Semroc Scout Quick Build

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Back_at_it

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On a recent visit to ERockets I picked up a classic. I saw the Golden Scout and remembered building the Estes version back when I was a kid and had to have it. Since I don't see build thread on here for this kit I figured I'd do one. This is a small kit so this will be a quick build. Probably have a total of three hours in it so far as there was some time waiting for primers and fillers to dry.

Semroc Golden Scout. Instructions are very clear and simple to follow.

1.jpg

Below we see all of the components. A very nicely finished balsa nose cone, Main body tube, three thick balsa fins, 1/8" launch lug, engine hook and a fabric cover to go over the engine hook to hold it in place.

2.jpg

Step one of this build is straight forward. Glue the nose cone into the body tube. The body tube comes pre-marked for the fins and three vent holes are punched into the tube. To begin I lightly sanded the inside of the tube for better adhesion. Next I coated the bottom side of the nose cone with a couple of coats of TB thick and quick to give the cone a little protection from the ejection.

Next a ring of glue was spread around the inside of the tube and a little around the base of the nose cone then they were joined and held for about 60 secs for the glue to set.

3.jpg

Next was the motor hook. This runs down the outside of the tube and gets inserted into a small hole in the upper part of the body tube. When looking at the motor hook there is a short and a long end. The long end goes into the body tube. I used a couple of drops of insta-cure CA to hold the clip in place against the body temporarily.

The fabric cover was attached using BSI 15 min epoxy. Figured this would give a better bond and be easier to smooth out.

4.jpg

Below we see the hook attached and covered with fabric. Next it was time to do the fins. While the epoxy was drying I rounded the leading edge of the fins. The instructions tell you to round the outer edge as well but I chose to leave them square. One additional step was to sand a bevel into the root edge of the fin. The thickness of the material would otherwise not allow the fin to sit flush with the tube. TO do this i wrapped a piece of 240 grit around the tube then gave the root edge a couple of quick passes to get the correct contour.

The outer layer of the tube was removed where the fin attaches.

5.jpg

The fins were then attached with TBII and left to completely dry before the next one was attached. Due to the pre-marked tube and the thickness of the materials this is a very easy process.

6.jpg

I recalled that my old Estes kit came with gauze to strengthen the attachment points due to the tumble recovery. I didn't really care for the finish that the gauze leaves so I decided to go with papering the joints and the fins. I finally found a use for those IPass renewal notices that the fine state of Illinois sends out. They are printed on heavy paper so I papered the attachment points and the entire fin for a little extra strength. Once the glue was dry I coated the entire rocket in a very thin coat of finishing epoxy and let that cure over night.

At this point it is not pretty but that will change.


7.jpg
8.jpg

After letting the epoxy cure I hit the Scout with two coats of SEM high build primer and let that cure in the 100F sun we had. Next I used finishing putty to fill in any grain in the balsa and low spots on the rocket. Sanded with 240 then 400 grit.

10.jpg

Today will be a final coat of primer, a light sanding then the color coats. If all goes well I can fly this on on Saturday.
 
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looks great. Pick a nice color scheme that will be easy to find on your flying field. Rockets with no chute or streamer can be five feet away and still nearly invisible!
 
looks great. Pick a nice color scheme that will be easy to find on your flying field. Rockets with no chute or streamer can be five feet away and still nearly invisible!

Agreed. I was going to go with something obnoxious and bright but I decided to paint this one the same as the one I had as a kid.

This one is going to fly on the 1/2 A motors so hopefully we'll get it back.
 
Finally finished up the paint. Went with the same paint job I had when I build one of these as a kid. Back then I wasn't very creative and just went with the stock Estes colors.

All paints are Krylon. Gloss white on the body and fins, Banner Red on the nose cone and gloss black on one fin. If the weather holds, this one will fly tomorrow.

16.jpg
 
On a recent visit to ERockets I picked up a classic. I saw the Golden Scout and remembered building the Estes version back when I was a kid and had to have it. Since I don't see build thread on here for this kit I figured I'd do one. This is a small kit so this will be a quick build. Probably have a total of three hours in it so far as there was some time waiting for primers and fillers to dry.

Semroc Golden Scout. Instructions are very clear and simple to follow.

View attachment 523992

Below we see all of the components. A very nicely finished balsa nose cone, Main body tube, three thick balsa fins, 1/8" launch lug, engine hook and a fabric cover to go over the engine hook to hold it in place.

View attachment 523993

Step one of this build is straight forward. Glue the nose cone into the body tube. The body tube comes pre-marked for the fins and three vent holes are punched into the tube. To begin I lightly sanded the inside of the tube for better adhesion. Next I coated the bottom side of the nose cone with a couple of coats of TB thick and quick to give the cone a little protection from the ejection.

Next a ring of glue was spread around the inside of the tube and a little around the base of the nose cone then they were joined and held for about 60 secs for the glue to set.

View attachment 523994

Next was the motor hook. This runs down the outside of the tube and gets inserted into a small hole in the upper part of the body tube. When looking at the motor hook there is a short and a long end. The long end goes into the body tube. I used a couple of drops of insta-cure CA to hold the clip in place against the body temporarily.

The fabric cover was attached using BSI 15 min epoxy. Figured this would give a better bond and be easier to smooth out.

View attachment 523995

Below we see the hook attached and covered with fabric. Next it was time to do the fins. While the epoxy was drying I rounded the leading edge of the fins. The instructions tell you to round the outer edge as well but I chose to leave them square. One additional step was to sand a bevel into the root edge of the fin. The thickness of the material would otherwise not allow the fin to sit flush with the tube. TO do this i wrapped a piece of 240 grit around the tube then gave the root edge a couple of quick passes to get the correct contour.

The outer layer of the tube was removed where the fin attaches.

View attachment 523996

The fins were then attached with TBII and left to completely dry before the next one was attached. Due to the pre-marked tube and the thickness of the materials this is a very easy process.

View attachment 523997

I recalled that my old Estes kit came with gauze to strengthen the attachment points due to the tumble recovery. I didn't really care for the finish that the gauze leaves so I decided to go with papering the joints and the fins. I finally found a use for those IPass renewal notices that the fine state of Illinois sends out. They are printed on heavy paper so I papered the attachment points and the entire fin for a little extra strength. Once the glue was dry I coated the entire rocket in a very thin coat of finishing epoxy and let that cure over night.

At this point it is not pretty but that will change.


View attachment 523998
View attachment 523999

After letting the epoxy cure I hit the Scout with two coats of SEM high build primer and let that cure in the 100F sun we had. Next I used finishing putty to fill in any grain in the balsa and low spots on the rocket. Sanded with 240 then 400 grit.

View attachment 524001

Today will be a final coat of primer, a light sanding then the color coats. If all goes well I can fly this on on Saturday.
Nice rocket!

Nice cutting mat! It looks like the flexible surface used in TV science shows to explain curved space-time!
 
On a recent visit to ERockets I picked up a classic. I saw the Golden Scout and remembered building the Estes version back when I was a kid and had to have it. Since I don't see build thread on here for this kit I figured I'd do one. This is a small kit so this will be a quick build. Probably have a total of three hours in it so far as there was some time waiting for primers and fillers to dry.

Semroc Golden Scout. Instructions are very clear and simple to follow.

View attachment 523992

Below we see all of the components. A very nicely finished balsa nose cone, Main body tube, three thick balsa fins, 1/8" launch lug, engine hook and a fabric cover to go over the engine hook to hold it in place.

View attachment 523993

Step one of this build is straight forward. Glue the nose cone into the body tube. The body tube comes pre-marked for the fins and three vent holes are punched into the tube. To begin I lightly sanded the inside of the tube for better adhesion. Next I coated the bottom side of the nose cone with a couple of coats of TB thick and quick to give the cone a little protection from the ejection.

Next a ring of glue was spread around the inside of the tube and a little around the base of the nose cone then they were joined and held for about 60 secs for the glue to set.

View attachment 523994

Next was the motor hook. This runs down the outside of the tube and gets inserted into a small hole in the upper part of the body tube. When looking at the motor hook there is a short and a long end. The long end goes into the body tube. I used a couple of drops of insta-cure CA to hold the clip in place against the body temporarily.

The fabric cover was attached using BSI 15 min epoxy. Figured this would give a better bond and be easier to smooth out.

View attachment 523995

Below we see the hook attached and covered with fabric. Next it was time to do the fins. While the epoxy was drying I rounded the leading edge of the fins. The instructions tell you to round the outer edge as well but I chose to leave them square. One additional step was to sand a bevel into the root edge of the fin. The thickness of the material would otherwise not allow the fin to sit flush with the tube. TO do this i wrapped a piece of 240 grit around the tube then gave the root edge a couple of quick passes to get the correct contour.

The outer layer of the tube was removed where the fin attaches.

View attachment 523996

The fins were then attached with TBII and left to completely dry before the next one was attached. Due to the pre-marked tube and the thickness of the materials this is a very easy process.

View attachment 523997

I recalled that my old Estes kit came with gauze to strengthen the attachment points due to the tumble recovery. I didn't really care for the finish that the gauze leaves so I decided to go with papering the joints and the fins. I finally found a use for those IPass renewal notices that the fine state of Illinois sends out. They are printed on heavy paper so I papered the attachment points and the entire fin for a little extra strength. Once the glue was dry I coated the entire rocket in a very thin coat of finishing epoxy and let that cure over night.

At this point it is not pretty but that will change.


