help with attempt at DIY butane stove

Hi Sean

While I am all in favour of MYOG, that canister connection … scares me.

I had a hose come off once and blow liquid fuel over my trousers. I managed to turn the safety valve off at the canister (my designs have a safety valve as well as a control valve) before the fireball did anything worse than melt a very big hole in my trousers. OK, it probably singed the hairs on my leg as well. Memorable.

SAFETY!

Cheers

Sean Rhoades wrote: > Not to worry about parting an Xtreme. I purchased those two parts from Coleman when I ordered a few jets from them, they were quite cheap.

Ah. Phew! I feel better now. :)

And yes there are canisters with Lindal valves that are not threaded. Coleman Powermax for one.

Currently I have no scales that weigh in grams or ounces, so I can’t say for sure what it weighs.

There’s always the post office!

HJ
Adventures in Stoving

Roger Caffin wrote: > Hi Sean

While I am all in favour of MYOG, that canister connection … scares me.

I had a hose come off once and blow liquid fuel over my trousers. I managed to turn the safety valve off at the canister (my designs have a safety valve as well as a control valve) before the fireball did anything worse than melt a very big hole in my trousers. OK, it probably singed the hairs on my leg as well. Memorable. [emphasis added]

lol. Understatement of the year!

Hopefully he’ll be in better shape when that spare gas tube he ordered arrives.

HJ
Adventures in Stoving

Well my gas tube arrived today, but I'm having trouble finding the correct size/thread fitting to attach it.

@Roger…Thanks for your concern. I tried not to test with my current setup much out of fear that your incident would happen to me. But that dang spare tube took so long to get here I couldn't resist trying it out. Thankfully all was well.

@Hiking Jim….Do you recall what size/thread you used to attach to your gas tube? It would help me out a ton if you did. :)

Hi Sean

Is this a 'screw thread' canister? If so, see
http://www.bushwalking.org.au/FAQ/FAQ_GasStoves.htm#Thread

Cheers

Sean,

The canister end is 7/16th UNEF (which is probably what Roger just referred you to). The other end I’m not sure. I had someone make a couple of adapters for me on a lathe. I can ask if you’re interested.

HJ
Adventures in Stoving

I appreciate you both for helping. It is indeed the other end of the hose (stove end) that I need an adapter for.

Jim,

It would be awesome if you could check about some adapters for me.

Hi, Sean,

Let me see what I can find out about those threads.

HJ
Adventures in Stoving

Jim,

Wanted to let you know I found out that the threads are 1BA. I also found out that those are quite rare threads in the US. At least seems that way to me. This is the thread for those gas jets used in model steam building, as well as Coleman stove jets. Problem is, I have yet to find any kind of adapter or at least something I can make an adapter from out there. It may come down to me soldering this thing together. Which is what I was trying to avoid. :(

Sean,

If you needed an adapter, what type of threads would you need to adapt it to?

Solder? Hmm. Could work, but sounds a little kludgey. Solder melts too easily. Brazing might be a better bet, but let’s talk threads first.

HJ
Adventures in Stoving

Jim,

For an adapter I would want to go from 1BA to 1/8" NPT.

Well not exactly solder. I've been reading up on something called Alumiweld. It's pretty much brazing aluminum to aluminum and also other metals from what I understand.

> 1 BA … This is the thread for those gas jets used in model steam building, as well as Coleman stove jets.

Ah, not sure you are right there. The 'standard' for jets is M4.5 x 0.5. This may be close to 1 BA (I haven't checked), but an exact match is better than an approximation. And there are quite a few sources for the metric taps even in USA (not to mention eBay!).

Yes, I have made many jets to fit in many stoves. The thread is easy, but the 0.25 mm hole is more fun.

Cheers

>> The 'standard' for jets is M4.5 x 0.5.

This is a common size but is not universal. Chinese stoves like the Gnat have a different thread for the jet.

I got that info from a live steam forum. Something about how Coleman bought out a company who was already using the 1ba. No clue how acruate that is. As for the taps, sure they're on ebay….shipping from outside the US. Thats why I was complaining. Ill have to check into the size you posted. Thanks.

The size I need for my gas tube would be around M6, but I've yet to get the threads right. The threads on my Coleman jets fit in there perfect.

For an adapter I would want to go from 1BA to 1/8″ NPT.

So, I’ve seen a lot of thread specs flying about. Are we for sure on 1BA to 1/8″ NPT?

HJ
Adventures in Stoving

Jim,

Right now I'm not entirely sure, I need to try and figure out if its really 1BA or the M4x.05.

Edit: Here's the link to the info about the thread size. Maybe Im reading it wrong altogether.

http://www.homemodelenginemachinist.com/index.php?PHPSESSID=5d484087c20705d9006ade59b7b54fd6&action=search2

The pitch on a standard M4 thread is 0.7, not 0.5.

Sean,

Before I go to my source, let’s get the thread issue settled. I wish I could help more, but this is definitely outside my area of expertise. Let me know what you come up with.

HJ
Adventures in Stoving

I'm a machinist. Trust me. :) The pitch on a standard M4 thread is 0.7.

What if you don't have "standard?" Thread gauges are inexpensive and will answer the question.

"What if you don't have "standard?" Thread gauges are inexpensive and will answer the question."

It's either M4 or it isn't. I only said 'standard' Metric thread, as you also get UF (ultra fine) Metric threads. That doesn't apply to M4.

I have used both of these dies. To be fair, .75 pitch is an old European size probably not used in over 60 years, but it does exist especially if one restores old stuff. Somehow I often get involved with things that are nearly impossible to find :)

> I'm a machinist. Trust me. :) The pitch on a standard M4 thread is 0.7.

Yes, the pitch on a standard Metric Coarse M4 thread is 0.7 mm. However, that is irrelevant.

The pitch on the STANDARD Metric Fine M4.5 thread is 0.5 mm. That is according to ISO 529 : 1975 and BS 949 : Pt 1 : 1976.
I repeat, I have machined many jets (from hex brass stock) for several brands of stoves, and that is what I use.

Cheers

Thanks Jim…

This is all definitely out of my league. I will do my best to figure out what thread I've got here and let you know.

"Yes, the pitch on a standard Metric Coarse M4 thread is 0.7 mm. However, that is irrelevant.

The pitch on the STANDARD Metric Fine M4.5 thread is 0.5 mm"

Make your mind up. So you are talking about M4.5 Fine now, not M4? ;)

Edit. I see it was Sean who used M4, not Roger. :)