Assemble and Install the zipperless bulkhead

Locate the zipperless bulkhead BH2.

The ½” thick zipperless bulkhead is identified as part BH2. You will see two ¼” holes in the center and four 9/16” holes around it’s perimeter. The two ¼” holes are for the 3/16” U-Bolt. The four 9/16” holes are for ejection gas passage.

Install the U-Bolt into the center of the bulkhead. Use the included hardware. The flat retainer plate goes on the aft side of the bulkhead with two ¼”hex nuts. Keep the bottom ¼” nuts flush with the end threads of the U-Bolt. The U shaped portion goes through the forward side of BH-2 with a flat and a lock washer. The U-Bolt is your aft recovery hard point. Tighten the nuts securely.

Hint:A drop of fingernail polish on the threads will help prevent loosening. Similar to locktite thread locker.

Hold the wooden bulkhead by the U-Bolt and check for fit into the top of the tube coupler. This should be a tight fit. Adjust fit if needed with some light sanding around the bulkheads OD. Spread a thin even coat of adhesive around the inside top of the tube coupler and the OD of BH2. Slip the bulkhead in place with a twisting motion. Stop when it is flush with the top of the tube coupler. Remove any excess adhesive from under the bulkhead (inside the coupler), this area must be kept clean and free of excess adhesive.Remove any excess adhesive and set aside to cure.

Locate the stiffy insert.

Apply adhesive to the outside of the stiffy insert and the forward end, a few ribbons of Elmer’s carpenters glue is best. Slip the coupler insert into the tube coupler, twisting as you go, push in until it stops at the bottom of BH2. Twisting will help distribute the adhesive evenly. The stiffy coupler will protrude about ¼” out the back of the tube coupler, this is normal.

Remove all excess adhesive and set aside to cure.

Assemble the motor mount

PLEASE READ THIS

Even if you don’t read anything else.

Take your time with the motor mount. Become familiar with the parts and their names. Lay the parts out and double check the procedure. Dry fit all rings and sand OD if needed, then glue. The motor mount needs to slip into the airframe effortlessly. Use a wrap around to draw straight circles around the motor mount tube, this will help with ring alignment. The assembly is quite simple, but a mistake here would affect the entire build.

Think twice. Glue once.

Retainer:

If you are going to use the supplied retainer (recommended) follow centering guide #1.

Are you going to use a commercial retainer? If so you must follow centering ring guide #2.

Locate the 38mm X 17” motor mount tube, the proper centering ring guide, ½” CR-1, ¼” CR-2 and ½” CR-3.

CR1 & CR3 serve many purposes.

1. Provide an anchor point for the rail buttons.

2. Holds the kit’s retainer and anchors the motor mount.

3. Anchor the motor mount to the aft end of the Zipperless coupler

4. Provide a thrust ring, which stabilizes the motor mount. This ring will transfer the motors thrust to the airframe.

CR2 also serves a couple purposes.

1. Creates and seals the forward end of the foam chamber.

2. Provides fin support.

NOTE:

The fin tabs fit between CR2 and 3. Be sure to verify that your rings are properly spaced. There should be about 7 1/16” between them. Once again a dry fit is called for.

Use epoxy to glue the forward most ½” thick centering ring in place CR1. This is now the forward end of the motor mount. Use a Popsicle stick to add epoxy fillets to both sides of the centering ring between the motor mount tube and the ring only. Keep the outside edges clean and free of any adhesive.

Remove any excess adhesive and set aside to cure.

Now glue CR2 place. Be sure to add an epoxy fillet on the forward side only. Do not fillet the aft side. To do so would interfere with fin tab mounts.

Remove any excess adhesive and set aside to cure.

Locate ½” thick CR3

Glue the aft centering ring in place unless you plan on foaming the fin can. In this case you will glue it in place later, after foaming.

Do yourself a favor … foam the fin can as suggested. This will result in the strongest ship.

Remove any excess adhesive and set aside to cure.

Mark the outside of the coupler assembly.

The zipperless coupler assembly is 6 1/4” long, place a mark at 3 1/4” inches from the forward end downward on the side of the coupler assembly. BH2 is the forward end of the zipperless coupler, the open end is aft.

Apply a few ribbons of adhesive starting at your mark all the way down to the aft end of the zipperless coupler. A thin coat is all that is needed.

