Chuck

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"It's a rocket......what could go wrong?" Neil McGilvray

"It is difficult to get a man to understand something when his salary depends upon his not understanding it".--
Upton Sinclair

Len, at PARC launches there is no real RSO but what you should do is require all rockets to provide evidence that they are safe for any given motor in either the form of a manufacturers rec motor chart or by providing sim info for scratchies. As Chuck said, there is a 5:1 rule. I could bash up a spreadsheet or a little VB app if you like.

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The likelihood of a successful launch is inversely proportional to the number of people watching.

Quoted Text Thanks for taking the time to convert your thoughts into a working spreadsheet.

No problem. It's something I've been meaning to do for a few years now, you just gave me the shove I needed I hope you find it of some use.

Quoted Text Have you considered making it a VB addition to your RockLog Program?

I was thinking of making it in VB but decided to make sure I had it all working in excel first - that will save me a lot of time when I do make a VB app. RocLog is MS Access, but I think I will make a suit of tools and add them to the PARC downloads page. I could put this functionality into Roclog, but I think I'd rather keep it as it's own entity.

Quoted Text Just some wild thoughts

I would rather any software I write be free because I write stuff because I want people to use it. I am not bothered about trying to make any money out of it (I doubt anyone would pay for something that does very simple maths anyway).

Quoted Text both spectators and flyers should be safer.

Not to mention the most important thing...the rocket!

Quoted Text Accurate Rocksim performance predictions for "scratch built" deigns as we all know are reliant on more than just airframe geometry.

Very true, and well spotted! Once a rocket has been designed and built, you should go back into rocksim and make any weight changes. Of course most people do not do that and at the end of the day, it's the RSO's call. Showing the 5:1 ratio is true of your rocket/motor should make any RSO happy. But as I said before, the 5:1 rule is not ALWAYS right - going a bit outside of the ratio is still ok, but you start to push safety when you do so, and anyone who has ever flown an underpowered rocket will tell you it was not a lot of fun, esp when that rocket cost you a lot of time, money and effort.

Quoted Text I not sure how accurate many scales are at lower weights ie 10's of grams.

You can get scales accurate to 2g for about $60 or so. For smaller parts you need 'powder' scales (0.1g) and these cost around $300.

Quoted Text This being the case a simple "weigh in" with a triple beam balance of the complete airframe as whole (Airframe. Motors, Recovery timers tracking powder electronics and batteries etc.) would provide, what I think would be a more accurate GLOW.

Yep. And that can be done at the RSO table prior to launch. If you use that spreadsheet you can make a sheet for each flyer and their rockets so you dont need to weigh the airframe all the time.

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Quoted from Tarpazium, posted September 12th, 2006, 9:01am at here Hey Chuck Any chance of getting a hold of such a chart ? (I would hate to think that it was I, who "re-invented the wheel"?) Tarpazium

I've contacted the boys, and hopefully I'll have a copy before to awful long. If nothing else you can compare notes.

Chuck

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"It's a rocket......what could go wrong?" Neil McGilvray

"It is difficult to get a man to understand something when his salary depends upon his not understanding it".--
Upton Sinclair

Just emailed you some charts, Tarp.

I wouldn't say no to a chart or some spreasheet indicating GLOW Vs Initial Thrust

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Why Limit Yourself?

I've posted the chart to

http://homepage.mac.com/wesrudy/SafeWeightRatios.xls

Along with this from Neil McGilvray.

"As requested....

On the 5:1 sheet all you use is the motor (average Ns) number. The letter designations are meaningless for this form and are not included. Say the motor is a J-350.....find 350 and that will tell you what the safe 5:1 thrust to weight ratio is. The same number will apply to say an H-350 or a K-350.......the safe 5:1 stays the same. On the safe weight ratio sheet...it works the same way but acts as a quick reference to see what the 4:1 and the 3:1 ratio are. This helps if you are under and need to make a decision or are building a big project and getting a little thin on motor power.....

Neil"

I haven't looked at it yet, just sent it along.....hopefully it will work for ya.

Chuck

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"It's a rocket......what could go wrong?" Neil McGilvray

"It is difficult to get a man to understand something when his salary depends upon his not understanding it".--
Upton Sinclair

I've started work on 'max loft' - I have a sample here for you to play with. I have only done from A to E motors so far. Please download and play with it and give me some feedback before I go any further.

http://waro.iinet.net.au/parc/maxloft.exe

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The likelihood of a successful launch is inversely proportional to the number of people watching.

