I recently bought some new jets and jet needles for my Primus model 1094 lantern. Originally the lantern was 300CP. Now I have bought both a 250CP jet and a 350CP jet. I also bought three 250CP jet needles and three 350CP jet needles. Is it possible to tell the difference between the 250CP and the 350CP jet needles? I am not able to distinguish between them. See attached photos.
For me, it is very hard to tell unless it is stamped on the needle. Someone here I am sure can help you with this and perhaps I can learn something, too.
Simple enough. Just measure the needle Dia with a vernier caliper and the smaller one will be the 250cp. ::Neil::
As neil wrote is the best way but I also seem to see that the ones in the picture are marked with two stripes. Do you also have some with three stripes ?
Hi everyone, The jet needles in the picture all have two stripes. But two of them af 250CP and three are 350CP (or vice versa). So the stripes don't seem to help me. I hadn't imagined that a caliper would be accurate enough for this task. But excellent that it can do the job. I will buy one. I suppose that a standard one like the one in the attached picture is sufficient. Thanks for the help!
@Lars Høyrup Jensen I agree, a micrometer will be better. A vernier caliper is good to own in any case but a good micrometer will give you a better reading on smaller dimensions. They are little more expensive but is well worth it. Personally I believe that the two stripes on the needles are only marks from the manufacturing process. Michael
Hmm, they are a bit expensive, those micrometers. Around 50 euro as far as I can see. I think I will go for the vernier caliper and hope that it does the trick. If not, it is good to have in any case, as Michael points out. What happens if you install a 250CP jet needle in a 350 CP jet? And vice versa (if possible)? BR Lars
@Lars Høyrup Jensen The 250 needle will go through the hole in the 350 nipple/jet and clean as much it can but not completely. The 350 needle will most probably bend or get stuck in the hole of the 250 nipple/jet. I write nipple/jet because in some parts of the world it is nipple and in some jet. Sometimes jet means only the hole. Have you tried manually to see which needle goes into the holes? All needles will go through the holes in the 350 nipple/jet but only the 250 needle will go through the 250 nipple/jet. Michael
A modern digital caliper would be perfectly good enough for this. Pictured was an analogue one - properly a vernier which the digital ones are not. They are much cheaper than a micrometer.
@Lars Høyrup Jensen Biltema has one micrometer for 115SEK but I do not know where you have the closest store to where you live in Norway. It cost less than the vernier calipers that Biltema sell. Analogue - 149SEK Digital - 229SEK Precision of the micrometer: 0,01. Precision of the calipers: Analogue - 0,02. Digital - 0,03. Michael
There is the measuring error to consider when using a vernier calliper. The vernier calliper, on such a smaller diameter wire has the potential to be slightly at an angle, that is not measuring at 90deg to the wire being measured thereby measuring slightly more. The micrometer, because of the clamping between the spindle and it’s anvil, will be automatically measuring the true diameter of the wire. Just my experience speaking. Cheers Pete
I bought a vernier caliper. I was not able to measure any difference between the different needles. Then I tried putting the needles through the hole of the CP250 jet (good idea, Michael!). They all went through without problems. I am beginning to suspect that the needles are all the same size (and probably CP250). Not the biggest problem in the world. My lamp seems to work with the needles even though the jet I have installed is 350CP.
