Sirius Mid-Power Interrogator Questions

[rosko_racer]

I bought one of these when they first came out. I have production #29... Not a bad number... After building a series of scratchbuilt and Estes LPRs I decided it was time that I built something different, from a different rocket company, and that I already had... So I pulled out the Interrogator. Parts seem to be of good quality. I checked everything and all looked OK to me.

Looks like a lot of people bought one of these but have not built it yet. Very few build threads... a couple here and I think one on YORF.

My questions are:

- Do the decals need a coat of Liquid Decal Film? Are they easy to handle?
- What was your overall experience building one?
- What would you have done differently if you had to build another one?

If you have them, please post profile pictures of your Interrogator. I prefer color pictures as references for decal placement instead of the black & white picture provided in the instructions. Thanks.

- R_R

 

[tonypv]

Raul,

I built one right after they came out and have nothing but good things to say about it.
As far as the decals go I coat all my decals with Microscale Decal Film weather I need to or not. So I can't say how they are without, but they went on fine for me with the film.
This was the first rocket that I papered the fins with self-adhesive label paper and have been doing this ever sense.
I don't think I would change anything. I did put in a longer shock cord, but I do that to every kit i build.
Has always flown great.

Here are some pictures of mine.

 

[BobH48]

I bought one of these when they first came out. It's probably one of the few rockets that I actually finished before Tony.

Like Tony, it was the first rocket that I used self-stick label paper on. If I were to do it again, I would cut a slice of paper out where the rudders attach so I could have a wood to wood joint. I have broken a rudder loose on a couple of flights and it was the paper that let go.

I didn't coat the decals with Microscale Liquid Decal Film and they are very thin. If you're careful they go on just fine. If I were going to build another, I would coat the decals.

The last two pictures show the rudders torn loose.

 

[rosko_racer]

...If I were to do it again, I would cut a slice of paper out where the rudders attach so I could have a wood to wood joint...

BobH48: Your build thread was one of the very few I found. Your suggestion was previously applied while I was building my PDR Orbital Transport. The build thread is on the archive TRF but the picture can be found here. I did it for the rudders and the ramjet sections of the OT, carefully marked the paper with a ruller and cut the sections out using a fresh and sharp hobby knife, gently peeling off the paper. The ram jets assembly and the top rudders have a strong bond to the wing. Flown it twice without incident. I am going to do the same with the Interrogator.

 

[rosko_racer]

The NC that came with my Interrogater is light blue, heavy, and of a porrous material.. lots of pin holes in it. Today I sanded it and I applied a coat of primer. The NC absorbed the paint on some places and on others it did not. Also a lot of the pin holes were not filled in by the primer... the paint kinda parted away from the pin holes...

Gentlement, how did you prepared the NC of your Interrogator for painting?

 

[tonypv]

If I remember correctly I just sanded then F-n-F, sanded and primed.
I don't remember having any problems.

 

[rosko_racer]

Thanks Tony: That is pretty much what I ended up doing today...

I wet sanded the NC first then primed it with gray Krylon primer (old formula)... when the primer dried I sanded it again until all the primer was gone and it looked like most of the holes were covered but you could still notice a lot of the bigger ones. I gave it a coat of watered down F-n-F and once dried I sanded again down to the blue. Gave it two coats of gray primer again and it looks like that did the trick of filling the pin holes. I am going to wait 2-3 days before giving it a light sanding again this time almost down to the blue then recoat but with white primer.

BTW I am done building the Interrogator. Just 24-hours for all the glue to cure then to priming and correcting any errors. I thought this would be more difficult but it only took me two days and not full time!!! The wait was for the glue to dry before going foward during certain steps.... Colors: Overall white; silver motor tail; black fin edges; black for the "internal forward end" of the ram jets and red for the "interior rear ends"; and charcoal gray for the four smaller dowels... I intend to post pictures on a separate Mid-Power Thread once I am done.

 

[rosko_racer]

... If I were to do it again, I would cut a slice of paper out where the rudders attach so I could have a wood to wood joint. I have broken a rudder loose on a couple of flights and it was the paper that let go....

.... The last two pictures show the rudders torn loose.

Ouch... that had to hurt! When I built my Estes Orbital Transport I paper laminated the fins with self-adhesive label paper and did cut out the paper were the rudders were to be glued. Since I already had practice I did the same with the Interrogator: cut out the slice of paper were the rudders were to be glued and they are rock solid on the fin now. I also cut about 5/16" of the label paper along the root from under the main wings since this part would make contact with the BT and the glue for a better joint. Will see if this technique works with this one since is mid-power.

