Advice on building up Estes kits for MPR power + motor selection

I am planning to build up a couple of cheap Estes rockets up for F launches in the next couple weeks. One will be a Stormcaster, the other will be a Fat Boy. I have the two kits and the "E" sized mount for the Stormcaster. The BT80 engine mount for the Fat Boy should show up soon. I built my own 12V controller to launch the motors and should have a custom launch pad soon after a couple trips to Home Depot.

I am planning to build each kit with epoxy fillets, Kevlar shock cord sections, nylon chutes, and the Fat Boy will be modified with a bulkhead in the nose cone to allow more room in the body tube. My primary area of concern is the fin strength. I tried coating some fins with CA glue in the past but it did not dry smooth and once I sanded the fins flat, they did not gain much strength.

For motors, I am going to go with Aerotech F21s since they will slide right in to 24mm mounts. The F21s are availible to me, unlike a lot of other Aerotech engines.

On with the questions... First up, what is the easiest way to reinforce the fins to get good results? If I go with the CA route again, what type of CA glue are you all using? Would a 6 second delay F21 be OK in both rockets? I do not have RSim or anything to sim with...

I built a fatboy for f motors and the mods I made were to laminate card stock to the fins with gorilla glue and coated the crs with ca, I had to add some nose weight about two ounces. It flew great every time. That sucker rocked on a F-21. It wound up in a lake with a fence around it

With the 2 ounces of nose weight, did you ever feel like it needed more or less?

I did not think about reinforcing the centering rings, good tip

I've modded a Phoenix, Executioner, and Big Daddy for 24mm AP reloads. I used LOC 24mm motor tubes, coated the CR's with epoxy, built with epoxy, and on the Phoenix and Big Daddy, swapped the balsa for basswood. not too much heavier, but a heckuvalot stronger.

Loopy

Originally posted by grimlock3000
I am planning to build up a couple of cheap Estes rockets up for F launches in the next couple weeks. One will be a Stormcaster, the other will be a Fat Boy. (snip)

Click to expand...

If you are planning to fly a Stormcaster on an F21
my suggestion would be to take the picture
before you hit the ignition button.

If you are planning to fly a Stormcaster on an F21
my suggestion would be to take the picture
before you hit the ignition button.

Click to expand...

But the pictures of the Stormcaster stuck in a tree would look sssooo cool...

Anyone have RSim that can do F21 sims on the Stormcaster and a Fat Boy with 2oz of nose weight?

My 29mm FatBoy got: a 29mm LOC tube, a ply front ring, doubled-up stock rear ring, glassed the fins (waxpaper sandwich method), long nylon shock tether, cut off NC base and added nose weight to move the CG to stock location.

Don't forget that fins have to survive landing. A bigger chute can help but will also mean longer walks. I chose to beef it up a bit and go with a fairly small chute.

My Rsim is on EMRR. Don't believe the actual mass components as I did a final over-ride for mass and CG.

I have two Fat Boys that have seen some serious action.
First, is a 24mm Fat Boy. I cut the base of the nose off, put in two ounces of nose weight, epoxied a ply bulkhead over the nose weight, and used a kevlar shock cord mount. The fins are stock balsa coated with white glue, centering rings are stock, and the motor mount tube is the thicker Estes tubing. Empty weight is 5 ounces. It has flown on D12's up to the F21's. The F21-6 is perfect. I recover it with a Top Flight 12" chute.

Second Fat Boy, is a 29mm. LOC motor tube, 1/8" ply centering rings, stock balsa fins laminated with epoxy and printer paper, nose base cut off with a ply centering ring for the bulk head, motor tube extends into the nose for no wadding ejection, 3 ounces in the nose, nylon cord shock cord anchor, and a T-nut for motor retention. Empty weight is 11 ounces. It's made three beautiful flights so far, all on G35-7's. Recovered twice with a 14" nylon chute, and the last flight used a 7x70 nylon streamer.

I have the Stormcaster and I am planning to launch it this weekend on something bigger then a E-9. I will try to snap and picture and tell you how it goes. But, I am expecting an AWESOME flight because even the E-9's make the Stormcaster(which is one of my favorite estes) look awesome.