TTW?

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ballistic_trep

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Hey everyone! I'm new to the forum and really enjoying it. I'm not so new to model rocketry but have been away from it for awhile. I had a comment from a more experienced builder telling me I should "TTW" the fins on my build. What does "TTW" mean?
 
Through-The-Wall, meaning the fins project though the wall of the airframe (body tube) and are attached (glued) to the motor mount.
 
+1 on what Astron said. They are very strong mounts. You can ad 3 sets of fillets. 1 set on the MMT (motor mount tube), 1 on the inside of the BT (body tube) and 1 set on the outside of the BT.
 
We started a newbies' acronym thread once. I wonder what ever happened to it? I might go look....
 
Hey everyone! I'm new to the forum and really enjoying it. I'm not so new to model rocketry but have been away from it for awhile. I had a comment from a more experienced builder telling me I should "TTW" the fins on my build. What does "TTW" mean?

TTW = Through the Wall, extends tabs on the root edge of the fins through the outer Airframe tube gluing to the internal Motor mount tube and the outer body tube wall.
You mention your not new to model rocketry. If your building Model Rockets - 1/4A - G motors; TTW is the first in a number of UNNECESSARY and Excess Mass inserting OVER BUILDING techniques. Generally if your flying BP motors, even Large Model Rockets butt mounted fins are perfectly fine if properly mounted and epoxy fillets added, TTW is totally unnecessary. Remember WE ARE NOT supposed to be building bulletproof models.

If your building MPR- Mid Power models over 2.5lbs TTW can be helpful Though I personally don't see the need in any model up to the Model rocket/LMR Limit of 1500grams/ 3.3lbs.

In most HPR- High Power Rockets, TTW fin mounting is standard practice.
Hope this helps explain the difference. In short ONE technique does NOT fit ALL model types.
 
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TTW = Through the Wall, extends tabs on the root edge of the fins through the outer Airframe tube gluing to the internal Motor mount tube and the outer body tube wall.
You mention your not new to model rocketry. If your building Model Rockets - 1/4A - G motors; TTW is the first in a number of UNNECESSARY and Excess Mass inserting OVER BUILDING techniques. Generally if your flying BP motors, even Large Model Rockets butt mounted fins are perfectly fine if properly mounted and epoxy fillets added, TTW is totally unnecessary. Remember WE ARE NOT supposed to be building bulletproof models.

If your building MPR- Mid Power models over 2.5lbs TTW can be helpful Though I personally don't see the need in any model up to the Model rocket/LMR Limit of 1500grams/ 3.3lbs.

In most HPR- High Power Rockets, TTW fin mounting is standard practice.
Hope this helps explain the difference. In short ONE technique does NOT fit ALL model types.

I enjoy TTW whenever I feel like it. It is a pleasant building technique to engage in. Heck, even the Estes Crossfire ISX comes stock as a TTW Model, but that does not make it "Bulletproof".
Also, there is nothing in the Rules that says that you HAVE TO build your Rockets as light and fragile as possible, so while you are entitled to your OPINION, perhaps you should'nt try to discourage Folks from practicing or trying new Building Techniques that they may take pleasure in engaging in.
Just sayin'.
 
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I enjoy TTW whenever I feel like it. It is a pleasant building technique to engage in. Heck, even the Estes Crossfire ISX comes stock as a TTW Model, but that does not make it "Bulletproof".
Also, there is nothing in the Rules that says that you HAVE TO build your Rockets as light and fragile as possible, so while you are entitled to your OPINION, perhaps you should'nt try to discourage Folks from practicingor trying new Building Techniques that they may take pleasure in engaging in.
Just sayin'.

Over building is the Bane of Model Rocketry. TTW is an OK technique for large HEAVY rockets as stated in my previous post. But as stated it is a Totally UNNECESSARY WASTE of time and Massive increase in un-needed weight which adverely affects performance of models Rockets being built. While Altitude and ultimate performance are not always the object, keeping our models light is always a PLUS regardless of the model size. Keep our model light does NOT make them Fragile. It makes them fly better. You are welcome to YOUR OPINION also. but I suggest YOU should not Push BAD building on folks just asking for clarification of a particular method. TTW is not and Should not be used on Model rockets.
 
