LOC Comet - Custom project for LDRS 37

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Because the fins are very pointy and long, I decided I wanted to try fiberglassing them. Honestly, I'm not sure how well I ended up protecting the very pointiest parts, as you will see, but the process was interesting because I had never done it before.

I got all the laminating supplies from a local shop that sells this stuff, mostly to local manufacturers and people who build aircraft. They were not at all customer friendly and not about to give any kind of advice for fear of liability issues, but they did have the things I needed, and I had waited too long to be ordering things online.

I began by cutting out pieces of the 5.7 oz glass to match the fin size.

Comet-Build - 1.jpg

I also cut out pieces of the other materials. Below in the front is the perforated release film that lets excess laminating epoxy escape and is easy to peel from the cured laminated surface. Next is the breather cloth that absorbs the excess epoxy. And in back is the Foodsaver bag material I used for vacuum bagging. I got a Foodsaver from a local thrift store for $5.99. A roll of the bagging material cost more than the Foodsaver itself!


Comet-Build - 5.jpg

I wetted out the wood with laminating epoxy, laid the glass cloth on top, and wetted it out a bit more.

Comet-Build - 7.jpg

Put a piece of release film over the wetted parts.

Comet-Build - 8.jpg

Put a piece of breather cloth on top of that.

Comet-Build - 9.jpg

Once both sides are done as above, slide the whole sandwich into the Foodsaver bag, turn on the vacuum and seal it.

Comet-Build - 10.jpg
 
Overnight, the epoxy cured on all the fins.

View attachment 345848

I removed the disposable parts -- vacuum bag, breather cloth, and release film. These are the fins laminated to the glass cloth.

View attachment 345842

I cut the fins out of the excess cloth. Scissors did not work well but a box cutter and xacto knife worked fine.

View attachment 345843

There were some flaws. You can see a bristle from the chip brush in this shot and a few wrinkles near the fin tab. You can also see the the release film left little bumps where the perforations were.

View attachment 345844

There tended to be wrinkles along the curved edge of the fin.

View attachment 345845

The main thing I was not crazy about was that the lamination did not wrap well around the edges of the fin, which is what I really wanted to reinforce the most. But there was no time to do anything about it. I figure the resin alone probably penetrated and strengthened the wood some, and the fiberglass makes the entire fin stiffer. But it wasn't the perfect solution for the vulnerable edges and points that I wanted.

View attachment 345846

I sanded down the worst of the bumps and wrinkles and sanded the non-adhered glass cloth from the edges. I didn't worry about making it perfect and planned to take care of the rest during the finishing steps with filler primer, glazing putty, and paint.

View attachment 345847
 
Sometimes I was working on multiple part of the rocket at the same time, waiting for one part to cure, while working on something else. So while the fins were curing, I worked on prepping the motor mount tube and other parts of the fin can assembly.

This always disturbs me, but I peeled the nice, pristine glassine off the motor tube in order to get good epoxy adhesion.

View attachment 345849

I roughed up the plastic inside the boat tail cone where the internal fillet will be, also for epoxy adhesion.

View attachment 345850

The boat tail comes with a nice smooth surface, that nothing will stick to.

View attachment 345851

How many pictures do you see in this post? Three? Meet too. For some reason the forum software things there are 10 and it won't allow me to upload the rest for this step, so see you in the next post!
 
How many pictures do you see in this post? Three? Meet too. For some reason the forum software things there are 10 and it won't allow me to upload the rest for this step, so see you in the next post!

Actually, this post and the post before don't show any pics for me. Just Attachment 345849 or so on.
They're blue like a link, but when I click on them it tells me I'm not authorized... :(
 
Actually, this post and the post before don't show any pics for me. Just Attachment 345849 or so on.
They're blue like a link, but when I click on them it tells me I'm not authorized... :(

Hmm... I'n not sure what is happening. As I was uploading the images, I was seeing them just fine. During the last post, the system told me I could not upload more than 10 pictures in a post, even though I had only uploaded 3. I refreshed the page, and now all I see is the blue links in the earlier posts too... This forum is built on crap software, and it can make it very hard to be a contributing member sometimes!
 
Actually, this post and the post before don't show any pics for me. Just Attachment 345849 or so on.
They're blue like a link, but when I click on them it tells me I'm not authorized... :(

Hmm... I'n not sure what is happening. As I was uploading the images, I was seeing them just fine. During the last post, the system told me I could not upload more than 10 pictures in a post, even though I had only uploaded 3. I refreshed the page, and now all I see is the blue links in the earlier posts too... This forum is built on crap software, and it can make it very hard to be a contributing member sometimes!

I'm going to try it again...

Comet-Build - 72.jpg

Edit: OK that looks like it worked. If the entire system comes crashing down, at least we have an almost final pic uploaded.
 
Hmm... I'n not sure what is happening. As I was uploading the images, I was seeing them just fine. During the last post, the system told me I could not upload more than 10 pictures in a post, even though I had only uploaded 3. I refreshed the page, and now all I see is the blue links in the earlier posts too... This forum is built on crap software, and it can make it very hard to be a contributing member sometimes!

I'm going to try it again...

View attachment 345853

I see it!!!
 
The image uploading tool is being flakey, so I’m not wasting my time fighting it just to have the images replaced with these attachment links. Sorry! Maybe when they fix it...
 
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