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Bruiser

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I haven't done "regular" glassing so I can't really say. I have watched videos though and I think it will come down to how much sanding is involved. The "regular" glassing videos I have watched all seem to use peel ply and there seems to be little sanding involved. I haven't gotten to the sanding yet on this process so I don't know how bad it will be. I suspect that this process will be lighter because one leg from the nylon weighs nothing.

The resin seems to be setting up well. I am excited for what I find in the morning.

-Bob
 

Bruiser

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I dry sanded the body tube with 120 3M paper. It took a good 20-25 minutes and produced a lot of dust. It came out pretty smooth but you could see some areas the sandpaper did not touch. Kinda like dimples on a golf ball. That is why you do a second coat which I applied during lunch. It took about a quarter of the epoxy the first coat took. It was quite a challenge to turn the body tube with one hand and scrap the excess epoxy off using a playing card with the other hand. Oh, the body tube was slid over a broom handle. It came out looking very even and I think it will take minimal sanding to smooth it out. I'll see in the morning.

Now I have to decide what to do about the fins. I think I will coat them with finishing resin as well. It'll probably take two coats. I imagine the first coat will get soaked up by the wood so I think a second coat will be needed before I can sand. That means I am looking at four days before I can sand them and glue them to the body tube. Good thing I have been secretly working on another project (cue Dr. Evil laugh) ba-ha-ha, ba-ha-ha!

-Bob
 

Bruiser

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The final coat was good. Nice and even, took minimal sanding to smooth it out. I wet sanded it making a few passes with 220 first then a few with 400. It's amazing how you can feel the difference in your fingertips when it goes smooth. That's going to be it for this process on the body tube. Now it gets back on track with the normal process of filler primer and what-not. I've attached a pic: you can't really see the smooth but we love pictures :)

Cuda Final Coat Sand.jpg


The next thing I want to do is coat the fins but my furnace was replaced yesterday and the new one is not working. Turns out they brought out a "new" unit from their warehouse but they had cannibalized some parts from it at sometime in the past. Of course they didn't know this until it would start. That when they discovered it was missing some switches inside the furnace... Anyway, it needs to be warmer in here for the resin to work well. Hopefully they will get here today promised. Preferably sooner than later :)

-Bob
 

Bruiser

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Well I have been working on the fins but there's not much to show for all the sanding. I am deciding on what trick I am going to use to "accent" the "peaks" on the fins this time. It'll be with primer I think, just need to figure out which technique.

I also finished cutting out the slots for the fin tabs.

I have been working on the conduit and it's ready to glue on. Can't decide which glue to use. The conduit is balsa and it is going on sanded finishing resin. I am inclined to use some medium CA followed by a small fillet of Titebond Quick and Thick. What do you think?

Cuda Conduit Taped.jpg


-Bob
 

neil_w

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Well I have been working on the fins but there's not much to show for all the sanding. I am deciding on what trick I am going to use to "accent" the "peaks" on the fins this time. It'll be with primer I think, just need to figure out which technique.

I also finished cutting out the slots for the fin tabs.

I have been working on the conduit and it's ready to glue on. Can't decide which glue to use. The conduit is balsa and it is going on sanded finishing resin. I am inclined to use some medium CA followed by a small fillet of Titebond Quick and Thick. What do you think?

View attachment 449301

-Bob
I'm doubtful the Q&T will bond with the resin. Epoxy would seem like a good choice here, if you can rough up the tube that'll go under the conduit.

As for fillets... @BSNW 's construction adhesive looks enticing here.
 

Bruiser

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Thanks Neil,

Titebond Quick & Thick Multi-Surface Glue is the thickest, fastest-drying water-based glue available for use with porous and semi-porous materials. It is ideal for wood, pottery, ceramic, stone, glass, fabrics, leather and most craft-type materials.