 

[Bravo52]

Edit: I didn't use these techniques on the Sirius kits. I build them per-instructions

I had a problem with the paper de-laminating using just the self-stick lable paper. I started spraying the balsa with 3M-77 spary adhesive and that made it a little better. Once the label was on, it would pull balsa fiber off......it was stuck! But.......it was still pulling apart.

What I found out was the paint was actually causing the glue on the paper to soften........totally my fault. It seems I went to the school of "one heavy coat" of primer :blush: then mist coats to fill in. Once I started with the light coats first, I've never had a problem with de-lams.....

 

[Sirius Rocketry]

Hi,

Thought I might jump in with some answers from the Manufacturer. The decals do not have to be coated with decal film. However, some people prefer the extra thickness and durability it may give the decal, so it is more a matter of personal preference. As mentioned in the instructions, if you clear-coat your model after decal application though, it is best to do it in mist coats for the first couple of coats, because I have found that some of the nasty solvents in clear coats, if laid on too heavy, can dissolve anyone's decals. Top-coating your decals with Microscale Liquid Decal film would help in this respect as well. But it is not absolutely necessary to top-coat them, these are not Alps-made decals that scratch easily. If you are experienced with decals, I would say don't clear coat them, if you are one who has a hard time applying decals without wrinkling or tearing, the extra coat of decal film will not hurt anything.

As others have suggested here, cutting out a small strip of the laminating paper where the rudders go so you get balsa-to-balsa contact helps with the rudder-to-wing joint. Future runs of the kit will have that suggestion added to the manual. I have also used thin CA to attach the rudders to the laminated paper without cutting any paper out. The Thin CA pemetrates the paper and into the wood and makes a pretty strong joint. Then white glue fillets along the joint add extra strength.

Many good suggestions were given above for finishing the nose cone. One of my faorites not mentioned is the old-fashioned Pactra/Midwest Sanding sealer, you know, the stuff that Estes used to sell years ago and seems to keep getting harder to find because it is so hard to ship. I get jars at my local hobby shop whenever I find them. Just don't use it in an enclosed room, or you will find out why they call it "dope". I still prefer the stuff as the fastest way to fill balsa: it fills well, it dries extremely quickly, does not warp balsa, and if you want to improve the filling capabilities of it even more, just add some talcum powder to it to add some filler.

Hopefully that helps a bit!

David

 

[dcastle]

I really enjoyed this kit and have it prominently displayed in my living room next to my Interceptor. I'm hoping to get first flights on both of these soon. I used the strip removal method and it appears that the bond is very strong. I'll post some pictures soon.

Question...what in the world is that nose cone made of? I had no problems finishing it and was quite impressed with it but have never seen one like that before.

 

[dcastle]

OK, here are some pictures of my Interrogator...

 

[dcastle]

And one more...

 

[Sirius Rocketry]

I really enjoyed this kit and have it prominently displayed in my living room next to my Interceptor.... I'll post some pictures soon.

Question...what in the world is that nose cone made of? I had no problems finishing it and was quite impressed with it but have never seen one like that before.

On that particular kit, it is a microballoon-filled polyurethane cone. It was made that way to get a little extra weight up front for offsetting the larger motors, but not be as heavy as solid resin. I use the combination in some other projects and it sands quite well, and has no problem taking paint.

Nice pictures of your Interrogator build. I like the red interior of the "ramjets" and actually added red as well as black as a color to paint them in the new Interrogator G manuals. BTW, are those bases CD/DVD container bases? I have more than a few of those laying around and that is a neat use for them!

Dave

 

[dcastle]

On that particular kit, it is a microballoon-filled polyurethane cone. It was made that way to get a little extra weight up front for offsetting the larger motors, but not be as heavy as solid resin. I use the combination in some other projects and it sands quite well, and has no problem taking paint.

Nice pictures of your Interrogator build. I like the red interior of the "ramjets" and actually added red as well as black as a color to paint them in the new Interrogator G manuals. BTW, are those bases CD/DVD container bases? I have more than a few of those laying around and that is a neat use for them!

Dave

Thanks. Actually I used a flourescent orange for the tubes and black for the inside of the main intake area, though it doesn't show up well on the picture. The exposed part of the motor mount was painted silver with black in the inner part of the tube and rear centering ring. I also used filler on the joint between the wings and central dowel so that they look as much like a single folded piece as I could make them.

Yep, the stand is nothing more than a CD/DVD spindle. They make great rocket stands, the price is right and they actually look good on display, I think.