LOC/Precision Graduator

LOC/Precision - Graduator {Kit} (PK-16) [1986-]

Contributed by Todd Harrison

Diameter: 2.63 inches
Length: 40.00 inches
Manufacturer: LOC/Precision

LOC Graduator review is provided courtesy of:
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PicThis rocket is a popular LOC kit for people new to composite motors. I liked the looks of the rocket and was in need for a new kit in that power range (D-G). The Graduator came promptly and packed well, however, the shipping company had still managed to kink the body tube. I contacted Barry, the new owner of LOC, and he shipped out another tube without question that also arrived on my doorstep in a timely fashion. 

Now that all the parts were here it was time to build! After test fitting the parts (which were all snug fits) and looking over the instructions (one-sided/brief), I decided to bevel the edges of the plywood fins. I swept each side of the fin’s edges through a grinder too create a nice bevel with minimal work. I lightly sanded them to remove any imperfections from the grinder. Next came the motor mount assembly. This consists of 2 centering rings, a 29mm tube, a baffle, and 24/29 motor adapter. I attached the centering rings with 15min epoxy after they’d been lightly sanded. I opted to not epoxy in the baffle unit since I plan to use some longer 29mm motors and the baffle might prevent them from being inserted. However, this is a nice addition to the kit that is not usually seen in similar kits by other manufactures. Next, the motor mount was slid into the tube and secured by 15min epoxy. This rocket was going to be the testbed for a fillet technique that I’d read about. After the motor mount was dry I popped one fin into the slot and dammed up the forward and rear end of the fin root with masking tape and wood. The rocket is placed at a 5 degree angle (nose end down) and the fin should be at approximately a 45 degree angle with the floor. I then mixed up a small (one pump) batch of West Systems epoxy (105/206). PicThe epoxy is thin and runs easily. I poured a small amount into the fin root near the aft dam and it slowly flows down the root. Once it reaches the forward end, the rocket is placed horizontal to the ground and the epoxy will level. Some will seep into the tiny void between the slot edge and the fin which locks the fin in the slot. This is critical and convenient because the fins don’t extend all the way to the motor mount so they need this extra reinforcement. A second dose of epoxy might be needed since some has flowed inside the tube. Once cured, the fillet is in near perfect and glass smooth. This process is repeated for each of the other 5 roots. This process is quite time consuming, however, the outcome is very rewarding. Once the fin can was complete I moved onto the recovery system. This kit comes with the typical LOC shock cord mount, a nylon string. It is looped, knotted and epoxied to the inside of the airframe. At first glance, this type of shock cord mount seems insufficient, but I’ve personally never had one fail. This was again epoxied with 15min. The kit comes with an elastic shock cord that attaches to the nylon string and nosecone eyelet. The parachute is a standard one piece 18” black nylon chute. The final construction step was to attach the 1/4” launch lugs to the airframe. It needed to be cut in two and sanded to properly support the rocket. 

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For finishing, I first filled and sanded any ruts with Bondo filler and once complete I applied a coat of gray primer. I painted the fin can and nosecone gloss black and the mid section a cranberry red. 

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For the first flight I loaded her up with a F52. I attached a Nomex® heat shield (Courtesy of Dave Pacheco) to the shock cord. The 1/4” rod was grungy and a tight fit so I move her down to a 3/16” which was just slightly loose. At liftoff she jumped off the pad and headed into the wind. The chute deployed on cue and brought her home safely. Despite the 10mph winds the Graduator was recovered fairly close to the pad for a successful flight. Next, I headed down to Pennsylvania in March to launch with PARA. I was in a good mood and decided to give her a ride on an H128. I prepped the motor the night before and headed out to the site at about 9:30 the next morning. I got caught up watching others fly and while prepping the Graduator’s recovery system at about 10:45 the winds started to kick up. I was finally ready to launch but when I got out to the pad the rod was wayyyy to tight. I had to run back to the car and sand the lugs. I realized that the uppper lug was slightly off center which wasn’t helping my cause. I removed the lug and whipped out the 5 minute epoxy. While she was drying the winds were getting worse and they eventually the range was shut down. Bummer! The weather up in New England has been horrendous and I still have the H128 loaded hoping to launch eventually. However, One weekend I decided to go out with a couple buddies at launch locally. I loaded up a G35 because I didn’t want to launch the H128 at an unorganized launch and the site was a tad bit too small. I flew the Graduator off a 3/16” rod once again. She roared off the pad on a nice plume of Econojet smoke. Deployment was right at apogee and she came down gently not very far away. There was absolutely no damage. 

