Tim, what would be the issue with the club buying it from GLR? By all means bring it out so we can check it out. If it fits our needs and everyone says great, we'd probably prefer the club own it so that if we damage it we won't feel as bad.

Warren

Looks great to me. My only question is what keeps the uprights so rigid? You'd think w/o a ring or similar brace up top it would "splay" outward? Guy lines or wires will only make that more of an issue.

If we could drop a big ring around the top, run bars supports from that ring to the exterior of the black uprights, we'd have a pretty bulletpoof tower.

As it sits, I think I'd be a wee tiny bit hesitant to put my M project on there - 25:1 thrust to weight ratio. That said, this tower gets us 99% of the way there and I make a motion we buy it as a club. I realize that few of us would use it - but I think we all are glad we have Estes pads and hybrid equipment, even though not everyone uses those. This just makes us a more complete club.

If the club doesn't want to buy it, I will and I'll rent it back 😉

Personally, if I were to drop my own money on a tower, I'd get that tower launcher you and I are always drooling over (www.towerlauncher.com) and call it good. Hell, with that it'd be a very unlikely thing for me to ever put on rail buttons or launch lugs on any bird at all...

Warren

That sucker was $1800 five years ago. I have a hard time taking them serious. There is a reason they don't put a price on the website. I wonder if they have ever sold any of them? I'd bet if you commissioned something similar from someone capable it could be done just as well for twenty cents of the dollar...

We need to buy GLR's. Thoughts on my suggestion re: the upper ring?

JW

I think we should look at it before we go making any suppositions about how rigid the uprights are. Rings are for towers that aren't built well enough to maintain their spacing from bottom to top. The Bicycle towers definitely qualify, I don't think the tower launcher does given the backing truss behind the rails. This tower looks a bit better built than the bicycle towers. Let's see it before we worry.

Warren

We need to buy GLR's. Thoughts on my suggestion re: the upper ring?

Looking at the picture, the supports appear to be 1" square steel tubes. If the base that they're welded to is beefy enough, I bet a rocket would have a very hard time putting enough lateral force on those tubes to make them bend appreciably. I'm tempted to dig up my old textbooks (wait, this the age of Wikipedia now, what am I thinking?) and do some calculations to see how much the bar ends might flex for a given force.

But better yet, let's buy the thing, grab the ends, and try to wiggle them. More scientific that way.

Could the club get the tower in time for MHM?

From the perspective of the executive committee, it didn't even get discussed at the last meeting. IF Tim brings one to the launch as he's offered and people fly off it and like it, we'll buy it.

Warren

If this matters Ill need a tower for 3" rocket

Of course it matters and Tim has said he'd bring the tower for the April launch. It's a done deal. Relax, load a motor and get ready to punch holes in the sky.

Partly because I wanted to be able to do some small-motor testing of altitude birds near home, and partly because I had an idea and wanted to see if it would work, I built my own tower this weekend.

It has three 5' x 1" diameter tubes with 1/4" bolts sticking out the end that screw into a 3' square plywood base that's reinforced with T-nuts on the bottom and laminated with galvanized steel on the top. So far I have installed T-nuts for 24mm minimum-diameter rockets, and I'm going to follow up with holes and nuts for 13mm, 18mm, 29mm, and 38mm birds. The ring at the top holds the ends of the tubes in an adjustable fashion, and can accomodate a 4" total fin span. The ring at the top is a PVC coupler, so 4" PVC could be attached below the ring (making it a tube launcher?) or above the ring for a tall windscreen.

If people like it, I'll donate it to the club, though I may borrow it back in the near term for my own local launches.

Will there be a tower at MHM this year to fly a 54mm? -Sean

Yes, we will be bringing the larger tower as well as the "bicycle tower" that's usually in the trailer.

We will be able to accomodate your 54mm bird.

Ed

Sounds great. Thanks!