www.pulse-jets.com

Very nice burn Ray;

A Q sized engine! Are they planning on lunching a VW BUG?

We do have built in hearing protection, but to what extent people can control it I don't know. Some people can control heart rate etc. The problem with the tensor tympani is that it is a very small muscle and doesn't have a long endurance time.
http://en.wikipedia.org/wiki/Tensor_tympani

Ray for the casings do they use the standard 6061 tubing stock or do they use the seamless tubing?

Glycerin is found in the pharmacy department for skin care. The Kroger brand is pretty cheap for what you get. Is there any way that you could use a brass or copper fitting from the hardware store as a nozzle? If not I will just cast some out of clay and try cementing them into the case like I did w...

Forget the wood glue. The case inhibitor was causing too many problems. Mainly because if it was going to fit, it would be too flimsy. I just tested another engine with great results. What I Did was make a casting sleeve out of paper and tape like on Jimmy Yawn's page. http://www.jamesyawn.com/skill...

I made an engine today. It had a really fast burn time, and eroded the nozzle worse than my previous engines I have made with paper. I will leave the steel washer out of the nozzle until I am sure the grain is bonding properly. The erosion is kind of a back up for over pressurizing. My next plan is ...

I won't have time to work on it today. I will keep you posted :)

Grain cracking is a concern, but I don't think that it is a problem the way I want to make my engines. The grain cracks when the propellant is pushed beyond its flexibility, right? In a core burner the web thickness is a lot less than in an end burner so an end burner should be less susceptible to b...

Consider C=C bonds stable unless you are going to reduce or oxidize them. Which usually involves a substrate and harsh conditions such as a catalyst, heat, and or a strong acid.

Does any body have any ideas on a way to bond rocket candy to the inside of PVC pipe? After practicing casting grains into case inhibitors I feel confident in my ability to go forward with an end burner configuration. I made some case inhibitors out of paper and wood good. I coated the inside of the...

Maybe this would be a good time to bring up the water injection thread to cool the engine and increase thrust. Should work good to put one on a boat. Silver solder has a pretty high melt temp and works good on copper. The copper will loose it temper after you heat it up and will remain a little soft...

Capillary action is not a good description. You are right that it is too large for that to happen. I am just trying to explain what I am seeing. The small diameter does have an effect on how they operate and it seems to be related to the surface tension. In my larger engines the hot water in the boi...

Mike that is true with the smaller putt putt engines. The problem is when you try to upscale them the water just runs out when steam is produced. The vacuum phase doesn't happen. So I am under the impression that it actually is partly due to capillary action. That is why I inverted my engine. This s...

Mike; Sorry for the delay I have been very busy with my new job. I think putt putt boats could be scaled up if you made an engine that replaces the two functions that surface tension provides in the smaller engines. What I have observed is 1, surface tension allows for capillary action to reload the...

I have managed to scale up putt putt engines quite considerably. The problem is that they are extremely inefficient. I think that this is caused by the lower surface area to volume ratio so the heat transfer doesn't work efficiently during the heat up and cool down cycle. Also the surface tension th...