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This is a great kit, but if you do decide to purchase it, I have several suggestions. The cardboard lugs must be cut in two, so you should replace them with 1/4” brass or copper piping. This is the second time I’ve had trouble with lugs. Many people would also recommend modifying the fins so they go all the way to the motor mount. However, for this kit I do not think it is necessary. If you put a little extra effort into the fillets and reinforcement, the fin can will be rock-solid and will stand up to a lot of beatings. In conclusion, this is a great quality kit that is well worth the money and it’s an excellent flier! 

 

Written and submitted by Todd Harrison for Rocketry Online -- Copyright 1996-2000 

Other Reviews
  • LOC/Precision Graduator By Mark Trotter

    (by Mark Trotter)  This is a great kit to get you into the more advanced, mid-power rocket kits, but I would still recommend getting a novice kit first. The Graduator has the great feature of through-the-wall tubing which decreases the time and effort for you. It also comes with the LOC MMA-1 motor adapter to fly it on 24mm motors. The only problem, there is no type of "motor ...

  • LOC/Precision Graduator By John Hogan

    Brief The Graduator is an excellent rocket for those wishing to get into mid/high powered flight Construction The tubing, fins and everything were of excellent quality. The instructions were brief (few illustrations), but adequate. The preslotted tubing made fin installation straightforward, and all parts fit together nicely. I highly recommend reinforcing the fins so that they are ...

Flights

Comments:

