Recently I finished one of the new upscale Gyrocs, AKA the Tazz, and put it up for its first flight this past Monday. I was pleased that it flew pretty straight for a “Gyroc” even on a C and actually went a little higher than the 700 feet the face card (and 2020 catalog page) say it would go. I verified this by carrying an FS Mini altimeter aboard the model.

However, during the build I ran into a couple of little “gotchas”. The first one involves the fin-to-flap hinges.

The flaps are hinged on both sides with what amounts to thin clear sticker stock (shapes precut to fit). On one side, the hinge material just goes from the top of one part to the top of the other. On the bottom, however, the hinge material goes from the bottom of the fixed fin to the TE to the LE of the flap to the bottom of the flap. Those of you who have used tape hinges on small RC airplanes have probably seen something like this. However, if you haven’t (or if you forget, as I did) that some space between the surfaces needs to be left to make room for those two thicknesses of of hinge material, if you butt the two parts together and put the top hinge material on, you won’t be able to get the flaps all the way parallel with the fins after putting the bottom hinge material on.

Of course what one needs to do is leave about 1/32 of an inch gap between when putting the top portion on and then exercise a little care installing the bottom piece as it wraps from flap across the edges to the fin. Or, perhaps more simply, do the BOTTOM first instead of the top.

This is lots of words. The first attachment is a diagram I found with a quick search. If you imagine the “elevon” and the “wing” are both the same thickness and the “elevon” is not tapered, then you can see what I’ve clumsily tried to explain.

Because I missed this until I’d done it, I wound up replacing the precut top hinge material with strips of Scotch Multi-Task clear tape (which I have used successfully for years for tape hinges on small RC airplanes) and it is working just fine.

I came across the second one after I’d painted it and was getting ready to put on the decals. Tazz rear-ejects the motor mount with a streamer wrapped around it in pretty much the same fashion as the repro Gyroc (which is the original Gyroc size but uses 13mm motors) from Semroc. The pieces involved in this (and holding the flaps in line during boost) are two plastic rings, one attached to the base of the body tube and one attached to the motor mount assembly right behind the aft centering ring. This latter part has a tab that engages a mating guide on the body-mounted part which keeps the flaps aligned. The body-mounted ring sits on the outside of the body and is about 3/32 of an inch thick.

The “gotcha” is that there is no standoff for the launch lug, so the launch rod rides on the the ring, takes advantage of the fact that Estes launch lugs are a fairly loose fit on a 1/8-inch rod, and then rides on the base of the nose cone. It doesn’t bind so much that the model wouldn’t get off the rod (though a rod that’s a full 1/8-inch diameter binds a bit more than an Estes rod). But still, that struck me as less than ideal.

Since my model was already built and painted, my solution was to grab a cordless Dremel tool, the small diameter sanding mandrel with a fine-grit drum attached and relieve the ring where the rod passes over it. See the second attached picture.

The obvious thing to do while building it is to cut a strip from the fin scraps the length of the launch lug and about 1/8 inch wide and use it as a standoff for the launch lug.

As I say it put in a nice first flight on a C6-3 on Monday to 715 feet (temperature corrected). It might actually benefit from using a C6-5. The pod ejected and its streamer unrolled as it should while the flaps deployed and the model came down just like a Tazz should (just like the Gyroc). The motor pod fell faster and landed nearer to the launch point but the two parts were not that far apart.

The last two pictures are an “on the pad” just before the first flight and the model as I came to it in the squishy soft ground of Sixty Acres after several days of rain. The mud went to about two inches up the nose cone, even though the model without the motor pod only weighs 1.1 ounces.

Oh—and before someone (shreadvector, perhaps) chastises me for calling the model “Tazz” rather than “TAZZ”, while it’s all caps on the face card and you could interpret the decal that way, it’s also shown as “Tazz” in the 2020 catalog both places the model appears there.

Related to THAT - there’s some confusion about recommended motors. The face card calls out C6-3, B6-2 or B6-4 or A8-3. The catalog calls out B4-4 and B6-4, C6-5 and C6-7 as well as A8-3. C6-7 makes no sense, but based on the one flight I’ve had so far, C6-5 and 4-second delay Bs would likely work well. My model weighs 1.35 ounce sans motor (and altimeter).

Attached Thumbnails

       

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

The picture of it screwed into the ground is priceless.

Bernard,

Great write-up. Thanks for the detail. I haven’t bought a Tazz yet (or even a TAZZ. ), but glad to know about the placement of the hinge material, and it makes mores sense to me seeing your diagram. Also good to know about the need for a launch lug standoff.

__________________
Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, EAC Firecat (Mini HoJo bash), Scorpius, DBRM
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp

This kit is on my future buy list - though I don’t have my Semroc Gyroc built yet so it’s not going to the top of the pile. Great tip on the hinges, thanks for the diagram, that made it crystal clear how to rig the hinges. Good looking finished rocket!

That model is begging for a barber pole paint job.

__________________
I love sanding.

Thanks Bernard for the heads up on the build!

Your Tazz looks great, I have one in my build pile and thank you for the heads up. What did you use to fill/seal the balsa parts?

You know, I'm not sure. I think I used the water-based Valspar sanding sealer that I bought years ago and have slowly been working through. Probably three coats with sanding with 220 or 400 in between. Paint is one coat Rusto 2x primer, in this case followed with Rusto 2x gloss white (black on the nose cone) within the 1 hour recoat window for the primer. Painting weather is scarce this time of year around here so I've rushed several models this way lately. The downside of doing that is there's no sanding of anything that the primer raises and some surfaces, notably the inboard sides of the "rudders" are pretty rough.

I just got back into using the Brodak sanding sealer that I've had for awhile and the three models that are in primer right now (New Way Big Bessie, Estes Sterling Silver, Estes Mini-Bertha clone) were done with that instead. The fins on all of these look much better.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE