comp3 build (l2)

right I'm supposed to document those areas that would be hidden on the finished rocket...step one nose cone prep . after removing the 'flange' that made it look like a squid(thought fg was supposed to be easy), I slathered on the spot putty, waited till dry and sanded nose with 220grit, this after sanding the shoulder into some resemblance of round. all for now,
Rex

first question; about parts. I was looking at the assorted rings, and bulkheads, and noticed a difference between received parts and the parts listed on the website. instead of 4 separate parts for the av bay, I got a pair of lids and a coupler bulkhead. do I epoxy the coupler bulkhead into the nose to provide an anchor point for the shock cord? thanks,
Rex

It came with a molded nose cone? That seems strange.

Filament wound is an option on kit if my memory is correct.

I would have thought that would be standard by now. Anyway, yeah, that's one way to do it - unless you want to use that space in the nose for something. You can embed the end of a threaded rod into the tip, extending it to the rear, and use the bulkhead as a "cover" of sorts - then the space in the cone can be utilized, most often for tracking.

Rex who did you buy the kit from?

molded G10 nose cone, the mold looks like it could use a bit of freshening up. got the kit from the Wildman. the tubes are G10 as well, bit of a step back compared to those nice G12 tubes.

guess I get to sand the inside of the nose too, lovely. thanks for the info.
Rex

Rex R said:

guess I get to sand the inside of the nose too, lovely. thanks for the info.
Rex

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Maybe not, depends on what you intend to do - the rough interior of molded cones is great to epoxy to.

got the bulkplate installed in the nose early this morning, later I drilled holes for shear pins(tapped for 2-56 in the airframe)...then had to drill out the remains of a 2-56 nylon screw. got it drilled out w/o damaging the threads, decided maybe I shouldn't press my luck further and stopped work for the night.
Rex

got a good start on the motor mount/shock cord anchor. 1st two rings are epoxied into position.
Rex

Rex R said:

got the bulkplate installed in the nose early this morning, later I drilled holes for shear pins(tapped for 2-56 in the airframe)...then had to drill out the remains of a 2-56 nylon screw. got it drilled out w/o damaging the threads, decided maybe I shouldn't press my luck further and stopped work for the night.
Rex

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Rex- not sure if you do this or not but after I drill and tap airframe and coupler in assembly, I take the coupler and open up the hole a few thousandths, just enough to remove threads. Makes for a much easier assembly in the field, especially when laundry and shock cord is in place.

Looks good. Looking forward to seeing it fly this year.

Rex R said:

got a good start on the motor mount/shock cord anchor. 1st two rings are epoxied into position.
Rex

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Your epoxy job looks much cleaner than mine. I have a tendency to be a bit sloppy on the insides motor area. Look forward to seeing what you get done next.

Rex R said:

got a good start on the motor mount/shock cord anchor. 1st two rings are epoxied into position.
Rex

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that looks like a pretty short bridle? It is going to limit the size of motors you can put in there. Also, it will be impossible to reach if you ever have to attach or remove a shock cord. Correct me if I'm not seeing this right?

Rrwjr said:

Rex- not sure if you do this or not but after I drill and tap airframe and coupler in assembly, I take the coupler and open up the hole a few thousandths, just enough to remove threads. Makes for a much easier assembly in the field, especially when laundry and shock cord is in place.

Looks good. Looking forward to seeing it fly this year.

Click to expand...

As well as doing this, I've found another way to make this easier. Rather than having to screw them in, drilling the air frame holes with a 5/64" drill allows you to just push them in, with about .003" interference to hold them tight.

chadrog said:

As well as doing this, I've found another way to make this easier. Rather than having to screw them in, drilling the air frame holes with a 5/64" drill allows you to just push them in, with about .003" interference to hold them tight.

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I might try your method Chad on my next rocket. Simpler and effective. Thanks for letting me steal your tip to Rex😄.

yep looks like I've limited myself to nothing bigger than a 'wimpy' K1100 , darn. well guess the only thing to do is get a bigger rocket next time. so what do you all think, pin the av-bay to the booster section? also have a reasonable start on my av-bay lids.
Rex

I see no reason that your harness couldn't lie between the case and the tube, if you wanted to go longer.

I think I see a reason for not going bigger(at the Bong), I seem to recall that our waiver is 10k msl...a K1100 predicted alt is within spitting distance of 9k agl...wouldn't want to bust the waiver .
Rex

chadrog said:

I see no reason that your harness couldn't lie between the case and the tube, if you wanted to go longer.

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The other thought was serviceability. There is no way to reach the shock cord (unless the bridle will slip out the back)

Either way, different strokes as they say. Back to the build, I'll shut up and go back to my Punisher build.

GRIFFIN said:

The other thought was serviceability. There is no way to reach the shock cord (unless the bridle will slip out the back)

Either way, different strokes as they say. Back to the build, I'll shut up and go back to my Punisher build.

Click to expand...

I hear ya', but what's done is done. If it only gets flown at Bong, He's solid.

GRIFFIN said:

that looks like a pretty short bridle? It is going to limit the size of motors you can put in there. Also, it will be impossible to reach if you ever have to attach or remove a shock cord. Correct me if I'm not seeing this right?

Click to expand...

I believe that the Comp 3 booster is 44 inches. I might be missing something, but that is pretty long. The bridle should be fine.

got back to work on it. did some sanding, and trued up the root edges of the fins...so nice not having to hand sand FG . ordered some PML rail guides in lieu of rail buttons, I'm thinking that I will want to install those before the fins, otherwise about ready to install the motor mount.
Rex

got the motor mount, rail guides, and fins installed. also got the internal filets done.
Rex

Looking good Rex!

Thank you. got the aft ring in place. next up the retainer and external filets...then I will have run out of excuses for not finishing the av-bay .
Rex

mmmm. K1100T will make a nice ride.

unlike my Lv1* I am not locking myself to any particular motor until I have it built .
*bought an H123 for my patriot...it worked and I got my Lv1 but, an H242 would have been a far better choice.
Rex

exterior filets still need a bit of cleanup but otherwise done. installed the retainer...my goodness that was a tight fit, almost didn't need epoxy . but yes I used jb weld, a small hammer, and a Delrin rod to 'tap' the retainer into place. Probably safe to say that the retainer is there to stay(touch wood).
Rex

Looking very good Rex. Sometimes if the MMT is a little big for the retainer I just run the Dremal with sanding barrel around MMT a few times so retainer will slide on a little better. See you at the Bong. Are you planning on a Eat cheese flight or MWP?