I recently rehabilitated my JJ Lastelick 'Logans Run Deep Sleep Flame Gun' that I'd purchased from a dealer-friend of mine back in the early 90's. It's built almost to the original movie prop specs, since my friend had 'procured' one of the movie originals and had it duplicated assumabley by JJ.
The unit I own was in perfect working order back then, and the flame it produced was exactly how it appeared and sounded in the film, magnificent!
But like a dumb kid, I had removed the cotton wading to clean it one time and didn't immediately replace it. Some of the calcium carbide had blow into the valve and basically seized it. No more flame, no more awe at the bright light it would make, a sad day indeed. I stored it away, finished school, moved out west, and forgot about it. Then recently I bought the Logan's Run blu-ray and watched it with the wife. Afterwards, I decided to look for that gun and try to get it working again. When I found it in storage several weeks ago, I started working on it.
*That attached image is for reference and is not the JJ Lastelick version.
The following is for anyone who owns a non-working JJ Lastelick's DS flame gun. Don't give up, it might still be made functional again.
FYI: JJ built these by welding the barrel directly to the frame (to prevent acetylene leaks), which makes servicing the valve difficult. Also its my understanding that these valves can be rather fragile and are obsolete or not available anymore.
1) The 2.5v cyclone battery is built/formed directly into the handle and is not removable, to do so would destroy the guns handle requiring it to be rebuilt. I used a simple variable power supply as a charger, and set it to 3v per the original instructions from my dealer friend. Luckily it took a full charge and the glow plug burned that happy orange glow again. Amazing 20+ years and the battery still works!
2) Just as when I had stored it, no air could get through that valve. I decided to soak just the top portion of the barrel in a shallow tray filled with CLR for a couple of days. I made sure to only submerge the barrel enough to flood the barrel and valve and not touch the glow plug or handle. That freed up the valve a bit and allowed gas to pass through it again. Then I shot s decent amount of WD40 into the tank port of the barrel and actuated the trigger until the WD40 start dripped through the front of the barrel. I finished by blowing canned air through the barrel since it was of a reasonably low pressure and I didn't want to damage the valve.
3) I bought some craft felt and rolled it as a filter (as I had seen in another recent replica), instead of using the original cotton wading. I slide it into the felt chamber (middle of gun), then screwed on the rear acetylene tank.
+ For my first test firing, I loaded the chamber with 5 calcium carbide pebbles, water, connected the battery, and fired the gun. It produced a decent flame effect result. But it was not at the full intensity that I remembered it did when it was new or at that same high intensity of the movie. When it was new and fully charged, I could get a couple of really large good high intensity flames, and then several smaller short shots. Now it was at least firing with a dozen shorter smaller flames. Subsequent firings seemed to clear out the valve more and more.
4) I decided that the gaskets probably were allowing to much gas to leak out, so I went to the local hardware store and got a few plumbing #48 rubber gaskets to replace both the cap and tank joint gaskets.
5) Success! The new gaskets worked well (for a few times then leaked) and the next series of test firings produced that larger screen correct flame effect and sounded spot on! But the gaskets are not the correct ones as it seems that they can not handle the warm gas reaction in the tank.
Next steps;
A) I need to get a better set of gasket and test fire again.
B) Also the switch that turns on the glow plug isn't working reliably. It's activated with the applied pressure from the purlicue of my hand. I'll research a potential replacement with the same version or another variation.
C) And I'll update with new pictures from the test results.
