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I wonder how the area density compares between 1/64" plywood and 1/32" balsa, does it change the weight or CG of the rocket much?
If I can find a decent piece (without too much searching) I'll get it and compare weights. One big difference is that the balsa would be papered, while the plywood would not. I'd be surprised if the plywood ended up weighing much different than the thicker papered balsa. Will see.
 
I'm in northern NJ. I mail order lots of stuff, but a single piece of wood like that ain't worth it.

Michael's used to carry it, but their wood rack has been in embarassing disrepair for years now (not sure why they still even have it there, honestly). HL is the most likely source, but it's a crapshoot whether they'll have a decent piece on any given day. I'll give it a decent try; if I can't find it I can use the 1/32" balsa and it'll be fine.
 
I'm in northern NJ. I mail order lots of stuff, but a single piece of wood like that ain't worth it.

Michael's used to carry it, but their wood rack has been in embarassing disrepair for years now (not sure why they still even have it there, honestly). HL is the most likely source, but it's a crapshoot whether they'll have a decent piece on any given day. I'll give it a decent try; if I can't find it I can use the 1/32" balsa and it'll be fine.

I miss the good old fashioned hobby shops. The last one in my area in Duluth, MN (my home town) closed in October. It had been open since 1947. :(
 
I miss the good old fashioned hobby shops. The last one in my area in Duluth, MN (my home town) closed in October. It had been open since 1947

Me as well. I grew up near a really good one in Grand Rapids, MI (Rider's Hobby shop, if you're ever passing through) and took it for granted that such quality well stocked hobby shops existed around the country. Now I'm on the east coast and can't find anything within at least a 2 hours radius (stopped looking beyond that).

I actually worked there growing up, so I got the employee discount. It was awesome, and a sure way to recycle my paychecks.
 
Me as well. I grew up near a really good one in Grand Rapids, MI (Rider's Hobby shop, if you're ever passing through) and took it for granted that such quality well stocked hobby shops existed around the country. Now I'm on the east coast and can't find anything within at least a 2 hours radius (stopped looking beyond that).

I actually worked there growing up, so I got the employee discount. It was awesome, and a sure way to recycle my paychecks.

The place in Duluth was Carr's Hobby. It is where I bought my first Estes rocket & motors back in high school (1966). Before it closed the end of October a friend of mine & myself made a last prilgramage to Carr's. I bought a Quest Courier.
 
The place in Duluth was Carr's Hobby. It is where I bought my first Estes rocket & motors back in high school (1966). Before it closed the end of October a friend of mine & myself made a last prilgramage to Carr's. I bought a Quest Courier.
Hobby Stop West in Toledo, OH was my place as a kid. Don't remember the kits we got there, but my dad helped his train collection there too.
 
"The hobby store" because I never knew the name. In the Princeton Shopping Center, Princeton, NJ. Long, long gone. I loved browsing and virtually never bought anything.

Where I am now I have two about an hour and a half in different directions, and a third two to two and a half in the same direction as one of them. Nothing you could call local, and I'm better off than lots of folks. Of course the one furthest away is the best of the three.

Where I lived three homes ago there is a Hobby Town USA less than an hour away in Frederick, MD, and it's got a Radio Shack parts department inside. It's new since I moved away. I still visit family in the area now and then, and it's pretty much on the way, and in the same strip mall as a really good pho shop; I've only been in once, and I'll certainly be back.
 
My local favorite was Rich's Hobbytowne in Pine Brook NJ. It was a bit of a drive so we didn't get there often, but it was two floors of hobby awesomeness. First place I ever saw Centuri rockets; they had big racks of rockets (Estes and Centuri) and I loved browsing. There's a little web page commemorating it, although sadly it lacks any pictures of the big version that I remember. Later the building became a video arcade (also pretty cool in those days), and now I don't think the building even exists anymore. :(
 
Hobby Lobby doesn't actually seem to carry 1/64" plywood at all, leaving me a bit confused where I might have last seen it. In any case, I grabbed a couple of pieces of 1/32" balsa and figured that would be fine. Unfortunately the pieces were a bit warped (there doesn't seem to be such thing as a perfect flat piece of 1/32" balsa). So I wet them down with Windex and pressed them under some weights:
Skin flattening-1.jpg
And the result:
Skin flattening-2.jpg

In other words, it did not help at all, might have even hurt a bit (hard to tell, I forgot to take this equivalent photo beforehand. No big deal, I should still be able to get it to lie flat enough on the rocket, but I was hoping for better.
 
Menard’s carries 1/64 by me. Have you tried Home Depot or Lowe’s?

I’ve laser cut it and glued it back to back for 24mm Blenders.
 
I've never seen anything like this stuff at HD or Lowe's, and we don't have Menard's on the east coast. Michael's was the one place I knew that definitely had it, but again it's been a while since they seemingly cared at all about their hobby wood sales.

