? About a launch lug that sticks

[LaunchPad]

So I've put together and painted this rocket that is ready to launch.

https://www.acsupplyco.com/estes/estes_superneonxl.htm

The launch lug is placed between the gap of two of the bottom outside tubes. It sits right above them. So the rod goes through the gap and then the lug.
When putting the launch rod into it, I noticed that it sticks just a little bit. It's not as smooth as it is on a rocket, like the Alpha.
In comparison, when I hold the Neon vertically with the rod, it doesn't slide down but with an Alpha it does.

So my questions are if this will be a problem at all during launch?
Is there a non-flammable substance I could grease the rod with or inside the launch lug?

 

[Gary Byrum]

Make sure your lug is cleaned out. Sometimes primer and or paint can get in there and cause it to be tight. I make sanding rods from wooden dowels for a number of things including sanding the inside of lugs.

 

[LaunchPad]

Make sure your lug is cleaned out. Sometimes primer and or paint can get in there and cause it to be tight. I make sanding rods from wooden dowels for a number of things including sanding the inside of lugs.

So I wrap sand paper around a dowel and run it through?
Its pretty tight in there as it is.

 

[Gary Byrum]

I glue my sandpaper on the dowel. Usually 3-4" long and just wide enough to overlap just a bit. They get lots of uses before I have to make replacements. You have the be patient making them, so one good starter is to pre-roll your paper around the dowel to curl it. Apply glue and carefully roll the dowel over the paper picking it up on the other side to keep rolling. It will want to come loose if you don't help it along. Once you get it around the dowel, keep rolling in that same direction over and over (wiping excess glue off in the process) to get out any excess glue and air bubbles. Clamp with clothespins till dry. Use a dowel about 1/2 the thickness of the lug because the sandpaper will about be just enough to fit properly. If all this seems like too much, use a rat tail file.

 

[les]

Also. have you checked the alignment of the lug to the gap? If it is off that could cause some binding

 

[LaunchPad]

Also. have you checked the alignment of the lug to the gap? If it is off that could cause some binding

Yes I did by peering through one end and seeing that it may have been off a tick.
So I removed the lug, repositioned it and it still sticks.

 

[Gary Byrum]

Yes I did by peering through one end and seeing that it may have been off a tick.
So I removed the lug, repositioned it and it still sticks.

So here's all I can offer at this point. If you're sure the lug is cleaned out and the rod is cleaned off, check in various directions to see if your rod slips through the lug easily. You should be able to slide the rod in with no friction. If you have friction, go to a larger lug. Since we don't have a clue, .....how long is that lug, and how tall is that rocket. THIS CAN MATTER! If the lug is low and the rocket is tall, you may not have a balance going on. That can cause the rod to bind in the lug. Good rule of thumb here, If your rocket is 14" or taller, you may need 2 lugs. If it's shorter, use one longer than average lug.

 

[Bat-mite]

Is the BT perfecty straight? Try putting a level on it. Even a 1/32" difference could cause a problem. If all else fails, like Gary said, bump up to a 1/4" lug.

 

[KenECoyote]

Always keep a launch rod of the same size or a section of metal rod of the same diameter to use for aligning launch lugs when gluing them. Eyeballing may look good, but it's fairly imprecise and can lead to binding once on the rod. Additionally, some rods get dirt or rust on them, so you should keep a small pad of sandpaper in your pocket for when you put your rocket on the pad.

Assuming the launch rod is straight...

If the lug itself has stuff in it (paint, glue, etc.), you can use a drill bit of the same size (ex. use 1/8" drill for 1/8" rod) and push it through or ream it out with finger pressure You can also start with a smaller drill bit first if the right size is too tight. Alternatively, use metal tubing of the same size and you can sharpen the edge and twist/push it through.

If all else fails (including "adjusting" the bottom spacing if possible), I'd agree with the earlier suggestion of replacing the upper lug with a larger one. A little binding is okay, but you have to make sure it isn't too much and that it won't take the rod with it. If unsure, err on the side of caution and remove the rocket from the rod for adjustment.

Good luck and post some pics!

 

[Bat-mite]

If all else fails (including "adjusting" the bottom spacing if possible), I'd agree with the earlier suggestion of replacing the upper lug with a larger one. A little binding is okay, but you have to make sure it isn't too much and that it won't take the rod with it.

Or rip the lugs off at launch.

 

[Gary Byrum]

Here's something else to keep in mind. I have all three sizes of rods used for rocketry, but mostly invest in 3/16" & 1/4" lugs. All of my lugs fit my rods perfectly and each rod is the precise width according to my calipers. When I go to the launches, I am discovering that the rods they have are usually too thick. Even though I clean them off. I rarely ever find one that fits my 1/4" lugs well at all. I wind up using a thinner rod almost every time. The bottom line here is (from my perspective) build with a lug larger than you need especially if you attend club launches. I need to pack my calipers for this weekends event and just see for myself and show these clubs that their rods are too thick.

 

[LaunchPad]

So here's all I can offer at this point. If you're sure the lug is cleaned out and the rod is cleaned off, check in various directions to see if your rod slips through the lug easily. You should be able to slide the rod in with no friction. If you have friction, go to a larger lug. Since we don't have a clue, .....how long is that lug, and how tall is that rocket. THIS CAN MATTER! If the lug is low and the rocket is tall, you may not have a balance going on. That can cause the rod to bind in the lug. Good rule of thumb here, If your rocket is 14" or taller, you may need 2 lugs. If it's shorter, use one longer than average lug.

OK so first I gotta try and clean out the lug using your idea of a dowel wrapped in sandpaper or the other one with a drill bit and/or cleaning off the rod.
First I gotta get to the local hardware store to buy a dowel that fits.

If I need to get a bigger lug, then where do I get one?
I think the hardware store may sell hollow metal tubes. Is that what I would use?

Though I would think that everything I got should work just fine since it is provided by Estes and they are the rocket scientists who know this stuff.

One thing at a time though. First I'll clean everything and let you know how it went and then take the next suggested steps.

 

[LaunchPad]

Here's something else to keep in mind. I have all three sizes of rods used for rocketry, but mostly invest in 3/16" & 1/4" lugs. All of my lugs fit my rods perfectly and each rod is the precise width according to my calipers. When I go to the launches, I am discovering that the rods they have are usually too thick. Even though I clean them off. I rarely ever find one that fits my 1/4" lugs well at all. I wind up using a thinner rod almost every time. The bottom line here is (from my perspective) build with a lug larger than you need especially if you attend club launches. I need to pack my calipers for this weekends event and just see for myself and show these clubs that their rods are too thick.

If I need this advice it would just be for the one rocket since that is the only one that I'm having this issue with and don't plan to get any more rockets ever again or any time soon. I have 10 and I think that is enough for now!

I appreciate all the advice you and others have given me and will keep it all in mind and try what is being suggested.

I'll post updates and pics later on.

 

[KenECoyote]

If I need to get a bigger lug, then where do I get one?

You can get lugs from Estes or ask an experienced rocketeer and they should have plenty. Alternatively, you may be able to find something of the same size to use if you can't salvage the one you have.

I took a look at the specs and it noted "Requires Estes Max Launch Rod #2244", which is a 3/16" rod. I think I have a heavy paper straw I got from some restaurant recently that looks to be the same; however if I use that, I would coat the outside with CA or wood glue to strengthen it and would add glue fillets to the sides.

If all else fails and you're in a bind, PM me your address and I'll mail you a couple.

