A most unusual build - Astron Trident

[BSNW]

I have a few days off from work and the weather kinda stinks for the bicycle, so I thought it was a good time to pull this out of the back of my closet.

Does anyone remember Pimp Daddy Rocketry? This should be fun as in all the years I have been going to launches, I have only seen ONE Trident at a launch. Impressive design. Also LOVE all the balsa cones and utter lack of plastic parts.

Below are obligatory photos before THE-BAG-IS-OPENED. DUM-DUM.......DUMMMMM!!!

 

[Hobie1dog]

I've never heard of that rocket company

 

[Back_at_it]

WOW!!. I forgot all about this guy. I bought a couple of rockets from him but it's been close to 15 yrs. or more. Nice stuff and as I recall it was pretty affordable back in the day.

 

[Huxter]

Looks like a fun build. Good luck!

Pimp Daddy Rocketry had some really great kits. They've been gone for a number of years now. I got their Cassiopea, Starlab, and the Andromeda. Pretty decent kits too.

 

[BSNW]

I am going to really enjoy this build (I hope). Love the style of this rocket. I am already thinking of a HP upscale. Will also think that through as I build this one.

This will be a slow thread as I don't have time at the hobby table like I used to. BTW: I also have a Pimp Daddy Super Orbital Transport. That kit has a set of laser cut fins and balsa from BMS. Good times.

Andrew

 

[les]

Love the 'dent. I've built 4 different size ones....

 

[Joekeyo]

I have an astron explorer. Similar design.

 

[CoolRockets]

Where can I find this guy

 

[BSNW]

Well I actually had some time today to open the bag and get to it.
One of the most striking thing about this kit and its copied older instructions, is that there are actually WRITTEN instructions! They are very detailed. I have attached a photo of the instructions below. When they are written along with a diagram, there is often little ambiguity. IMHO it is a thing of beauty.... ANYHOO......off we go!

 

[mbeels]

This looks like a great builders kit of an awesome design. Cool!

 

[BSNW]

So as you can see from step #1 they have you seal the bases of all the nose cones. This is for the preservation of the balsa from the hot ejection gasses. Instructions called for wood/white glue. I instead did what I usually do and saturate the base of the cone with THIN CA. It soaks in like water and it often wicks all the way through the cone to the tip. This hardens the cone and seals the wood.
Lordy, there are a lot of cones in this kit!

 

[BSNW]

This looks like a great builders kit of an awesome design. Cool!

INDEED IT IS! no pre-cut fins or tubes. This is a dream! This is right out of "the good old days" HA!
Andrew

 

[BSNW]

Next on the instructions were to measure, mark and cut all the vents in all the tubes (5). This took long and is crucial to do correctly as everything has to line up when everything is cut.

It is so funny, how I have to remember to have a "lighter touch" when I start a model. I just completed a large 5.5" - 7 foot tall project that launched on L and M motors. The process is a tad more "physical". However, when slicing BT-5 tubes and trimming balsa, things need to get more "delicate". This is why I like both model and Large projects. Both are challenging in their own ways.

ANYWAY, I digress. The tube marking guide needs to be cut out and I found it interesting.

 

[BSNW]

The instructions called for the slots that need to be cut and sealed together to be only 3/32 or a little over 2mm!

(side note, there is NO metric in the instructions! I find this to be a slight historical interest/point... Lordy...metric = base ten, meaning simply move the decimal point. What the hell is 3/32 or some other weird fraction and you have to reduce?.....oops I digress a lot....SORRY).

I ended up converting to metric and cutting pieces of tape to the dimensions I needed and simply sliced them out......slowly . I then sanded and saturated the area with thin CA.

BTW: Notice my first vent/hole is slightly off the center line!!! CRAP! I will figure something out.....having fun here having fun....

 

[BSNW]

I am embarrassed to ask this! but does anyone know if this was originally and Estes Kit or a Centuri kit? When was this kit originally released?

Thanks for any input on this.

Andrew

 

[BSNW]

So I think I am done for the night.

The instructions said to glue on all the nose cones in their proper places. Before I did that, I put thin CA on all the vents. They look big in the photos, but they are small as this is BT-5.