Slip the zipperless coupler assembly into the forward end of the aft (16” slotted) airframe. Twist as you go to evenly distribute the adhesive. Stop at your mark. You should have 3 ¼” of the Zipperless coupler showing. Remove any excess adhesive from the bottom of the zipperless coupler assembly. Failure to do so will affect motor mount fit.

Set aside to cure.

The motor mount will slip into the aft (slotted) end of the 16” aft airframe and stop when it hits the bottom (aft) end of the Zipperless coupling assembly. It would be a good idea to dry fit and see what is about to happen. The motor mount needs to slip inside the airframe effortlessly. Lightly sand the rings if required. Do not over sand.

Apply a ring of adhesive around the upper face (forward face) of CR1 about ¼” wide. There is no need to place adhesive on the outside edge of CR1 or 2. This procedure will secure the motor mount to the bottom (aft end) of the Zipperless coupler assembly. Later, after foaming the fin can, CR3 will also secure the mount from the rear.

Slip the motor mount all the way up until it stops. It will mate against the aft end of the zipperless coupler assembly. Once it has stopped twist the motor mount slightly. This will evenly distribute the adhesive.

This method will insure a solid fin can. The zipperless coupler becomes a stop and an anchor point for the forward end of the motor mount.

Set aside to cure.

NOTE:Now is a good time to bevel your fins. I like to bevel the leading edge only, then ease the other surfaces.

Needed:

1. Framing square.

2. QuickBurst Rocket Rack. If you don’t have one ... shame on you. Order one next time you visit my site.

3. Good level clutter free work table.

4. Newspaper.

5. Epoxy.

6. Popsicle sticks, for mixing.

7. Small mixing cups. I use the little plastic cups, similar to the ones you do Jello Shots in : ) Any small disposable cup will do.

8. Mix your epoxy in small amounts. No need in wasting any of it. Once the epoxy starts to heat up and set it is pretty much useless. I invert the squeeze bottles and count seconds off. Six seconds of Resin, then add six seconds of hardener. Stir well but don’t waste a lot of time. You need to be quick and accurate.

Place the fin can on your rack with one of the slots aligned straight up. Secure the fin can to your rack with a rubber band. This will keep it from turning. Dry fit the fin into the slot, make sure there are no obstructions. It should go in easily. If not, sand or trim as required. We want the slot facing up for a reason. This will allow gravity to help us out. The epoxy will be a little fluid at first. When you set the fin in place the epoxy will seep downward and create a nice little fillet for us. If you foam the fin can as suggested there is no need to add do internal fillets.

Apply a liberal amount of epoxy on the root edge of the fin, all along its ¼” width. Place a bit where the fin will set on the airframe forward and aft.

Do not get any on the aft end fin surface where CR3 will rest. If you do you will need to remove it ASAP, this will interfere with CR3 seating.

Set the fin in place, wiggle it a slight bit to spread the epoxy. Set the framing square's long surface on the table, perpendicular to the end of the fin can. Eyeball the fins position in relation to the upward straight edge of the framing square. This actually is quite easy to do and you will have become an expert by the time you reach the second fin. Move the fin side to side until you have reached proper (straight alignment). Once you have it aligned, hold it still a few minutes. As the epoxy hardens you will be able to make fine adjustments in your alignment. In a few minutes the epoxy will have hardened enough to hold the fin stable. Once the fin has become stationary, you can release your grip. Walk away for about 30 minutes. Repeat the directions above for the remaining fins.

Set aside to cure.

The foam can be quite messy. Once it gets on any surface and is allowed to cure it will be quite difficult to remove, only sandpaper or a Dremel grinding stone will remove it. Calculating the exact quantity to use is impossible. The best bet is to sneak up on the desired result.

Needed:

1. Small disposable plastic mixing cups, like the ones suggested for epoxy.

2. Popsicle sticks, for mixing and pouring.

3. Tissue paper for cleaning up.

4. Trash can.

5. Newspaper to protect the work surface.

6. Proper ventilation (read product label for suggestions).

7. Keep water away.

8. 3 CC syringes. No needles, just the body of the syringe. Mark them so you don’t mix them up. This would be ugly.

I am describing the US Composites foam here. Other brands may have a different mix ratio and cure time. Always use the ratio suggested by the foam manufacturer.

Hint:

Be ready to do this. Have everything ready to go. You will not have much time.