 

[Gary Byrum]

OK so first I gotta try and clean out the lug using your idea of a dowel wrapped in sandpaper or the other one with a drill bit and/or cleaning off the rod. If I need to get a bigger lug, then where do I get one?
Though I would think that everything I got should work just fine since it is provided by Estes and they are the rocket scientists who know this

So, this is a kit, and I take it, you don't usually keep a supply of misc. parts around your house/shop, right? I am a scratch builder/designer, so I keep a lot of extra parts and supplies around all the time. Easy for me to just grab another lug. For you, you would have to order your stuff or go to a hobby store that supplies extra things besides kits. I get most of my supplies from BRS HOBBIES. Brian has recently seen to it that he keeps his rocketry stock up to par and he also has better pricing than most online companies. Also really fair shipping prices too.

Let's hope you won't have to go this far just to fix a tight lug though. At least you're in the right place for the help you need. I too, have also wondered why my lugs in the past did what yours was doing and never realized they were gunked up. Sealers, spray primers, base coats, final painting (most anything coming from rattle cans) are the perfect culprits in gunked up lugs. If you clean it out carefully and try not to over do it, you may get the results you are looking for. Been there, done it.

 

[samb]

So I've put together and painted this rocket that is ready to launch.

https://www.acsupplyco.com/estes/estes_superneonxl.htm

The launch lug is placed between the gap of two of the bottom outside tubes. It sits right above them. So the rod goes through the gap and then the lug.
When putting the launch rod into it, I noticed that it sticks just a little bit. It's not as smooth as it is on a rocket, like the Alpha.
In comparison, when I hold the Neon vertically with the rod, it doesn't slide down but with an Alpha it does.

So my questions are if this will be a problem at all during launch?
Is there a non-flammable substance I could grease the rod with or inside the launch lug?

For this rocket, the launch rod runs up through a gap in the tube fins (about 6 inches in length ?) before engaging the launch lug.



I would suggest that glue and/or paint in that gap is causing the additional friction you are describing. So that area may need some attention with some dowel-attached sandpaper as well. The launch lug for this model is 3/16 correct ? I have seen successful launches from a 5 foot long 1/8 inch rod but, that said, I would work on it a little first because that size rocket benefits from the stiffer 3/16 rod.

I have always kept my launch rods dry and clean with 600 grit sandpaper before, during, and after use. Others may have experience with lubricants. Hope this helps.

 

[LaunchPad]

You can get lugs from Estes or ask an experienced rocketeer and they should have plenty. Alternatively, you may be able to find something of the same size to use if you can't salvage the one you have.

I took a look at the specs and it noted "Requires Estes Max Launch Rod #2244", which is a 3/16" rod. I think I have a heavy paper straw I got from some restaurant recently that looks to be the same; however if I use that, I would coat the outside with CA or wood glue to strengthen it and would add glue fillets to the sides.

If all else fails and you're in a bind, PM me your address and I'll mail you a couple.

Yeah, from looking over the launch rod instructions, it does look like it's the 3/16th one.
I got my gear more than 30 years ago and it looks like they changed the model number for the rod. Mine is listed as 87080. Curious they would do that.

Thank you for your offer. I'll consider it after trying other options and if I can't find anything here.
Question though; Would a normal diameter size drinking straw cut down to the same length work? Or does the lug need to be snug?

 

[LaunchPad]

For this rocket, the launch rod runs up through a gap in the tube fins (about 6 inches in length ?) before engaging the launch lug.

View attachment 293342

I would suggest that glue and/or paint in that gap is causing the additional friction you are describing. So that area may need some attention with some dowel-attached sandpaper as well. The launch lug for this model is 3/16 correct ? I have seen successful launches from a 5 foot long 1/8 inch rod but, that said, I would work on it a little first because that size rocket benefits from the stiffer 3/16 rod.

I have always kept my launch rods dry and clean with 600 grit sandpaper before, during, and after use. Others may have experience with lubricants. Hope this helps.

Yes, it does help.
I'll add 600 grit sandpaper to my list for the trip to the hardware store when I get the smaller dowel for cleaning.
And I appreciate the tip for cleaning in between the tube fins.

