gas jet

[J. Tranter]

I am looking for info on making a gas jet so I can make a small burner for a boiler I am making.
Does any one know how to make one? I am more intristed in making one tan trying to buy one so any info will be helpfull.
Thank you in advance.
John Tranter

[bogstandard]

John,

Making the gas jet is easy, getting the hole into it is the problem.

I have had this problem on the back burner (excuse the pun) for about a year now, I want to make some very small jets for mini bunsen burners to power flame lickers and stirling engines.

I need to drill holes between 0.004" to 0.006". I have the drills, what I don't have is the means to turn them fast enough to prevent breakage. From my initial calculations, for the smaller one, the drill bit needs to turn at 96K RPM to make it stable and rigid enough, if I am very careful in designing the drill feed, I could most probably get away with 75K RPM. I think your holes could be a lot larger, maybe 0.015" to 0.025". I don't know the exact size of the required jets, but in the UK they are numbered (metric I think) and I used to use from 4 to 8 depending on the size of the burner required. I would assume they are 0.1mm (0.004") for each step, so a number 5 would be 0.5mm (0.020").

I have all the bits to make a super high speed drill, using a very small pneumatic die grinder as the power source, having the time to make it at the moment is the problem.

I have made many ceramic burners for model boat boilers, but I have always purchased the jets for those, so if I can help on that score I will.

I do have some copyrighted info on using jets out of disposable gas lighters, but I think they would be too small and not robust enough for what you require. Another way is to use the ruby jewels they use in watches, but again, I don't think they would stand up to what your needs are.

Plus you also want to make them yourself, and I admire that. There is nothing like producing everything for a project.

Maybe this vid can show you the way to go for your project.

http://uk.youtube.com/watch?v=q6-4oyIoku4


Speed is the secret for drilling really small holes.


John

[J. Tranter]

So if I'm reading right all I should need is one hole in the center of the jet?
Thank You
John Tranter

[HS93]

this will give you an idea of the shape of the comercial jets also the size of jet for burner  size

http://www.forest-classics.co.uk/gas_jets.htm


http://www.forest-classics.co.uk/ceramic_burners.htm

Peter

[J. Tranter]

Thank you for that link. That helped a lot.
John Tranter

[bogstandard]

John,

Just to add a little.

A bit of info on burner designs.

See C-o-C.

There are basically some standard bits to the burner designs.
The jet is mounted so that it can be moved fwds/bwds in the air inlet area. This allows the mixing and velocity of the gas to be set up to give optimum performance. You will need to play about with jet sizes to find the correct one.

In the ceramic design, you play around with the position of the upstand (I used 1/4" diam brass bar). The bar is there for the gas to impinge upon and distribute the gas to all areas of the burner. Without it you will find that on a longish burner you will get uneven burn across the surface.

On the poker type, play around with sizes and positions of slitting saw cuts. It all depends on how long you need the burner to be. Using a dremel and one of the very small saws that you can get for them is a good starting point. After you have got it burning correctly, use that as a pattern to make the finished article.

I have seen gas poker designs that use a very fine metal mesh wrapped around a tube that has holes in the top surface of the tube. I have never played about with them, but they do seem to work fairly well, more of a burn along the surface rather than a jet effect.

I hope that this has been of some use.

John

[Stilldrillin]

Very nice vid! 

I`ve done a lot of cnc peck drilling in my time, smallest dia 1/8".

He looked a little nonchalent with the pinvice. Two hands would have been more stable..... 

[sbwhart]

Wow I'd never had thought of drilling that small free hand very impresive 

Cheers

Stew

[J. Tranter]

Thank you Bogstandard the C-o-C makes perfect sense now. I am going to try the poker type burners.
Now one last question. Where can I get drill bits that small?
Thank you all again
John Tranter

[bogstandard]

Hi John,

I had a quick look at US sites and found these very expensive metric ones, they go from 0.3mm (0.012") upwards, and should give you the range you require. The Imperial 61 to 80 number sizes might do just as well, but a lot more expensive.

https://www.micro-tools.com/store/item_detail.aspx?ItemCode=82615MD

I would try the 0.3mm to 0.5mm range for starters. Start off small, then open out to the next size up, it is easy to take metal out of a hole, bit more difficult to put it back in. Of course these starting points depend on how big your burner is.

Drill most of the way thru the jet with a larger drill, then finish off the last bit with the smaller one.


Have fun

John

[Bernd]

The way he drilled that hole reminds me of a wood working seminar I went to. The guy drilled a hole down the center of a piece wood like that.

Another idea about drills. Didn't watch makers use a drill known as a spade drill that was used on bow drills for dilling holes for the gears shafts?

I've got a book from Lindsay about making small drills. I'll have to find it and check.

Bernd

[SPiN Racing]

Checked my place I buy stuff from.. Wholesale Tools

Size 61-80 wire drills. 4.95 USD
http://www.wttool.com/product-exec/product_id/22567/nm/Wire_Size_Micro_Jobber_Drill_Set_WT_Import_

[J. Tranter]

Thank you all for all your help. This is perfect.