BALLS 34

Lust 4 Thrust II Building on what we learned from the 54mm Aerotech hybrid revival project, my son and I will be working on the 98mm version with some changes to the original design. There is a 7-hole injector vs the original 4, and we may have a shower head style as well. In addition, […]

FLIGHT TANK

The flight tank is no longer supplied by Aerotech and Catalina Cylinders typically does not sell direct to consumer. Thankfully I stumbled across a direct replacement. They are available from racing CO2 shift systems. The best prices I have been able to find are from Jegs and Autometer. https://www.jegs.com/i/JEGS/555/60205/10002/-1 The above bottle requires that you […]

IT WORKED!!!

After test flying the Lust For Thrust on an Aerotech J570 on Saturday it was time to get the rocket up first thing Sunday morning. I was able to squeeze in 385 grams of N2O into the flight tank after chilling it overnight in the cooler and prefiling it with 50 grams of nitrous and […]

Balls Bound!

I had a few tasks to take care just before Balls. Unfortunately I did not get a chance to do a proper test firing due to the 50+ days of 100° and higher temps and the burn ban in my area. This post will update the final configuration for the tank connector and which grains […]

Casting the grain

The propellant grain is cast from a sorbitol mixture consisting of 80% sorbitol, 10% synthetic paraffin wax, 8% AL powder, and 2% red iron oxide as a burn rate catalyst. I was able to make a simple spreadsheet to help with the calculations. I have also included red copper oxide but that will be utilized […]

Ball valve Option

While awaiting the additional parts for the forward closure I was reviewing some of the Tripoli Facebook comments and one user mentioned a ball valve option. I looked into it and it is possible but the hardest part is acquiring the tank adapter, which I found. I was able to get a 5/8-18 UNF thread […]

Recert Complete

After a long absence, last flight 2006, I was able to renew my Tripoli membership, get my original number, and recertify back to level 2. Level 1 was accomplished in Nov with my scratch built Pershing 1A with 3d printed fins and nosecone on an Aerotech I218R. Level 2 was done Dec 3 with my […]

Pin valve Mods PT III

After drilling out the old pin valve I have cut some stainless 1/16 solid rod for soldering into the pin body. This will allow a higher flow rate by increasing the size of the orifice. After cutting down all that is left is some hand filing to get length close to the original, a new […]

pin valve modification part ii

In addition to reprofiliing the threads and enlarging the discharge port, other internal modifications need to be accomplished. The retaining plug for the pin needs to be drilled out to increase flow and the pin itself must be modified for a thinner stainless steel shaft. I drilled the retaining plug out to 0.190 which still […]

Pin Valve modifications

Unfortunately I have not been able to contact or obtain a pin valve from the original supplier listed in the data pack. The female threads for the forward closures for the pin valve assembly are 13/16 x 14, but interestingly enough the threads for a typical paint ball pin valve are 1/2 x 14 but […]