It says porous and semi-porous materials... Does ceramic or glass fit in those categories? Anyways, seems like quite a variety of materials

I was thinking of using it because it is easy to work with. Apply it, wipe with a wet finger and wha-la, nice fillet but epoxy is probably better for this. I've never used epoxy for fillets before. I know you can wipe it down with alcohol to smooth it but how do you initially spread it? That conduit is only 1/8th inch tall. Maybe tape on the body tube and on top of the conduit then apply with a stick quickly then smooth with a wet gloved finger, then quickly pull the tape off and smooth out one more time?

-Bob
 

neil_w

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Sorry I can't give advice on epoxy fillets, never having done them. But now that I think about it, for that piece, it seems that the fillets will be cosmetic only, so you could really use *anything*. Q&T, or even wood filler or spackle or who knows what. It probably doesn't matter if the piece is well-glued to the body, given how thick it is.
 

Doug Rocket

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For Epoxy Fillets, you can mix up your epoxy and add Micro-Balloons to thicken it up so it won't be so runny or some type of epoxy filler (Colloidal Silica Adhesive Filler). Use painters tape to tape off the area (body tube and fin/conduit) where the fillet will go then apply epoxy. Use a round Wooden dowel to create the nice radius for the fillet.
 

Doug Rocket

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Been following your build...I'm building a 4inch Madcow Patriot for my level 2 and building similar boattail for the rocket, but trying out a 3D printed part.
 

Bruiser

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Hey Doug,

Thanks for following and for the info on epoxy fillets. I'll be using epoxy on these fins. I'm not too worried about the rear fins as they are ttw and they attach to the motor mount. The front are sorta ttw as they don't attach to anything but the body tube so I feel I need a strong glue like epoxy.

So far the only printed part I have experience with was the nose cone on a Rocketarium Black Brant. I'm thinking of buying a few pieces for a Doorknob build.

-Bob
 

Bruiser

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I have some micro balloons. The seem to last forever :)
Micro Balloons.jpg



I just used them over this past weekend. I was working on the Cuda fins and I wanted to accentuate the changing "facets" on the fins so I laid down a piece of tape at the "panel line" then brushed on some primer thickened with micro balloons up to the tape. After the primer dried I made a few wet sanding passes with 220 until the edge of the tape was exposed then I pulled the tape. A few wet passes with some 400 took the "sharpness" out of the ridge. When I do a full prime the paint should flow over the ridge and show the angle change well. They are ready to be glued to the body tube now. I thought I'd get them glued on this week but it's been a busy week.
Cuda Fins Primer Lines.jpg


-Bob
 

hobie1dog

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I am enjoying your build process, thank you for all the pictures. It sure looks like all of that work with filling spirals, and glassing etc. it would have been so much easier just to get a piece of fiberglass tube which would be really smooth, no spirals, and structurally very strong.
 

Bruiser

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so much easier just to get a piece of fiberglass tube

Yeah, but where's the fun in that :) You can buy a lot of stuff that helps decrease the work you have to do like ordering custom fins from a laser cutter but I like cutting mine out on the bandsaw. Same for centering rings. You buy a tube you can't really "own" the smoothness like I can with this project :)

So today the fins went on. I still need to do fillets but that'll be next week. Sometimes I get in a rush and get upset if progress is slow. I need to remind myself this is a hobby, a stress-reliever, not a job.
Cuda Fins Tacked.jpg


-Bob
 

Ez2cDave

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Yeah, but where's the fun in that :) You can buy a lot of stuff that helps decrease the work you have to do like ordering custom fins from a laser cutter but I like cutting mine out on the bandsaw. Same for centering rings. You buy a tube you can't really "own" the smoothness like I can with this project :)

-Bob
That is why it's called "scratch-building" and not "assembling" . . . There is a lot of personal satisfaction in the approach Bob is taking !

Dave F.
 