View attachment 523998
View attachment 523999

After letting the epoxy cure I hit the Scout with two coats of SEM high build primer and let that cure in the 100F sun we had. Next I used finishing putty to fill in any grain in the balsa and low spots on the rocket. Sanded with 240 then 400 grit.

View attachment 524001

Today will be a final coat of primer, a light sanding then the color coats. If all goes well I can fly this on on Saturday.
How did you get the holes to come out so nice? Mine come out rough and crummy looking. :-(.

Oh! The hole is pre-drilled! Doh!
 
Forgot to report back after the first flight. Back on 7/9/22 I got a chance to put the Scout in the air at a club launch. Flew on a 1/2A6-2. Rocket was visible the entire flight an landed about 100ft from the pad. I didn't notice it at when I recovered the rocket but I did have a very small crack where the fin meets the tube. Easy enough repair but I feel like this is one of those things that are going to happen every flight.

I really like this little rocket but I think I would like it more if I didn't need to fix it after every flight. I'm kicking around the idea of building a second one with a 13mm mini motor and more traditional streamer recovery.

07092022 S3.jpg


07092022 S4.jpg
 
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Alright it's time for part 2. I have flown my Scout three times now and all three times It has broken a fin. When built the fins were papered and they were papered to the body tube. The entire rocket was then coated in thinned epoxy before sanding and painting. At this point I'm starting to believe that broken fins are going to be the norm for this rocket so it's time to try something different.

It's time for Scout 2.0.

I ordered parts from ERockets and they arrived on Saturday. I wasted no time with getting everything prepped for a new improved Scout build. This time I'm doing a more traditional nose cone ejection with a streamer recovery. The rocket will be 13mm powered.

To get things started I laid out the parts.

- Semroc BNC-30DE nose cone. I have drilled and inserted a piece of 3/16 dowel into the base of the nose cone for a solid attachment point.
- Estes 1/8" launch lug. 1.25" long.
- Estes BT-5 body tube. 1.75" long. (should have been 1.8")
- Two Estes BT-5 / 20 centering rings.
- A piece of BT-5 body tube cut .25" long to use as a motor block.
- Semroc BT-30 tube cut to 3.75" long. Stock is 3.5" but I wanted a little extra room inside.
- 200# Kevlar for the shock cord. 18" long.
- Semroc SEM-FV-4 fins. These have been sanded to fit the contour of the body tube.

Starting at the top. The first mark on the body tube indicates where the bottom of the nose cone sites. The next mark toward the bottom shows where the top of the motor mount stops. With the added length to the body tube, moving the motor slightly rearward and shaving some shoulder off the cone I will have approx. 1.75" of free space for the recovery gear. Not a ton but it "should" work.


1.jpg

Build starts tonight and honestly this one should be really quick.
 
Started with the motor mount on this one. The motor mount is 13mm to keep length and weight down.

- Inserted the spit tube into the motor tube to act as a thrust ring. I cut it just a hair wide so it sticks out the top a small bit. No problem, it will be covered by the centering ring.

3.jpg

Next it was time for the centering rings. The body tube is BT30 which is just a hair larger than the BT20 that are so common. I didn't have BT30 centering rings but a single wrap of notebook paper around the outside of the ring made for a perfect fit. I want the motor tube to hang out the rear of the rocket 3/16 of an inch to allow additional space inside. The rear of the motor tube was marked accordingly. Yes we are looking for fractions of an inch on this build. :)

6.jpg

Next I added 18" of 200# Kevlar for the shock cord. This was tied around the motor mount below the upper ring.



7.jpg

8.jpg
After letting that dry for an hour, The motor mount was inserted into the main body tube.

9.jpg11.jpg

Will be attaching fins this evening. Should be ready for filler tomorrow.
 
Fins have been installed. I decided to try the some epoxy I bought from LOC. I've used ti on their plywood kits before but I had never used it on a balsa thin paper tube rocket and was curious on how well it would work. I like it as it's a very slow set and dry time so it really gives the material time to soak into the materials. The down side us that it takes about 4 hrs before you can handle or apply the next fin.

As you can see in the second pic. the materials soaked in to the point where can see it under the white portion of the tube and wicked up almost a 1/4" into the wood. The rocket is current primed and drying in the sun.

15.jpg16.jpg
 
Finally got some paint on this one. After sealing the nose cone with sanding sealer I hit it with two coats of SEM high build and let it sit for a couple of days to cure before sanding. The cone is ready for paint but I'm going to go back with one light coat of white primer as a base.

First color is on the main body. This has been curing for a few days so I'm ready to mask and paint the final color.

20.jpg
 
Decided to reverse the colors on this one. The tumble recovery version was white with a black fin and red nose cone so I flipped the colors but kept the red nose cone.

Just need to put the recovery system in it and call it done.

