Planet express, just a thought

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Not necessarily. There are low thrust, high impulse motions, and also the opposite. E.g.:

D22 = LPR
H13= HPR

To a certain extent thrust and impulse are correlated, but there is a lot of variation.
D22 and H13 have the same power but are classified according to their impulse, as LPR and HPR?

Impulse = thrust x time (I = Ft, where F is generally not constant), that's the correlation.
 
D22 and H13 have the same power but are classified according to their impulse, as LPR and HPR?

Impulse = thrust x time (I = Ft, where F is generally not constant), that's the correlation.
The LPR D22 motor has higher average thrust than HPR H13 motor despite being four impulse classes lower, because it is a much (!) shorter burn.

In the fictional example you gave previously, you said:
A case of high impulse with low power, would be a 1 lbs model rocket taking an hour to go from 0 to top speed. Not very common (never happened).
Well, maybe not an hour, but the H13 burns for ~15 seconds, whereas the D22 burns for .9 seconds.

The point is: high impulse does not necessarily imply high power (thrust), within limits.

I apologize if I'm not correctly understanding the argument you're making.
 
The point is: high impulse does not necessarily imply high power (thrust)...
Unclean! Power is not (thrust). Power is thrust times speed, which can be quite high even at low thrust if the speed is high. Or quite high at low speed, if the rocket is just crawling along despite high thrust (i.e. if it's very heavy). When drag is insignificant, power is d/dt(½mv²), but when some of your power is lost to drag T∙v is a better expression.
 
You're right, I was confusing power and force. That makes the use of the term "power" even weirder, because we don't really ever talk about it. We talk about thrust and impulse. Also, power is inherently dependent on the rocket; a draggy rocket will go more slowly and therefore reduce the power value. Thrust and impulse are purely motor characteristics.

(hopefully I am not getting lost in confusion here... it's really off-topic anyway, so I'll shut up now)
 
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I’ve gotten the body tube in and cut down, and the matching stuffer tube. Will post updates when my centering rings come in. About a week out on the nose cone
 
Will super glue hold basswood to a nose cone perms a toy? Was going to epoxy the side stripes on, but thought super glue may be a better choice. Opinions?
 
Will super glue hold basswood to a nose cone perms a toy? Was going to epoxy the side stripes on, but thought super glue may be a better choice. Opinions?
For wood-to-wood, I use carpenter's glue when I can. If it's structural, heavy or needs impact resistance, then I use some kind of epoxy, or add epoxy fillets.

I use superglue to avoid having to hold parts together while drying. Also, sometimes when I take great care in aligning parts and I want to avoid disalignment while they dry.

Between superglue and carpenter's glue, for me, it mostly depends on whether I feel like holding the parts together for seconds, or for minutes, and what will work better to make sure the parts end up being aligned.
 
In general, I avoid superglue for structural joints. Remember the old Krazy Glue commercial, with a guy hanging from an I-beam suspended by a single drop of glue? Yeah, the stuff is great when it's loaded strictly in tension. But wood workers, machinists, and others use it for a temporary hold, because once you're done you only have to give the joint a modest whack sideways and it lets go real easy. (I have done this.)

It also doesn't adhere to all materials, failing in particular on some plastics (and working fine on others).

I consider it simply no good for a permanent joint that's going to see any significant load (since it's very rare that such loads are fundamentally, completely tensile). I use it now and then for hardening permeable materials, and for temporary holds such as @Funkworks described or those I will be taking apart, but that's all.

All that said, I'm not completely clear about your proposed application.
Will super glue hold basswood to a nose cone perms a toy? Was going to epoxy the side stripes on, but thought super glue may be a better choice. Opinions?
Was that a typo, "perms a toy", or is it one of those new words the young folk use these days? (Get off my lawn!) I guess the side stripes are thin basswood strips, flexing to conform to the curve of the nose cone? IF the strips are thin enough that they don't stick out into the air stream, and IF superglue will adhere well to whatever the nose cone is made of, then I guess you could go that way. But personally I wouldn't.
 
In general, I avoid superglue for structural joints. Remember the old Krazy Glue commercial, with a guy hanging from an I-beam suspended by a single drop of glue? Yeah, the stuff is great when it's loaded strictly in tension. But wood workers, machinists, and others use it for a temporary hold, because once you're done you only have to give the joint a modest whack sideways and it lets go real easy. (I have done this.)

It also doesn't adhere to all materials, failing in particular on some plastics (and working fine on others).

I consider it simply no good for a permanent joint that's going to see any significant load (since it's very rare that such loads are fundamentally, completely tensile). I use it now and then for hardening permeable materials, and for temporary holds such as @Funkworks described or those I will be taking apart, but that's all.

All that said, I'm not completely clear about your proposed application.

Was that a typo, "perms a toy", or is it one of those new words the young folk use these days? (Get off my lawn!) I guess the side stripes are thin basswood strips, flexing to conform to the curve of the nose cone? IF the strips are thin enough that they don't stick out into the air stream, and IF superglue will adhere well to whatever the nose cone is made of, then I guess you could go that way. But personally I wouldn't.
Yep good old autocorrect. Apparently I don’t know how to spell permanently. It is thin balsa, and I think flexing of the parts may cause axial force, so epoxy it is. Thank you all for the sage advise
 
Why not extra boogy in the giddy up?
or measure rockets in BSI, the Boot Scoot Index?

lol, HOR definitely delivered a chuckle. That would mean alot of us keep HOR's in our garage, just dont tell the wife how much I pay for them

Hey honey, I’m going to a launch this weekend.