Bruiser

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I finally got back on the Cuda to do a little work. After applying what seemed like a roll of tape I did the epoxy fillets on all eight fins. THey are drying now and you really can't see anything but I did take a picture of the tape job.
Cuda Fins For Epoxy.jpg


So the process was tape, which I think I hate more than sanding because when you sand you are making progress. When you tape it's just preparation for something that is progress like making fillets or getting paint on. Oh, then mix up the epoxy and add a little micro balloons to keep it a little lighter and they will help making sanding easier if I have to sand. Then apply the mix and smooth out with a rubber glove tipped finger. Remove the tape and smooth one more time with the gloved finger wet with some alcohol. Walla, then wait to spray some primer and see how well you did :)

-Bob
 

Bruiser

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Added some fin rotary actuators today.
Cuda Spin Motors.jpg


I'm thinking I might get to spray the first coat of primer on today. Something is saying that I need to do something else first but I don't know what. I did remember to cut the nylon from the holes for the rail buttons. I've got a few hours to remember before it go/no go time :)

-Bob
 

Bruiser

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I did spray the primer and overall the outcome was good. I didn't have any problem caused by the quasi glass process and the body tube looks very smooth. I did have some areas that need some work, but I expected that.

Here are a coupe of spin motors after primed. They needed a little filling so I used some CWF.
Cuda Spin Motors Filled.jpg


After sanding
Cuda Spin Motors Sanded.jpg



One of the fillets on a forward fin was bumpy so a little cwf on it
Cuda Fin Filled.jpg


and sanded
Cuda Fin Sanded.jpg



Ready for another coat of primer.

Just few minutes ago I did remember what I had thought about doing before I shot primer on. I was going to use some chart tape to simulate where sections of the rocket joins. The process is to apply the tape, lay on a couple coats of primer then remove the tape. It creates a "break" in the surface to simulate the joint. Might still do it before the next coat of primer.

-Bob
 

Bruiser

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I gave her a good coat of primer and let it sit over the weekend
Cuda Body Primer.jpg



I gave it a light sanding today then applied 1/64th chart tape where there are panel seams and sprayed some primer. I want to get on one more coat on before I pull the tape off but I need more primer...
Cuda Panel Line Tape.jpg


Cheers,
-Bob
 

Bruiser

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I lightly sanded the taped areas. Just enough so I could see the black on the tape then I pulled the tape off and gave them another very light sand. I just want to get rid of sharp ridges without really sanding the primer build up down any. They look good to me but the final proof will be after the color coat goes on
Cuda Panel Lines Sanded.jpg



I have been obsessing over the screws. Should I paint them on??? Should I make decals??? Should I make vinyl decals??? What color should they be??? What type of head??? Should I try to make a tool to emboss them in??? Will that work??? Will I need to burn them in??? So many questions...

I decided to try making an embossing tool. I took a phillips screwdriver and ground the point off. Then I ground down the shank of the screwdriver so I could slide a piece of 3/16th brass tube over it. I sanded the tube down to be even with the + on the screwdriver then tried pushing it into some card stock. The results were inconsistent. I tried "dressing" the end of the tool in different ways but I kept getting inconsistent results.

I decided to up the ante and heat the tool up to try burning the screw heads in. I heated the tool with a propane torch and tried it on some card stock and the results were better. After getting in some practice I made some placement guides from paper and went to town on the model. One thing I noticed right away was that it acted differently (smoked) on the model than it did on the cardstock I think due to the laminating resin/nylon covering. After 64 burns I was done. Here are the results and I included the tool in the pic
Cuda Screws Burned.jpg



So now the screw heads were a little "lifted" above the surface. I did a light sanding on them and that helped a lot with consistency. I did have a few screw heads come out a little deformed but it a good "one-footer" :)
Cuda Screws Sanded.jpg



Again, just like with the panel lines the proof of concept will be the color coat once I get that sprayed on. The can of Krylon Industrial Acryli-Quik Cuda Missile Gray is standing by :)

-Bob
 

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I want to get on one more coat on before I pull the tape off but I need more primer...
Good Afternoon Bob;

Impressive build with great attention to detail!

