Help Me Fix My L1 Disaster

[beeblebrox]

The fins are already strong, so you only need to spruce it up. the cheapest solution by far: Sherwyn Williams Paintable Caulk....This is great stuff, I used it as a painting contractor for years. Use what is left to fix up windows outside, bathroom (Not the tub) Cracks in walls...yes, don't use spackle, caulk is flexible so you wont get re-cracking... Your $500 tip for the day. lol

 

[Pariah Zero]

I’ll second the ‘body filler & sand’ method.

Pics are after and before primer.

 

[thequick]

Third on the body filler method. Leave the epoxy alone and just lay some nice fillets with a bigger radius on top of the existing glue.

 

[ksaves2]

Sheeoooot! Les they don’t look “that” bad. Just repaint it, go fly the rocket and save the artsy fartsy fillets for the next project! Oh BTW the square leading and trailing fins is a good idea for ”draggy” fins on an L1 rocket as it will likely help a bit to keep the apogee lower and hence increase ones chances of getting their rocket back for a successful cert. Only thing I recommend to folks is sim the flight like crazy so the proper motor delay can be chosen to avoid a zipper of a cardboard tube. I see you’ve chosen electronic deployment so that eliminates that headache. Kurt

 

[BABAR]

Sand off any paint and primer to get to firm attachment surface.

Do big fillets with micro balloons or whatever filler (with gloves and appropriate protection), just big enough to cover the defects.

Prime and paint

Recheck CG (big epoxy fillets may add weight, you may need to add nose weight if significant shift)

Fly and enjoy!

 

[lowga]

Embraced the suggestion that I should do some touch-ups, repaint and make peace with my first high power model. Tried the suggestion to use Sherwin Williams Paintable Caulk to dress up the fillets but results were poor.

It turns out my original fillets are much wider than they may appear in the photos. Even cutting the tube for the widest possible band of caulk, it takes too passes to cover them. Smoothing them out using fondant tools, rubbing alcohol, etc. still didn't yield good results.

Thinking about trying body filler and sanding instead--but have zero experience with body filler. Is there a good thread or video tutorial before I attempt it?

 

[Mike Helm]

Just fly that funky rocket and save your effort and ambition for the next one.

 

[John Kemker]

"Fly that funky rocket, fly boy!
Fly that funky rocket, right!
Fly that funky rocket, fly boy!
Lay down that caulk gun and fly that funky rocket till you die!"

 

[ChicagoDave]

Steve what are some of the signs of getting sensitized to epoxy? I need to be more carefull?

I found West Systems has a great resource on Epoxy safety. They discuss the methods and risks of exposure as well as recommendations to limit the risk of sensitivity. Even if you don't use West Systems specifically I highly recommend reviewing the information they provide to limit your risks.

Symptoms range from mild irritation to poison-ivy like rashes to life-threatening anaphylaxis (in rare cases).

https://epoxyworks.com/wp-content/uploads/2015/11/000-574-Epoxy-Safety.pdf

My girlfriend developed a server reaction to Nickle out of the blue and ended up in the emergency room with anaphylaxis. Talk about scary - not knowing what was causing her life-threatening reaction! Once she got diagnosed it was much easier for her to avoid exposure. Anyway the point is if you get sensitized you're stuck with it as long as you have your body so it's way better to avoid the problem in the first place.

 

[Pariah Zero]

There are two kinds of body filler: one-part, and two-part.

The two-part is typically catalyzed polyester filler. Smells like hell’s dumpster, cures pretty fast. I’ve had good results with Evercoat Rage Optex - it changes color from pink to green as it cures. Easy to sand. Some fillers can become pretty difficult to sand if left overnight (Bondo brand comes to mind). You get what you pay for, and I’d rather work hard at my “real job” and sweat less for my hobby.

The other type is a one-part putty: toluene evaporates, and it dries. It’s best for very thin layers, and is best if left to dry overnight before sanding.

I also used Clean Sheetsfor a mixing board. https://smile.amazon.com/dp/B00AZA1XVK/ref=cm_sw_r_cp_api_i_FzuyFbMK5RK25 It came with a spreader that has a rounded edge that was pretty perfect for my 1” radius fillets. It’s also a good size because you don’t want to mix too much at once.

I’ll also note that Dura-block makes a 1” round sanding block. It was ok, but slow. I ended up using a Harbor Freight 2” random orbital sander (compressed air powered), and 180 grit discs. It seems kind of counter intuitive, but it actually made the joints beautifully smooth and rounded. It did, however, use air like crazy...

 

[cbrarick]

Cram a warp-9 in there and no one will see the fillets.

 

[Donnager]

There are two kinds of body filler: one-part, and two-part.

The most common is the red glazing putty made by Bondo, but is just a single part.

My favorite, if you can find it, is 3M Acryl-green spot putty, which is also single part. You may have to go to a good parts house or an automotive paint shop. It dries faster than the bondo version and is very sandable. The best part is you can buy a pretty large tube (compared to bondo).

 

[o1d_dude]

The 3M spot putty is the real deal

Haven’t been able to find it for a while, though.

Still looking.

 

[_kestrel_]

https://www.amazon.com/3M-05096-Acr...rds=3m+acryl+green&qid=1600717404&sr=8-1&th=1
I hadn’t heard of this before. I’ve been using the red Bondo spot putty but am willing to give this a shot.

 

[Pariah Zero]

https://www.amazon.com/3M-05096-Acr...rds=3m+acryl+green&qid=1600717404&sr=8-1&th=1
I hadn’t heard of this before. I’ve been using the red Bondo spot putty but am willing to give this a shot.

I also bought a tube of green Acryl from Amazon. My only advice for it I’ve already said: unless you’re filling pinholes, give it at least 12 hours to dry.

I tried some fillet work with it (instead of using 2-part Evercoat Optex). Even at 38°C (100°F) in dry desert, a thin coat (about 1mm), was still soft after six hours.