Upscale Estes Plasma Probe

[EeebeeE]

About 2 years ago I built an Estes Plasma Probe for the heck of it because while I love to fly big rockets...I also love to fly little ones. And this one is just gorgeous. It flies exceptionally well on B6-4's and C6-5's. From the time I built it I had always wanted to upscale it. So when I bought the materials for my "Der Mad Max" I also added a section of 3" BlueTube for this design and had Upscale CNC cut both fin-ring sets at the same time to save on materials costs.

The original kit was 18.25" long and flew on 18mm motors. Forward section was BT20, Aft section was BT 50. Scaling it up to 3.01x almost perfectly scales the rocket to 4" and 3" airframe along with a 54mm motor tube. The motor tube diameter is critical because the aft section is exposed in the design. The upscale length

I have a 4:1 PML nosecone that scales perfectly. The only thing that does not scale properly is the 3"-4" transition available through LOC precision. The transition is about 1.5" too short in length. I suppose I could have one 3D printed, or I can fabricate it using the BlueTube. Haven't decided yet. I will either reach out to Stickershock for the vinyl decals or I will print my own waterslides.

Unlike Der Mad Max, this will be a slow sub-mach rocket that I will fly with longer burn motors and skidmarks. I want this to give a nice show. Here are images of the design.

 

[Nytrunner]

That's going to look really nice (those fins may make it hard to store though ).
What are you doing for fin material?

 

[EeebeeE]

Fins are 3/8" plywood, as are the rings.

 

[Nick@JET]

Love the photon probe, going to be very unique!

 

[EeebeeE]

Love the photon probe, going to be very unique!

This is the Plasma Probe. I also have an upscale design for the Photon Probe, but I am waiting until next build season. Then I might take it up to 6" in diameter, build it out of FG, and put an M in it.

 

[djs]

I would love an upscale photon probe and plasma probe.. except that I don't have the skills to make them

 

[EeebeeE]

If you can cut balsa fins with a razor knife then you can cut plywood with a saber saw.

 

[EeebeeE]

Finally got started on this bird. Trying to keep it as true to scale as possible but there will be a slight deviation with the transition. The LOC 4"-to 3" transition is about 1/2" too short, but I am going to use it anyway over having one 3D-Printed. The fins and rings were cut by Upscale CNC. I had to cut notches in the fin roots for the aft CR. No big deal.

The bigger challenge was getting the aft CR onto the motor tube with precisely a 3" overhang so that the fin roots on the aft section extended down to the very end of the MMT.


The Original scale was all square edges, but I decided to taper part of the leading edge because it will slightly increase performance and it will look kind of cool. This was done with my belt sander and manually sanding the corners. First with 60-grit, then with 220 grit.



Experience has told me that dowel on the end of high powered rocket fins needs to be as perfectly aligned as possible. Otherwise it will create stress by trying to warp the fin. Shredding may ensue. So I used rocketpoxy to glue the dowel in place, then compressed everything on the concrete floor with 20 lbs. of dead weight. I will fill the gaps with Rocket Poxy.


To give you an idea of scale, this is the original Plasma Probe against the upscaled fins.

 

[EeebeeE]

Mounting the fins is fairly straightfoward, though I want to do it in such a way that I can remove the fincan so I have more room to work with as I secure the fincan. So I sparingly add glue to the root so as not to adhere a fin to the airframe. The aft CR is glued into place, but the forward CR will not be until the fins are all glued to the MT.

Since this rocket has 4 fins, it is amazingly easy to align them. Glue two opposing fins to the mt with the airframe in place. Clamp a piece of angled aluminum to the trailing edges of the fins across the MT. Let the glue set, then glue on the other two fins. Alignment is nearly perfect.



The ribs went on very easily, though I think I got one a little crooked. Oh well.



Still need to work on the fin roots, but it is finished enough that I can compare it to the original.

 

[Nick@JET]

Looking great so far ! My poor probe has been beaten and flogged but still flys - I may have to consider a big one!

 

[EeebeeE]

It's Painting Season!!!

Here in Western NY, you can build rockets, but you have to wait for a warm day to get them painted. We had 2 60-degree days that were 3 days apart so I was able to do a lot of painting. I did the nose cone separately because nose cones have been a challenge for me. Still need to do the black and orange trim, but I think it is coming out well.

