AGM 33 PIKE standard 4" Madcow kit

[neond7]

Adding CA around the airframe below the ring to strengthen it up to help reduce damage on landings. Adding JB Weld to the MM prior to adding the retainer. JBWeld also for the retainer application.

I started my AGM 33 Pike build yesterday, so I'm following your build thread with interest. What I usually do to strengthen the tail end of rockets is to take a 1" section of body tube (available from mad cow rocketry) and cut a small slice out of it to reduce the outside diameter so it fits into the body tube and epoxy that into the inside of the rear and flush it up against the rear centering ring. Where I slice it to reduce diameter, I cut out a small round section and fit the backing of the rail button - I use the ones from Apogee Rockets that include the backing. Then I use a small amount of Bondo to hide the backing.

I attached some pictures of how I did this from a Phoenix build I'm also doing right now. You can just barely see the outline of the backing for the rail button. Its a bit lumpy right now, I'll sand it again and add more Bondo and sand it until its all smooth and you can't see where the rail button was. This method really does add a ton of strength to the rear.

 

[Buckeye]

They may work....but personally, I've never had a knot untie itself.

Agreed.

I think knots are "cleaner" than quicklinks all over the place. A bowline can be easily undone if needed, which is rare anyway.

 

[DizWolf]

Agreed.

I think knots are "cleaner" than quicklinks all over the place. A bowline can be easily undone if needed, which is rare anyway.

I usually torch the cords before I need to untie them

 

[crazyed]

Thanks for the input guys. I will post pic of what I have now eliminted link wise and the knots I have
I do feel better now how this set up. The links may very well have been the Weak links I don't want.

 

[Rocket86]

The Pike is a great rocket, one of my all-time favorites. You will love it and people will enjoy watching it fly. And don't lose it, like I did with my first.

 

[crazyed]

The Pike is a great rocket, one of my all-time favorites. You will love it and people will enjoy watching it fly. And don't lose it, like I did with my first.

What do you think about the I500 DMS and J270 for this kit.. Keeping the dry weight at 64 oz.?

 

[crazyed]

I started my AGM 33 Pike build yesterday, so I'm following your build thread with interest. What I usually do to strengthen the tail end of rockets is to take a 1" section of body tube (available from mad cow rocketry) and cut a small slice out of it to reduce the outside diameter so it fits into the body tube and epoxy that into the inside of the rear and flush it up against the rear centering ring. Where I slice it to reduce diameter, I cut out a small round section and fit the backing of the rail button - I use the ones from Apogee Rockets that include the backing. Then I use a small amount of Bondo to hide the backing.

I attached some pictures of how I did this from a Phoenix build I'm also doing right now. You can just barely see the outline of the backing for the rail button. Its a bit lumpy right now, I'll sand it again and add more Bondo and sand it until its all smooth and you can't see where the rail button was. This method really does add a ton of strength to the rear.View attachment 285591View attachment 285592View attachment 285593View attachment 285594

Nice...what motors are you planning?

 

[crazyed]

Time for the supplied bottom 1010 rail button. I drilled a small pilot hole thru the airframe and into the centering ring.packed a little JBWELD in there.( Sanded the airframe and button attach points first) screw it in. No crackling or splitting of the plywood ring( I like) a little more JB and its on to the top button. I haven't used rail buttons but 2 previous times. I've got those mounted flush and the buttons are secure and glued to the airframe. The instr actions here are to be sure the button is free to spin. It is mounted that way. Any other experience to offer?

 

[neond7]

Nice...what motors are you planning?

I usually start off with an I284w or a J350w. That J motor usually gives about 3,500 ft. or so depending on dry weight.

 

[crazyed]

I usually start off with an I284w or a J350w. That J motor usually gives about 3,500 ft. or so depending on dry weight.

In I 284 is a great one.. What do think about these button attachments. Suitable for an I and J? I don't have a lot of experience with buttons.they are installed as instructed and w/JB weld

 

[DizWolf]

What do think about these button attachments. Suitable for an I and J? I don't have a lot of experience with buttons.they are installed as instructed and w/JB weld

Those will be fine, take anything you can throw at them.

 

[neond7]

In I 284 is a great one.. What do think about these button attachments. Suitable for an I and J? I don't have a lot of experience with buttons.they are installed as instructed and w/JB weld

Those are the buttons I use - with the backing, they won't pull out. I have these on a 5.5" airframe and use K motors in it all the time. Should be good for any rocket less than 30 pounds.

 

[crazyed]

Thanks for those responses guys
Now on the retainer. AEROPACK 38mm. Sanded the tube and applied the JB weld liberally. Twisted on the retainer and there it is . It will look better after finishing.

 

[dixontj93060]

Thanks for those responses guys
Now on the retainer. AEROPACK 38mm. Sanded the tube and applied the JB weld liberally. Twisted on the retainer and there it is . It will look better after finishing.

Do you have a method to protect the motor mount upon landing? The way it is extended out there I expected another centering ring or thrust ring butted up against the end of the body tube.

 

[neond7]

Do you have a method to protect the motor mount upon landing? The way it is extended out there I expected another centering ring or thrust ring butted up against the end of the body tube.

That is true, with the motor tube/retainer sticking out below the airframe, it's going to take the brunt of the landing force.

I always try and recess it a hair into the body tube where it is protected. This also helps keep dirt out of the motor nozzle - people tend to set their rockets down upright when prepped and ready. I've seen people clearing dirt from their motors while they are trying to fish an igniter up into the motor on the pad.

 

[crazyed]

Neond7 has a great idea there. I was past that point in my build to take advantage of it

 

[crazyed]

My good friend Brett introduced me to these Aero Pack retainers. They are nice..and add a professional touch to the rocket not mention how well they work.

