeze. Another trick I used with Rapiers, but have not (yet) found necessary with TSP motors is to bore out and add a pinch of finely ground match heads. The igniter does tend to eat batteries and there needs to be a good electrical connection for the element. So give the element a wiggle or two.

Thanks, both, for the tips. There's no problem with the electrical connection on my widget, and the filament was glowing bright red hot - but I just could not get the motor to ignite. I think that the scraping trick should make the difference.. and will be hoping to give it another go shortly. I had been thinking about using match heads, and am glad to read that I was on the right lines.

hi all, I trust that you will all be looking forward to resuming flying as the restrictions ease. Here in Wales, we've been allowed out a little and I was keen to get and try my ignitor with Rapiers and some of the new Tendera motors that Roger kindly sent to me.
Unfortunately, I have still not been able to get it to work.. Despite a wire glowing bright red, the motor isn't lighting. I sacrificed an old motor and ground out the propellant, sprinkled some into the exhaust port of a second motor, gently pressed it home - and although this ignition charge merrily burnt its way in, I am still yet to achieve a successful ignition. Perhaps it's the Welsh air...