Rails vs Rods

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DynaSoar

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Why rails?

I got a set of Acme rail guides along with their fin can. I can't see much benefit to using them vs. a lug. They have a greater cross-section from what I can tell, ie. more drag. What am I missing?
 

Micromeister

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Be very careful using anything form Acme...I'm sure you've seen what happens to the cycote:D

I think it has more to do with the stiffness of the Rail over a Rod than adding or detraction anything to the model. Rail buttons may have a slightly smaller impact on HPR models than tube type lugs. I don't use rails so I'm just guessing, but I can't see any benifit to buttons over lugs on lpr or mpr models. Personally I'd just a soon skip the lugs altogether and launch from a tower.
 

Johnnie

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No "rod whip" with a rail. Your bird usually comes off the end in a straight line...better stability. The "whip" at the end of a rod can determine where your rocket is going.

Personal preference, as I fly everything straight up, and the rail will shoot it where you point it :D

Everything but my Estes and Questes rockets get the button...
 

lalligood

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Primary reason for a rail is no rod whip as was previously mentioned. Another benefit--despite being mentioned less frequently--is that the rocket doesn't move on the pad. Ever been flying on a windy day trying to ignite a stubborn Copperhead as the rocket keeps twisitng on the rod & tweaking the ignitor? :( That's not an issue with a rail...the rocket doesn't move. :D

Rail buttons are also items that can be retrofit onto any rocket. Nothing (or no one) says that you can't have both lugs & rail buttons/guides on the same rocket!

Just the opinion who is very happy with only using rails... :cool:

HTH,
 

radiO

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i'm very interested in the rail setup. can someone pretty please show me a picture of what you guys are talking about. i went to Railbuttons.com and couldn't tell what was going on.
thank you!
 

stevem

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maybe these diagrams will help.

A lot of guys here use rail and rail buttons for thier larger birds. I use it for everything. My smallest rockets are the Estes Cluster Bomb and the Estes Paveway and I even use rail buttons on them.
 

stevem

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buttons on rocket...

I have seen some guys use 3 buttons. Most of my rockets just use 2 and I have had no problems.
 

stevem

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here's my pad with an Estes Storm Caster on the rail.
Not a very good picture but you get the idea...
 

rstaff3

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99.9 % of my MPR and LPR rockets (not counting saucers, etc) have buttons. I have put them on most of my larger LPR rockets also. The really work great for something like the Mean Machine which has a problem with wind-loading on the pad. One added benefit is that when the lines get long at our LPR launches, I can put up a rail and get a flight on most any round, via a a separate and seldom used bank of pads.
 

DynaSoar

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Originally posted by Micromister
Be very careful using anything form Acme...I'm sure you've seen what happens to the cycote:D

I think it has more to do with the stiffness of the Rail over a Rod than adding or detraction anything to the model. Rail buttons may have a slightly smaller impact on HPR models than tube type lugs. I don't use rails so I'm just guessing, but I can't see any benifit to buttons over lugs on lpr or mpr models. Personally I'd just a soon skip the lugs altogether and launch from a tower.
Thanks.

Yeah, I'd rather use a tower too. But if I want to play with the other kids and use their toys, my toys have to fit. My tower isn't particularly portable. If I don't stop building up such a ground support collection I'm going to need a van for the birds and a trailer for the equipment. Not that I think that's a BAD thing, it's just more spendy than my smarter half will allow.
 

lalligood

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Originally posted by stevem
maybe these diagrams will help.

A lot of guys here use rail and rail buttons for thier larger birds. I use it for everything. My smallest rockets are the Estes Cluster Bomb and the Estes Paveway and I even use rail buttons on them.
These diagrams are *excellent* for explaining how rail buttons work & how they should be attached to the rocket.

Great job! :D
 

DynaSoar

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Originally posted by lalligood
Another benefit--despite being mentioned less frequently--is that the rocket doesn't move on the pad. Ever been flying on a windy day trying to ignite a stubborn Copperhead as the rocket keeps twisitng on the rod & tweaking the ignitor? :( That's not an issue with a rail...the rocket doesn't move. :D

Now THAT is a reason. I can get behind that kind of thinking.
Where do I find a rail that'll fit a 1/4 rod mount?
 

stevem

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not sure you can mount a rail to 1/4" - seems like that may be kinda flimsy.

To mount my rod, I bolted a 1/2" x 12" steel rod to the rail leaving 6" of the rod extending below the rail. The rod is then inserted into a 1/2" hole drilled in my launch pad.

How do you other rail guys mount your rail to the pad?
 

stevem

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for blast deflector I first used and old 14" chop saw blade. I would simply insert the 1/2" rod on the bottom of my rail through the center hole of the chop saw blade and into the pad mounting hole.

I used that for quite awhile before making a blast deflector that is a variation of the one found here
 
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