Regarding primer, if it was mentioned in the thread I missed it. What are you using? It used to be that THE primer of choise for the control-line stunt community (who still build all their models if you want appearance points at the AMA Nationals in the "Open" category) was NAPA DC540, and I used it on my rocketry builds as well. The formula changed the other year and the new DC540 is a far cry from what it once was. Last time I visited the forum a few months back, the search continued for a replacement.

Thanks in advance,
Dave
 

Bruiser

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Thank you for the kind words Neil and David

The primer I am using is Rustoleum 2in1 Filler & Sandable that I bought at WalMart in the automotive section. This is the first time I have used it. The coverage is good and it sands well.

I was using the Rustoleum Filler Primer and it worked well for me too. Good coverage, sanded easily, could paint over with Rustoleum 2X paints and Duplicolor perfect match lacquers.

I read the 2in1 is the same as the filler primer but the can is slightly larger so I thought I would try it. So far it seems the same. We'll see when I spray the color on. I am using the Krylon Industrial Acryli-Quik paints for the first time on this build. They are lacquer paints like the Duplicolor paint but are available in non-metallic colors. I read about them on TRF. They are hard to come by and cost about twice as much as a can of 2X but if they are as good as reported they will be worth it.

-Bob
 

neil_w

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I am using the Krylon Industrial Acryli-Quik paints for the first time on this build. They are lacquer paints like the Duplicolor paint but are available in non-metallic colors. I read about them on TRF. They are hard to come by and cost about twice as much as a can of 2X but if they are as good as reported they will be worth it.
They sound great. Did you find a place to purchase them locally, or did you have to mail order? I'd much prefer to buy spray paint from a store if possible, but I haven't found it anywhere yet.
 

Bruiser

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I found that Grainger carries them but not my local store which is actually 90 miles away. If I order them online the store will have them in 1 to 2 days. I go to El Paso now and then to take my dog to his handler so I try to time the ordering to coincide with a dog trip. They will ship them though. It was going to be 10 bucks to have 2 cans shipped to the house...

I sprayed on the Cuda Missile Gray (also known as Pewter Gray) and it went very well. Coverage was good and it "flashed" pretty quickly so there were no runs. It's not real glossy, more of a semi-gloss. Normally I would spray a wet coat to get a nice gloss finish but the can instructions specifically said no heavy coats. I'll have to check the can of clear to see if it has the same warning. Here's the picture...
Cuda Screws Painted.jpg



I was planning to paint the screws good to simulate a plated screw but I am kinda happy with the way they look now. They look to good to risk messing them up trying to make them better :)
SCREW.JPG


-Bob
 

cobra1336

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I found that Grainger carries them but not my local store which is actually 90 miles away. If I order them online the store will have them in 1 to 2 days. I go to El Paso now and then to take my dog to his handler so I try to time the ordering to coincide with a dog trip. They will ship them though. It was going to be 10 bucks to have 2 cans shipped to the house...

I sprayed on the Cuda Missile Gray (also known as Pewter Gray) and it went very well. Coverage was good and it "flashed" pretty quickly so there were no runs. It's not real glossy, more of a semi-gloss. Normally I would spray a wet coat to get a nice gloss finish but the can instructions specifically said no heavy coats. I'll have to check the can of clear to see if it has the same warning. Here's the picture...
View attachment 452386


I was planning to paint the screws good to simulate a plated screw but I am kinda happy with the way they look now. They look to good to risk messing them up trying to make them better :)
View attachment 452387

-Bob
Use a fine gold sharpie
 

Bruiser

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I was thinking about a Sharpie. I am thinking of another area for a black Sharpie also.

Today I painted the fins with Model Master Cuda Fin Metallic Aluminum (also known as Diamond Dust). I was concerned that I didn't overlap the gray high enough on the fillet and sure enough I did not on two of the fins. I will touch those areas up over the weekend. I also need to "work" on the fin paint some to make it look more realistic. Just a little too "sparkly" right now and they need a little "grain".
Cuda Fin Paint.jpg


-Bob
 

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