
This is my first post here and the first time im building a valveless jet engine. i got the plans from this forum, i think from a post named "jims little 3LB thermojet". its a valveless thermojet engine that should give about 2-3 LBs of thrust ( as said in the plans ) and it seems good to start of with.
Im gonna start working on it this week and i'll keep uploading photos of my progress. Im gonna try my best to stick to the plans.
I bought stainless steel pipes today with internal diameters of 3", 1.25", 1". I got another two with internal diameters of about 1.2cm (~.47") and 1.5cm (~0.6")
But im not really happy with the 3" and 1.25" pipes because the metal is just too thick


ok now my first doubt is about the intake.. according to the plans the engine has two intakes of .5" diameter, so i was wondering if i should go for the 1.2cm tube or the 1.5cm tube.
Secondly, i was also wondering about the length of the combustion chamber. The plans require it to be 3" but would it be ok if i increased that to maybe half an inch more or reduce it half an inch or maybe a whole inch. would it be worth giving a shot?.
And lastly does the closed end of the chamber have to be slightly rounded? or will a flat surface suffice?
Anyways im really excited about this.. i've always wanted to build a jet engine since i was in the 8th. i used to cut out the bottom parts of cheese tins and make small cuts around it and twist the metal to resemble compressors of a turbo jet engine. but all i could do was look at it

Now when i read about valveless pulsejet engines and how it needs NO moving parts.. my heart skipped a beat. and no matter what im building one

and im uploading the plans that im using just so you would know what exactly im building