 

[KenECoyote]

Yeah, from looking over the launch rod instructions, it does look like it's the 3/16th one.
I got my gear more than 30 years ago and it looks like they changed the model number for the rod. Mine is listed as 87080. Curious they would do that.

Thank you for your offer. I'll consider it after trying other options and if I can't find anything here.
Question though; Would a normal diameter size drinking straw cut down to the same length work? Or does the lug need to be snug?

Okay, time for some important info...I either forgot this or never paid it mind, but the "3/16"/5mm launch rod" Estes has is apparently not 3/16"/5mm. I believe it is termed that way since it is meant to be the rod for 3/16"/5mm launch lugs. I just measured one of the lugs and the hole in the middle is 3/16"/5mm, then I put the rod into it and there's just under 1mm of slack (which answers your question of snug or loose...loose!). So the '3/16" rod' I have (which I pulled out of an Estes Eliminator XL launch set), is actually 4mm (~5/32").

Maybe I have the wrong stuff here somehow, but someone please correct me if I'm mistaken. I've never bothered to measure, so this wasn't noticed. Also this would explain why some club rods seem to bind...they may actually be using 3/16"/etc. rods.

LaunchPad - Can you measure the hole in the middle of the upper lug just to confirm?

 

[Gary Byrum]

Maybe I have the wrong stuff here somehow, but someone please correct me if I'm mistaken. I've never bothered to measure, so this wasn't noticed. Also this would explain why some club rods seem to bind...they may actually be using 3/16"/etc. rods.

I use 2 basic sizes 3/16" & 1/4" made by Sunward. Why they fit nicely on MY rods of the same width, is a bit of a mystery to me. You'd think they would be tight, but they aren't. Usually the 1/8" rods at the launches are OK to use with no issues. But the 3/16 & 1/4 " rods are tight. In fact, they won't even go on the rods at all. Makes me wonder what everyone else is using. I'm definitely taking those calipers with me this weekend.

 

[neil_w]

...don't plan to get any more rockets ever again or any time soon. I have 10 and I think that is enough for now!

:roll:

You owe me a new keyboard.

Anyway, another good lug cleaner-outer is a round jeweler's file, just be gentle.

 

[LaunchPad]

Okay, time for some important info...I either forgot this or never paid it mind, but the "3/16"/5mm launch rod" Estes has is apparently not 3/16"/5mm. I believe it is termed that way since it is meant to be the rod for 3/16"/5mm launch lugs. I just measured one of the lugs and the hole in the middle is 3/16"/5mm, then I put the rod into it and there's just under 1mm of slack (which answers your question of snug or loose...loose!). So the '3/16" rod' I have (which I pulled out of an Estes Eliminator XL launch set), is actually 4mm (~5/32").

Maybe I have the wrong stuff here somehow, but someone please correct me if I'm mistaken. I've never bothered to measure, so this wasn't noticed. Also this would explain why some club rods seem to bind...they may actually be using 3/16"/etc. rods.

LaunchPad - Can you measure the hole in the middle of the upper lug just to confirm?

It would make sense that the rod and lug are not going to be same measurements.

The lug I have on the rocket I'm having an issue with, I'm sure it's the normal size as on all my others. Such as the Alphas.
If you still want me to measure, I suppose I could. How do I do that?

I did a test. While holding the rod in one hand I put the rocket on upside down or the rod through the top of the lug and the rocket was able to slide easily. So the problem is in between the launch tubes and not in the lug itself.

 

[KenECoyote]

It would make sense that the rod and lug are not going to be same measurements.

The lug I have on the rocket I'm having an issue with, I'm sure it's the normal size as on all my others. Such as the Alphas.
If you still want me to measure, I suppose I could. How do I do that?

I did a test. While holding the rod in one hand I put the rocket on upside down or the rod through the top of the lug and the rocket was able to slide easily. So the problem is in between the launch tubes and not in the lug itself.

