Quasar

The PML Quasar is my second PML kit.  My first was a Tempest.  The Quasar comes complete with everything that you need including a KwikSwitch 2000 motor mount, a heavy duty nylon parachute, G10 fins, and a payload section.  I decided on this kit because of its looks and its performance.  I am building mine to take a J135-simulations say that it will go 7282 feet!  Anyway, on to the story.

I purchased the kit in the summertime after an orthodontist appointment, at HobbyTown USA in Brea.  Upon getting into the car, I immediately tore open the bag and looked at the instructions.  As usual, the PML instructions were minimal but enough.  See what mistakes I made on this rocket and how not to repeat them.

Flight Log

Flight #

Motor

Electronics

Performance

Comments

Flight Details

Design and Construction

Construction

First thing together was the KS2K motor mount.  This motor mount is interesting in that it allows you to switch motor mounts from 54-38 and 54-29mm in a matter of seconds, simply by  screwing in the proper adapter.  This went together easy with West Systems epoxy, although the thin epoxy (I used it unthickened for maximum strength) gave me a little trouble with the alignment of the tube in the urethane screw unit.  I ended up taking two long pieces of duct tape and taping them across the top of the tube to hold it straight.  I then laid the whole unit on the floor and taped everything to the floor, using equal tension on each of the pieces of tape.  This worked well for me.

While the mother tube was curing, I beveled the fins with a file.  I love G10 for beveling purposes because it can hold a razor-sharp edge very easily.  I accidentally cut myself on a fin, so be very careful with them!

After the 54mm motor mount tube was cured, I epoxied on the centering rings, followed by the fins.  I applied the fins next so I could get good fillets on the fin-motor mount joint for maximum strength.  PML specifies you to make tabs with cellophane tape on the aft centering ring and then to pull it off and make internal fillets using a long stick.  I thought, "No way!"  The body tube diameter is 2.560 inches and the motor mount tube diameter is 2.145 inches.  That leaves 0.2075 inches for me to place an epoxy covered stick in there and get "fillets" on the motor mount tube.  I just decided to assemble the motor mount tube as a whole and then slide it into the booster tube as one whole unit.  To do this, I cut out the fin slots all the way to the back.  Here is where my problems began.

When the fins were cured, I took the recovery strap and epoxied it onto the MMT.  I wasn't totally safe with this, so for "calculated overkill" (thank you Carl) I took a piece of 9 oz. fiberglass and glassed the strap to the tube.  I don't think that it will break now...

After I attached the strap, I filleted the fins to the motor mount tube using 30 minute epoxy.  Then I tried to insert the unit into the fin slots.  Unfortunately, the unit (now firmly epoxied together) didn't fit!  I checked the alignment of the fins, they were OK.  It must have been the body tube.  I ground out one of the fin slots using a Dremel sanding disk.  It still didn't fit.  So I checked the shape of the body tube.  

It was out of round, looking like this:

Well, I ended up taking the tube and briefly holding it over the stove to melt it, and then pressing it back into place using a steel tube and a coupler as a form.  It still wasn't exactly right, so after I glued in the fin can, I put a wrap of 3/8" fiberglass tape around the back of the body tube and epoxied it on.  That disaster successfully averted, onto the next step.

Since I don't like pistons (especially in Quantum Tube rockets where the fit is all but questionable), I decided to skip this and just let the rocket fly without it (a la Rocketman). 

The next step that I did was to assemble the payload section.  I am assembling the PS stock, so I simply assembled the coupler/bulkplate assembly and epoxied it into the upper tube.  Simple enough, because I am tired of building dual deployment rockets that take 2 hours to prep.  There is a pattern for an ALTACC in the payload bay, though, to allow for backup electronics.

I forgot to describe what I am using for motor retention.  I took the bottom centering ring before I epoxied it on and made two small gouges in the outside of it, approximately 180º apart.  Then I bent two clips out of brass sized to fit the various sizes of aft closures that I plan to fly in this rocket (29 Consumer, 29HPR, 38HPR, 54HPR).  After all this was completed and after assembling the rocket, I inserted the clips, and drilled a hole through the motor mount and through the clip.  A screw goes through this hole and through the clip, providing positive motor retention.  This is the same system used on my Vulcanite.  I have since switched over to an AeroPack 38mm retainer on the 38mm KS adapter, because I rarely plan to fly this rocket on 54mm motors.

One last note on recovery.  The Quasar came stock with a 36 inch parachute.  Since I'm lazy, I will just use this and blow it at the top.  There's also a flame shield in the rocket and a Nomex protector on the shock cord.  The Quasar also came stock with 1/2 inch tubular nylon for recovery!  I was amazed!  I wish LOC did this too.

Conclusion

This is a good rocket kit to buy, but because of the Quantum Tubing, it scored lower marks with me.  If I had to do it again, I would replace the QT with glassed phenolic.  Of course, that is only to suit my flying style- others would probably be ok with QT.  Other than that, I have no complaints about the rocket.  It is a great looking bird when finished and makes a great companion to my Laser/LOC.