K line bubbling Water Tower.

All the bubbling tubes on towers - Marx / K-Line / AF / Colber - are "picky." See if you can get the bulb to touch the tube without touching the base - it could melt it. Try a small bulb if you have one to concentrate the heat to the tube. Good luck.

I had some luck cutting  small piece of tin foil and laying the tower on top of it... Otherwise, you may want to hook the tower up to a separate transformer.

The problem with bubble tubes is heat transfer between the hot bulb and the bubble tube. An air gap between the bulb and the tube defeats heat transfer by conduction leaving only heat transfer by radiation.

Performance can be improved by adding a good heat conductor between the bulb and the tube that makes intimate contact with both.

Try this:

1. Make a sandwich of aluminum foil with several tight layers. Keep the surface area of the sandwich slightly larger than the base of the tube;

2. Insert the sandwich between the bulb and the tube and then force the tube against the bulb to assure intimate contact;

3. Wrap aluminum foil around the joint to make a reflector for heat transfer by radiation and convection.

There is a heat sink paste or compound that may improve heat transfer from bulb to the bottom of the bubbling tube.  I have used it to install additional heat sink to transistors.

Charlie

Good ideas!  If i have time, going to mess around with it this weekend.

I have the oil field and oil tower. These tubes are finicky. I tried the foil, conducting paste, etc. But no guarantee. The general winner is that volts x amps thing called watts. Consider a bulb rated 14  volts and 1/4 amp or 3.5 watts. The resistance is r=v/i or 56 ohms. If you go to 16 volts, you get 0.28 amps or 4.48 watts. Bottom line is the other stuff is icing on the cake, but give it increased volts and tolerate a few 25 cent bulbs burning out.

Another mystery, 15 -16 volts on a zw is better than 15 -16 volts on a z4000. 

Just sayin, my experience!

Take the tube out and shake it up after it's been on top of the bulb for about a minute. Mine will start bubbling immediately following that.

Roger

Try a 5 Watt #1893 bulb. Line the bottom of the tower with foil tape to help prevent melting (but watch out for it).

I have several of these from K line, Marx, Flyer and Colber, maybe 14 or 15 total.  It is one of my favorite accessories.  They all receive the same voltage off of the same buss wire.  How soon and how well they bubble determines if they stay in my collection permanent or have to move on to someone else.  Kind of like pre-season games or spring training. 

I learned many years ago to just try them out and pick the ones I liked.  At one time I had a brand new Kline and it was the slowest to bubble.  The Flyer and Marx units are usually the most reliable and consistent.  I got two like new boxed Colber units last York which I have not tried yet. 

I would recommend lining the bottom of the plastic base with thin aluminum or copper plate material.  This will help dissipate the heat from the bulb that does not transfer to the tube.  If you have to crank up the voltage it may prevent your base from warping.