Correct that the lug and the rod wouldn't necessarily be the same dimensions (unless it's meant to be a flush fit, which would cause binding). However I think there is confusion over Estes's naming...they're calling it a 3/16" rod, when it's not and it's just the rod meant for a 3/16" lug. Just use any standard ruler and measure the diameter of the hole in the lug...should be either 3/16" or 5mm (if I'm not mistaken). If the upper lug is good and smooth, then either it's the bottom insertion area or the alignment between the two areas.

Another trick for finding out where something is binding is to coat a launch rod with a black Sharpie, run it through a few back and forth passes and you'll see black where it is binding. If you don't want to mark up your rocket, you can just try running the rod unmarked more times and look for rub marks.

 

[jeff_j_black]

...don't plan to get any more rockets ever again or any time soon. I have 10 and I think that is enough for now!

OK this thread just got really weird!

 

[LaunchPad]

OK this thread just got really weird!

I dunno why that comment got the attention that it did.

I guess I don't have as many rockets as the average poster on here?

 

[KenECoyote]

I dunno why that comment got the attention that it did.

I guess I don't have as many rockets as the average poster on here?

Just to give you a glimpse of the spiraling madness that is rocketry...this was recently posted on the scratchbuilding forum:

OK here goes the build. First you need a clean and organized work area clear of other projects, clutter and trash. A good solid cutting area and grid matt would be nice.

View attachment 292774
Well, I think I fall a bit short of the ideal.

Rocket Hell to some (like my wife), Rocket Heaven to others (like me).

 

[Gary Byrum]

I dunno why that comment got the attention that it did.

I guess I don't have as many rockets as the average poster on here?

Let put it to you like this. Your 1st 10 rockets are likely to lead toward your next 40. Rocketry is an addiction to a great many. Life gets in the way when you're younger and you may shove it in the closet for some years. But sooner or later, that Rocket Bug is going to bite you again and you'll be a BAR.(born again rocketeer)

 

[KenECoyote]

Don't mean to scare you...it's just that the big majority here find it so fun, engaging and cool that it can be addictive...but in a good way.

 

[KenECoyote]

If you still want me to measure, I suppose I could. How do I do that?

Here's a pic of my measuring a 3/16" lug, a pic of the "3/16 rod" inside the lug and my bag of spare lugs (some are inside others and I have yet another bag ):

 

[Micromeister]

I've found recently that many of the supplied lugs (all Sizes) 1/8", 3/16" & 1/4" have been running a bit on the small size.
Add to this the 2 to 5% rolling varience in Steel and Stainless Steel rods there can be a bit of a tight problem.

As Gary mentioned sand paper round dowels are a fine way to increase the ID of a sticky lug,
That said however, I'm more inclined to believe the forward lug is slightly mis-aligned with the pass through tubing. No amount of sanding will fix this problem.

You do have a couple options.
#One is to cut the forward Lug down to just a small 1/4" or 3/8" long segment. This won't hurt the model flying but could correct the mis-alignment problem by shortening the length of lug the rod must travers. #2 would be to completely remove the lug and reattach it using a Launch Rod of the proper size to ensure the lug and Tube seam slot are really in alignment. By having 12- 18" sections of all the rods I might use, I can attach Launch lugs with precision & piece of mind.

Some time back I purchased a bunch of 1/8" x 4" Launch Lugs for stock. At the time I though the price was good and they "Looked" just fine. However after installing the very first one from the batch I noticed it was very tight on our standard 1/8" Stainless Steel 316 Cold Rolled Launch rods. After closer inspection I found the entire batch was under sized by .010" just enough to make the rods bind. As these were purchased on sale they were not returnable. I have two choices #1 junk the entire batch (100pcs) and buy more. or #2 Only use these lugs as tiny dual Lugs 1- 3/16" long at the rear of the model and a second 1/8" long just behind the CG of the model. I've been doing this ever since with no binding problem at all as long as the two piece are set using a section of standard 1/8" STAINLESS Launch rod.