Launch Guides for 29mm Minimum Diameter?

Hello!

I am currently designing a 29mm minimum diameter rocket and shooting for maximum altitude. I am struggling to figure out what to do as far as launch guides go. Ideally, I could use a launch tower, but I haven't seen any plans for one that I have the time or resources to build right now. I was looking to use linear launch lugs, but I can't seem to find any designed for air frames less than 38mm. So I guess my other two options are rail buttons or regular launch lugs. Could anyone who has experience with this point me in the right direction? Thanks!

Launch lugs are lighter and only need to last for 0.2 seconds :wink:

I'm working on a 3D-printed fly-away guide concept for 38mm, and if I get something working could be persuaded to try 29mm. Keep an eye this thread

If you are shooting for "maximum altitude", ANY sort of rail guides/buttons/lugs will work against you. Especially on something as small as 29mm (ie: relative size/drag of the buttons).

Bill's (possibly) forthcoming flyaway guides would be great, but they aren't available yet. If you can wait, they seem like an excellent solution. If you can't wait, making something similar yourself would not be all that difficult (reference the Apogee tutorial for ideas), though they probably would be a bit more crude and not as slick.

You could also go with "mini" or "micro" buttons available from rail-buttons.com. This would cut down on drag over standard buttons, but not eliminate it. However, you will also need to get a matching rail to use them, so this may or may not save you any time/effort/money.

I'd highly recommend building your own launch tower as the best solution. It's really not all that difficult. Search the forum (and elsewhere) and you will see there are lots of ideas and designs people have used to home-build something, many of them inexpensive and relatively simple to do.

Whichever way you go, post your build and flight pics/stories,
s6

Thanks for the replies everyone! I found some launch tower ideas that do seem pretty simple so I might take a crack at it. I'll also be looking to see how those fly-away guides do!

What is the OD of your tube, and is it one of proline's? I have another version of the fly-aways I'm working on that is hinged and should be a little more durable with very fast flights...I might be willing to take a crack at making you a set.

I'm actually getting pretty close to having 29mm guides available.

wfcook said:

I'm actually getting pretty close to having 29mm guides available.

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VERY, very cool. I've wanted to do a 29mm MD, and this could be the final push. I'd be in for a set once they come to market!

Nate

wfcook said:

I'm actually getting pretty close to having 29mm guides available.

Click to expand...

Awesome, I'm just about done with a nice CF 29mm minimum diameter that I'd love to try them on!

Here is the set I made for RAHagen's glassed paper tube, which happens to be exactly the same diameter as a standard-wall FG tube (but a good bit lighter). I just have to get a sample of 29mm thin-wall tubing to check that size (which I will do at the next launch when AMW gets here) and then I should be ready to go. AMW will be carrying these:

Ready and waiting. Great job.

How long do you guys think the 29mm guides need to be? Shortening them makes them lighter, of course...

How long is it now?

The rail guides are 6" long.

I think you could probably do 4"-5".

I think 4 or 5 inches would be enough. On my Argent, I used about 6" separation and that's fine, so I would think 4" or 5" on a 29mm airframe would work fine.

Nate

nute said:

I think 4 or 5 inches would be enough. On my Argent, I used about 6" separation and that's fine, so I would think 4" or 5" on a 29mm airframe would work fine.

Nate

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Exactly and these are also above the fins closer to the CG.

conman13 said:

Exactly and these are also above the fins closer to the CG.

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Yeah absolutely, they should probably be just about right on the CG for most rockets.

Nate

I'm going to try a set at 4.6" (which is a convenient length to reduce to without redesigning much) and see how it looks. Thanks, guys

Agreed. And i'll take 2.

Ok next question: is the demand mostly standard-wall FG or mostly LOC paper and thin wall FG?

wfcook said:

Ok next question: is the demand mostly standard-wall FG or mostly LOC paper and thin wall FG?

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I haven't used them, but it seems to me that you could just buy the larger version (standard-wall FG) and then for the thinner tubes put a thin spacer, i.e. tape/foam/etc., to make up the small difference in size. Not as elegant but functional I would think.

I'll take a 29mm standard-wall FG one as soon as you have them ready! (my 29mm minimum diameter rocket is handmade CF and somewhere in between the thin wall and regular FWFG). In 2 weeks I hope to fly it on F and then a G at my home field (and film it at 240 fps to see the guides in action), and if that goes well, then I'll be flying a 29m 6GXL I243 at MDRA. I was planning on using my tower but these would be much more convenient

wfcook said:

Ok next question: is the demand mostly standard-wall FG or mostly LOC paper and thin wall FG?

Click to expand...

+1 Make them For the slightly larger Regular FG and can tape/shim for smaller. 1 product multiple uses.

Here they are in the shorter length, and next to a set of orange 38mm guides:

RocketHunter said:

In 2 weeks I hope to fly it on F and then a G at my home field (and film it at 240 fps to see the guides in action), and if that goes well, then I'll be flying a 29m 6GXL I243 at MDRA.

Click to expand...

I will want pictures!

Resurrecting this thread... What is the projected availability of the 29mm rail guides? I flew my Mongoose 29 twice at LDRS using a 38mm rail guide with a 29mm-38mm paper motor mount adapter slit in half to make it fit. It worked "OK", but I really want the real thing... as did just about everybody else with a Mongoose 29 that I've spoken with.

OK, I'll get back on it. I had a slight delay involving an unscheduled job change which has derailed R&D for a little while, but I should have my act together soon.