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Over building is the Bane of Model Rocketry. TTW is an OK technique for large HEAVY rockets as stated in my previous post. But as stated it is a Totally UNNECESSARY WASTE of time and Massive increase in un-needed weight which adverely affects performance of models Rockets being built. While Altitude and ultimate performance are not always the object, keeping our models light is always a PLUS regardless of the model size. Keep our model light does NOT make them Fragile. It makes them fly better. You are welcome to YOUR OPINION also. but I suggest YOU should not Push BAD building on folks just asking for clarification of a particular method. TTW is not and Should not be used on Model rockets.

Why the all caps language? Are you aware of how rude it is to shout at people on the internet just because they disagree with you? Did you notice that the OP just asked what TTW means?
When you say that keeping our models light is always a plus, why? On what are you basing that statement?
When you say WE ARE NOT supposed to be building bullet proof rockets, again, why?
You seem awfully angry over this issue, can you explain where all this emotion comes from? Don't worry, you're in a safe place and we all love you. It's all going to be okay.
 
.... but I suggest YOU should not Push BAD building on folks just asking for clarification of a particular method. TTW is not and Should not be used on Model rockets.
The OP's first post on TRF, and one simple question was asked: What is TTW? And Micromeister has to twist the thread into his personal bully pulpit. Shame on you.
 
Hey everyone! I'm new to the forum and really enjoying it. I'm not so new to model rocketry but have been away from it for awhile. I had a comment from a more experienced builder telling me I should "TTW" the fins on my build. What does "TTW" mean?

How about a nice picture ?

thru the wall.gif

From the Info-Central article: https://www.info-central.org/?article=179 which is geared toward the higher impulse models. There are some passionate partisans of various techniques on this forum as you may have already gathered. :) (BTW the fillets don't have to be epoxy.)
 
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You best watch out with that picture, Samb, people gonna get upset because it clearly states "epoxy fillets" which are heavier than other fillets. And if you don't rocket the way they rocket, then you're dumb. I prefer to use jellied angel blood for my fillets since it has anti-gravity effects and smooths with a dry finger.

OP: ttw = awesome. Through The Wall, just like Samb's picture.

Just saw the clarification on the fillets. Doesn't matter, same people gonna make same arguments.
 
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There are two things that are critical in model rocketry (or most hobbies for that matter).

1) Is it safe?
2) Is it legal?

Everything else is technique and should be treated as such.

FC
 
There are two things that are critical in model rocketry (or most hobbies for that matter).

1) Is it safe?
2) Is it legal?

Everything else is technique and should be treated as such.

FC

You forgot number 3.

After satisfying 1 and 2 above, it must be fun.
 
Thanks everyone for the responses. I don't mind the bickering....everyone's opinion matters. My build is an Estes Phoenix AGM scale kit which I'll start after Christmas once my supplies have arrived in the mail and I get this darn cast off my right arm (slipped on ice with an armload of firewood).

DSC02502.jpg
 
Thanks everyone for the responses. I don't mind the bickering....everyone's opinion matters. My build is an Estes Phoenix AGM scale kit which I'll start after Christmas once my supplies have arrived in the mail and I get this darn cast off my right arm (slipped on ice with an armload of firewood).

Wow, nice one ! Good luck with the build and your recovery.
 
I use TTW techniques on my MicroMaxx models.



I'm kidding. Do what works best for you.
TTW wall fins are stronger and you won't see fins torn off at the root edge on a harder ground landing.
If you are a sport flyer getting that extra 20 feet of altitude isn't a deal breaker.
 
Thanks everyone for the responses. I don't mind the bickering....everyone's opinion matters. My build is an Estes Phoenix AGM scale kit which I'll start after Christmas once my supplies have arrived in the mail and I get this darn cast off my right arm (slipped on ice with an armload of firewood).



Awesome choice of Kit!!!
Slightly jealous.;)
 
Since all LPR and many MPR kits come with instructions, I just build according to the instructions. Aerotech's kits have a nice TTW design that actually interlocks with the MMT. I'm glad my Leviathan has TTW, and I'm glad my smaller rockets don't. But bottom line, I just want to have fun, and I don't care too much about competitiom, altitude records, duration records, or velocity records. Build, launch, smile. Hear the woosh. Go get it. Drive home happy.
 
I use lung butter for my fillets whenever it is available. You don't even have to wet your finger as they slide on slicker than a baby's butt yet dry as hard as concrete. This year I seem to have an endless supply. :facepalm:
 
Through the wall fins are well worth the minimal extra weight, with the increased strength they provide in the joint. Everything I build anymore that's the only way I do it. I don't care if it adds 3 ounces.

