How would you fix this?...

[Stones]

Too much baffle blew the motor and engine hook from the rear of this one. (Story to come later in events.) I'm planning on drilling out the baffle and just going with dogbarf from here on out. Any ideas on motor retention or replacing the motor hook? It's a 1.6 in. BT.

 

[Darian Rachal]

Stones, Probably the easiest route would be to just put a 1/4" engine block around the end of each engine, each time you fly & just friction fit the engine with tape(the old fashion way) to secure it. The 1/4" block would give you a little something to grab hold to, to pull it out. Since you did away with the baffle, the friction fit should work.

Otherwise, you'll have to go to the trouble of drilling one or two holes in the base of the rocket & devising some little bracket, secured by screws, to hold the engines in.

 

[KermieD]

C'mon, c'mon....waiting for that launch report and our encounter with the county's finest!

 

[jflis]

I notice that the engine hook is situated between fins. Here's what I have done in the past, when i REALLY wanted that hook back in there...

Measure up to where the top of the engine hook entered the motor tube. Cut a small square of body tube out of the main body at this point (as small as you may need)

Pass the engine hook, from the bottom, through the hole in the bottom centering ring untill you can see the end through the hole you cut. Place the top of the engine hook in place and secure with epoxy (just the top inch or so).

Using cardstock or segments of old body tube material, glue a narrow lip of material, on the INSIDE of the body tube, all around the hole you cut. When dry, glue the piece of body tube, that you cut out, back into the hole. Sand and fill as needed.

somewhat involved, but it works.

 

[KermieD]

That's a great idea! Another one printed out for my notebook here.

Unfortunately for Stones, that might not work for him unless he wants to take it up the other side of the rocket. The clip took about a 1/2" long strip out of the MMT along with it.

 

[Stones]

Originally posted by KermieD
C'mon, c'mon....waiting for that launch report and our encounter with the county's finest!

Hehe...I'm on it Kerm. I'll post the pic of our new "friend" and you can do the right up on that.

 

[jflis]

Originally posted by KermieD
That's a great idea! Another one printed out for my notebook here.

Unfortunately for Stones, that might not work for him unless he wants to take it up the other side of the rocket. The clip took about a 1/2" long strip out of the MMT along with it.

This can still work...

Once you have the area exposed (and you may wish to cut a larger panel from the body to aid in work area), you can cut a short, narrow length of motor tube to place over the area of the motor tube that has been damaged. I've done this several times also.

It will raise that end of the hook by the wall thickness of the material, but that shouldn't be a problem...

Also, depending on other factors, you may even be able to rotate the position of the engine hook 15-20 degrees

 

[Stones]

Tnx for the input guys. I especially like jflis' idea as "friction" fitting has never appealed to me. I"ll giver 'er a shot and post the results. Tnx again!

 

[jflis]

PIX take some pix as you do it, it would be *wonderful* for folks to SEE this "operation" in action

 

[Stones]

Originally posted by jflis
PIX take some pix as you do it, it would be *wonderful* for folks to SEE this "operation" in action

I'm not much on detailed explanations but, here's what I did.
(See attachment)

1. Motor hooked ripped out. 1/4" by 1/2" hole in MMT.
2. Cut about 1" of the rear CR out to install a new hook I made from spring steel. It is epoxied in just the other side of the motor retainer ring. The hole in the MMT was also epoxied, which helped to fasten the motor hook.
3. A piece of cardstock was cut to fit the repair and epoxied.
4. Painted and ready to go.

Not the easiest route but, I didn't have to mess with the BT this way. Baffle was completely removed so the pressure in the MMT should be neutral now.

 

[jflis]

fantastic job! Great repair finish too!

 

[eugenefl]

Great job repairing the motor hook! Building a great looking bird is hard. Fixing a great looking bird from a crash or malfunction is even harder! Fantastic job.