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D.H. (September 1, 1999)
My LOC Graduator is now 7 years old and still flying. It has flown on engines from D12-3 (frighteningly low altitude at ejection) to G40-7 (WOW!!!!). It has had its share of abuse from over 30 launches and is still going strong. The only change I would make is to have the fins go all the way to the motot mount. Easy to construct and fly. The perfect first mid power rocket.
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R.T. (November 1, 1999)
In short, the Graduator was my first big rocket, and still my favorite. The Rocket can really get up there, my best launches were on an F101T-5 and a G80T-10. I have put it up on a D12-3, and almost killed the LCO, or at least scared him! I have found that one can use a 12' chute for the G's and H's, but make sure the fins are very strong.
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J.C. (February 1, 2000)
Great kit. I had a good time building it. I added a motor Retention system, I set it up to handle the longest motor I had, (29mm Areotech RMS case). I also was too scared to use the wall mounted shock cord mount.(upon reflection I'm sure that the 6ft plus shock cord would absorb most anything, thus preventing any potential "zippering"). I made my own mount using the same 1/4" plywood that the fins are made of. I shaped it to fit, drilled holes in it and added an eye bolt. I do wish this kit had fins that went all the way to the motor mount tube. But they seem strong enough to me. I felt it was rather deceptive not to mention that the Loc/Precision kits don't come with decals. I made my own using colored self-adhesive sheets sold at hobby shops that sell model airplanes. They're great and come in all kinds of colors. Overall I'll give this kit a 3.5 rating out of 5. It would need several things to get a 5. 1.) motor retention system. 2.) Center-ring mounted shock cord. 3.)through the wall to engine tube fins. I will nevertheless still buy more of the Loc/Precision kits. If, however, let's say that Areotech made all the same rockets that Loc/Precision did, I'd buy the Areotech every time, even for a 25% price premium.
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G.B. (May 1, 2000)
Adding an engine block to the kit would limit your choice of motors. All you have to do is wrap 1/2-inch electrical tape (takes heat better than masking tape) on the aft end of the motor until it becomes slightly greater in diameter than the motor tube. That keeps it from kicking forward. A simple way to keep it from kicking aft upon ejection that I used is to install a pair of blind nuts (T-nuts) in the aft ring that take No. 6 screws. Wire is attached to one screw, wrapped around the engine nozzle, and secured to the other screw. Simple, cheap and effective. But you have to install the nuts before you install the engine mount into the body tube. And be sure to epoxy the nuts in place.
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K.W. (June 1, 2000)
I'll agree with the other posters that the Graduator is a great kit to get started with in mid power. I chose it myself based on some suggestions from other folks and I'm glad I did. Construction is straight forward. Luckily I had heard about Kaplow Klips before I started and incorporated them in the rear centering ring. I don't know why LOC doesn't include them in the kit or at least suggest their use. The parts are cheap enough and available at any hardware store. I also built in a parachute compartment in the forward end of the body tube so I wouldm't have to use wadding. This was a section of 1 3/4" diameter mailing tube, long enough to hold the supplied 18" chute and shock cord. I epoxied a spruce bulkhead at the rear and coated it with epoxy. I centered in the body tube with three strips of 3/16" thick spruce. The ends of the LOC shock cord mounting loop were epoxied into the spacer fillets and the whole assembly was epoxied into the body tube far enough in to let the nose cone slip inside. I flew it about 8 times (on E16s, F20s, F22s, F52s and a G33) like this until I had a bonus delay on an E16-4 and it lawn darted. I rebuilt it with a new section of LOC body tube and incorporated anti-zipper design into the coupler. (This concept was covered in Sport Rocketry a while back) This is essentially a tube coupler with a bulkhead on each end. There are holes drilled in the bulkheads so that the holes don't line up. It acts as an ejection baffle. I put an eyebolt in the top coupler and the chute goes in the forward section of tube. So far I've not had any recovery problems or chute damage. It's also survived a lake landing. It is now too heavy to fly on E's. My favorite motor for this bird is the F20 and F23 Econojets. I recommend this kit for a first mid power bird. It flies on a variety of motors and has the flexibility of a 29mm motor tube and an adapter that comes with the kit.
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J.S. (January 1, 2001)
Graduator is a great first rocket for mid-power. It's inexpensive, forgiving, and fairly stout. It would be nice if LOC would do something about motor retention, since a mid-power newbie tends to learn about such things the hard way. I do wish the fin tabs continued to the motor mount. Even with the TTW fin mounting, I knocked fins loose on two different occasions. The parachute choice seems to assume a small field. But you'd better not be in a small field if you launch your Graduator on a G motor! If anybody finds mine, please let me know. @#$%! trees.
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S.B. (January 1, 2001)
I agree with Mark. The Graduator is a simple kit to build, with enough room (barely) in the rear centering ring for a retention system. I didn't put one in and haven't had trouble with friction fitting motors. I even friction fit a H-128 for my level one flight when my cert 1 rocket died on it's test flight, and everything worked fine. A fun rocket to build and fly!
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M.R (January 1, 2001)
I really enjoyed building my Graduator. I agree that it's a good first rocket to get into mid-power rocketry. My kit went together really well, but I wish I would have thought about motor retention before assembling it. I retrofitted mine with something similar to a "Kaplow Klip" which works great for both single use and RMS motors. I used a sealer on the fins before painting, and didn't get any grain, but the appearance of the finish came out noticeably different from the body tube.  I finished mine with a uniform color of Pactra Candy Purple, and call it the "Purple Propellant Eater". I've flown F and G reloads, but I've found that the suggested 10 second delay is a little too long. All in all, the Graduator is a great rocket to build and fly!
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J.S. (August 1, 2001)
The rocket is very stable in flight. I used a H90 and flew great. The only thing that should be changed is the through the wall fin design. It should be all the way through to the motor mount, so it has more strength. One could also put dowels inside the airframe and epoxy them to the fins. This would be better than nothing.
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P.V. (December 15, 2001)
I bought this rocket from DiscountHobbyCenter.com and I got the new version with fins that go all the way to the motor mount. It was a very easy kit to build, it flies great too. My favorite motors for it are F23 and G38 BlackMax motors.
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G.B. (August 30, 2002)
Many posting opinions here on the Graduator have wished for through the wall to the motor mount fin tabs. According to the LOC Web site, the kit now includes that! It's refreshing to have a company respond to consumers' calls for improvement. Now if only Estes would do something about those lousy shock cords ...
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J.S. (April 26, 2003)
I highly recommend the Graduator. It's attractive, very stable, and reasonably easy to build. The parts are all of top quality. I made a few modifications to the kit: I added a thrust ring and a Bourne Again Rocketry Motor Anchor (since I'm uncomfortable with the idea of using tape to retain the motor in a rocket as large as this one). I also skipped the LOC shock cord mount and instead mounted the shock cord with a piece of Kevlar® attached to the forward centering ring. Another good motor for the Graduator is the F20-4 Econojet. Compared to those of an AeroTech or Estes kit, the instructions are terse and have few illustrations. If you are completely new to mid-power, it might be a good idea to build an AeroTech rocket or two before you try a LOC/Precision kit.
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(June 16, 2004)
To avoid being ripped off or scammed from DicountHobbyCenter.com, check the Better Business Bureau to see at least 15 COMPLAINTS against this firm. We are seeking legal action ourselves. Our research indicates disturbing findings. Check it out for yourself if you don't believe us. After we get through with this firm, there will not be any hobbies to buy from them and you can rest safe. Caveat Emptor Greetings to all.
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B.P (March 18, 2008)
This was my level 1 rocket, flew great on an H180 medium. has also flown on an H128, H97. H128 was probably my favorite not too high. The only problem was that the rocket would always land on one fin first. finally broke off edge. this would probably be a good place for some fiberglass reinforcement.

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