More free plans: 40 pound Chinese

[Barry]

Please,let we try to talk in ENGLISH!!!!So everybody can understand.

[Johansson]

For Johansson:
Less Dutch:

Put your propane bottle in hot water if it's cold outside.

Ha ha, thanks for the translation Fedde.

I know that I should keep quiet since I have been writing in Swedish here some times, but it is difficult for those who doesen´t understand the language what advice that have been given so they tend to avoid answering at all. The thread starter might miss some important info this way.

[Barry]

Ok now,I make the propane bottle warm and no differences.

I tried like Metiz says,to close one intake with the injector working & start the engine,when running deblock the closed intake,but it was harder to start & when I take away the stop,flames & finisch running.

Also GRIM make a movie,how he makes his injectors & offcourse I make them.Good news is that he running better than the other injectors,but NEVER with the both intakes open.
Now after 21kg of propane , I'am tired from all that testing.

Maybe somebody else have to make this pulse-jet & try to start it.

But I'am very happy that he runs with one intake & delivers very much power.

Here 2 foto's from the beautifull injector:





Barry

[metiz]

Hey Barry

keep tweaking the injector position. In the meantime, I'll start making this engine. I don't know when I'll be able to test though it's pretty cold outside. Might need to go for vapour+liquid run. Please try to make a video. Place your camera away from the engine as fas as possible and zoom in. It might keep running like that

[GRIM]

Hey Barry
Too bad you cant get it to run on both intakes, IMHO its a lack of fuel pressure ,
What size gas cylinder are you using ? for this size engine i would consider a 15kg cylinder the minimum on a warm day , on cool days (<15 deg c) i use a 45 kg cylinder ,
You mIght consider using two seperate cylinders one feeding each injector or connected together in paralell ,

I know its frustrating and costly , but a video of your one inlet runs would be very helpful in diagnosing potential problems ,

Joe

[Barry]

GRIM,I'am using 10,5 kg propane bottles.Today I heating it up with a big torch.I will make a movie outside,when it is not raining here.After all the snow & freezing it rains here.
But,I will make the 2 injectors to 1 point.I think with my system the right injector give more gas than the other one.It is always the right intake who gives problems.
I will work on that.

[metiz]

Started building my own M40. Yay!

Here are some pics of where I'm at - 3.5 hours in. The 2nd pic is a cone roling tool inspired by the one GRIM has is his backyard - decreased my roling time by 70 frickin' percent! AWESOME.

Fun fact: all the steel used here is scrap stainless bought at 2 euro/ kg just like all the other engines I build.
Total cost for the steel is about 8 euro

[Johansson]

Fun fact: all the steel used here is scrap stainless bought at 2 euro/ kg just like all the other engines I build.
Total cost for the steel is about 8 euro

Lucky bastard, I´ve spent about 80 euro on the stainless for my new engine so far and I haven´t made the augmentors yet...

[metiz]

Lucky bastard, I´ve spent about 80 euro on the stainless for my new engine so far and I haven´t made the augmentors yet...

Haha and it is not like it's shitty steel either: all industrial waste. Sometimes even wrapped with some plastic stuff that when pealed of reveals perfect shiney steel
Just go to the local scrap metal dealer for the best deals

Back on topic: just welded all the pieces. welding went like shit and only after I finished I saw that my welding tip was done for. Fantastic. Oh well, first time with proper gas, welds are still better then usual.

Still need to make holes in the choke cone and bend all the pieces back to round. They're all oval now. 6 hours in.

[Barry]

Hey Metiz , mine was build after 6h00".Cut the holes before make the cone is much easier.Sorry,I don't know the word in english,but I did it with a "decoupeerzaag" (whipping saw?)
Nice work you did already.

[metiz]

Hey Barry

decoupeerzaag is "Jigsaw" I think. I didn't know there were sawblades that work with thin sheet metal - got to check that out. I will need another 3 hours at least to finish this thing up I think. Actually, make that 4

how do you get the pieces from the steel - an angle grinder or some sort of tin snips?

[Johansson]

Cut the holes before make the cone is much easier.

I think I´ll disagree on this, I did just that on my first Thunderchine and it was almost impossble to form the cone after that.

On this engine I rolled and welded the cone first, made the intakes, painted out the holes with the finished intakes as templates and then cut the holes with my plasma cutter. Worked like a charm!

[Barry]

Yes,we have all plasma cutters......I'am not so rich Johanson,I have a machine,turning by hand with 3 rolls and that work for me because I have no better machines.
Just for hobby for me.

[metiz]

Yes,we have all plasma cutters......I'am not so rich Johanson,I have a machine,turning by hand with 3 rolls and that work for me because I have no better machines.
Just for hobby for me.

That's about the reply I was going for I'd kill for a plasma cutter and TIG welder. If you make holes with a plasma cutter, it wil toughen up the steel making it harder to bend. However, if you are not a rich Swede like yourself and have to make due with a saw or in my case, a freaking drill and a file (don't ask) It is easier to do when still flat.

[Johansson]

What, isn´t it a constitutional right to own a plasma cutter?

Have you tried using a nibbler for shop air? They are inexpensive and work fine on thinner sheet metal, should be of great help for these jobs.

(no matter what the method is I still think it is easier to get the cone perfectly round without any holes cut in the sheet)