rocket perch

tooth

Well-Known Member
TRF Supporter
Joined
Aug 19, 2022
Messages
56
Reaction score
52
Location
Kansas
I think that's what they are called from what I've read. A system to keep a rocket lifted who's fins do not extend below the motor so the motor is held off the blast plate prior to liftoff. How do you pros do it? I'm totally lost, lol. Thanks for the help (don't need to say I am REALLY new at all this)
 

heada

Well-Known Member
Joined
Jan 18, 2009
Messages
5,513
Reaction score
2,917
Location
Indianapolis, Indiana
O a rail, you can use a bolt with thd bolt head in the rail and a nut to hold it in place. Use a 2" or 3" bolt and it'll support dozens of pounds of rocket.

On a small rod, use a spent engine casing on the rod itself or block of 2x4 sitting on the blast plate. For larger rods (1/4" and bigger) you can get a 1" long section of metal tube. Brass bushing works well. Drill and tap for 1/4-20 and then use a 1/4-20 bolt to tighten on the rod. If you use a 2" or 3" bolt, it'll support the rocket.
 
Joined
Oct 2, 2016
Messages
10,140
Reaction score
9,575
Location
Hawaii
I believe the term you're looking for is a standoff.
As mentioned clothes pins and spent engine casings will do the job. If the nozzle of the spent engine casing is too small then just ream it out, then slip it over the launch rod.
Masking tape wrapped around the launch rod and binder clips will also work. As will an empty beer can. (Waste not want not). On rails I have used a C clamp. Then there's this:
https://www.siriusrocketry.biz/ishop/oddl-rockets-raise-spring-1046.html
Whatever floats your boat.
Cheers.
 

JimByrne

Well-Known Member
TRF Supporter
Joined
Jul 19, 2020
Messages
151
Reaction score
90
Location
Kingman, Az.
I use a small block of aluminum (1" X 1/2" X 1/2') with a hole in it to slide over the launch rod and another hole threaded (10-32) to hold a T-bolt which pinches against the rod. This will fit under the bottom of the rocket and keep it above the blast plate at whatever distance you want.
I made a bunch of these and have them on all our launch rods.
 

neil_w

OpenRocketeer
TRF Supporter
Joined
Jul 14, 2015
Messages
15,021
Reaction score
8,833
Location
Northern NJ
I'm a big fan of the spent motor casing. Just slip it over the rod and you're good to go.

There are times when you might want to lift the rocket quite a bit further up the rod, like with some spinning saucers. That's when a clothespin is good to have around.

In any case, we're talking super-low-tech here. Just something (anything non-flammable, basically) to support the rocket on the rod.
 

tooth

Well-Known Member
TRF Supporter
Joined
Aug 19, 2022
Messages
56
Reaction score
52
Location
Kansas
I really appreciate all the ideas and suggestions from you folks, thank you. I'm still building my launch pad so will explore some of your ideas when it's ready.
 

techrat

Well-Known Member
TRF Supporter
Joined
Jul 18, 2022
Messages
843
Reaction score
683
Got to Home Depot and steal some of those paint Stir-Sticks. Using that as a base, cut one approximately in half. Take the slightly longer one, and chop off two thin pieces off to make some feet. Now glue the two halves, one on top of the other to form an "X" shape. Then glue those feet pieces to the underside of the upper piece so the whole thing stands even. That's your base. Glue a spent motor casing to the center of the X, and once that's all dry, you can place the rocket on it as a standoff.
 

techrat

Well-Known Member
TRF Supporter
Joined
Jul 18, 2022
Messages
843
Reaction score
683
FYI, you can also grab some dowel at home depot that's approximately the diameter (or slightly smaller) of a motor, and use that in place of a spent engine casing. I prefer the dowel, so I'm posting it here as an option, but if you want to do it for zero dollars, use the Stir-Stick and engine casing method.
 

tooth

Well-Known Member
TRF Supporter
Joined
Aug 19, 2022
Messages
56
Reaction score
52
Location
Kansas
the really funny thing about this is I'm still building my first rocket as well, so have no spent motor casings, lol
 

tjkopena

Rocketship Games
TRF Sponsor
Joined
Feb 18, 2021
Messages
248
Reaction score
422
Location
Philadelphia, PA
the really funny thing about this is I'm still building my first rocket as well, so have no spent motor casings, lol

I'd use a clothespin then. I keep a handful in my field box, they have lots of uses. But if it's a small-ish rocket you can also just use some masking tape to create a tab to hold the rocket, like kuririn mentioned. Loop it around the rod and then out & doubled back on itself to make a ~1/4in tab that'll keep the launch lug from slipping over it.

If the kit came w/ a helper tube for inserting the engine block, like the yellow tube in lots of Estes kits, you could also use that somewhat similarly to a spent motor.

Basically, don't overthink it.
 

tooth

Well-Known Member
TRF Supporter
Joined
Aug 19, 2022
Messages
56
Reaction score
52
Location
Kansas
here's my first effort - a screw-in lug epoxied to a flat mirror hanging tab. To hold it in place I pushed a small brad between the lug and the rod. It works, but isn't very elegant. I'll have a look at that spring idea.
PXL_20220908_142857644.jpg
 

dhbarr

Amateur Professional
TRF Supporter
Joined
Jan 30, 2016
Messages
8,716
Reaction score
3,105
You can hand drill an appropriate hole in the side of an aluminum turnbuckle.

I like this because I can tie the whips to the screw eye ( or hook, if you so choose ).
 

tjkopena

Rocketship Games
TRF Sponsor
Joined
Feb 18, 2021
Messages
248
Reaction score
422
Location
Philadelphia, PA
here's my first effort - a screw-in lug epoxied to a flat mirror hanging tab. To hold it in place I pushed a small brad between the lug and the rod. It works, but isn't very elegant. I'll have a look at that spring idea.

If the tab's conductive you should cover it with electrical tape or epoxy or something, so it can't short the igniter leads.
 

BigMacDaddy

Well-Known Member
TRF Supporter
Joined
Apr 30, 2021
Messages
1,657
Reaction score
2,336
Location
Northern NJ
Roll of masking tape in the field box is really useful. Even if you use rail-based launch setup tape works well as a standoff (although it leaves sticky residue)...
 

BABAR

Builds Rockets for NASA
TRF Supporter
Joined
Aug 27, 2011
Messages
10,457
Reaction score
5,071
Masking tape wrapped around the launch rod and binder clips will also work.
only problem with masking tape is it gums up the rod when you take it off. So be careful if your next rocket on the rod has a lower position on the rod, it an grab and delay your smooth slide up the rod.
 
Top