The balsa will work fine, it's not worth any more search effort for the plywood.
 
I've seen it recently in one of my localish hobby shops, the one that'a a two hour drive from home, in Syracuse. Good that you're OK with the balsa this time. If you really need very thin plywood another time, shoot me a message and I'll see if I can mail you some. It'll give me an excuse to go up there.

https://www.hobbytown.com/walts-hobbytown/l15
 
So I sanded down one side of each sheet with 400 grit, both to smooth it and probably thin it just a tad as well. Then I papered each sheet with my usual label paper. Given that these pieces were 24" long, I needed three pieces of paper for each sheet. The end result is... warpy:
papered skin.jpg

I don't believe the warping will matter in the end; I'll just need to make sure I can apply some even pressure to each piece when I glue it. Each of those pieces pictured will be cut into three for a total of six to skin the body.
 
So I sanded down one side of each sheet with 400 grit, both to smooth it and probably thin it just a tad as well. Then I papered each sheet with my usual label paper. Given that these pieces were 24" long, I needed three pieces of paper for each sheet. The end result is... warpy:
View attachment 401387

I don't believe the warping will matter in the end; I'll just need to make sure I can apply some even pressure to each piece when I glue it. Each of those pieces pictured will be cut into three for a total of six to skin the body.
Kinda wondering whether straight cardstock would work. In fact, you would use a single sheet for all six sides, score it on the inside, and only have one outside seam. You'd need to have some hexagonal centering "rings" for support. Then again, I am always taking the easy way out.
 
It would probably work. I didn't do it that way for a few reasons:
1) I didn't think the cardstock would be sturdy enough, couldn't be relied upon to stay absolutely flat. I supposed I should have done a test. If I used a sufficiently heavy cardstock (like card*board*) then it would have been heavy.
2) Doing it all as one piece would have been extremely difficult. Getting all five folds in *exactly* the correct place seemed unachievable to me.
3) I'd also have needed stock at least 24" long, since I wouldn't want to have seams in the middle.

It is possible all of these could have been addressed, it just didn't seem to me like the best path to success for me so I went a different way.
 
I need six ribs on the body to support the vertices of the hexagonal skin. First, six lines are drawn down the entire length of the tube. This is when I discovered that my longest piece of aluminum angle is only about 18" long, so I needed to make each line in two sections. Usually alignment lines aren't this long.
Photo Dec 21, 4 40 06 PM.jpg
In my old test piece, I used 1/8" thick ribs, and found they were a bit thicker than necessary, requiring too much sanding. So for the real thing I'm using 3/32" ribs, about 3/16" wide. I decided pretty early on that there was no way I was going to be able to manage 24" pieces, so each rib will be made from two 12" pieces. The ribs will be hidden so the seams won't matter.

Using sandpaper wrapped around a D12 motor casing, I did a couple of passes down the underside of each piece to hollow it out just a bit, so the piece would sit down nicely on the tube. Probably wasn't necessary.

Time to glue. First I did the six pieces at the "top" of the tube, which are simpler because I don't have to worry about the fins. After applying a thin layer of TBII to a piece, I laid it down adjacent to the pencil line. It took quite a bit of care and fiddling to keep the entire length of the piece next to the pencil line, since the wood strips are quite flexible and they will quite easily "drift" until the glue is set.

Here are the first six pieces, finished. Velcro is wrapped around the end to hold down one of the ends which was wanting to lift up.
Photo Dec 21, 5 13 37 PM.jpg
They came out fine, but the fun is only beginning.

Oh, the red stripes are just a marking to help me keep track of slightly longer vs. slightly shorter pieces (an unimportant detail for purposes of this thread, but I figured someone might ask).
 
I don't believe the warping will matter in the end; I'll just need to make sure I can apply some even pressure to each piece when I glue it.

I think you're right that the warping won't matter much when it is glued down to the 3/32" ribs. But, FWIW, I've had pretty good results ironing out warps on balsa that was papered with white glue and regular bond paper. The heat effectively reactivates the PVA glue.

I forget the specifics from your test piece, but are the 3/32" ribs thin enough that the 1/32" balsa sheet will contact the body tube between the ribs?
 
The aft rib pieces are on. Every other piece is cut short to make room for the fins. The ribs around the fin slots come next.

One nice thing about this part of the build: I can be as messy as I want with the glue. All this will be hidden.
Aft ribs.jpg
 
Each fin gets a slot, tested with a fin for perfect fit:
Fin slots-1.jpg
Then a narrower rib (which only has to support one skin piece) goes on each side:
Fin slots-2.jpg
Repeat three times and all the rib gluing is done. From the back it looks like this:
Fin slots-3.jpg
Next up: trimming those rib pieces and let the sanding begin (ugh).
 
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