L2 scratch built 3" FrenzyXL clone that was going to be a Thor clone.

Couple of months back I got sidetracked from my L2 project which at that time was going to be a BSD Thor clone in 3" Loc Airframe, however the Twin Crayon rocket builds kinda stalled that for a while. So I already had ordered some parts for the Thor clone and got held up.

Fast forward to a few weeks ago:

The same day I started the Crayon rockets I also cut the blanks for the bulkheads and CRs. In the beginning we call this day one, on day one I also glassed the Loc 3" airframes using the method from the video by John Coker with a couple of wraps of 2oz FG from Raka Inc, and using US composites 635 epoxy.



Day 2 here are the tubes wrapped in acetate ready to unwrap.

Fast forward to last weekend and I finally got some time to work on things.

First up was to make some plugs for the airframes so I could sand them faster due to the poor job of glassing the tubes (it was my first attempt), there were dry areas of cloth, however the excess resin created air pockets in the surface requiring a lot of sanding and filling. Using some scrap wood pine from around the shop I turned a couple of plugs that will hold 3", 54mm, and 38mm between the centers on my ancient Craftsman woodworking lathe.


Attack of the red crap, a lot of Bondo spot and glazing putty was applied and most of it sanded back off, then a coat of primer was applied (yes I am now aware that with glazing putty priming should be done first). The primer was sanded off, and some more glazing putty used, a tiny bit this time.


The plugs make rough sanding a breeze, takes about 5-10 minutes to strip the excess putty off.

Day 3

Extended the AVBay coupler by 3", using a mailing tube for a "coupler" kinda like a Loc Stiffy, and then 3 wraps of 7oz. fiberglass on the interior, it might be just a bit overbuilt. I was concerned that the 6" coupler might not be enough to handle 54mm motors, not a problem now.


The zipperless coupler was also given 3 wraps of 7oz glass.


The two airframes with the first coat of primer, and that beautiful Pinnacle Nose cone from Giant Leap Rocketry.

Day 4 Yesterday


Trimmed the bottom off the nose cone in anticipation of conversion to a NC AV-bay for a tracker or something.
Cut and trimmed Bulkheads for coupler AV-bay, and for NC bay, I also cut the fins from 3mm BB in anticipation of glassing them tomorrow.


Today was the day I decided which rocket to actually build a Thor clone or a Frenzy clone.

Day 5

What a day, got a very late start on things due to taking the family to the local hospitals Safe Kids Fair and grocery shopping. And then repairing 2 dining room chairs my wife picked up off of a Facebook trading/selling site.

Finally about 9pm-ish I got started glassing the fins. Each fin got a layer of 7oz and a layer of 2 oz glass per side. There is a sheet of acetate taped to the top my tablesaw (flatest spot in the who shop and least likely to move . After applying FG cloth, another sheet of acetate was put on top.


My press is a 40lb granite surface plate on top of a piece of 3/4 Melamine board, and inside the glove box (to protect the surface plate) is a chunk of 2" steel weighing about 15 lbs.


The two airframe tubes with the first and last coat of high build primer on them (Duplicolor 2 in 1 High Build), now the imperfections are the high spots, tomorrow looks to be more sanding.

Got some more work done today. All airframe sections are cut, along with the MMT, fins are cleaned up from the glassing process. Pretty much just a few CRs and a thrust plate to cut along with slots for the fins, then assembly begins, hoping to have it ready by June 15th for our June Swoosh event to do my L2 cert. I also weighed all the current parts to update my OR sim.

Got some more done on the L2 project today. It was all about Centering Rings today. All are cut and sanded to size.

There are three 3/16" rods that run through the centering rings, at least for the moment. I may after the CRs are glued to the MMT cut them away since their only purpose is for lining things up.

The rings are all slotted which took about 15 minutes with the router jig I have made for that purpose, the dowel holes in the rings also help with the slotting since I use a removable pin in the jig to index the slots. Visible next to the fin can is the Thrust plate with the retention t-nuts or whats left of the t-nuts after trimming them down on the grinder and belt sander. I may end up just using an Aeropack
which will solve a number of issues. Its finally starting to come together, hopefully tomorrow evening will be tacking the ring assembly together then marking and slotting the fin can.

You've been busy! Looks rock solid.

I REALLY like the sanding idea on the lathe. Makes me want a lathe even more now...

Back to work after a couple of days not getting anything done on the build.

Centering rings glued to motor mount tube, dowels are most likely temporary as they don't really serve any function at this point. Fins are dry fitted again just for the photo. Tomorrow will hopefully be slotting the fin can and filleting the non-fin sides of the CR's, except for the topmost CR which is butted up against the zipperless coupler. Due to the change in my plans of originally going with a 38mm MMT and now a 54mm the U-bolt will no longer work so I will be using the Kevlar loop to mmt method for shock cord attachment.




