Hello. I'm currently fixing the fuel gauge on my Radius lantern. It wasn't working, so I investigated and found that the wooden float had lost its buoyancy. So I replaced it with a cork I bought. It worked at first, but after about a day the cork absorbed oil and sank. I tried coating the surface of the cork with two-part epoxy resin, but it absorbed oil through small gaps and sank. Next, I attached a float made by cutting a PVC container, but when I used it under pressure, the air inside was crushed, perhaps because the adhesive at the connection of the float came off, and it sank. What kind of material should I use for the float? I'd appreciate any advice.
The original float was made of cork. I am surprised that cork would be affected by the kerosene, but maybe there are different types of cork.
@Nils Stephenson Thank you. The cork that came with it was so rough that you couldn't see the gaps, but the cork I put on was a container cap I bought at IKEA, so maybe that wasn't good. The water seeped in little by little.
I only know of two types of real cork. "Natural" cork or the "Grainy (Agglomerate) Cork" made of glueing small cork granules together under pressure. There are cork substutes "Synthetic Cork" that can look very similar but it is plastic. You could buy a very nice bottle of red wine and take it from there ? Or ask in an expensive European restaurant if you could have some old corks
@Fireexit1 Thank you for letting me know. I had no idea there were so many different types of cork. I'll try to get a cork that won't absorb oil as easily.
Choose natural cork with minimal defects or structural discontinuity. Avoid agglomerated cork. It should float on kerosene.
@Nils Stephenson @Fireexit1 @MYN I learned from everyone that there are different types of corks. Alcohol makes me feel sick, so I received a cork from someone who drinks. I don't know which cork is best, but I chose the dense cork that was originally attached to the lantern and installed it. Half a day has passed, and it is still floating. If it doesn't work, I'll try using the remaining cork. Thank you for letting me know.
Good news that something is working. So the ones that say “Nomacork” are synthetic, you can see the granular ones easily. That reduces the choice.
@Fireexit1 Thank you. I see. By the way, the cork I chose is the one circled in red. So far it's working well.
It is very difficult to tell from here. It may help to know - and forgive me if you know this already, "cork" is a natural material and is the bark of a tree. The cork oak only grows in Portugal and Spain.
@Fireexit1 I didn't know that. I thought cork was just wood chips compressed into a solid material. I don't know if the cork I decided to use this time is what you all call real cork, but I'll be happy as long as it works. I'm glad I've gained more correct information thanks to the different types of cork I got my hands on and your knowledge. I'd be happy if you would continue to teach me more. Thank you.
I think that one should work for quite a long while. Most solid plastic bodies would sink in the fuel you are using. Even some of the lowest density plastics like LDPE would barely float unless they are hollow or air-entrained. Polystyrene foam would float but it is structurally weak. PVC is quite dense and strong but not resistant to all solvents. HDPE plastic is resistant to most organic solvents and fuels. It can be used to make a hollow float. A solid piece of HDPE will still sink in kerosene or other fuels. If you use a piece of HDPE tube, you'd need to think of a way to seal the air inside. You cannot easily glue or bond the hdpe plastic. Most adhesives won't bond well to it...including cyanoacrylate superglues and epoxies. HDPE can only be securely bonded by heat-fusing. You can also use a metal float but it needs to be relatively large in volume so that its overall density is lower than that of the fuel.
@MYN Thank you. Before trying the cork, I also tried making a float by gluing together a PVC pipe and a board. The float worked well, but when the fuel tank was pressurized, the float could not withstand the pressure and collapsed, losing buoyancy. What was interesting was that when the tank pressure was released, the float inflated again and worked. The fuel tank, which expands and contracts when the fuel tank is pressurized, is unnecessary, so I threw it away. I tried to strengthen the float by making the PVC thicker, but this resulted in less air being taken in, and it failed because it did not obtain enough buoyancy. I eventually went back to cork.
Cork would be ideal for the lantern, since originality would not be compromised. Afterall, the right wine bottle cork would also be made using the best-selected corks. Unfortunately, these corks aren't commonly sold as separate items.
The two labelled Nomaco and TP look like the plastic cork replacement types. I expect kero would dissolve them with time. There could be others like them. The one labelled 20-23 looks like real cork. I had no idea about the source or production of corks until this thread. Thank you!
@MYN I agree. Not only is it functional, but cork looks great on old tools. @JonD I was surprised at how knowledgeable everyone was about cork. Everyone who gathers here knows everything and is very helpful. The cork I chose was the same type you chose. And it's still in use today. So you picked the right cork. Great choice!
Natural cork is a very interesting thing. See: Cork (material) - Wikipedia There is a plantation of cork trees planted in Canberra, Australia’s capital, one hundred years ago: Forest 1 - Cork Oak - National Arboretum Cheers Tony
As I typed it did occur to me that it must be possible to grow it in other countries. Given that it is sought after enough to justify making plastic stoppers. But Australia (understandably) has some pretty strict rules about importing flora and fauna. I guess yours happened before those rules kicked in. I am suprised that it has not been exploited more in Oz, but given the long time to get a return on the investment I can understand why maybe.
