Which "Foam Board" For Fin Guides???

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TopRamen

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Lately I have been printing out the Fin Guides from Paylodbay, but I don't have any Foam Board to use. I've never had any experience at all with Foam Board and do not know what is best to use.
I've gone to Amazon, but the affordable stuff they have there is only 1/8" or 3/16" Thick. In the Pics' I have seen in some folks' Build Threads, they seem to be using stuff that looks like it is about 1/2" Thick atleast.
The 1/2" stuff on Amazon that I found only came in 40X60" Sheets and was $500-$1100. :y:
Some folks must really like Foam Board!!!:confused::confused:
I just want to buy say 6-10 15"x15" wide x 1/2" thick Sheets.
Why is this not more common.
What should I do?:confused:

Thanks for any help.
 
Oh I am sure someone here could get you some of the good stuff for half that cost. We are a tight-knit bunch though and you have to realize a "good deal" has to be completed low key, cash only, no witnesses etc. Once you start buying off grid, you will be indebted to the risk takers and be expected to be a loyal customer. If you aren't ready to play with the big guys you can always go to Michaels or Hobby Lobby and fork over $2.99.
 
Dollar Store stuff (about 1/4") for...well, a dollar. When I use fin guides (not too often). I also make them from the top of pizza boxes.
 
Dollar Store stuff (about 1/4") for...well, a dollar. When I use fin guides (not too often). I also make them from the top of pizza boxes.

Dangit! There goes another lucrative income stream! How rude! I was gonna post about having a stock of repurposed light weight sound insulator panels from the astronauts' sleeping quarters on the ISS, but noo-you gotta go a blab they can get it at the dollar store. Hey- why didn't NASA think about that??
 
I would use 1/8" or 3/16" foam board on LPR, and 3/16" or 1/4" foam board on MPR. Not really based on impulse, but more based on the OD of the airframe as well as the span of the fins.

I use two for fin placement, one for the forward portion of the fins the other for the aft portion.

Typically I get mine at Hobby Lobby and is usually just a few bucks. Michael's probably carries them as well.

Greg
 
One thing about using foamboard products is warpage.

If you want a seriously 'straight and proper' fin aligner, then you'd likely be better off with the thicker 1/2" stuff, which I have seen at Michaels, HobbyLobby, and sometimes even Walmart. The cheap Adams Readiboard (the dollar-a-sheet stuff mentioned) does warp badly over time, and may throw off your fin guide as a result.

A 20x30 sheet of the 1/2" stuff is like $6 or so. That's likely your best bet.
 
Thanks for the Replies.
I was hoping to find it online, since we don't have Hobby Lobby or Michaels or anything in my State.
We do have a Walmart, so I'll try there first.
I found this 1/2" stuff online at places like Uline, but you have to order a whole "Carton" which is a couple hundred bucks.
Yes, I "Googled" and all that fun stuff.
I'm going to Walmart on Saturday, so I'll see what they have there then.
I always get a lot of helpful suggestions here of where to go to buy stuff, but Folks don't take into account that I live in Vermont, where there is NOTHING.:( That's why I like to just order Rocket Stuff online.
If I can't find it at Walmart, I'll just order the 3/16" stuff and glue a couple sheets together.
I don't NEED it, but it would be nice to have as a Tool, since it seems to work so well for others.
 
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Check the school supply isle for 'project/display boards'. local sign companies may also have 'gator board'. Hate your local politician? Repurpose his yard art.
Heck if you keep drawing blanks pm me and I'll send ya a coupla chunks as long as your fin span is less than a foot diameter.
 
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As mentioned before, the foam boards from a "dollar" store work great and are inexpensive. I buy them at a local Dollar Tree store.

-- Roger
 
I can't imagine using thick stuff. You'd have to cut the slots absolutely straight 90 degrees to the surface to keep it from twisting the fins or having them crooked to the tube. The purpose is to keep them the right distance apart, and thin stuff works just fine for that.
 
If you wish a extremely 'straight and proper' fin aligner, For foam board then you would possible be more happy with the thick 1 by 2" size, that I actually have seen at archangel, typically even Wall chart. A budget Adams bread board will warp poorly over time, and should throw off your fin guide as a result.
 
I've been having good results using the stuff I get at Dollar General. Since I started this Thread I've probably baught about 10-12 Sheets of it.
I've even made a Glider from it, but that is still a work in progress to some degree, and on the back burner for now.
Rex, do you mean Centering Rings for a Motor Mount? I've never considered that before. How would the foam hold up to the heat?
I suppose you could use a layer of Fiberglass on each side too to enhance them and still be pretty lightweight.
 
On my commercial builds, I'm planning on using dollar store foam for 2 of the 3 centering rings (They're non flying advertisement pieces). The upper ones will be foam, the bottom one will be aircraft ply. As I'm epoxying the fins to the motor tube (for strength/alignment), I know that I can get away with that. I've thought about foam CR for an actual flying model, but I'm a little iffy on how well the upper ones would handle the flames and heat of the ejection (e.g. burst into flame, and destroy the rocket), A workaround I thought of was to install a standard wooden CR to a stuffer tube, and thus the foam would be protected from direct flame, hot gasses, and burning particles.
 
Try Target,,,
I got a foam board with white paper laminated to it that I use as a background to take pictures of my harnesses for my site...
I don't remember exactly how much it was but it was very inexpensive..
It would be perfect to make a fin template out of...

I get very large heavy weight cardboard sheets from Home Depot or Lowes to make fin templates...
You can pick up a cheap can of spray adhesive to glue the printed sheet fin guide down with..

Teddy
 
to date my experiments with foam core centering rings are limited, however I haven't seen any problems, yet. for my bt60 'Depron(tm) flyer'(24mm mount) I glued cardstock to the 3mm foam(white glue), then coated the exposed surfaces of the rings with some white glue(the fins are foam core as well but w/o the outside coating of glue). my mostly harmless rocket(29mm mount, ttw balsa fins), I used 1/4" foam core with a white glue coating for the rings(note the glue also makes it possible to paint them w/o turning them to goo :)). white and yellow glue makes a nice protective layer, it does suffer from erosion when used on a blast deflector for ap motors though.
Rex
 
We do have a Walmart, so I'll try there first.


Just bought a 2-pack of ¼″ 24″×48″ foam core there last night. don't remember the exact price, but no more than a few dollars.
Also, remember that WalMart has a much larger selection online with free ship-to-store for most products.
 
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