Basswood for hpr fins

[Lt72884]

Amazon seems to have a decent deal right now on 3mm basswood sheets. I have a laser cutter. I have never used basswood so i am curious to know if it will work for hpr fins? I know it works for model rockets, but curious as to level 1 and 2 rockets? I used aerofin sim lite to see at what speed fin flutter and divergance would happen and it seems it can handle pretty decent speeds.

Anyone have experience with basswood fins?

Thanks

 

[David Schwantz]

I would not use basswood for HPR. Ply at the very least.

 

[rharshberger]

I would not use basswood for HPR. Ply at the very least.

I concur, it can be done, I have seen L1 cert rockets with Basswood fins, a lot of the survivability of that material in HPR has to do with the fins shape and its resistance to flutter....if it flutters much....well its confetti time...

 

[lakeroadster]

Amazon seems to have a decent deal right now on 3mm basswood sheets. I have a laser cutter. I have never used basswood so i am curious to know if it will work for hpr fins? I know it works for model rockets, but curious as to level 1 and 2 rockets? I used aerofin sim lite to see at what speed fin flutter and divergance would happen and it seems it can handle pretty decent speeds.

Anyone have experience with basswood fins?

Thanks

What one man can do, another can do..... have you considered making your own basswood ply?

My L1 cert rocket (which has not flown yet) is a scratch build and I made my own basswood ply using (2) pieces of 1/8" basswood, which I glued with Gorilla Glue and clamped between boards until the glue cured.

Just depends on how much of the build you want to do yourself.

​

 

[mbeels]

More than the size of the motor, I think it largely depends on the maximum expected flight speed and fin geometry. I've flown an H54 in a rocket with papered balsa fins. It was a light weight and large diameter very draggy rocket (Plasma Dart II XL) so maximum speed was relatively low. But I bet a G80 would be capable of shredding fins if they were too floppy. So it depends....

 

[BigMacDaddy]

Amazon seems to have a decent deal right now on 3mm basswood sheets. I have a laser cutter. I have never used basswood so i am curious to know if it will work for hpr fins? I know it works for model rockets, but curious as to level 1 and 2 rockets? I used aerofin sim lite to see at what speed fin flutter and divergance would happen and it seems it can handle pretty decent speeds.

Anyone have experience with basswood fins?

Thanks

Are you sure it is not plywood? Lots of stuff listed as "Basswood" is actually birch plywood.

 

[Lt72884]

What one man can do, another can do..... have you considered making your own basswood ply?

My L1 cert rocket (which has not flown yet) is a scratch build and I made my own basswood ply using (2) pieces of 1/8" basswood, which I glued with Gorilla Glue and clamped between boards until the glue cured.

Just depends on how much of the build you want to do yourself.

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I have thought of this. What has stopped me is my laser cutter wattage (5.5), So im guessing quarter inch basswood fins are going to be better than the 1/8th inch, but heavier. My laser cutter can handle 1/4th inch but it does struggle. It has air assist etc.
What about making my own 4mm ply doing the same technique? I will have to finsim the shape i want to use and compare it to open rocekt sims.

thanks

 

[Lt72884]

Are you sure it is not plywood? Lots of stuff listed as "Basswood" is actually birch plywood.

lol, i have no clue. its so hard to tell theses dyas with the online stuff. Its labeled as plywood basswood.... At this stage, it might be better for me to get the stuff i found at michaels thats plywood and $24.99 for a 10 pack

https://www.amazon.com/Basswood-She...ClFbZRPd5ZHf8wMH9iUBlR9Bu9X-kUsIo1nZlZaX7nF8E

 

[Lt72884]

More than the size of the motor, I think it largely depends on the maximum expected flight speed and fin geometry. I've flown an H54 in a rocket with papered balsa fins. It was a light weight and large diameter very draggy rocket (Plasma Dart II XL) so maximum speed was relatively low. But I bet a G80 would be capable of shredding fins if they were too floppy. So it depends....

yeah, this is why i love open rocket AND finsim. Gives me some data to work off of. Wish i had the full version of fin sim, but at least i have the lite version.

The fins i was thinking of were like the tomohawk ISQY type. They have pretty decent surface area and its 4 fins. I have some F and G motors sitting around i want to use. SO i am thinking of just making a 4 or 5 foot tomohawk.

thanks

 

[lakeroadster]

I have thought of this. What has stopped me is my laser cutter wattage (5.5), So im guessing quarter inch basswood fins are going to be better than the 1/8th inch, but heavier. My laser cutter can handle 1/4th inch but it does struggle. It has air assist etc.
What about making my own 4mm ply doing the same technique? I will have to finsim the shape i want to use and compare it to open rocekt sims.

thanks

I've also made 3/32" fins using 3 ply's of 1/32" basswood... whatever thickness you need, you can make.

But as you say, run the numbers 1st, then build accordingly

 

[Lt72884]

I've also made 3/32" fins using 3 ply's of 1/32" basswood... whatever thickness you need, you can make.

But as you say, run the numbers 1st, then build accordingly

yeah, gonna run some numbers in a hour or so. I think i can get basswood to work. I have a scroll saw at my dads house, but that is a few hours from me. Im in an apartment so a jig saw and sandpaper is it or my laser cutter, and maybe 3d printer haha

 

[Hobie1dog]

it most likely will work okay but, I wouldn't try it.

