Just thought I would mention a new source for pre-made nozzles at reasonable prices.

Gas Jet nozzles for cookers, heaters and model engines.
They come in multiple sizes and are made from brass.

Number 3 which has a 0.15mm dia bore
Number 5 which has a 0.2mm dia bore
Number 8 which has a 0.25mm dia bore
Number 12 which has a 0.3mm dia bore
Number 16 which has a 0.35mm dia bore



I have not tried them because I spent the money for small drill bits and already have a working extruder.

But I did some research and found them here and was surprised that they are not expensive, unlike from other model engine builders who want 4 times as much.

Hope this is useful to someone.

Edited 2 time(s). Last edit at 04/27/2011 10:14PM by Sublime.

Nice find. I have ordered some to try.

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[www.hydraraptor.blogspot.com]

What size thread are on these, and is that hole the same dia all the way through?

@Nophead
I'm not surprised it is you giving them a go first, thank you for all the testing you have done in the past and in the future.

@Cefiar
Good questions. On the model jet forums where I found the no. to mm sizing it was clear that most hardcore model jet engine builders made there own by drilling solid stock, so i would think they are straight bored. As for thread size, well I think we will have to wait for Nophead to tell us.

I've got one of these around somewhere. Had to re-jet my trailer's water heater for high altitude. Don't remember where I put the low-altitude jet though. That was over a year ago, and I don't remember if the hole went all the way through the same size or not. I suspect not, simply because it'd be easier to drill through a bigger hole on the back so the small drill bit doesn't have to go as deep.

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I'm building it with Baling Wire

Sorry I was thinking a tapered hole not just a counter bore. So yes they have a larger opening in the back.

My brother turned one of these over to me the other day when I was talking through my extruder promblems with him. Had a larger opening in the back, I haven't it with me at the moment but prob slightly larger than 3mm. Guessing the thread was 3/16" but none too sure. There are also larger ones that have an internal thread (ie tapped not died).

Anyway BBQ stores have quite a variety in stock apparently. Down in Aus we have BBQ's Galore but I guess whatever the US Big Box equivalent is would also stock.

The hole in the back appears to be about 2.5mm and goes to within about 1mm of the tip.

A bit of research suggests the thread is 1BA. I have ordered a set of taps.

Edited 1 time(s). Last edit at 05/03/2011 06:46PM by nophead.

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[www.hydraraptor.blogspot.com]

Yes the thread is definitely 1BA.

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[www.hydraraptor.blogspot.com]

nophead Wrote:
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> Yes the thread is definitely 1BA.

Good to know.
It has also allowed me to figure out that it is called a Type A Jet and there is a Type D jet that uses 1/8"BSP thread which would be much easier to tap for most people. [birminghamburner.co.uk]

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FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
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Did you realize the details of using Carburetor injectors and another on Calor gas tips goes way way back in this forum from years ago. I cant re find the calor gas one but its is mentioned in forum posts.

[forums.reprap.org] Carburetor injectors

The UP printer designers must have seen this old old forum post and applied it to their printer.

If you look at the Ultimaker extruder tip it is also looks to be based on a gas tip.

I have used several varietys of the gas tips running as my extruder head using 1.7mm ABS they work very well the pain is the 1BA thread. I'm not sure if European LPG tips have a metric thread instead of a 1BA thread. No16 is the ideal size I have been using No5 drilled out to 0.35mm as No5 seems easier to get than No16. The length of the small hole varies from 2mm to 1.5mm on the tips I have tried out.
There are various Ebay reprap sellers supplying tips like this.

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Bodge It [reprap.org]
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BIQ Sanguinololu SD LCD board	BIQ Stepcon	BIQ Opto Endstop
BIQ Heater Block PCB	BIQ Extruder Peek clamp replacement	BIQ Huxley Seedling
BIQ Sanguinololu mounting	BIQ standalone Sanguinololu or Ramps mounting	Print It Stick It Cut it

My rep strap: [repstrapbertha.blogspot.com]

Buy the bits from B&Q pipestrap [diyrepstrap.blogspot.com]
How to Build a Darwin without any Rep Rap Parts [repstrapdarwin.blogspot.com]
Web Site [www.takeaway3dtech.com]

I wrote a page with a gas nozzle variation as its what i am using too, please feel free to edit or change as you see fit.
[www.reprap.org]


Tip is flat but i could give it shape by fixing it in a low rpm boring machine and using tools as a file and a normal lathe cutting tool steel. Much like hobbing the wade bolt.

I guess that in general the thread is one level smaller than the standard for the given size, that is to lengthen its travel so gas would escape harder - sort of speaking. So threads are typically "less than standard" ones.

There is a difference between the nozzles for natural gas and LPG (butane and propane). I think the ones for natural gas have higher diameters (as it has lower density and power). The ones mentioned probably are for LPG, as for natural i found up to 0.5-0.8mm dia ones. These nozzles are available because once you turn your heating furnace or cooking machine from lpg to natural gas or vice-versa, one has to change the nozzles accordingly.

On the inside there is a cone shape that points to the nozzle hole. So on the outside it can be machined into a similar shape.

Made the heater block so a wrench could fix tight onto it (above resistors) and like so i can change the nozzles one by one without touching anything else. Can be done cold but its easier at 100C+ temps.

Havent had any issues with mines.

Edited 1 time(s). Last edit at 05/20/2011 06:05AM by NoobMan.

Where are you based Noobman?

Reading your Wiki page it looks like you are not in the UK where our gas jets have a 1BA thread.

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Bodge It [reprap.org]
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BIQ Sanguinololu SD LCD board	BIQ Stepcon	BIQ Opto Endstop
BIQ Heater Block PCB	BIQ Extruder Peek clamp replacement	BIQ Huxley Seedling
BIQ Sanguinololu mounting	BIQ standalone Sanguinololu or Ramps mounting	Print It Stick It Cut it

My rep strap: [repstrapbertha.blogspot.com]

Buy the bits from B&Q pipestrap [diyrepstrap.blogspot.com]
How to Build a Darwin without any Rep Rap Parts [repstrapdarwin.blogspot.com]
Web Site [www.takeaway3dtech.com]

I am from Romania - and i bet you didnt seen that coming