Fill Adapter

The fill adapter for the tanks can be made from off the shelf components. The fill hose can be obtained from Holley which is one of the listed suppliers in the data pack. There are two types, and the only difference is the color on the fitting, blue or red. The red is supposed to […]

Preheater grain

The preheater grain is required for proper operation of the motor and encourages combustion of the fuel grain. The materials are still produced by Aerotech but you must know what to look for on the RCS website. It is made from a section of Blue Thunder propellant 1 inch long with a 3/8 hole bored […]

off the shelf components

Although the forward closure is no longer produced it is available through RCS. It is highly recommended that you also obtain the data pack as well. I was able to obtain all but two of the components using off the shelf hardware with only minimal changes. The custom components are of course the injector plate […]

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 […]

Injector Plates

Perhaps one of the most critical parts of the forward bulkhead assy has been made and is in the mail. Thanks to a highly skilled teacher from Oregon, he was able to make me six of each of the 98 and 54mm injector plates from my son’s Fusion 360 drawings and STL’s. The rest of […]

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 […]

And so it begins

Perhaps the most important pieces of the puzzle are the data pack and the forward closures. Currently, I only have one set of closures but a second set is planned for backups in case of any problems. Next to the forward closure, the injector plate and pin valves are the next critical components. The injector […]