If anyone downloaded max loft prior to the date/time of this post, then have another look - It's been redesigned and I think it is much better. I think I will go with this design, so I'll finish it off in the next few days.

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Thanks for the programs and spreadsheet, guys!

edit: oh yeah, can I just confirm the terminology being used? It's based on average thrust not initial thrust, yeah? Neil's note says so, but I just want make sure I'm not getting myself confused.

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Last modified September 17th, 2006, 9:07pm by matthew

yes, it's the average thrust. And the total impulse has no meaning (eg: as far as the maths go, a H180 is the same as a J180 - both have an ave thrust of 180n)

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The likelihood of a successful launch is inversely proportional to the number of people watching.

Quoted Text Would that mean that being a two stage rocket the weight of the second motor (the D12-7) was included as "dead weight" in GLOW calculations, as their is NO thrust until the rocket is ignited at 500 feet beyond lift off?

No, thats a very good point and illustrates the importance of beta testers! Maxloft as it is would look at your example and think 'cluster' not staged. So I will have to shove in an option button to select staged or clustered. I think this also answers your other questions?

Quoted Text As a quick visual check, could the actual GLOW Ration be expressed prominently on the interface as a "ratio" with perhaps conditional formatting

I could do that and did think about it, but I decided that the required thrust was more important and informative than a ratio which does not tell you very much. But I will take it on board.

Quoted Text Impakt - Apart from these questions, I think MAXLOFT is a brilliant and simple tool that should be on every RSO's Laptop for Launch Registrations.

thanks It can only get better from here and your feedback will make it so! cheers

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The likelihood of a successful launch is inversely proportional to the number of people watching.

ok, I've made some changes...

1) There is now a check box next to each motor called S/AS (staged or AirStart). Selecting the check box for any given motor will take the motor weight into account, but not it's thrust as upper stage and air start motors are dead weight at lift off. There is a small problem with this in that if you check a box, then uncheck it and check it again, the info will be wrong. I am trying to fix this.

2) 'total average thrust' is now 'lift off average thrust'. this along with the above mentioned check boxes clears up the problem with staged vs clusters.

3) Ratio is now displayed (but not formatted 100% correctly). A message will also be displayed if the ratio is too low.

4) Added tool tips. download

download: http://waro.iinet.net.au/parc/maxloft.exe

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Quoted Text Looks Seriously Cool .... in fact (and please don't take this personally), it looks like something my 16 year old daughter would wear.

I was going to use a nice mellow 'stone' type texture, but I thought 'bugger it!' I'll use something more adventurous. That is a wallpaper I made with a 3D app (bryce).

Quoted Text I am unsure if this figure should include the overall mass including the motors or just the airframe alone?

Just the airframe weight. The motor weight is added when you select a motor. This caused a heap of problems with the S/AS options and took me about 5 hours to nail.

I might also point out that the rocket weight uses an interger variable, so It will probably ignore anything after a decimal point. For the purpose of this app, a whole gram is close enough I think. Using a single precision float would just add to memory consumption.

Quoted Text Which to me seems outrageously high.) How do the calculation compared with your own flying experience or anyone else's who may be reading this thread?

Firstly, your calc is wrong. the D12-0 should have the S/AS option selected because it is a staged motor (S/AS = Staged or Air Started Motor. These motors do not have their thrust used in the calc - only their weight is added to the GLOW because they are dead weight at lift off). So you should have ended up with a ratio of 7.69 : 1

I checked all calcs with a spreadsheet. My AMRAAM 2 is marginal (bottom limit) on a G33, but flys well enough, but you would not want to go any lower.

Quoted Text Alternativley is 5:1 GLOW Ratio perhaps too conservative a ratio?

It is a bit conservative, but it garuntees safe lift off. The min safe thrust value is -25% of 5:1 and that seems more like it - but my own experience says that exceeding the min safe thrust reported by max loft is asking for trouble. You should never cut it fine where thrust is concerned - you just place your rocket at risk. You dont want to fly an under powered rocket...it's a waste of motor and money (and possibly rocket too).

Quoted Text Any chance of using the same background for this forum?

No! But I did use it was wallpaper for a while, and I think It was quite nice and soothing.

Quoted Text Looks great ---- Can you change the background to RED?

Since you like red so much, I am emailing you a very nice red wallpaper I made a few years ago. Enjoy!

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Quoted Text In fact it worked extremely well with "Bryce" and another MetaCreations product called "Poser".