I noticed either the nose cones swelled a bit OR they were turned a little thick. I had to do a lot of sanding on the shoulders to get them to fit. ALSO, if you look closely, you will see I will have to sand the main cones down where they but up against the tubes. The coned seem to "bulb out" a bit preventing a flush fit. This is not a big deal. You can see what I mean in the photos.

Happy New Year Everyone.

 

[Blast it Tom!]

I think that "bulbing" of balsa nose cones is almost endemic - I don't know if I've ever had one that I didn't have to sand to a nice, smooth tangent. Then some CWF and 400 grit and hopefully you can't even see the grain! Nice start here, indeed, have fun and Happy New Year!

 

[tsmith1315]

I am embarrassed to ask this! but does anyone know if this was originally and Estes Kit or a Centuri kit? When was this kit originally released?

Astron was Vern's word. The Trident was in the earliest catalog I remember having, the 1971 with that glorious Interceptor shot on the cover. Let's look at Sven's site to see how far back...



edit: 1968 is the first instance I see in the Estes catalog:
https://www.ninfinger.org/rockets/nostalgia/68estp20.html


re-edit: and the page from that great 1971 catalog:
https://www.ninfinger.org/rockets/catalogs/estes711/711est48.html

 

[neil_w]

I'm a little nervous to see that you CAed the vents. You can't use wood glue once you've soaked the paper in CA. Creating very solid, filleted joints on ducted models like this is key to making sure that they don't blow apart from the ejection charge.

 

[BEC]

As @tsmith1315 noted, the Trident first appeared in the 1968 Estes catalog.

I share @neil_w’s concern about CA on the slots and how you’re going to get good sealed and filleted joints now. They are crucial….but I will also say from having built a reproduction K-33 myself cutting my own slots that a strong ejection charge can blow it apart another way. This is my first Trident. I didn’t realize that it was damaged until after it was recovered as the ejection charge had enough force to eject the parachute anyway.



I later built a Semroc Retro-Repro Trident that had the fins and the gas passages laser cut. Those slots were wider (some clever changes in the design made that work) and that model has over two dozen flights on it with no issues of this sort. When you started this thread I checked and while eRockets.biz shows the Trident kit they are also shown as out of stock. I don’t know how hard Randy would need to be poked to run whatever parts he needs to make a few more and sell them.

 

[Blast it Tom!]

So would a good 3300-3900 psi epoxy work over the CA around the vents? I'm nuts, but this one hit my "build this" nerve, and CA'in the vents is likely something I would have done were it not for @neil_w and @BEC.

It looks like you might be able to get it in pieces from erockets. Instructions, decals, fins and centering ring sets are available. You might have to go old-school and cut the vents yourself, though, so you'd need a guide for that; and of course you'd have to order all the tubes, nosecones, laundry, etc. But I'll bet it can be done.

I can't help it. I like a clean, unusual design. This is that.

 

[Oldschool77]

I share BEC's pain. My 24mm upscale blew out just like his did after many flights. The parts are bagged waiting for a rebuild.

 

[BEC]

@Oldschool77 Sadly, that first Trident of mine blew apart like that on its second or third flight (I’ll need to go back to my early logbooks to see — it was over 10 years ago).

@Blast it Tom! The main thing is to get a good joint with a good seal at the gas passage slots, so the gases don’t leak out through the joints. Epoxy would certainly work.

I absolutely agree this is a lovely interesting design from the mind of Gene Street. It was one of those that I wished I could afford as a kid at that whopping $4 price. I think the most expensive kit I ever built in my first rocketry period was probably a Cobra…. As for cloning it, the main thing is that it uses nine balsa nose cones. That ain’t cheap these days. But there are no peculiar parts really, just some clever use of RA-2050 rings. So from the instructions up on JimZ (http://spacemodeling.org/jimz/estes/k-33.pdf) and ordering the parts from your favorite sources, it can be done. My first one was one of Semroc’s “x-kits”, where you got a bag of parts but had to go get the instructions elsewhere (the aforementioned JimZ site). The later one (Semroc KV-77) with all the laser cutting was a “retro-repro”, which included some additional jigs to line things up but save for three JT-5Cs and using two shorter tubes for each of the BT-5 sections, it was faithful to the original in most every detail.

