My 4" Madcow Patriot Build

[Doug Rocket]

I am working on my L2 build with a Madcow Patriot. First I decided to make my nosecone capable of having romovable weight.

I first added a bit of weight to the tip.

 

[Doug Rocket]

Then I JB welded an extra CR I had that fit snuggly right before the shoulder.

 

[Doug Rocket]

I also 3D printed a tailcone to scale.

 

[Doug Rocket]

I am attempted to sand the fins according to the scale drawings as well. It was very tedious but I am satisfied with the results. I even had a friend of mine put all 4 fins in a 3D scanner to determine differences between each fin.

 

[Doug Rocket]

Here are some 3D scans via screenshot, you can see that fin 3 is perfectly sanded so there is zero deviation in the various areas and the diamond shape can be very clearly seen.

 

[Doug Rocket]

Fin 2

 

[Doug Rocket]

I miss, typed...fin 3 was what all the other fins were measured against. I liked the way fin 3 looked compared to all others so that was what the others were measured against. The colors represent how far off each fin is from fin 3, with red being the worst. It was a while ago I did the scans so took me a bit to remember what I was actually looking at....

 

[Bruiser]

Your build is coming along nicely. Kudos to you for doing the boat tail and sanding the fins. Most people don't bother with either but they add so much to the model.

-Bob

 

[Doug Rocket]

Pictures I took from the US Space and Rocket center here in Huntsville...I took a lot more detailed pictures so when I get to putting on the finishing touches...eventually.

 

[crossfire]

Then I JB welded an extra CR I had that fit snuggly right before the shoulder.

Looks like it's got enough weight just from threaded Rods and nuts

 

[Hobie1dog]

nice detail work

 

[Doug Rocket]

Looks like it's got enough weight just from threaded Rods and nuts

Yes it actually does have enough weight with the rods and nuts for a J500 motor that I plan on using. Once I finalize the overall CG and CP I will post the margins I have with the lowest weight (rods/nuts only) on the nosecone

 

[Hobie1dog]

One of the great ladies in rocketry around here wants to do this rocket so keep the posts coming.

 

[Doug Rocket]

I am using the Patriot schematics I found on the NAR website and a 4 inch body tube is just about to 1/4 scale.

 

[Doug Rocket]

I also am making the conduit rails. Glued two .5x.5x 32in. balsa together. Then sanded one side down using some sand paper over the tube to get correct curvature to glue them on. Actual rails are 4in wide so these will also be to scale. I ordered the vinyl decals from StickerShock and the rail stickers are going to be a perfect fit.

 

[Doug Rocket]

 

[Doug Rocket]

Been working on putting my Eggtimer GPS tracking system together. I am using a heat gun soldering technique, it makes it so easy to put these together and its my first time using this heat gun technique.

 

[Doug Rocket]

Tiny diode to solder on bottom right of board. Will show how easy this is..

 

[Doug Rocket]

Took less than a minute to solder this one led part on with the heat gun. I added solder paste to leads on the board and then put the LED part on to be soldered, the paste holds it in place. Then the heat gun blows super hot air to solder it together. Just gotta be careful to not blow your piece off once the solder starts melting.

 

[Doug Rocket]

Its working!
View attachment 20221029_120400.mp4

 

[Doug Rocket]

Got my ebay sled all figured out..

 

[Doug Rocket]

Picture.

 

[Doug Rocket]

Putting together 3D case for Eggfinder. Using heat on brass inserts.

 

[KenECoyote]

Very impressive build so far!

 

[Doug Rocket]

A break in World Cup action..back to work on this project...my on-off switch arrived for my 3D case I printed from thingiverse. I got an extra one just in case.

 

[Doug Rocket]

All buttoned up and working..

 

[Doug Rocket]

Pvc Charge wells and terminals screwed and glued in place. The top/main chute is with two charge wells for main and a backup. I will be using motor ejection and a backup using charge well/ematch for drogue.

 

[Doug Rocket]

Conduits glued on, now need to sand and shape them.

 

[Ez2cDave]

Some additional data . . .

Dave F.

 

[Ez2cDave]

MORE . . .