Estes Partizon PSII

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Jolly Logic chute release, or deployment computer in the payload with a line out to a cable cutter, are both perfect for this situation. That way you are still using motor deployment near apogee but simply restricting the drag until a lower altitude.

Never thought of that option. Thank you! I will do some research on this as a cable cutter/chute release would be new territory for me.
 
Oh yeah, the new Chute Release from Jolly Logic looks awesome. I haven't tried it yet, but it looks very promising.
 
The Pro Series rockets featured prominently in Chute Release testing. They have gobs of room in them, so you can basically fold your chute like normal, wrap Chute Release around it, and voila: delayed deployment.

If you're unfamiliar with Chute Release, you can read the testing thread on our news page here.
 
Go to my thread on a Partizon build to see some optional construction ideas. With the threaded rod from the nose cone to the payload bay bulkhead and an eyebolt there, I can go light and low with an F50 and motor ejection or sky high with an I200 and altimeter/cable cutter combo. And I'll never lose the nosecone!

I like using chute protector blankets which give the most room in the sustainer for long motors and they are a necessity for the cable cutter.

You can't go wrong with the Partizan - nice size, easy to build and right price lately!

https://www.rocketryforum.com/showt...-Partizon-build-challenge&highlight=vulcanite
 
I was finally able to get some more done on this build now that I have some free time again. Last night I beveled the edges of the fins. I marked a line 1/4" back from the edges as a reference for sanding. I started with 100 grit on a sanding block and then progressed to 220 grit. The fins are due for another round of sanding and then sealing. I also sanded down the casting lines on the nose cone and roughed up the entire surface for paint.

IMG_6935.jpg

IMG_6934.jpg

I sourced some hardware for the shock cord attachment at the baffle and nose cone. For the baffle connection, I am using a 1/4" eye bolt with a 1/4" spring link. My hope is the spring link will make it easier to remove the shock cord (if needed) since the body tube is only 2.5" in diameter. At the nose cone, I am using a 3/16" eye bolt and 3/16" quick link.

IMG_6938.jpg
 
I was finally able to get some more done on this build now that I have some free time again. Last night I beveled the edges of the fins. I marked a line 1/4" back from the edges as a reference for sanding. I started with 100 grit on a sanding block and then progressed to 220 grit. The fins are due for another round of sanding and then sealing. I also sanded down the casting lines on the nose cone and roughed up the entire surface for paint.

View attachment 282163

View attachment 282164

I sourced some hardware for the shock cord attachment at the baffle and nose cone. For the baffle connection, I am using a 1/4" eye bolt with a 1/4" spring link. My hope is the spring link will make it easier to remove the shock cord (if needed) since the body tube is only 2.5" in diameter. At the nose cone, I am using a 3/16" eye bolt and 3/16" quick link.

View attachment 282166

I've thought about those spring links for tight squeezes. Anyone else use them and to what effect?
 
I was able to work on this build some more the past couple of nights. Between my job and working on a remodel project at home, I haven't had a whole lot of time.

Last night I attached the fins with the help of a template I printed out online and glued to a piece of 1/4" foam insulation that I had on hand. Prior to that, I sanded the fins, applied a coat of spray polyurethane, sanded, applied a thin layer of lightweight spackle and then sanded to finish.

Partizon_Aft.jpg


Up next I plan to work on the internal and external fillets, install the rail buttons, aft centering ring and motor retainer.
 
Can't wait to see how it turns out. I cut about 5" off mine and added a forward payload bay and baffle. Payload bay carries an altimeter and Mobius camera. Super stable rocket. I use a Chute Release coupled with a drag chute for the descent. Works great. Next month I will fly it for my L1 certification
.IMG_1362.jpgIMG_1363.jpg
 
Last edited:
I've thought about those spring links for tight squeezes. Anyone else use them and to what effect?

I'd vote "No". There's a easier way and IMHO a safer way than that.

The carabiner will likely have some part of it that will wear on the kevlar. Also residues from the exhaust may damage the metals involved over time and you'd have no way of inspecting it.

My recommendation:
Tie a loop into your kevlar (I use a bowline), then push the loop through the eye/U bolt.
Pull the loop back up to just short of the top of it's parent body tube, and mark the other end of the kevlar.
Tie a loop on that end. Now you have a length of kevlar that is nearly (but not quite) twice the inside length of the parent body tube.
Tie a loop into your other shock cord material, and attach all three loops together with a quick link

When you want to inspect the kevlar, you can simply pull the loop around to look at the aft end, and if you need to replace it, tie a new length to the old and pull it through the eye/U bolt.


I also like U bolts over eye bolts, as they can't accidentally spin themselves loose on descent (though epoxy would likely prevent that from happening), and can't be pulled open without forces that would destroy the rocket so there's less of a chance of it being too weak.
 
Last edited:
I've thought about those spring links for tight squeezes. Anyone else use them and to what effect?

I agree with K'tesh: those spring links are not really suitable for the task.
I use some small climbing carabiners in one of my large 7.5 inch rockets. They are anodized aluminum alloy not unlike rocket motors, load rated, and definitely meant to be used with nylon slings. I inspect and clean them. I like that the gates lock; I wouldn't use them otherwise. But they are too big for small rockets.
 
I did a test fit of the baffle last night. Once the rail buttons are installed, I can permanently attach it and continue on with the 3rd section install.

Baffle_Test _Fit.jpg

Baffle.jpg

Baffle_Front.jpg
 
Nice! I like your offset plate design. Is your eye bolt machine thread with a nut under the top plate? A good coat of epoxy will help with the heat on the plates and tube wall. That is if you haven't already. I think the lower H powered rockets are the limit for the regular eye bolts myself. I use a good dose of JB Weld when I use a wood thread version.
IMG_1338.jpg
 
Last edited:
Nice! I like your offset plate design. Is your eye bolt machine thread with a nut under the top plate? A good coat of epoxy will help with the heat on the plates and tube wall. That is if you haven't already. I think the lower H powered rockets are the limit for eye bolts myself. I use a good dose of JB Weld when I use a wood thread version.
View attachment 291930

Thank you sir! The eye bolt I used is only attached to the top plate with a nut which is why I went with thicker plywood. A tightened the bolt down enough to bury it in the wood and then placed JB weld on the nut and top side. Hopefully it will resist loosening itself on decent.
 
The rail buttons arrived from Apogee. I used pliers to slightly bend the flanges on the weld-nuts to account for the curve of the body tube. Afterwards, I drilled the body tube and epoxied the weld-nuts into place.

IMG_9282.jpg

IMG_9284.jpg
 
The rail buttons arrived from Apogee. I used pliers to slightly bend the flanges on the weld-nuts to account for the curve of the body tube. Afterwards, I drilled the body tube and epoxied the weld-nuts into place.

View attachment 292510

View attachment 292511
Good choice on the rail buttons. I used the same ones when I saw how thin the tubing sidewall was. It is good to see progress on your build.
 
After some additional sanding on the aft centering ring, it was installed and allowed to dry in place. Once the aft centering ring was secure, the motor retainer was epoxied in place with JB Weld. The baffle was also installed after I tested the nose cone ejection with compressed air.


IMG_9574.jpg
 
After more delays due to work, I have made more progress on the build. I sourced some 3/32" wire cable to act as an extension for the shock cord mount. The cable was attached to the eye bolt on the baffle and the shock cord will be linked to the other end. Once the extension was installed, I attached the final body section.

IMG_0212.jpgIMG_0213.jpg


Up next.....finishing!!!
 
Back
Top