Ok have fun. By the way, is this launch for whores or lepers?
 
Progress thus far. Body tube is mounted into the tail cone. I have the side trim mounted and filled with DAP sealer. Centering ring is fitted, just not glued in yet. I am holding for the nose cone which should be done this week, and I realized I ran out of 29mm mmt.59F4CC03-2158-472F-8C34-F41DAE1936DC.jpeg8AEB06D4-35D3-4FDD-89D0-03AA07182839.jpeg311B3A32-B9E6-480B-97FD-52702A3EBAA4.jpeg76613CE4-53C1-434D-B482-4E946577B2DB.jpegB9A13E53-A104-43AD-903C-D57FB646A0BB.jpeg
 
High Oomph Rocketry. Recall our exchange a little while ago about technically incorrect use of the word "power" as a generic term that sometimes means thrust, sometimes impulse, occasionally energy, and only rarely actually means power. You or someone countered with the accepted term "high power rocketry" even though the real differentiator there is impulse. I asked that we make a habit of using a different word for the more general notion of how much "go" there is, and suggested "Oomph". I ended my part of the exchange by referring to HOR. (I also inadvertently made you think I was picking on you in particular, which I promise I never was.)
Would be a plug for F and G powered rockets (MOR rocketry.)
 
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Nose cone is filled, primed and sanded. Still need to knock the primer down and take it to 320 grit. Right now it is at 180. Next step is motor mount and launch lug. I have no clear path forward with launch lug, still mulling it over
 
... I have no clear path forward with launch lug, still mulling it over
Rail guides on the bottom? If you're into displaying it horizontally, you could always add removable landing gears.
 
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Next step is motor mount and launch lug. I have no clear path forward with launch lug, still mulling it over

Should be able to hide the launch lug by placing it against the left or right side fin under the rocket. That way you can move it out to clear the curvature of the fuselage.

1664198915639.png
 
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Good options all. The weight of the nose scared me off of putting a lug on the fin, didn’t know how much force would be exerted. I wonder if I could camouflage rail buttons in two of the windows on the side. As long as they are straight it shouldn’t matter if the rail buttons aren’t centered on the body right?
 
Good options all. The weight of the nose scared me off of putting a lug on the fin, didn’t know how much force would be exerted. I wonder if I could camouflage rail buttons in two of the windows on the side. As long as they are straight it shouldn’t matter if the rail buttons aren’t centered on the body right?

I had planned to make an internal 3/8" launch lug since this rocket has an elliptical body shape. That would not be to difficult with a wooden nose cone, but might be a bit more tricky with 3d printed nose? But maybe not?

Something to consider.

1664203003455.png
 
I had planned to make an internal 3/8" launch lug since this rocket has an elliptical body shape. That would not be to difficult with a wooden nose cone, but might be a bit more tricky with 3d printed nose? But maybe not?

Something to consider.

View attachment 539216
Internal may be the way to do it. There’s plenty of room in the body section, and getting it through the nose is no problem, mines solid wood as well. Also will keep the nose and body radially aligned. I think that basically settles that then.
 
View attachment 539181View attachment 539182View attachment 539183View attachment 539184View attachment 539185
Nose cone is filled, primed and sanded. Still need to knock the primer down and take it to 320 grit. Right now it is at 180. Next step is motor mount and launch lug. I have no clear path forward with launch lug, still mulling it over

there IS a way to do this, but it Requires some skill and guts.

fifire out the max diameter of the rocket BODY without the nose cone.
drill two hole, one forward (probably just under the ”lip”) and one tailward. That wil fit a paper body straw or MicroMaxx body tube. Put the tube in, leaving a bit forward and a bit aft, and glue in place and let dry.

trim loosely, then sand it back until edges are smooth. Make sure the body tube side is clear of fins and put main lug there. The nose cone is rotateable, so as long as both are STRAIGHT and EQUIDISTANT from centerline, it fits. Pull a @neil_w and leave a bit forward, paint it like a cannon, or somehow otherwise make it look like “part of the plan” rather than an afterthought.


https://www.rocketryforum.com/threads/tank-killer-caught.157129/
 
there IS a way to do this, but it Requires some skill and guts.

fifire out the max diameter of the rocket BODY without the nose cone.
drill two hole, one forward (probably just under the ”lip”) and one tailward. That wil fit a paper body straw or MicroMaxx body tube. Put the tube in, leaving a bit forward and a bit aft, and glue in place and let dry.

trim loosely, then sand it back until edges are smooth. Make sure the body tube side is clear of fins and put main lug there. The nose cone is rotateable, so as long as both are STRAIGHT and EQUIDISTANT from centerline, it fits. Pull a @neil_w and leave a bit forward, paint it like a cannon, or somehow otherwise make it look like “part of the plan” rather than an afterthought.


https://www.rocketryforum.com/threads/tank-killer-caught.157129/
Guts all day… skill, that’s what body filler is for
 
No. Renaming HPR is a fight I would most certainly loose, and won't attempt. Avoiding the incorrect use of "power" whenever I can is a practice I will continue (using "oomph" as the generic term unless a better one comes along). I will also continue, only now and then, to ask others to join me. And I don't expect to use "HOR" again unless it should ever again become possible to use as an inside joke.
I thought Oomph was the first integral of mojo.
 
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