Fin can section dry fitted, everything so far has measured out properly, I haven't decided wether or not to trim the extra 1/4" off the MMT to leave it flush with the top of the zipperless.

Got a little more done today, tomorrow will really be fun because the fin can starts going together in a big way, permanently attaching fins and stuff.

Fin slots cut, the Dremel 543 cutting disk pictured in a previous post absolutely blasts through the fiberglass wraps and tube, took less than 10 mins to cut all 6 slots. It would have taken that long to get out my router and slotting jig and then set it up.



Nose Cone Av-Bay conversion CR epoxied in, eventually I will trim off the sections of t-nuts protruding into the opening.



CRs glued last night, and filleted tonight, the top ring doesn't get a fillet due to the fact the zipperless coupler butts up against it. Add the shock cord attachments with plenty of epoxy and a couple of wraps of scrap FG I had lying around.




Tomorrow will be loading the mmt assemby into the fin can and starting to put fins in permanently, adding the zipperless coupler. All the fins internal fillets will be injected Wildman style.

Guess I didn't post a pic of one of my new favorite rockety tools in my rotary tool arsenal the Dremel 543 cutting/shaping disk.

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DAllen said:

You've been busy! Looks rock solid.

I REALLY like the sanding idea on the lathe. Makes me want a lathe even more now...

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The lathe I have was free from my Father-in-Law, it took a lot of work to clean up from years of having sat outside under a tarp after they lost their shop/business. As lathes go it has lots of limitations, but for the basics it works great, these Craftsman lathes can usually be picked up for a song, however some parts are getting hard to come by and others are just not standard. The tapers are MT1 where most lathes this size use MT2, the thread on the drive side is 3/4-16 iirc, which while standard is not as common as some others and requires adapters to use some chucks and accesories. Its hard to beat the sanding on the lathe though its definitely fast, messy but fast.

Today might have just been the most productive one yet. Got lots of stuff done, and only been working on it for 10 days now.

AvBay nearly complete, just have to add the t-nuts for the button head screws that connect th coupler to the upper and lower airframes. Ejection charge wells were made on my drill press, and the aluminum rods I threaded. I really like building as much of the rocket as I can. The Schurter rotary switch will be along shortly from Missleworks, along with the shear pins and some Missleworks decals. Really not much to do except mount the altimeter, battery and switch. In an effort to eliminate wire connections the ejection igniters will wire directly to the altimeter, the wire will pass through the hole currently covered by the well nut ( I still have to file a small round notch for the wire).



Fin can getting there, all six fins are epoxied in place, tomorrow I will begin injecting the internal fillets. All fins were attached using CrazyJims double buttering method (as long as I understood it correctly). Weather was a bit on the warm side so I was able to to both sets of fins, the zipperless coupler, upper fin centering ring, and zipperless CR, and after everything set fairly solid the excess epoxy from the second fin set went into the lower fin CR. Visible in the picture is the block for the Rail Guide, I plan on using a few tiny screws with the ACME Conformal Rail Guide.



Middle member of my rocket recovery crew posing with the mostly assembled rocket he's 4 years old and usually beats everyone to the first flight of the day, after that he's worn out and has to recharge. He's really excited about rockets now, pretty soon I will get him a E2X or ARF type rocket to build, his older sister just built an Estes Skywriter (with assistance from Dad) and is itching to fly it, naturally this is the clubs month off.

qquake2k said:

I used to have that exact lathe. It's fairly long, which is nice when sanding tubes like you're doing. If you look hard enough, you should be able to find MT1 and 3/4-16 accessories.

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Grizzly carries most of what I would want or need, my real plan is to keep that one for simple projects and buy me one of Grizzlies newer flat bed styles with a duplicator attachment since I like to do real wood working and making multiple spindles that are the exact same would be nice, of course then I could duplicate any nose cone I so choose.

qquake2k said:

I had the big Harbor Freight flatbed lathe for several years, and it served me well. I now have the Jet variable speed with the bed extension. I've never used a duplicator, I'm curious as to how it would work on a nose cone.

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Makes two of us.

Yesterdays and Todays work.

External Fillets done and awaiting cleanup, then onto the priming filling and priming process a couple of more times this time with a white primer.



54mm to 38mm adapter built today, as well as NC primed so I can start filling the parting lines tomorrow.



Acme Conformal Rail Guides installed, lower RG will get some very small wood screws to reinforce the JB Weld it is attached with. RG and airframe FG was heavily scored with a x-acto knife, and 80 grit sandpaper prior to applying epoxy. The lower RG also has a wood block behind it to sink the screws into. Forward RG is just attached with epoxy, if anyone has had problems with these rail guides coming off with just epoxy attachment let me know please, I am avoiding putting anything inside the airframe as reinforcement to avoid any chance of snags since a 48" chute is fairly close fit in a 3" airframe.

rharshberger said:

Yesterdays and Todays work.

External Fillets done and awaiting cleanup, then onto the priming filling and priming process a couple of more times this time with a white primer.

