Severe problems encountered in mag hotwire mod

Like many of you guys here, I have been using both the potted WA bulb and Kiu's socket kit. I found two severe problem in the former (with the unmodded switch):

1. The spring loses its elasticity due to the enormous heat produced by the bulb. That means sometimes when the bulb is moved backward by the cammed reflector when the head is being continuously turned to adjust the focus, the bulb won't be able to come back to it's highest adjustable position as it did before as the spring is becoming much weaker.

2. The plastic tube, instead of the soldering points, melts. Here's what I mean (my mag 4C 1318/ overdriven by 3 18650):



I used this light for no more than 5 hours totally. The plastic tube melts and deforms to an extend that it prevents the bulb from being adjustable in it's position, and it prevents the cam of myreflector from going itside.

Has anyone encountered this problem before? Am I the only one having these types of problems with the unmodded switch assembly?

How long have you run it continuously? I've been using a potted bulb, with a standard switch assembly. I've always been concerned that something would melt and so I've never run it for more than about a minute. So far I haven't had any problems but the head and body still get very hot.

Interesting!

I have a Mag85 in 6D body running 4AH cells that I have used for almost two years and probably 2 dozen charges without any switch problems of any kind.

I did solder a copper braid from the switch tab to the cup below the lamp, but that is the only switch mod.

Bill

bwaites said:

Interesting!

I have a Mag85 in 6D body running 4AH cells that I have used for almost two years and probably 2 dozen charges without any switch problems of any kind.

I did solder a copper braid from the switch tab to the cup below the lamp, but that is the only switch mod.

Bill

Click to expand...

I am sure that is what has saved you, without this mod the spring is probably glowing just like an electric radiator. There is a fair bit of resistance in that spring.
Norm