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1/4" launch lug material

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BDB

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I'm in need of some 1/4" launch lugs, and I don't want to wait for them to ship from a supplier. The drinking straws that we have are too small, but surely there are some easy hacks for this.
 

dave carver

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Hobby store brass tubing? You can get it off the display and get it with a 1/4" ID.
 

markkoelsch

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If you have fiberglass or Carbon fiber arrow shafts handy they should work.
 

Lowpuller

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Bojanlges or McDonalds straws are bigger than regular straws and will work fine.

I have also used the brass tubing.
 

les

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The drinking straws that we have are too small, but surely there are some easy hacks for this.
How much smaller? If just slightly smaller try this.

Get 2 straws (lugs) and slit them down the center

Wrap a layer or 2 of wax paper over your 1/4" rod. Fit one straw over this. It will be expanded out with a gap because it is too small.
Apply a layer of glue, and fit the second piece over the first piece. Have the slits on opposite sides (so if the first slit was at 12:00 or 0 degrees have the slit for the second straw at 6:00 or 180 degrees). Let dry and remove.
 

terryg

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The tubes that Aerotech high power igniters come in are perfect for 1/4 inch launch lugs and are free. If you cannot wait for a launch, then get some of the larger drinking straws and wrap them in masking tape so that they can be glued reliably.
 

rstaff3

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The tubes that Aerotech high power igniters come in are perfect for 1/4 inch launch lugs and are free. If you cannot wait for a launch, then get some of the larger drinking straws and wrap them in masking tape so that they can be glued reliably.
The Firstfire tubes are my favorite source of lugs, although I have also used brass and aluminum hobby tubing.
 

Incongruent

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I'm in need of some 1/4" launch lugs, and I don't want to wait for them to ship from a supplier. The drinking straws that we have are too small, but surely there are some easy hacks for this.
Plastic disposable pen tubes are the right size. Attaching them might be difficult though.
 

Lowpuller

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Oh great BK you may have just made him angry. We can only hope the angry Launch Lug doesn't show up now..............
 

MikeyDSlagle

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Local hardware store may have nylon, brass or aluminum standoffs that will work. And probably copper or brass plumbing stuff.

Some coat hangers have a cardboard tube on them that may work.

They are easy to roll your own too. Wrap your rod, if you have it, with a wrap or two wax paper, then smear glue on white paper or kraft paper and wrap it around that. Can attach it while it is still wet too. Or use paper self stick labels.

Maybe the right size syringe? The medicine ones.
 

qquake2k

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I've never used a big launch lug. I use rail buttons on all my MPR and HPR rockets. But if you're launching by yourself and don't have a rail, that might not be an option. There are a lot of good ideas here.
 

BDB

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I've never used a big launch lug. I use rail buttons on all my MPR and HPR rockets. But if you're launching by yourself and don't have a rail, that might not be an option. There are a lot of good ideas here.
You surmised the problem correctly. I'm planning to build a launch rail using a jaw stand, but I want to launch something MPR-ish this week. I can whip up a simple PVC pad with a 1/4" rod after a quick trip to Lowes.

I found a few 3D printable rockets on Thinigiverse.com that have 1/4" lugs. I'm a complete noob at 3D printing, but I think I'll try to print some at work tomorrow. If that doesn't work, I'll roll my own. Thanks for all of the great ideas.
 
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hornet driver

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If you cannot wait for a launch, then get some of the larger drinking straws and wrap them in masking tape so that they can be glued reliably.[/QUOTE]

This is important. Gluing the straws directly DOES NOT WORK! That said I've gone to aluminum tubing--sand the surface well and epoxy on!
 

manixFan

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Every Ace hardware has a small display stand with sheet brass and tubing. It will often also have the aluminum tubing. Michael's and Hobby Lobby also have the tubing mentioned by others. Lowe's may even have some. Just scuff it up where you are going to glue it.

If you roll your own use a mandrel that is slightly oversized if possible, not the launch rod. (or wrap it in a a couple of layers of wax paper first.) You want a loose enough fit so it won't bind if the rod is dirty from prior launches or has any surface roughness. For a scout project we tried making our lugs and found out the hard way about using a launch rod as a mandrel


Tony
 

Howie

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Here's another option for you: make hoop lugs with a paperclip or two. I discovered this on Apogee Components' website, and I like this for semi-scale rockets as they look less imposing then a launch lug. To do this, take a large paper clip and find the bend that slips around your rod - probably the big one for a 1/4" rod. Holding that bend at the top, cut both lengths off about 3/4" down, then bend them toward or away from you at a 90 degree angle about halfway up the remaining length. Drill two holes side by side on the body tube, insert the ends straight end, and stand it up so the part from the bend outward is perpendicular to the length of the rocket and those ends are now pressed along the inside of the body tube. Slip your rod through this dry-fitted hoop, and if the rail slides smoothly without excess slack, glue it down. Repeat the same procedure several inches above or below the first and you're set.
 
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