25.jpg
 
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Curious to see how this one flies! If I'm not mistaken, the original design was for the motor to propel itself up to toward the top of the rocket for stability, then drop back down for the tumble recovery. Are you adding any nose-weight to compensate for the motor being permanently attached in the aft end? Also, I apologize if I missed it, but did you run fin fillets on your first model? That may help with the cracking...... And I say all this to not detract from your craftsmanship. They both came out gorgeous looking!
 
Curious to see how this one flies! If I'm not mistaken, the original design was for the motor to propel itself up to toward the top of the rocket for stability, then drop back down for the tumble recovery. Are you adding any nose-weight to compensate for the motor being permanently attached in the aft end? Also, I apologize if I missed it, but did you run fin fillets on your first model? That may help with the cracking...... And I say all this to not detract from your craftsmanship. They both came out gorgeous looking!

You are correct that the motor moved forward for stability on the original design. On this version I have added a wooden dowel to the nose cone and it will have a small eye hook so there will be a small amount of additional weight up top. Open Rocket is showing that .20 oz. of nose weight is required to make the rocket stable so it looks like I will be adding a little more. As small and light as this rocket is currently, a little weight will help with my ability to find it :)

The original model was built with wood glue and fillets were applied to the fins. The fins were also papered and that paper was extended across the lower body tube. Once cured the entire rocket was coated in finishing epoxy which contributed to it's strength and the over all finished appearance. The fins are about as strong as I can make them without going to fiberglass. Remembering back in my youth, I had the exact same issue with the Estes Scout I built as a kid and that one even had the gauze on the fins.

I should have this one wrapped up today so I will post up the final weight and CG once completed.
 
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Back with a final update until the flight report. I've had a chance to load the rocket up and weight it ready to fly.

The first pic we have here is the empty rocket. Just the rocket with no streamer, no motor, no wadding. Total weight is .50oz.


26 Empty Rocket.jpg

Next up was two sheets of Estes Wadding crumpled loosely and a Mylar streamer that measures 1"x32". With these the total weight increased to .60oz.

More importantly, Everything fit inside the rocket which I was a little worried about. I think I actually have room for an additional sheet of wadding of move up to a 1.5" wide streamer if needed.

27 Wadding.jpg28 Streamer.jpg

Next it was time to add the motor. I friction fit an A10-3T complete with the tape. Final weight is .80oz. I will more than likely fly it on the A3-4T as the delay works better but I wanted to test with the heaviest motor option.

30 Final weight.jpg

Time to measure the CG. Completely loaded the CG is 3.25" from the tip to the nose cone. Neither the fin or the launch lug is touching anything. I went back and checked a second time after looking at the photo.

According to OR the CP is 4.239" so they are .989" apart and I'm at 1.35cal. I think the wooden dowel, eye hook and the recovery gear was enough to make up for the motor being moved rearward.

Should have a chance to fly it next weekend so I'll be back with a flight report after it flies. In the meantime, Lets build something else!

31 CG.jpg
 
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That's a pretty short kevlar shock cord. I'd personally be concerned about zipper or quicker burn-through given the stress that's going to be put on it from the ejection charge in the small space.
 
That's a pretty short kevlar shock cord. I'd personally be concerned about zipper or quicker burn-through given the stress that's going to be put on it from the ejection charge in the small space.

I was thinking that as well. I went a little conservative with length as I was worried about the amount of room I would have inside the body. Now that I know I have room, I might add a length of elastic to take up some of the shock.

I don't recall if I showed this during assembly but there is a length of heat shrink around the first 1.25" of the Kevlar just above the motor mount to shield it from some of the heat.
 
Given how light your rocket is, would it help to weigh it in grams instead of ounces?

If I needed to be that specific sure. But this rocket has good stability as the CG is well forward of the CP and the motors used will provide tons of punch off the pad so I really don't need to be that specific. Even the 1/2A3-4T is showing 58.3mph off a 48" rod and 274ft. Also, My open rocket is set to use oz. so I just like to compare apples to apples.

I can certainly switch the scale over and show the weights in grams if you guys would like to see it that way.
 
If I needed to be that specific sure. But this rocket has good stability as the CG is well forward of the CP and the motors used will provide tons of punch off the pad so I really don't need to be that specific. Even the 1/2A3-4T is showing 58.3mph off a 48" rod and 274ft. Also, My open rocket is set to use oz. so I just like to compare apples to apples.

I can certainly switch the scale over and show the weights in grams if you guys would like to see it that way.

I just noticed your weight measurements because 0.1 ounce = almost 3 grams and for a rocket that weighs less than 25 grams, you're using a system of measurement where the sigfig limitation could amount to a variation of more than 10% of the rocket weight.

That being said, no need to re-weigh your rocket just for me. You do you. :)
 
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