launch lug dimensions?

[bjphoenix]

I've got a few old launch lugs that I'm going to use for current scratchbuilds. For 1/8" rod the launch lugs measure about 5/32" diameter. I observe that frequently the 1/8" lugs seem a bit snug on a normal rod. What I don't have is a lug for 3/16" rods so I am going to "roll my own". And strangely enough the only problem I've had with a rocket hanging on the rod during launch was using a 3/16" lug on 3/16" rod. I may roll mine just a bit larger than 7/32".

One of my current builds is an Estes Goblin. I pulled its pieces out of the bag and measured- it has 2 pieces of launch lug that are only 3/8" long. I think my Estes ESAM also has tiny little launch lugs like that. I think the tiny little piece of launch lug is strong enough, but it doesn't give much area to glue to a tube. I had a launch lug come off of a rocket during launch many years ago and it wasn't good so now I'm careful to put several layers of glue fillets on and even over the launch lugs.

Has anybody else had problems with tight launch lugs? Launch lugs coming off of rockets?

I should have added this- the rockets with tiny 3/8" long launch lugs had 2 of them so you can locate them on the airframe pretty far apart. I think this is better than having one launch lug that is 1" or 2" long.

 

[dhbarr]

I usually only have trouble if I get a ridge of glue or drop of paint in there. I don't carefully measure though -- if a clean launcher tries to bind I just switch to the next smaller rod.

 

[lakeroadster]

Has anybody else had problems with tight launch lugs?

I typically use a Scotchbright pad to clean the launch rod, wipe the rod with a clean cloth and then apply silicone lubricant. That does wonders.

Launch lugs coming off of rockets?

As long as you sand the body tube and the lug where the glue will attach the two together, and sand them such that you can see the fibers of the cardboard, the bond will be such that the only way they will come apart is to shred the cardboard.

Hope that helps.

 

[bjphoenix]

I typically use a Scotchbright pad to clean the launch rod, wipe the rod with a clean cloth and then apply silicone lubricant.

We clean our launch rods but maybe not frequently enough. I was thinking you could clean off the rod and then put some lubricant on it such as wax, but the repeated launchings would probably burn off the wax pretty quickly. Maybe wax or other lubricants don't help that much. I wonder if it would help to highly polish the rod with high grit sandpaper? If it's a near mirror finish would the motor residue come off easier?

 

[lakeroadster]

We clean our launch rods but maybe not frequently enough. I was thinking you could clean off the rod and then put some lubricant on it such as wax, but the repeated launchings would probably burn off the wax pretty quickly. Maybe wax or other lubricants don't help that much. I wonder if it would help to highly polish the rod with high grit sandpaper? If it's a near mirror finish would the motor residue come off easier?

It rally has more to do with what the rod is made off or what it is coated with. The 5/16" diameter steel rod I used is zinc plated, so it's pretty slick. I bought it at Home Depot.

 

[DigBaddy]

We clean our launch rods but maybe not frequently enough. I was thinking you could clean off the rod and then put some lubricant on it such as wax, but the repeated launchings would probably burn off the wax pretty quickly. Maybe wax or other lubricants don't help that much. I wonder if it would help to highly polish the rod with high grit sandpaper? If it's a near mirror finish would the motor residue come off easier?

I sand my basic steel rods with coarse to progressively finer sandpaper to get them smooth, then they get turtle wax on them to prevent rust. Once the launch day is over, quick wipe with fine steel wool, wax again and are ready for the next use. They're absolutely slick as snot on a doorknob.

 

[4regt4]

Launch lugs supplied in kits seem to differ in size. The lugs in an old Estes Executioner kit I assembled would barely fit on a 1/4" rod, where other brands of kits had lugs that were quite loose. And the 3/16" lugs in an Estes MultiRoc were kind of snug.

Hans.

 

[bjphoenix]

Launch lugs supplied in kits seem to differ in size. The lugs in an old Estes Executioner kit I assembled would barely fit on a 1/4" rod, where other brands of kits had lugs that were quite loose. And the 3/16" lugs in an Estes MultiRoc were kind of snug.

I was building a long BT60 rocket with 24mm mount for D12. I rolled launch lugs out of paper using a 15/64" drill bit as a mandrel.

 

[DigBaddy]

Launch lugs supplied in kits seem to differ in size. The lugs in an old Estes Executioner kit I assembled would barely fit on a 1/4" rod, where other brands of kits had lugs that were quite loose. And the 3/16" lugs in an Estes MultiRoc were kind of snug.

Hans.

My Multi-Roc came with 1/8" lugs. I think your sizes are off. I would expect the Executioner to have had 3/16" lugs, but I've never built one.

 

[BigMacDaddy]

FWIW -- these work very well as 1/8" launch lugs (and you get more than you will ever need for $2). I use CA glue to attach them to rocket bodies. ID = 4mm (.16")

https://www.hobbylobby.com/Party-Baking/Party-Supplies/Balloons/White-Balloon-Sticks/p/53558

 

[4regt4]

My Multi-Roc came with 1/8" lugs. I think your sizes are off. I would expect the Executioner to have had 3/16" lugs, but I've never built one.

The Executioner kit most definitely had 1/4" lugs. But it was an older kit (Ebay) that surprisingly had plywood fins. No kidding.

But, as to the MultiRoc. You're right. I forgot that I upsized the lugs when I built it, but I used Estes sourced 3/16" lugs.

Hans.