 

[BigMacDaddy]

lol, i have no clue. its so hard to tell theses dyas with the online stuff. Its labeled as plywood basswood.... At this stage, it might be better for me to get the stuff i found at michaels thats plywood and $24.99 for a 10 pack

https://www.amazon.com/Basswood-She...ClFbZRPd5ZHf8wMH9iUBlR9Bu9X-kUsIo1nZlZaX7nF8E

So I don't know how much it matters if it is basswood or birch but what matters more is that it is plywood. I suspect that it is just a 3 ply with two outer wood layers and a somewhat squishy inside filler layer. I use similar stuff for LPR and it works great (1.5mm and 2mm) and is a million times better than balsa in my opinion. However, I am not doing anything close to HPR.

 

[Handeman]

As an HPR flier, I would simply say, NO, basswood will not work.

I don't think the OP defined the question very well. You say HPR, but basswood would not work in a 24 lbs. large L2 rocket. It won't hold up to the landings. I think what you really want to know is if it will work in a large MPR that can fly small H motors that you are calling HPR. You need to constrain your limits better.

The full range of MPR, baby E to full G motors is less Ns than just the range of H motors. I motors are double that yet. HPR includes L2 and L3. With power increases goes weight and size increases. The up part is easy. It will handle the speed sometimes. How will it do when 8 - 10 lbs. of rocket lands on it, on hard ground, at 25 ft/sec?

If you want to use basswood for fins in your rocket, do so. Just understand the physical limits that imposes on how big and heavy the rocket can be and what impact the rocket can withstand in landing and transport.

 

[afadeev]

Amazon seems to have a decent deal right now on 3mm basswood sheets. I have a laser cutter. I have never used basswood so i am curious to know if it will work for hpr fins? I know it works for model rockets, but curious as to level 1 and 2 rockets?

From my experience with basswood, it's will bend further before breaking (vs. balsa), but bend it will.
When you say HP rocket with basswood fins, I visualize fins bending out of shape under the weight of the rocket. Lying on its side during transport.

I used aerofin sim lite to see at what speed fin flutter and divergance would happen and it seems it can handle pretty decent speeds.

3mm = ¹/₈ inch. It's wafer thin.
¹/₈ inch ply is likely too thin as well, but same width unidirectional wood fibers will not be able to resist fin flutter. Much. At all.

I'm not sure what parameters you are entering into Aerofin, but 3mm thin basswood fins are liable to flutter if you look at them funny.

HTH,
a

 

[Lt72884]

From my experience with basswood, it's will bend further before breaking (vs. balsa), but bend it will.
When you say HP rocket with basswood fins, I visualize fins bending out of shape under the weight of the rocket. Lying on its side during transport.



3mm = ¹/₈ inch. It's wafer thin.
¹/₈ inch ply is likely too thin as well, but same width unidirectional wood fibers will not be able to resist fin flutter. Much. At all.

I'm not sure what parameters you are entering into Aerofin, but 3mm thin basswood fins are liable to flutter if you look at them funny.

HTH,
a

i was using 0.125 inches as the parameter. I have used 1/8th inch for a level 2 rocket, but it was birch. I used a j270 motor and the fins held up pretty good, but that was birch. Im thinking its going to be easier to just buy some baltic over the basswood

"basswood fins are liable to flutter if you look at them funny."

lol, that is now noted and in my quotes book haha

 

[Lt72884]

As an HPR flier, I would simply say, NO, basswood will not work.

I don't think the OP defined the question very well. You say HPR, but basswood would not work in a 24 lbs. large L2 rocket. It won't hold up to the landings. I think what you really want to know is if it will work in a large MPR that can fly small H motors that you are calling HPR. You need to constrain your limits better.

The full range of MPR, baby E to full G motors is less Ns than just the range of H motors. I motors are double that yet. HPR includes L2 and L3. With power increases goes weight and size increases. The up part is easy. It will handle the speed sometimes. How will it do when 8 - 10 lbs. of rocket lands on it, on hard ground, at 25 ft/sec?

If you want to use basswood for fins in your rocket, do so. Just understand the physical limits that imposes on how big and heavy the rocket can be and what impact the rocket can withstand in landing and transport.

true, and landing is part of the parameters i have been looking at recently, and i have been worried that basswood would snap.

for motors, it would be H or J's and the weight would be less than 5lbs. I know basswood is flimsy, i was just curious to see what others have done with it.

For the price, i think its best to go with some baltic birch. Michaels has a decent deal on some right now, and its just stronger anyway. If i were to do a larger rocket, i would use fiberglass. I like that stuff so far

 

[BSNW]

I have used basswood on an old 4" high power build . Think I flew a bunch of punchy I motors with no issues. They were off bottom fins and were okay on landing. They did just fine. I saturated the basswood with thin CA. Stiffened them up pretty good. I also beveled the leading edges.

Remember there are birds with tiny bones and feathers that can fly over a 100 mph (Common swift, White-throated needletail). Nature is great like that.

Experiment, learn things, have fun!

 

[tsmith1315]

Experiment, learn things, have fun!

This. This right here.

 

[Getmore]

I use Basswood in some cases if in doubt I'll glass the fins.