 

[Rocket86]

What do you think about the I500 DMS and J270 for this kit.. Keeping the dry weight at 64 oz.?

I made my Pike dual deploy and launch weight was a little over 6 pounds. I got about 2480 with the I284, and 2800+ with the J350 into a breeze.

 

[neond7]

I made my Pike dual deploy and launch weight was a little over 6 pounds. I got about 2480 with the I284, and 2800+ with the J350 into a breeze.

Quick question - did you add any nose weight to yours? I'll be adding a LOC avionics bay, and by switching it to dual deploy and moving the main parachute to the upper body tube, that should help move the CG forward.

I downloaded the OpenRocket file from Mad Cow and added the mods I'm making to the Pike I'm building now. It shows it right at 6 pounds with a J350W in it. The simulation has the apogee at 3138 ft. with 2.35 cal of stability and with zero nose weight added.

Too bad they didn't have a 54mm option with this kit. Even a CTI 38mm 6xl J600R motor tops out in simulation at 3857 ft. The field I fly on is big enough that 5K flights usually end up with on field landings.

After construction is complete I'll weight it again and see what the actual weight is - I tend to build a little heavy. So far, this is a very fun kit to build.

 

[Bat-mite]

I'm also in the camp of NOT using epoxy clay for fillets. I really like it for some applications (like bonding well nuts inside airframes for rail buttons). However, the epoxy clay I have used becomes very hard to the point of being brittle. My experience with epoxy fillets I s with Aeropoxy ES6209. It has some mild flexibility when fully cured. In the event of a hard landing a little flexibility may prevent a cracked fillet. Based on the positive feedback I have read regarding Rocketpoxy, I may give that a try after my current supply of Aeropoxy is gone.

Ditto. I did it once. Never again. Brittle, not to mention heavy! And hard to smooth. My fillets looked like the surface of the moon, and then later pulled away from the plastic fin can.

 

[crazyed]

After the appropriate jb weld cure time for the 1010 rail buttons and aeropack retainer, its time for the lower fins to get epoxied in place . Jeff mentioned in his build thread I think, he was having fun with his kit. I agree... Here are the pics of the knots I tied in place of two quick links. I've pulled and tugged to the point of a blood blister on my hand and these clamps are rock solid. The knots are solid to . lol

 

[crazyed]

I want to fly NOW!!! Its been way too long since I've had a large high power rocket. Here it is

 

[terryg]

Looks like it is ready for a J350W (one of my favorite motors).

 

[crazyed]

Yes..A J350W What goes thru my mind immediately is my chute size. I chose a 45 inch . Madcow recommended a 36 but I expect to add weight with DD. Do you think single deploy from 3400'/ 4.5lb rocket and 45" chute is acceptable at the SARA site? I know there is a formula for this but I don't know the site dimensions.

 

[crazyed]

If the waiver altitude is based on site dimension , could I figure 3250'x3250'

 

[Rocket86]

Quick question - did you add any nose weight to yours? I'll be adding a LOC avionics bay, and by switching it to dual deploy and moving the main parachute to the upper body tube, that should help move the CG forward.

No, no nose weight. Mine has the extra weight of redundant altimeters and probably too much paint. I also added a few ounces with some other recovery system parts and all were near the coupler/av bay but above the cg. Fully loaded with a 48" chute in the upper tube and J350 or J420 it had about 1.5 calibers. Fun to build and fly.

 

[terryg]

It sims out for me to under 3000 ft and our waiver is 6500 ft. The larger chute is probably the better choice since we land on hard desert ground rather then soft turf. It depends on the wind speed and direction at launch. If it is really strong go with a smaller engine or the smaller chute.

 

[crazyed]

There we go.. I can look forward to some awesome flights on J power before I deposit DD into the payload. Currently the CG is 2 calibers( 2x4) forward of the CP. without a motor. Addition of forward weight will be no problem when needed due to the large payload section. And at 65.1 oz dry and no paint.

 

[crazyed]

I built this rocket during this past week. Today I have a day off work. Oil change, windows come off the Jeep. And a pre summer wax job ( on the Jeep lol ). Then I can spend a little time on finish and figure out a way to do a quick/ in the field swap over of my 38mm av bay and missileworks altimiter from my mini DX3 for Dual Deployment into the Pike. 2 nuts and a removable rivet on the DX3 is all I have to do there. A way to secure the assembly in the Pikes 4" coupler is what I need to figure out. More to come.

 

[crazyed]

I started my AGM 33 Pike build yesterday, so I'm following your build thread with interest. What I usually do to strengthen the tail end of rockets is to take a 1" section of body tube (available from mad cow rocketry) and cut a small slice out of it to reduce the outside diameter so it fits into the body tube and epoxy that into the inside of the rear and flush it up against the rear centering ring. Where I slice it to reduce diameter, I cut out a small round section and fit the backing of the rail button - I use the ones from Apogee Rockets that include the backing. Then I use a small amount of Bondo to hide the backing.

I attached some pictures of how I did this from a Phoenix build I'm also doing right now. You can just barely see the outline of the backing for the rail button. Its a bit lumpy right now, I'll sand it again and add more Bondo and sand it until its all smooth and you can't see where the rail button was. This method really does add a ton of strength to the rear.View attachment 285591View attachment 285592View attachment 285593View attachment 285594

I found a small 5" piece of 3" loc airframe. I may try to fashion it to set inside the lower airframe per your nifty idea. Also back when I had a aerotech GFORCE I doused the coupler in CA for a smooth sturdy fit and easier deployment. I did it to this coupler as well and I like the result. The darker color is from the CA it also eliminates that "fuzziness" of the cardboard coupler. It will require a bit of sanding to get it to fit again and to get that smooth finish.