Bryce was actualy a Corel Product. Or it was for a while...Bryce is still available, but is now owned by some no name company I think. I also have poser 4.

Quoted Text One Question though.... "Where should I stick it ???"

Trust me, you DO NOT want me to answer that!

Quoted Text I've tried the following code but it does not seem to work.

I'm not sure the deal is with html and this forum...most code is supposed to work, but it obviously doesnt.

Quoted Text Impakt- This looks like it could induce a "heart attack" or it may even be the product of one.

Reminds me of post nose-bleed mess myself. I think I am the only person who likes that image! I think it is pretty cool.

Quoted Text So I should have selected "S/AS" against the "flying motor" (D12 -0) and not the non=flying motor (D12-7) ? Is that what you are saying?

What I am saying is I have no idea what I'm saying!

You should select S/AS against the upper stage motor (D12-7) not the D12-0.

Quoted Text There is a small problem with this in that if you check a box, then uncheck it and check it again, the info will be wrong. I am trying to fix this.

That has been fix btw...

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The likelihood of a successful launch is inversely proportional to the number of people watching.

Quoted Text Reminds me of post nose-bleed mess myself. I think I am the only person who likes that image! I think it is pretty cool.

This nasal fixation, you've sought professional help?. Is there any chance, that it was caused by a traumatic childhood event, in which you either stood too close to or even over the top of a launching rocket, was it?

Tarpazium

P.S. A rocket up the nose,........ now that would be a real buzz.... not to mention clearing your sinuses

Tarp

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Life is too short - Why not eat dessert first.

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Last modified September 21st, 2006, 4:20pm by Tarpazium

Quoted Text This nasal fixation, you've sought professional help?

Yes I have...I has going to have my nose cut off to prevent a number of problems (nose bleeds, bad smells, boogies) but then I would have no where to park my fingers when they are idle

Back to busines...

I have added K - N motors to max loft and I also added a manual/over ride group so you can check GLOW for motors that are not in the list, such as hybrids. I have also changed the rocket weight variable to a single float so that you can have a rocket that weighs more than 38kg.

I am quite pleased with it now. I just have to make an icon for it and that will be it.
I will post the final version soon...tomorrow maybe.

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The likelihood of a successful launch is inversely proportional to the number of people watching.

Are the thrust figures used to calculate the ratio the average or peak thrust of the motor? I think I read somewhere that the 5:1 ratio is used with the AVERAGE thrust of a motor for a rough guide. The peak thrust at the beginning of the burn on black powder motors is the real decider of wheather its gonna leave the rod at a high enough velocity to remain stable. This would also be influenced by the Cp and Cg relationship and fin area. The initial fin area on liftoff of the two stage jobbie you fly is quite high and so I think you could probably fly on a smaller ratio and still have a stable flight.

My two cents worth........may be wrong???

It is the average thrust that the ratio is based on and peak or initial thrust does not enter the equation.

The 5:1 ratio is just a guide - if you have a 5:1 or better ratio, then you'll be right. Max loft tells you if you are below the 5:1 ratio but still considers you right to go if its above 3.8:1 or there abouts...why 3.8:1? Thats because I consider 33n the minimum I would fly my AMRAAM on - any less would be a problem, so I used that as a base line for minium required thrust. That's not to say 3.8:1 is fine for all rockets - it could cause one of your birds to arc into the ground.

But as I said, if you stay about 5:1 or better then you'll be right. Under powering a rocket is a pointless exercise. It will just cause you grief when you have to dig it out of the ground.

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The likelihood of a successful launch is inversely proportional to the number of people watching.

Gotta agree with ya astroboy. You may have even read it in Tarpaziums opening spiel to this very thread.

At the end of the day, I believe that a fairly simple guideline has been molested into an ultra-simplistic variance that fornicates with arbitrary values to produce an inordinately overcomplicated field tool. (phew, deep breath)...

To have it suggested that RSO's should all have it on their laptops for use in the field has me gobsmacked. What ever happend to a simple pocket calculator. Or better yet, a piece of paper folded up in your back pocket.

This may be rocket science, but IT'S NOT ROCKET SCIENCE! (insert image of Animal from the muppets after a drum solo!)

And as for the guideline itself. OK, 5:1 was chosen. Seems reasonable. But let's see, if my rocket / engine combo is outside of this, then it's also been suggested that 4:1 or even 3:1 is OK!!?!?!?! What sort of a guideline is that!

