Richter Recker - Rail Guides or Buttons

[Martinthomas]

I have a Richter Recker and after a small number of flights using 1/4in launch lugs, I think I need to add rail guides for a more stable take-off.

I am planning to use conformal rail guides from Apogee because I like the wide footprint on the body tube and the mounting area of rail buttons seem too small to be secure on a cardboard body tube.

The launch lugs on the original plan are both within 12in of the rear and behind the CP. Is it critical where the rail guides should be attached? After some browsing, it looks like they should be just ahead of the fins and a little behind the CG.

Any Richter Recker owners out there with suggestions?

Thanks.

 

[MALBAR 70]

I have a RR that I put rail buttons on. I used two buttons on is 1/2" from the bottom and the other is 19 3/8" from the bottom. I have flown it several times and the buttons/guides are the way to go on a long rocket like this. You could also add a third lug a little further up too, I've seen this work as well.

 

[Martinthomas]

Mike, did you epoxy the buttons to the surface of the body tube of did you make a hole and attach to something inside the tube?

 

[MALBAR 70]

I drilled holes and put a blob of epoxy in the opening, threaded the screw into the hole and laid the air frame so the buttons were on the bottom and let the epoxy harden.

 

[byoungblood]

I've used the epoxy blob on a couple of rockets to reinforce the hole for the screw, and so far they've all held up. If you can put the hole into a spot where there's a coupler, baffle, or centering ring, even better.

 

[ksaves2]

I just did a 1/4" launch lug on mine. It's very old and heavy after multiple repairs. The upper tube was crushed and was replaced. The sustainer was smushed and restored with a fiberglass wrap. Heeeeeeeeaaaaaavy!
It will do 1000' on three E12-6's. Fun and slow to watch. I hate to chase two pieces so I did one shockcord and a big chute. Kurt

 

[rstaff3]

If my Mean Machine is an analog, put them 6-12" apart. Drill, apply thin CA to the hole, and install them.

 

[Martinthomas]

I was going to use to use the conformal rail guides from Apogee then realised that they are 54mm and the BT-70 tube is 56mm. Epoxy should take care of the difference, right?"

 

[Steve Shannon]

I was going to use to use the conformal rail guides from Apogee then realised that they are 54mm and the BT-70 tube is 56mm. Epoxy should take care of the difference, right?"

It may fit just fine. After all, it's the inside diameter of a 54 mm body tube that's 54 mm in order to fit a 54 mm motor case.
If not, just put a piece of sandpaper on the tube, grit out, and sand the inside of the conformal guide to fit.


Steve Shannon