plan #17 Craft plane questions

[juki48]

has anybody built the pulse jet from the #17 blue print? the one called craft plane? I am in the process of building it and have questions about the drawing of the fuel metering assembly. any pics or advice would be great! by the way, this is my first post.

[Jonny69]

Hi Juki welcome on board! I have made it but never got it to run either on petrol, spirit, EZ Start or propane. I gather it's very tempermental due to its small size.

You might be better off building a larger engine as they are a bit more forgiving if this is your first one. The valve assembly etc isn't as hard to make as before as there are lots of 2-stroke reed valves available on eBay. Check out the thread 2-stroke Valves in the valved forum.

[juki48]

thanks for the reply. I think I'll give this one a shot. I have 1" and .5" tube in 321 stainless with a .020 wall which should be perfect. in the plans there is a drawing for an elaborate nose assembly. I'm looking for a little clarification of the drawing. if anybody has made this part a pic would do wonders.

[dynajetjerry]

Juki,

I have one of the engines you refer to but have never run it.

I think the complications with the fuel injector may be made worse by the usual inclusion of the removable starting-air nozzle assembly. You might be able to dispense with it and just blow air into the intake while raising the fuel tank enough to dribble fuel into the intake.

Might be a bit tricky but it works for several of my larger pulsejets.

Good luck.

Jerry Wiles

[juki48]

Thank you, after playing around with the drawing in pro E I think I have the more elaborate fuel metering drawing figured out. I'll have to post some pics when I have more built. do you have pics of your engine?

[dynajetjerry]

At the moment, the only picture I have also shows 30 of my pulsejets, including the Craftjet. When I have learned how to post attachments to my Emails, I will send many pictures.
Jerry

[juki48]

Well, I've started building my craft jet. seems to be going well. here's some pics. I used 321 SS tube .020" wall 1" and .5" I didn't weld them myself, a guy at work did it for me.

[larry cottrill]

juki -

I don't know anything about the Craft Jet, but what you've got so far looks like really nice work all around. I really hope you get her running!

L Cottrill

[juki48]

I've done some more on my craftjet. I made a threaded insert for the plug and had it welded in. in the pics it doesn't look like there is a flat serface for the copper gasket to seal against but there is. I milled it flat after it was welded. now I'll start the fuel inlet assembly. not too far away from firing her up! my dog Sprite really seems to like it!

[Rossco]

Beeeuuuudiful!

Keyboard wet from drool here on those welds!

Dogs learn by the way! Mine USED to like my jets too!
He especialy liked the "howling mode" and ran at the tail barking madly! That was till he got blasted. Fire ball burnt all his wiskers and eyebrows off! He learnt respect in a hurry, and it just seemed to take all the fun out of it for him.

Rossco

[Mark]

I bought a Craftjet on eBay once, I blew out the valve rather quickly and haven't the motivation to fix it. But I must say your little jet is coming along fine. If you haven't heard one run before, it is fairly loud, hearing protection should be worn.
Mark

[larry cottrill]

juki -

Yes, it looks really good!

That is a very small plug. What is the NGK number for it? Is the thread 1/4-32 like the little Champion ones I used to use (same thread as a US standard glow plug), or a fine metric thread?

Again, nice work. I think the little ones are really fun, but it can be frustrating getting them going. As Mark has said, the tiniest thing out of whack will make them non-sustaining.

L Cottrill

[Mark]

The ME-8 next to a Rimfire. The ME-8 has a tack welded side electrode, it looks funny, whereas the Rimfire is machined out, which is less likely to come off in your piston engine they say. Still, the ME-8 looks nicer with some lettering instead of a blank white stem to me. There's a little piece of protective plastic tubing on my ME-8, it's just the way it comes, perhaps to hold the washer on and keep the threads clean.
Mark

[juki48]

thanks for the complements! it is an ME-8. I called Advance Auto, my local auto parts store, and they can get them in one day for around $12. however I did have to give an explination of what one uses such a small plug for.

[Mark]

That's a much better price than where I buy my CM-6 plugs from. The CM-6 is very cheap from this site, ($2.25), but not the ME-8 at $20.33.
Mark
http://www.ngk.com/results_cross.asp?pid=me-8
http://www.ngk.com/more_info.asp?AAIA=&pid=3291