No-silbrazing downsizing of worn jet

Hi, John, I have found that the Op.111b runs best with a larger aperture than that used on the Op.111:

https://classiccampstoves.com/posts/87369

Best Regards,
Kerophile.

 

I'm grateful on two counts George, your observation about fuelling on an Optimus 111B and that excellent thread from a while back!

Of course you're right, a 111B goes like a rocket and with perfect fuel/air combustion mixture on that oversized-insert mangled jet





John

 

The pressed-in insert technique is proving itself to be repeatable and effective, most recently in this Primus No.4 fettle

This abrasive tip in a Dremel has proved useful ...




... removing the stub of insert after pressing it in




... and creating a 'dimple' to guide the pricker wire into the jet orifice when using it to clear a blockage




It's more apparent seen under a microscope









Creates perfect combustion



John

 

Nice to see this is working out so well.
I'll be interested to see where this all goes as far as technique
and the applications.

 

Here's another application Doug

Coleman Apex fuel pump inlet tube joint

John

 

Revisited 3 1/2 years later .. and amazed.

 

Good job

 

Interesting and resourceful. If you know any type 1 diabetics who use an insulin pump, you might be able to source some 26g needles used once to fill the pump. Usually one used every 3 days.

 

@IvanN, if you have a pet then your local vet should be a good source as well.

 

Excellent post thankyou!

 

Yes an excellent modification. It would probably be expensive for the manufacturer, but it's a pity that lipstick burners weren't sold with a similar modification.

 

Hello . I beg your pardon, I'm a beginner, I repair stoves. When repairing the nozzle hole, I drill the hole with a medical needle, then stuff graphite into the needle and solder with P14 carbide solder and a gas burner.

 

I ask for help from experts ... what is the diameter and thread pitch of the nozzle on R9, 99, 111? What is the diameter and pitch of the thread on the head? Thanks and sorry again

 

Very nice work @presscall , clean flames back like new :-)

 

I have a question, I have some needles that I saved for this purpose.( Read this post a few yrs ago) but when I looked at them today they are 20g. The package says 9mmx25mm does this mean I can still use them but need a bigger drill?

 

Incredible work.

 

@Duck

A 26g is quite a small diameter needle (in the scheme of needles) while a 20g is moderately sized. In intended use, a 20g would be considered (just) able to deliver blood, a 26g is much too small for that.

Check the tables for precise size, but I definitely would not consider those sizes interchangeable.

 

According to the table nope I wouldn't use it. It's the .9mmx .25 mm on the package that is confusing me. I'll just see if I can buy the 26g somewhere.

 

Is it possible that a less laborious procedure could accomplish the same? I say this not to be critical, but this is similar to what carburetor enthusiasts do for AFR tuning.

By way of background, the carburetor jets are offered in dozens of incrementally different sizes, and accurate engine tuning is very much a cut and try method, the jets run only maybe $10 the pair, but this can needlessly start to add up after a while.

Anyway, to get to the heart of the matter what they do, is solder a large jet closed, and then drill it out to the size necessary as required with numbered small gauge pin vise drill bits.

I should think drilling out a soldered jet with the correct orifice size will work fine for a stove in particular, though I haven't tried it. A high temperature silver bearing solder or something similar would have to be used.

 

@Fettler Provided a precision drilling rig is available micro-drilling is perfectly possible. Otherwise, it’s a sure way to break a lot of drills with few successes. Besides, the hypodermic needle insert procedure took a lot longer to describe than do.