 

[Nytrunner]

That's looking real smooth.

Are you going with the stock color scheme?

 

[EeebeeE]

That's looking real smooth.

Are you going with the stock color scheme?

Close to it. The finlets will be black as will the pods at the chord edge of the fins. I have a metallic orange for the fins.

 

[EeebeeE]

Here it is next to its little brother. Still have a little brush painting to do. Struggled with the orange. It is a metallic paint and this particular brand goes on very thinly. Ended up with a couple runs, but I will sand them out and hope that the clear coat hides the flaws. Hey...as long as it looks good on the pad...right?

 

[neil_w]

Looks great. Metallics can be an adventure but put them in the sunshine and it's all worth it.

 

[EeebeeE]

Looks great. Metallics can be an adventure but put them in the sunshine and it's all worth it.

This looks more like a Candy metallic finish and it goes on like it. It looks pretty cool and I should be able to sand out a lot of the flaws. A good clear coat will hide the rest.

The bigger challenge I think is going to be the decals. I printed waterslides. There are 3. THe logo and the two wraps. The warp around the 3" airframe I was able to set up as one piece, but it is 11.25" x 7". Going to take a lot of massaging to get it to slide off. The other wrap I split in two. We'll see. They have been printed and coated. I will wait 2 days for the fixatif to completely set. Then I imagine I will swear...a lot.

 

[neil_w]

warp around the 3" airframe I was able to set up as one piece, but it is 11.25" x 7".

Why not just cut it and do it in two pieces? That sounds, "unpleasant" trying to slide off a decal that big and then also position it as a wrap.

 

[EeebeeE]

Why not just cut it and do it in two pieces? That sounds, "unpleasant" trying to slide off a decal that big and then also position it as a wrap.

It would look better as one piece. For something this large, I generally try to find a way to vent the water to the middle of the decal. Takes somr careful massage but once it is all soaked it generally just slides off like normal. Just keep everything wet, and use some dishwashing detergent so it can slide around a little. Be patient, but also be relatively fast before it starts tightening up.

 

[neil_w]

I would like to see a video of applying that one.

 

[soopirV]

I've done two large decals (full letter-sized sheet) and lived to tell about it. Not sure what paper you're using (and honestly can't remember what I have either!), but a drop of dish detergent helps wet things out a lot. Have a couple of sheets of paper towel ready, and, if you tend to get curling with your paper, maybe a hair dryer.

 

[EeebeeE]

I've done two large decals (full letter-sized sheet) and lived to tell about it. Not sure what paper you're using (and honestly can't remember what I have either!), but a drop of dish detergent helps wet things out a lot. Have a couple of sheets of paper towel ready, and, if you tend to get curling with your paper, maybe a hair dryer.

Had trouble with the large ones wrinkling before they got mounted. I think it was the Krylon Fixatif. Trying the Testors Decal Bonding Spray now, which I know doesn't have that problem. It just takes a little more time to work with so yes, I do use a little detergent to help them slide into place. Also make sure the surface area is wet as well because that reduces the number of air bubbles.

 

[dpower]

Hey, that's slick. Looks like it was a good design-build challenge too.

 

[EeebeeE]

Got the decals on. Had problems with the 3" wrap. Ended up having to do it in 5 pieces because the computer blew up the image by about 5%. So I had to cut it apart and overlap thje sections so that it would look better. Didn't get all the gaps the same size, but hey! It will look good on the pad. Here it is by itself and with its little brother.

 

[T-Rex]

Got the decals on. Had problems with the 3" wrap. Ended up having to do it in 5 pieces because the computer blew up the image by about 5%. So I had to cut it apart and overlap thje sections so that it would look better. Didn't get all the gaps the same size, but hey! It will look good on the pad. Here it is by itself and with its little brother.

Friend, that rocket looks amazing in the photos. I think you see the oopses in the decal because you know where they are. All I see is an awesome model!! Fine job, fine job indeed!!

 

[qquake2k]

I think it looks incredible!

 

[EeebeeE]

Great flight. A little challenged at NYPower since CTI motors were practically non-existent, as were 54mm ATI DMS motors. But I managed to get it up on an I445. Flew very well, very straight, and had a great landing.