Plus, these are the sort of things that you work out, not only before the launch day, but even before you hand over your $$ to buy said engine. Who leaves it to 5 mins before the launch? Who can afford to? And if that's the case, then do we get the RSO to cut up our steak into small, easily chewable pieces too?

Not wanting to take anything away from you though, Impakt. I think it could be a handy tool have. Sitting around the computer, having a couple of beers and discussing the world of rocketry, the subject of G.L.O.W.'s arrises - Hold that thought fella's, I've got Impakts(tm) GLOW Worm(c) software here.

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Randomness is propaganda perpetuated by the uninformed.

If you dont like it or think it's a waste of time, then dont use it. Simple.

With all the crap going on at the moment, now is not a good time to give me a hard time.

And you are right scoop...maybe I over reacted. I am very stressed right now.

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Last modified September 28th, 2006, 11:12am by Impakt

Geez Impakt....you sound a bit stressed out, I think what Fridge is trying to say is that there are anomalies in the "Rule of Thumb"....I didn't read anything about having a swipe at you!

With all that is going on I think you may have misinterpreted something.

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Why Limit Yourself?

Quoted Text If you dont like it or think it's a waste of time, then dont use it. Simple. With all the crap going on at the moment, now is not a good time to give me a hard time. And you are right scoop...maybe I over reacted. I am very stressed right now.

It's about now that I wish I'd seen your original post, It's OK, I've got fairly thick skin.

I find singing in the shower - loud (& probably out of tune too) - to be one of the best remedies for stress relief. A great way to start the day. Guaranteed to get rid of ulcers and make you live longer too.

Now, whilst I'm not going to offer you my undying love, I do find you to be intelligent, quite level headed, enthusiastic about rocketry and a responsible moderator to boot.

I certainly can't - and won't - speak for everyone. The impression I get is that this is quite an open & friendly forum and no-one would direct anything to another individual in the negative (sans Tripoli Vic. it seems). Whilst posts may initially come across as negative, I'm sure that they aren't intended to target a person. Like you've mentioned in the past, text doesn't translate well the nuances that speech and expression provide.

My negative is not with you but with the subject: Thrust v GLOW and it's application.

Now, if I can just get back up on my pedestal and continue my rant...

Quoted Text At the end of the day, I believe that a fairly simple guideline has been molested into an ultra-simplistic variance that fornicates with arbitrary values to produce an inordinately overcomplicated field tool.

Let's try an Estes Executioner shall we. I'm sure we've all seen one go.

1: ...a fairly simple guideline...
What's your peak thrust? Look up my engine data, E9 = 19N.
: Get out your calculator > 19/4.45/5 = 0.854lbs = 387g max
: or, Look up your sheet > 19N = 387g max
What's your rocket and engine weigh? Get out the scales, 383g
Yep, you can fly.

2: ...ultra-simplistic variance...
What's your average thrust? Look at my engine, E9 = 9N
: Get out your calculator > 9/4.45/5 = 0.404lbs = 183g max
: or, Look up your sheet > 9N = 183g max
What's your rocket and engine weigh? Get out the scales, 383g
Look, ah, I hate to be the one to say this, but ah, on your bike buddy.

3: ...molested...
The ol' Executioner won't ever be the same again. Now I'm gonna have to modify the manufacturers design and do away with the manufacturer's recommended engine and load in something with an average thrust equal to:
(383g)/(1000g)*(2.2046lbs)*(5)*(4.45Nlbs^-1) = 18.8N or an ?19.
This leaves possibly E23's or F22's. Here Ol' Ex ol' buddy, get that up your arse.
Now, since this thread was started in the interests of safety, we've now gone outside both the Rocket Manufacturer's recommendations and the Engine Manufacturer's recommendations.

4: ...arbitrary values...
Hey fella's could ya let me fly if it's 4:1 - Sure
E9 = 229g
Sorry, on yer bike.

What if we made it 3:1
E9 = 305g
Look, we've told you, get outa here.

Mate, what if we made it 2.38:1
E9 = 385grams
Mate, welcome back. An Executioner you say, It'll be good to see that one go. Lets all get behind the 17' of Electron Beam Launch Controller to watch the launch of a rocket that we originally rejected as being over 200% UNDERPOWERED for a safe launch.

5: ...inordinately overcomplicated field tool.
I'll get the piece of paper out of my back pocket, you go set up your laptop. And that's all I have to say about that...