Build what you like, how you like, and enjoy the hell out of that bigger motor you'll have to burn in the process !!!!!
 
Since all LPR and many MPR kits come with instructions, I just build according to the instructions. Aerotech's kits have a nice TTW design that actually interlocks with the MMT. I'm glad my Leviathan has TTW, and I'm glad my smaller rockets don't. But bottom line, I just want to have fun, and I don't care too much about competitiom, altitude records, duration records, or velocity records. Build, launch, smile. Hear the woosh. Go get it. Drive home happy.

I like the way you think, Bat-mite! I love building scale rockets and watching them fly....doesn't really matter how high they go. Twenty five years ago I had quite a collection of Centuri scale builds....Saturn V, Saturn 1B, Redstone. There are old photos in this house somewhere.....
 
A lot of TARC teams also use TTW fin mounting because they're doing lots of practice flights and would rather not have to reattach any fins after a rough landing. They're looking to keep the aerodynamic profile of their rocket the same as possible and it's nice to build a sturdy rocket that's less apt to need a rebuild on the aft end.
 
Why the all caps language? Are you aware of how rude it is to shout at people on the internet just because they disagree with you? Did you notice that the OP just asked what TTW means?
When you say that keeping our models light is always a plus, why? On what are you basing that statement?
When you say WE ARE NOT supposed to be building bullet proof rockets, again, why?
You seem awfully angry over this issue, can you explain where all this emotion comes from? Don't worry, you're in a safe place and we all love you. It's all going to be okay.

Why Yes I did and did you see that I answered the OP's question completely for all phases of the hobby?
As stated earlier Overbulidling is the Bane of rocketry. No anger it's simply the truth.
Bulletproof building is going to hurt or kill someone, actually there already have been several injuries casued by such vehicles. When someone is killed that will be the end of a hobby I've loved for more the 45years. Over building MUST be serverly scaled back or stopped completely at least for LPR and MPR Models.
The sole purpose of keeping our models as light as possible is to absorb kinetic energy when it hits something or someone rather then transfering it to the object being hit. I build crumple zones into my LRM models just for this purpose.
TTW is just another example of totally unnecessary building that actually weakens the outer airframe particularly if using thin-walled body tubes, Granted TTW is the standard method used in HPR but the OP was not asking about HPR. As stated earlier there are other methods that have proven over the years to be just as secure as TTW without cutting slots in the tubes. Epoxy rivet method is one such technique used on Larger models, not standard size few ounce to 1.5lb Model Rockets But those heaver model or with Clear Lexan fins. This proven method even works on materials that do not accept glues or adhesives like Polypropylene. Standard Butt mounted fins are perfectly fine for the majority of Model Rocket builds, and if double glue joint mounting wood to wood or wood to paper(cardboard) are stronger then the two materials being joined. Add a simple Fillet to these joints they will stand up to most any non-ballistic impact. Another point is the lighter we construct the model the LESS LIKELY it is to be damaged by a no deploy or Chute Wadding ball recovery. I have a couple hundred models build without a single TTW fin many of which have 30 or more flights without a single fin joint damage. Some of the tips get rounded off being dragged but the Fin-Body joints stay firmly attached.
And one more thing: While it is true leaving the Cap Key locked on while typing an entire sentence or paragraph is considered shouting or being rude. Using Caps to draw readers attention to a specific word or phrase is Not being rude it's used extensively in writing as an attention getter. There is no anger simply drawing attention to important points or items.
To think or believe the use of any All caps is always shouting is another mistaken reading of PC rules.
Hope that answers your questions.

Edit: As always we all have the right to build our models anyway we wish, but we also have the obligation to express opinions concerning Keeping our Hobby the Safest outdoor Sport/hobby on the planet.
Over building is such a threat.
 
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John, whatever side of a particular discussion I might be on I always find your contributions (and your amazing photo gallery) valuable. Your point about weakening thin-walled tubes by slotting is (or should be) well taken. As far as the OP building an Estes Phoenix, I think adding tabs to the motor mount for those rear rectangular fins a reasonable upgrade that, by itself, doesn't qualify as dangerous overbuild.
 
Just to clarify,

On the left - a flush joint.
On the right a butt joint.

Flush Joint B.jpg Butt Joint A.jpg
 
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