Cracker burner

[Gordon]

I have been building a Cracker Loco and have it working on air but I am having a problem with the burner. I found where someone used a cheap pencil torch for the burner and I have tried that without much success. Too many adapters and parts to hook things together so it looks clunky. I appears that the jet gets plugged up as soon as I start taking things apart. The drawings call for a .2 mm jet and I have not been able to find anyplace to purchase something like that. Any leads on how to either build the burner or purchase a jet. Obviously I am not going to drill a .2 mm hole.

Gordon

 

[lowietje]

try a gas sigaret lichter.it has a smale jet
i used the gas filler cap to,to fill the gas container

 

[portlandron]

Check out "mister nozzles" they come in all sizes are made of stainless steel or brass.

http://www.mrdrip.com/Mist-Nozzle-BrassStainless-008-_p_320.html

 

[Gordon]

Thanks. I will look into that. I just found an orifice for a Bernz-O-Matic torch at the hardware store. I do not know how big the hole is but it looks like it may work.

 

[deverett]

Don't know where you are located, but have a look at eBay 200313425662 from a UK supplier.
Other size orifices available.

Dave
The Emerald Isle

 

[Gordon]

That is exactly what I need. Unfortunately I am in US and shipping is expensive and slow. I may end up trying to drill .2 MM (#92 drill) Never tried anything that small.

 

[sssfox]

Gordon, some random thoughts,

Since you are dealing with an orifice, you can drill a somewhat larger hole through most of the part and make the .2mm hole only the last 1/32" or so.

Also, it doesn't have to be the last part of the hole, you can turn the part around so the narrow section is at the beginning. That may keep it from clogging. A smaller hole in the part is a restriction in the gas flow, no matter where it occurs.

You could try making a "D" drill from a section of appropriately sized piano wire or a needle using a really fine grinding wheel.

Or, you could take a slightly larger hole, fill it with solder and push a hot needle into it to make a hole. You could mount the needle in a drill press to regulate the depth . It's only gas, it doesn't exert a lot of pressure.

By the way, I can't believe that there is a great difference in gas flow between a #80 and a #92 hole.

Steve Fox

 

[cfellows]

Further to what Steve said, all you need to do is drill a hole with the smallest bit you have then figure out how to make the end of the hole smaller. I read a DIY piece about reducing a gas jet diameter by swaging, but unfortunately, I don't remember where I read it or how they did it.

Chuck

 

[Jyman]

You can drill your self a round hole any size you want. then take a chunk of square and push it into the hole. so that only the remaining area of the round hole is equal to the area of the hole your looking for.


Sent from my iPhone using Model Engines

 

[Gordon]

The smallest bit I have is .5 MM which is over twice the area of the.2 MM called for. I can remember folks hitting a natural gas jet with a ball peen hammer to use them on LPG. This project was supposed to be simple. Somehow it got complicated. I have never run anything on butane before so I am in unknown territory. I don't think there is enough gas involved to blow the roof off.

 

[sssfox]

If you don't run into difficulties, you never learn anything.

Think of it as a cheap education.

 

[Gordon]

I am not sure that I want to learn so much every time. I certainly learn a lot or maybe I just goof up a lot. LOL

 

[sssfox]

Gordon,
Don't feel so bad.

I'm making a speed reducer for a 7x lathe and they have nonstandard timing pulleys. I'm on my fourth one and I think I finally have it right.


The first one stared out too big and I cut it down until it was too small.

The second one had a problem with my rotary table. I tried to mediate, but it still ended up with a couple of teeth that were out of place.

The third one somehow ended up with a center hole that was too large. It started out slightly too small, so I ran the boring bar through a couple of times without changing the cross slide setting to smooth everything up. I still don't know how that happened. Too much flex?

The fourth one is the correct size, but I haven't put it together yet.
I think I'm afraid to.

Steve Fox

 

[bb218]

150884345442 Item in Ebay for drill set that goes small enough. Or google for circuit board drills. Be sure an use an oil like Kroil for drilling the small hole and if you have a slide chuck that will allow you to use finger drilling pressure that will help. I used to drill Injector nozzles years ago before EDM became popular. Mike

 

[Gordon]

Thanks all. I think that I will buy the eBay set and make my own. Off to do some more investigation.

 

[Gordon]

Well I got the .008 drill bits yesterday so I am going to try drilling a jet. I think my chances are somewhere between 0 and -1. It looks like just breathing heavy would break the bit. I have a Grizzly CNC mill so that may be my best bet. I am thinking peck drill with a feed of maybe .005 at a time. The first problem is going to be starting the drill bit. Even spotting with a center drill leaves a flat which lets the bit walk when it hits the material. I drilled a .020 hole in the first one I made and using a center drill and then using a small center punch to form a sharp "V".