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Randomness is propaganda perpetuated by the uninformed.

Actually, no it's not. I forgot your software.

Don't get me wrong, I've written programs that do pretty much the same thing. Take what's a simple calc and apply an interface to it. And I do it 'cause it's fun.

I mean, once you've done one Sudoku game what else is there to do on a lunch break but write a program that'll do the rest for you!

When I said about the beer around the computer, I mean't it. Sarcasm or belittlement wasn't intended at all.

I personally wouldn't have chosen those colour's though...

And I guarantee you'll step out of the shower with a smile if you sing at the top of your lungs while in it.

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Randomness is propaganda perpetuated by the uninformed.

I did not make up the 5:1 guidline and you will find it works well with AP motors.

This guideline is the result of the colective wisdom gained from millions of rocket launches over 50 years. I dont think any individual is in a position to poo poo such collective experience. It may not be right every time for every situation, but 600million launches can't be wrong.

I agree that the above example is pretty much bollocks, but then I belive the ratio was intended for AP motors - not end burning BP motors. Again, the 5:1 is only a guide for you to decide if you are going to launch or not. It gives you an indication of the thrust to weight ratio - simple. If the manufacturers motor matrix says it will fly on x motor, then it probably will.

As an example, my modified executioner was flown a week or two ago on an F22. I knew this was asking for trouble and it was. Glow worm placed it at 3.82:1 and the rocket only just got off the launch pad - right on the money. The same is true with other rockets in my fleet that I know are under powered on x motor. I DID actualy test this thing and I HAVE launched a lot of rockets.

It is not the be-all-end-all of the story because there are a whole range of other issues that will affect the reality of a rocket flying or not, and that is why I allowed for a bit of fat (3.8:1) before warning that the rocket may not fly - this just tells you the rocket is under powered and I've said it before and this is the LAST time I will say it - if you want to waste time and money by under powering a rocket - great - you do that - it is after all, your time and you money to waste.

If you want to use a calculator to work out the maths - thats great too. Carry a motor weight chart in your pocket. No probs.

The 5:1 ratio is simply a guidline used in rocketry. You do not have to like it. You do not have to agree with it, but some clubs enforce it.

And yes, glow worm was made out of boredom more than anything and

Quoted Text I personally wouldn't have chosen those colour's though...

No need to puke on it...there is a twisted logic behind the colours, multiplied by the fact I wanted to break the rules for once.

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Last modified September 29th, 2006, 4:06pm by Impakt

Don't have a COW........ man!

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Why Limit Yourself?

(sigh)

Fridge: For the record, your Honour, I'd like to call to the stand Jimmy Neutron.

Courthouse: murmer, murmer, murmer

Fridge: Jimmy, could you please tell the court my stand on the 5:1, Peak Initial Trust to GLOW ratio.

Jimmy: Well Fridge, I believe you stated that it seems reasonable.

Fridge: Jimmy, did I at anytime disagree with the collective wisdom gained from millions of rocket launches over 50 years.

Jimmy: No Fridge, I don't believe you did. In fact, in the example provided, I believe in section 1, entitled "a fairly simple guideline" you used the unadulterated version as used by millions of people around the world, to show that the Estes Executioner was a safe rocket to fly with an E9 engine.

Fridge: Jimmy, with your experience, would you say that an F22 Engine is bigger, say, than an E9 engine.

Jimmy: Why yes it is Fridge. The F22 not only has a greater total impulse, but also a greater average thrust than the E9.

Fridge: So, Jimmy, would I be correct in saying that if an E9 was determined to have an adequate amount of thrust for that rocket, then an F22 would as well?

Jimmy: Yes Fridge, it would.

Fridge: So if I modified a rocket that would, as the manufacturer intended, run on an E9, what modification would be required to make that same rocket faulter on an F22?

Jimmy: Well Fridge, there are many things that could of happened. Alot of calculations would have to be done of course, but most likely would be that the fillets were done with a cement render of some kind.

Fridge: Jimmy, I'd like to thank you for your time.

Jimmy: You're welcome.

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Randomness is propaganda perpetuated by the uninformed.

Quoted from Impakt, posted September 29th, 2006, 11:39am at here I did not make up the 5:1 guidline and you will find it works well with AP motors.

Surely Thrust Vs GLOW is the same regardless of propellant?
If you use AVERAGE thrust as your calculation ....YES AP motors will fit the equation better.