In one of the small mixing cups add the proper amount of foam components. I suggest 3 cc’s of part A and 3 cc’s of part B. When ready, fill the mix cup from the syringes. Use a Popsicle stick to mix the compounds, mix it well. It is mixed well when it is all one color. Holding the fin can straight up and pour the mix between two of the fins. Gently tap the top of the fin can on the floor to evenly distribute the liquid foam.

Once it has quit expanding, move to the next section, repeat the procedure outlined above for the remaining sections. Note the level of the foam in each of the three compartments. Adjust the volume of liquid foam accordingly and add foam until the fin can is full up to the bottom of the fin tabs.

Set aside to cure over night.

Now you are ready to install CR3. Remove any remaining foam that will interfere with CR3 installation. Dry fit until you have the required clearance.

Apply epoxy to the inside of the fin can where CR3 will sit, the outside of the motor mount tube, and the fin roots. Slip CR3 over the motor mount tube and seat securely.

Remove any excess adhesive and set aside to cure.

Pinning the nose cone. Epoxy doesn’t always adhere to plastic well. I have seen a few bulkheads come out and the end result is a lost nosecone. This optional step will see to it that this will not happen.

Mark the center of BH-1 around the outside of the nosecone shoulder. Mark three spots equally spaced along this line. Drill 1/8” holes at your marks about 1/4” deep. Insert three 1” long sections of 1/8” Dowell rod into the holes, use Elmer’s carpenters glue or epoxy as the adhesive. Either will work.

Set aside to cure.

Once the adhesive has cured use a small hobby saw or utility knife to cut the Dowel rod ends off flush with the outside of the plastic nosecone.

Done. Sand flat if needed. Chances are your nose cone will never come off.

Slip the 18” forward airframe over the nosecone. Measure the nose cones shoulder length, and mark it on the outside of the forward airframe. Divide it’s length by two. This is how far down the screws go. Secure the forward airframe to the nosecone with two pan head wood screws spaced at 90 degrees. Do not glue the nosecone on as you may need to access this area at some time in the future.

Note that BH-1 has a 9/16” hole drilled offset to one side. This hole is an access hole for adding nose weight. Some motors will require it. Modeling clay can be pushed through this hole, or use shotgun shot/epoxy slurry, this will place the added weight as far forward as possible, giving you the biggest bang for the buck.

Locate the two rail buttons.

Position the rail buttons between any two of the fins, in a straight line.

Locate the center of CR-3 and CR-1, mark as required. Drill 1/8” holes here and screw the rail buttons on. The centering rings will provide a great anchoring point.

Locate the retainer clip.

Place the supplied clip next to the motor mount tube and secure with woodscrew. It’s best to use a 38mm casing to accurately locate the clip. Washers are used as spacers to correctly adjust the clip’s length.

Locate the 2 Kevlar recovery harnesses, parachute, 9 X 9 Nomex pad, parachute retaining cord (1/4” Nylon loop), 500lb swivel and 3 quick links. You have two pre-sewn recovery harnesses. One is 3 feet long and the other is 9 feet long. The short one attaches to the U-Bolt on top of the zipperless coupler at BH-2, the long one attaches to the bottom of the nose cone with quicklinks.

Remove the two screws holding the forward airframe to the nosecone. Separate the two. Attach one end of the nine foot harness to the nosecone U-bolt using a quicklink. Drop the free end of the harness through the airframe. Re-secure the nosecone.

Take the three foot harness and attach it to the U-Bolt at the top of the Zipperless coupler with quicklink.Now connect the two harness ends, and the parachute retaining cord with the third quicklink.

Done.

Tie a simple knot in the chutes shroud lines about six inches up from the end. Note the black marks at the bottom of the parachute’s shroud lines, these mark the centers of the lines. Keep these marks aligned while tying your knot.

The swivel should be attached to your parachute retaining cord. The knot used here is called a “larks head”. Pass the parachute retaining cord’s swivel through the eye in the Nomex chute protector.

You will use the same knot to tie your chute to the free end of the swivel. Pass the free ends of the shroud lines through the swivel eyelet. Pull the end through the eyelet up to your shroud line knot. Open the loops in the shroud lines and pass the chutes canopy through the open loops. Pull taught.

NOTE:

When you prep the recovery system, make sure all of the chute and the parachute retaining cord is covered by the Nomex pad. An easy way to do this is to push one end of the quicklink through the nomex pad eyelet. Now everything is covered.

Done.