Everyone always to see it fly when I bring out the current one, and one can’t beat the wadding-less prep for flight (though I usually put one square in anyway).

 

[JRL303]

Really nice build. Do it the way you want. Ca, blah blah blah... Enjoy your own way of building.

 

[dpower]

Nice, don't see too many PDR build threads. IIRC, some folks have added small balsa wedges along the rectangular vents to improve seal & strength. The Semroc kit instructions state: "If there is a gap at any joint, place a small sliver of balsa over the gap to prevent glue from filling the slots." Anyhow, I'm enjoying this thread!

 

[BSNW]

Hello All!

HAPPY NEW YEAR! THANK YOU for all the info on this kit and your comments!

I was able to do some more today! I ended up making the motor mount. I also sanded all the tube/cone joints to make for a better fit. I also coated the entire inside of the lower section holding the motor mount with thin CA for added protection. Note that any surface that has CA on it is sanded. This creates a nice bonding surface. I use thin CA to strengthen cardboard all the time and it has worked swimmingly. Also notice the nose cone shoulder on the bottom section. My measurements were indeed correct, but for some reason, the shoulder went over/under....whatever, the vent hole. I also do not use motor hooks, I am a tape thrust ring and friction fit kind of guy.

Anyhooo, see below

 

[BSNW]

I just want to also say that I don't consider myself a master modeler (I don't want to be), But I didn't "just fall off the turnip truck" either. I have built some tough kits with good success and actually flown the crap out of them. ANYWAY, this kit is tougher that it looks. I had a big "gotcha".....well....two of them. HOWEVER, sometimes fixing the mistake is just as much fun! Remember? this is supposed to be fun!! (I have to tell myself that at times). I just got to say there is a lot of things that have to perfectly (kinda) line up when it comes time to the final assembly.....oops.

I went on to put everything together and found out that some of the vent holes, despite careful measuring and cutting did not line up on the rotational axis. No worries! as long as one has masking tape and RUM you are good to go!

The mistake and the fix is shown below. I then coated the seams with THICK CA and sanded smooth. You can ALSO see the fillet of CA on the other side of the tape. I did this for all joints/seals.

When it was all dry and sanded, I put the cone on and gave the motor tube a big puff and blew the nose cone across the room with no problems or restrictions (the dog wanted to get the cone and I had to dash for it!!! good times). I then put the cone back on and held it in place......NO LEAKS BABY!!

You will also see the final fillet later on.

 

[StreuB1]

For ducts or passthroughs, I always CA the paper and then use 5min epoxy on the area to create a strong joint. It will never blow apart with CA and epoxy.

 

[BSNW]

Now on to the final fillets for the air-frames.

I have gone into much detail on how I do fillets with construction adhesive in past build threads (see my Estes Conquest build thread for just one example). I wont rehash that here. But it works great and is clean, cheap and extremely strong (I used it on one of my largest 5.5" projects that went super sonic). It is water soluble which is awesome in many ways.

The photos show it WET. after I smoothed it down with my finger dipped in water. This makes it glass smooth. When it dries it looses half of its mass and size and smooths out even more. This is glue is now the strongest part of the whole rocket and was only used to smooth out the appearance. After sanding-priming-sanding-painting-sand#3-final paint it will look pretty okay I think!

I didn't have leaks before, now there is no chance.

This kit was/is delightfully challenging. I agree with a previous comment that the design is very unique. I find the fin shape elegant. More to come!

 

[BSNW]

I do appreciate the concern about my use of CA and the venting. I did see the instructions calling for only a 3/32 (0.224 cm) wide vent. I thought this was crazy talk (small).

I did not include in the thread text that I indeed widened (doubled) the vent widths. If you look at my photos you can see that they got wider. I also think if the model develops restrictions in airflow....like from the inner wrapping coming de-laminated or loose; it will cause an air restriction and then a side to blow out. This is also why I put CA on the edges to hold the paper down after a number of ejection blasts.

I also cannot mitigate from the occasional Estes "Bonus 3X" ejection charge we all have seen at times. I am pretty confident in the joints and seals. If it blows apart I will take a photo of the tragedy and post here.

Thanks for the concern.