Quoted Text As an example, my modified executioner was flown a week or two ago on an F22. I knew this was asking for trouble and it was. Glow worm placed it at 3.82:1 and the rocket only just got off the launch pad - right on the money.

What the heck do you build your rockets out of? ....Concrete?

How did you manage to get an Executioner to ask for trouble using an F22?

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Why Limit Yourself?

I am not having a cow Scoop, but I am getting a bit frustrated, mostly because I dont think I am getting my message across. So appologies if I sound like I am having a rant, but I'm not.

Look, you guys will have to do some googleing to answer your questions in detail. I know what you are trying to say, and I am obviously not doing a good job at answering your questions. There are many variables that can affect the reality of the 5:1 ratio in relation to any given rocket/motor. I am just trying to tell you that this is a guide/best practice. Thats all.

As to my executioner, it pretty much exactly the same as an estes one, but made out of quality LOC parts - that means ply CR's instead of the paper things you get in the estes kit (you want to see me have a cow? Be around when I examine the parts in an expensive estes kit!), a stronger BT instead of the thin crap the estes one is made from and a LOC NC, instead of the rubbish that comes with the estes kit (when I trashed my executioner, the BT went THROUGH the NC - there is a photo of it on the parc gallery).

My executioner also packs a 29mm motor mount. So add up all that and then throw in a 29mm motor which weighs a lot more than an E9, and you end up with a bird that weighs half a kilo which does not want to fly on an F22.

Quoted Text Surely Thrust Vs GLOW is the same regardless of propellant?

Not if the ratio was derived from AP flights. AP and BP have different burning characteristics and therefore the 5:1 ratio might ONLY apply to AP motors and not to BP motors or hybrids. Even though both have an average thrust, other factors do play a part such as initial thrust and so on. Average thrust is just used because it is a guide, not a scientific equation for minimum required thrust (if it were, you would need to know everything else about the rocket and factor that into the equation too, plus other variables such as current atmospheric conditions).

I think that exhausts this topic, or at least I am exhausted!

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Quoted Text Well Fridge, there are many things that could of happened. Alot of calculations would have to be done of course, but most likely would be that the fillets were done with a cement render of some kind.

I dont see how you can make these comments since you know nothing about the rocket in question. The only original parts are the fins. I know how the rocket is built, I know it is built well and not over the top for the desired motor and I know how it performs on an F22. I can only view these comments as being a bit naive and slighty rude.

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Last modified September 29th, 2006, 9:12pm by Impakt

The 5:1 ratio will safely get your 1 pound rocket off the rail.

Now if your 1 pound rocket is 2' wide, it will still get it off the rail successfully, before air resisitance and other forces which may doom the flight.

Regardless of size, the 5:1 only deals with the weight. That rule is successful getting you into the air, after that it all depends on other rules of physics. If you have 20 fins on it, flat NC, huge diameter those factors will affect your rocket once it gets into the air.

Ns are Ns, and average Ns whether with APCP, N2O or BP follow the same rules. A hybrid motor with 65 degree N2O producing 1,000 average Ns follows the same weight rule as an APCP motor producing an average 1,000 Ns. The fact that when the N2O increases in temps it loses average impulse quite simply means the average Ns have dropped, so the safe rocket must be be lighter. In short the same amount of N2O at 75 degrees would only have 980 Ns of average impulse then a successful 5:1 would come from a different number.

All the above numbers are for this debate and not actual, as nitrous increases in temp it decreases in average impulse but increases it's peak impulse. Quite simply hot N20 makes motors burn at a higher peak briefly, but at a lower average.

Now is that clear as rain, or clear as mud?

Chuck

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"It's a rocket......what could go wrong?" Neil McGilvray

"It is difficult to get a man to understand something when his salary depends upon his not understanding it".--
Upton Sinclair

Quoted Text Regardless of size, the 5:1 only deals with the weight. Ns are Ns, and average Ns whether with APCP, N2O or BP follow the same rules.

Thanks Chuck....I am glad you cleared that point up.

Quoted Text Look, you guys will have to do some googleing to answer your questions in detail. I know what you are trying to say, and I am obviously not doing a good job at answering your questions.

Impakt, we are not having a shot at you or asking you to validate the 5.1 rule, we are simply saying there seem to be anomalies in it.
I thought forums were supposed to be for open and informative dialog, asking questions to stimulate thought processes in other members, or using the wider expierences of members. I did not assume you were having a rant

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Why Limit Yourself?

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Last modified September 30th, 2006, 7:26am by Scoop1261