View attachment 263901

54mm to 38mm adapter built today, as well as NC primed so I can start filling the parting lines tomorrow.

View attachment 263903

Acme Conformal Rail Guides installed, lower RG will get some very small wood screws to reinforce the JB Weld it is attached with. RG and airframe FG was heavily scored with a x-acto knife, and 80 grit sandpaper prior to applying epoxy. The lower RG also has a wood block behind it to sink the screws into. Forward RG is just attached with epoxy, if anyone has had problems with these rail guides coming off with just epoxy attachment let me know please, I am avoiding putting anything inside the airframe as reinforcement to avoid any chance of snags since a 48" chute is fairly close fit in a 3" airframe.

View attachment 263902

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The only time I used them was on a PML Endeavour made with Quantum tube. Nothing really sticks to QT anyway so I converted to Rail Buttons and never looked back. I also didn't like hard it was to line up the rail guides, buttons are so much easier. :wink:
If you decide to put reinforcement inside the recovery bay make it as thin as possible and cover it with aluminum tape. Aluminum tape will take the heat and you can get it to hug the contours while still laying flat.

Beautiful day in the desert for rocket work, was able to work with the big shop door open, as it was about 80F today, finally past the point of needing to use epoxy (YAY!), today was mostly fill, sand, prime, fill, sand, prime (you get the point). My order arrived from MissleWorks (awesome service from Jim Amos), so I was able to mostly finish the Av-Bay only a few reinforcement fillets to add to switch mount. Started building up the fillets on the motor adapter, I still have to run to the hardware store to get some motor clips.

It's finally starting to look like a rocket, once I am done with the priming its on to ground testing. I'm trying to have everything ready to go for my L2 attempt by Father's Day weekend when our club is holding is annual 3 day launch. Once I finally get the rocket done I will have more time to study for the test.

No new pictures today, just filling and priming. Its ready for ground testing prior to painting.

Its been a week or so since I've had time to work on my L2 project. Today was sort of productive as I installed the shear pins and completed the ground testing. Looks like 1g BP in the drogue section, and 1.5g BP in the Main Deployment bay. Neither was enough to pull the taped z-folds out of the shock cord much, the drogue section seperated about 6 feet or so and the main section popped about 10-15 pulling out one set of z-folds. It was all nice and gentle. Printed the decals on some decal paper I bought from Bare Metal Foil years ago, just waiting on them to dry so I can clear coat. The only ones I plan on using currently are the Frenzy XL3 and the CP and CG markers.

Are you still shooting for the L2 attempt for the Father's Day weekend?

o1d_dude said:

Are you still shooting for the L2 attempt for the Father's Day weekend?

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Yep, so far so good.

Okay, its been week or so since the last post. The vehicle has acquired paint, that was a chore in and of itself. The nose cone required a adhesion promoter (Duplicolor) to get the primer and paint to stick, but it turned out Ok, the paint was Walmarts HomeShades, White and Kelly Green, can't complain too much about the paint as it worked okay and seems to be well cured at this point (several days later). My L2 motor will be awaiting pickup at the launch, sending this rocket up on a Pro38-6G J354 White. Rocket weighs about 7.3lbs with motor (about 5.5lbs w/o motor). Sims to 4700ft.

The Red at the nozzle end is the 54mm to 38mm motor adapter.

Very nice! Good luck on the launch

Finally I can post the latest pics of my build. It been a couple of days since I was able to post last due to the server issues. The rocket is finally ready, its actually been flight ready for a couple of days. Tuesday I went down to a local sign shop and picked up some "scraps" of vinyl which still cost me $20. Made some patterns and cut my decals. The waterslide decals that I made failed most likely due to the inkjets printer since after 2 weeks they still are not fully dried, and they faded as they dried. So I just did the fin decals added a couple of black stripes and the chrome band in the middle which hopefully will help with visibility. The new main chute will actually be finished this morning we just have to attach the shroud lines. Hopefully all goes well and Saturday morning is the L2 flight. Depending on wind is wether the flight will be main at apogee or dual deploy.

That is some stunning finish work.

Thanks, its maiden flight will be at Pasco, WA this saturday at the Tri-Cities Rocketeers 3 day launch.

rharshberger said:

The waterslide decals that I made failed most likely due to the inkjets printer since after 2 weeks they still are not fully dried, and they faded as they dried.

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I made some water slide decals with an inkjet printer a few year ago and they turned out very good. I did buy the ink jet decal paper. After the inkjet ink dried a half hour or so, I coated them with Krylon Clear Coat paint.
The clear coat was the key to making them work. It sealed the inkjet ink and prevented the ink from being affected by the water when doing the water slide.

So I'm curious, what did you use for decal paper? Did you clear coat them? It should have worked, although the inkjet colors will never be as solid and vivid as vinyl is. If you used the inkjet decal paper and clear coated, I would be very interested in what my have cause the failure so I can avoid that in the future.

thanks....