"Rocketry Photography" build (LOC 3" HPR kit)

[ActingLikeAKid]

FINALLY getting around to starting this build properly. This is a kit that was being sold briefly last year and is very similar to the LOC IRIS, but with fiberglass fins and centering rings and a 54mm motor mount.
I'd love to get this build done in time for a 10/20 launch; we'll see how that goes. I'm pretty much throwing out the instructions that came with the kit; they recommend a "build the motormount and fins, cut the bottoms of the fins slots, then slide the whole thing in" approach and I'm going to do the more traditional "internal fillets really carefully" method.
As is, with a 54mm mount, it looks like it could handle more motor than I'd ever want to buy; I'm thinking that the first flight will probably be a high H or low I with altitude around 1500 feet.
I'm planning on building this single-deploy with a Chute Release, and hoping to build out an ebay over the winter to do dual-deploy.
Putting out my rough instructions now so I can tick them off as I go through them and update (I hope!) with pictures. Open to input on this one....

1. Sand all to-be-glued components (CRs, fins, motor mount. Even though mmt is cardboard, it's glossy)
2. Mark motor mount for CR location. This is critical because the kit uses a slimline boattail retainer, so motor mount distance from the bottom of the body is critical. Also mark MMT for fins, kevlar location, rail button location, and camera mount location.
3. Notch top CR for Kevlar.
4. Glue top CR with CA and Kevlar in place. Test-fit with fins, adjust as necessary.
5. Fabricate rail button backing blocks.
6. Epoxy top CR in place; glue Kevlar along motor mount (both sides) being sure not to cover fin lines. Press top rail button backing into place. Let dry.
7. Install camera mount backing block on mmt (opposite side from RB)
8. Put screws in rear CR for removal. Install mmt into body and let dry; remove rear CR.
9. Install fins; internal fillets.
10. Install rear CR and motor retainer.
11. External fillets
12. Drill rail button holes, camera hole, and vent hole.

I'm doing a second set of steps because the upper half of the rocket can kind of proceed separately.

1. Install eyebolt and PVC plug into coupler
2. Glue coupler into payload bay
3. Fabricate sled; install PVC coupler onto sled (more on this as the build progresses; it's gonna be cool)
4. Install 4 rivets to hold NC on (the sled is only for an EggFinder and maybe a non-deployment altimeter)
5. Drill air sampling hole(s) for altimeter

After all that, it should be a matter of "sand it, paint it, install a shock cord and parachute, and send it up".

 

[ActingLikeAKid]

Pic!

 

[ActingLikeAKid]

Edits!
So my "pvc plug" idea just wasn't going to work. Going to try something else for a sled.
Coming along nicely so far otherwise, about to make the backing blocks for RBs and cam mount.

 

[ActingLikeAKid]

Update!

Done:

1. Sand all to-be-glued components (CRs, fins, motor mount. Even though mmt is cardboard, it's glossy)
2. Mark motor mount for CR location. This is critical because the kit uses a slimline boattail retainer, so motor mount distance from the bottom of the body is critical. Also mark MMT for fins, kevlar location, rail button location, and camera mount location.
3. Notch top CR for Kevlar.
4. Glue top CR with CA and Kevlar in place. Test-fit with fins, adjust as necessary.
5. Fabricate rail button backing blocks.
6. Epoxy top CR in place; glue Kevlar along motor mount (both sides) being sure not to cover fin lines. Press top rail button backing into place. Let dry.
7. Install camera mount backing block on mmt (opposite side from RB)

To do on the bottom half:

1. Play around with some sort of bracing system for the fins. Test fit a couple of times.
   
2. Put screws in rear CR for removal. Install mmt into body and let dry; remove rear CR.
3. Install fins; internal fillets.
4. Install rear CR and motor retainer.
5. External fillets
6. Drill rail button holes, camera hole, and vent hole.
7. Install rail buttons and camera mount

Completely revamping the top-half plan.

1. Buy stuff to make this kit DD eventually:
   1. LOC payload/ebay
   2. 2x#8 screws to attach NC to upper
   3. Large main
   4. Harness

Assemble ebay
Assemble upper
Fill & sand (esp. NC)
paint

[once I've had a SD flight and I'm confident in the rocket]

1. 1. Charge wells
   2. shear bolts
   3. rotary switch
   4. altimeter
   5. wiring & batteries
   6. drogue chute
   7. second harness
   8. make ebay
2. Assemble

 

[ActingLikeAKid]

Another update! Focusing on the booster now. Mostly just made the list of tasks more detailed.

1. Find stick that I can use to push down on mmt.
   
2. Use retainer as alignment tool. Double-check the location of everything, then glue in mmt. Remove retainer.
   
3. Print 2 copies of fin alignment guide from payloadbay. Using foamcore, make 2 fin alignment jigs.
   
4. Install fins; internal fillets.
5. Install rear CR and motor retainer. Lots of JB Weld.
   
6. External fillets. Possibly tip-to-tip fiberglass?
   
7. Drill rail button screw pilot holes, camera mount hole, and vent hole.
8. Install rail buttons and camera mount

 

[ActingLikeAKid]

Update: Better than using the retainer as an alignment tool, I aligned the mmt to just the right depth, drilled the rail button holes, removed everything, glued it up, then let it dry with the rail button screws in.
Right before the glue-up, you can see the blocks for the rail buttons. I also put in a backer block for a mount for an 808 camera; that's the one at the other side of the top of the mmt.

IMG_3748

• ActingLikeAKid
• Apr 13, 2019

Built an alignment tool from PayloadBay and got my first dry fit. Looks sharp! More than a little concerned that the tool I built didn't line up. This either means the slots aren't cut right or (more likely) I was off by 1-2mm somewhere on a cut. Looks like I'll have to do Round 2 With Extra Caution.

IMG_3749

• ActingLikeAKid
• Apr 13, 2019

IMG_3750

• ActingLikeAKid
• Apr 13, 2019

Got my order in with LOC, going to initially use the ebay for my Eggfinder.

 

[ActingLikeAKid]

Update: The slots are not exactly at 90 degree gaps. Which means that the fin guide won't work as built - if Fin A is aligned, the slot for Fin B is close; the slot for Fin C is off, the slot for Fin D is even more off.
New plan: Use the fin guide, but make the slots for 3 of the fins extra large, and glue in one fin at a time. Tedious, but it should work.