When to go from 101 to 1515 rail guides?
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COrocket
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My general rule is anything built for the possibility of over K impulse, or greater than 4" in diameter. It's not the strength of the 1010 rail I'm worried about, its just that at most clubs the away pads generally have 1515 rails which is necessary for the L+ impulse safe distances.
Yoehahn
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COrocket said:
I do the same. I catch he'll for it tho, but If I have a 22lb rocket on a 6 grain K (almost L) and there is only one rail with 1010 buttons out there on the range it's stupid to put 1010's on because them you just wait unnecessarily. Sometimes the dont even put the 1010 out there too
jsargevt
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I think that the general rule of thumb that I have seen is: if you have to ask use 1010.
Basically, you should have enough experience by the time you have a rocket which needs 1515 rail that you'll know that you need 1515 buttons. Just what I have observed on this forum. The suggestions above look about right. Your mileage will vary.
No rule of thumb, really, just whatever makes you comfortable.
I flew my L3 project with 1010 buttons - about 7 1/2" diameter, 9' tall, 42lbs on an M motor. It has flown several times without issue. I only have 1 rocket with 1515 buttons and it is 7 1/2" diameter and comes in about 50#.
Motor impulse has very little to do with what kind of buttons you use, other than the fact that typically rockets with high impulse motors are heavier. The issues is usually diameter and weight. The real stresser on the buttons is getting the rocket vertical. 1515 buttons and their associated larger mounting screws can logically handle more weight and the side-to-side torque that might occur when getting the rocket from horizontal to vertical. I would never put 1515 buttons in a 4" rocket regardless of weight, but that's just me.
Eastern flyers use the big Unistrut buttons on large rockets. We just acquired a large pad with a unistrut a few weeks ago and that is the first Unistrut we have on site.
--Lance.
I flew my L3 project with 1010 buttons - about 7 1/2" diameter, 9' tall, 42lbs on an M motor. It has flown several times without issue. I only have 1 rocket with 1515 buttons and it is 7 1/2" diameter and comes in about 50#.
Motor impulse has very little to do with what kind of buttons you use, other than the fact that typically rockets with high impulse motors are heavier. The issues is usually diameter and weight. The real stresser on the buttons is getting the rocket vertical. 1515 buttons and their associated larger mounting screws can logically handle more weight and the side-to-side torque that might occur when getting the rocket from horizontal to vertical. I would never put 1515 buttons in a 4" rocket regardless of weight, but that's just me.
Eastern flyers use the big Unistrut buttons on large rockets. We just acquired a large pad with a unistrut a few weeks ago and that is the first Unistrut we have on site.
--Lance.
I have used 1515 on 4 inch rockets. To me, it is just preference. I personally would not go above 30 lbs with 1010.
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I've used 1010 rails for a 5" P. Our rails have a a baker tube for about 8-10 foot.
Tony
Tony
what is a baker tube?
ECayemberg
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Agree with Lance and Tony.
I generally don't add 1515 buttons until rockets hit 50+ lbs. Have flown a 60+lb 8" diameter M safely off a 1010 "standard" rail. That said, my larger rockets will often include a pair of 1010, 1515, or Unistrut on opposing sides to have some flexibility in selecting a pad.
-Eric-
I generally don't add 1515 buttons until rockets hit 50+ lbs. Have flown a 60+lb 8" diameter M safely off a 1010 "standard" rail. That said, my larger rockets will often include a pair of 1010, 1515, or Unistrut on opposing sides to have some flexibility in selecting a pad.
-Eric-
When to go from 101 to 1515 rail guides?
When you decide to be a real man and leave the greasy kid's stuff behind.
When you decide to be a real man and leave the greasy kid's stuff behind.
ClayD
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charlie baker?
Probably a backer tube... Kind of like Up aerospace uses....
https://www.upaerospace.us.com/Lockheed-Martin-Reusable-Rocket-Plane-Launch.html
when the beam stiffness of the rail is not correct for what your doing, you can mount the rail to a Beam, or Truss system so it wont rod wip. Either stiffer, or not stiff but reinforced.
sodmeister
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I would think more importantly ,is how the screw holding the button is attached ,and not the size of said button.A 1010 RB with a good long SS machine screw drilled/tapped into a solid backing is not going to tear off due to rocket diam. or motor size,when this happens ,human error is usually at fault.
A 1515 button and screw ,stuck in a hole in the BT with a slathering of epoxy is not necessarily stronger...is it ?
Paul t
A 1515 button and screw ,stuck in a hole in the BT with a slathering of epoxy is not necessarily stronger...is it ?
Paul t
Clearly, what you assert is true, however ...
All things being equal, i.e. given the same mounting technique; a larger diameter, deeper-threaded screw will be stronger. IIRC - 1010 button uses a #8 screw, 1515 button uses a 1/4" screw.
--Lance.
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Thank you. I have never seen it called that.
cjl
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I generally start using 1515 once I get above about 4 inch diameter, but I've used 1010 successfully up to about a 40lb rocket on a fairly hefty M. 1010 will support a surprisingly large rocket - the bigger factor is often what pads are available at your local club. If your club tends to put 1515 rails out at the L+ pads (which is common with a lot of clubs), then that should be your cutoff.
H_Rocket
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A #8 screw has a nominal tensile strength of 850 pounds and a 1/4-20 is rated at 1600 pounds so yes, more metal is going to be stronger. I would assert the if you use two well mounted buttons, either size is going to provide much more strength that you will ever need.
I do know that 100% of my personal button failures have been in the mount. Those failures have usually occurred because I put a stupid amount of torsional loading on the button as I try to get it on the rail. Once it is on the rail, I got a $20 bill that a properly mounted set of 1010 buttons could guide a 200 pound rocket up the rail with no problem.
sodmeister
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I agree totally ,especially when it comes to shear strength.If somebody shears a #8 SS screw/bolt off a mount ,taking into account how much of that fastener is exposed throught the rail button (not much) then something is wrong.But I can see the safety/feel better factor using 1515.
Paul T
dixontj93060
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I agree. In fact, I'm much more worried stable ascent and will move to three 1010's (two aligned closer to aft of airframe) like on this M-class rocket, than to move to 1515's.
sodmeister
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Funny you should mention "lugs" as there a couple of kit manufacts. (Loc & PML) that sell high power kits that come with Estes type 1/2" lugs....I mean really
So there you go ,another fly in the rail button ointment as it were LOL
Paul T
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