JB Weld on control arms?
 

My new plane calls for metal clevises to be soldered to the push rod - can I use JB Weld instead? I don't have a soldering iron or a way to thread the 4-40 rod, but do have some JB Weld in my toolbox.

Thanks.

RE: JB Weld on control arms?
 

Solder clevis' are not threaded.
They slip onto the unthreaded control rod and then you wick solder into them.
I wouldn't trust JB weld for this app.
You can get a cheap soldering iron for around $10

RE: JB Weld on control arms?
 

I wouldn't use it. With the JB weld you are only going to get a little bit at the end of the clevis attaching it to the control rod. When you properly solder a clevis on to a pushrod the solder will flow down inside the clevis giving a solid and strong joint. The saying "The proper tool for the proper job" comes in to play here. JB weld isn't the proper tool for making up solder clevises. You can pick up a soldering iron for ~$10-$12 at Lowe's or your local Radio Shack. Just make sure you practice making the solder joints before you actually try to solder the actual clevis on to the pushrod.

If you don't have a soldering iron I would go to the LHS and purchase some threaded pushrods and clevises. As an FYI, you can't cut threads in a push rod yourself. The pushrods that you purchase actually have the threads cold rolled into them, so the threads are actually wider than the pushrods themself. If you cut threads into the rod you will find that the clevis won't fit the threads

Ken

RE: JB Weld on control arms?
 

Ok, thanks guys. I'll see when they get here if I can get matching size threaded (at both end) rods, if not I'll get a soldering iron. I'm just bad at soldering so have avoided it at all costs over the years. Of course this is different than soldering wires together, but by how much I don't know.

RE: JB Weld on control arms?
 

This is one of the not terribly difficult jobs that are perfect for learning soldering that are so useful further down the line and there are so many things you can use the skill for in modeling.

John

RE: JB Weld on control arms?
 

You astound me. Here is a guy considering going into pattern competition perhaps with a very costly YS or OS engine as well as airplane but does not have basic tools. By the way pushrod threads for most 60 or lesser size aircraft are 2/56 not 4/40. Young man think you should slow down quite a bit practise, practise, practise, learn,learn,learn. You have been way over your head in many areas.
just my advise from an OLD FART.

RE: JB Weld on control arms?
 

DON'T buy a cheap soldering iron. Spend the money and get a decent one. You won't regret it, believe me on this!

RE: JB Weld on control arms?
 

Soldering isn't any guarantee either, if it isn't done right. Radio Shack sells a big 'ole iron that will provide enough heat for 50/50 solder......but the best way to go is with a silver solder kit and propane torch.
Soldering doesn't take much more skill than working the cash register at McDonalds if you can follow instructions.

RE: JB Weld on control arms?
 

I will tell you how to solder it.

Buy good soldering iron, not some cheap junk.

Put the rod into the clevis, heat the brass clevis with the soldering iron near the end where the rod enters, but not directly on the end.

After a few seconds test the area where the rod enters the clevis with the solder. When it gets hot enough the solder will wick into the clevis.

Once it does that remove heat and solder.

Solder only bonds when BOTH materials are heated.

Most cheap irons cool when they touch the material and that is what cause most ppl to think they can't solder. You need an iron that will stay hot.

You can do it!

RE: JB Weld on control arms?
 

Get a Bernzomatic propane torch, silver solder and soldering paste. Very useful if you ever solder landing gear, cabane struts, or control linkages. Silver solder is much stronger. Key to soldering is to clean everything and use plenty of soldering paste. Heat the work and allow the solder to wick into place.

Rod theaded on both ends is a bad idea, as it can unscrew on one end while screwing in on the other.

RE: JB Weld on control arms?
 

For large joints like this you will need a high wattage iron. Large joints will "sink" heat away from a small watt iron. For example, 15 watts is great for intricate circuit board work, but 8 AWG wire or a thick piece of metal will cool down the iron too much. This can make soldering impossible or create ripe conditions for a cold joint. Heat the work with the iron and touch the solder to the work, NOT the iron. It should wick right in if the joint is heated enough. The joint must be held still until the solder cools completely. If not, the joint will look dull and will be very brittle. I always inspect my joints with a magnifying glass before continuing.

RE: JB Weld on control arms?
 

I have a thread going in another forum and I'm making a list of tools I will need. I have thoroughly read the instruction manual (twice) for this plane, and the only thing requiring soldering is the control arms. I didn't say I wouldn't solder, but was asking simply if there was another way. Other than this step the plane goes together like just about every other arf I've seen. I have some basic tools and even some not so basic tools. I just don't have a soldering iron.

I have burned 2 gallons of fuel already this week practicing - it's what I do. I have one plane, and I would like another one; everyone who sees me fly says the Venus will fit me well. I even asked my (very honest) instructor today, and he said I should have another plane. I ask questions and take advice, though I may be a bit enthusiastic about this hobby, but I AM learning.

And I chose the OS 2 stroke, not as costly as the YS or OS four strokes.

RE: JB Weld on control arms?
 

The trouble with using threaded clevis on both ends of a pushrod even if you could find it in the exact length (unlikely) is you turn it into something opposite of a turnbuckle, rotate it and it will go deeper into one clevis and fall out of the other. Now when this is done the minimum precation should either be 2/56 or 4/40 lock nuts on both ends or CA in the threads of one of the clevis. This is a pain either way and the failure mode is usually by the owner himself when he makes adjustments and my unknowingly come close to unthreading one end.


That why your instructions suggest using solder clevis'. Solder Clevis has no threads as mentioned and fit the desired rod perfectly for soldering. Clevis with thread does not fit the rod well and must be drilled.

The major differeance between electrical soldering and soldering soft threaded rod ends is the solder type. For electrical wire you would only use rosin core solder. For pushrods acid core solder works well, Rosin core is very difficult to work with on pushrod wire ends and will be a waste of time. Make sure you use 'Acid Core' for this job. You could use Silver solder but that is very expensive and will require a much hotter iron or a torch.

John


Edit: Unless you Silver Solder (certainly not neccessary) Use only Acid Core solder, Rosin core, hardware store plain 60/40 will just about be impossible to work with.

RE: JB Weld on control arms?
 

Ok, thanks to the rest of you. I used to try soldering with my Grandfather's old soldering iron, which was dirty and probably low power. I understand how to solder (I can sweat a pipe with the best of 'em) but I think I had the weak-iron-syndrome where all the metal didn't get hot, only where the iron was directly touching. Didn't realize this would make such a difference, but now it seems pretty obvious.

RE: JB Weld on control arms?
 

Most of the guys here think JB Weld is a bad idea. If I were stuck and needed to do the job you describe I would use it........... I use JB weld on my 33% planes to connect the control rod between the upper and lower ailerons...it has never given me any problems.I also used it on the upper attachment points of the upper wings....same results. These big biplanes have many many hours on them and the JB weld has been fine.
My advise is use it if you feel confident that you can get enough material on the two parts to make a good bond. Rough up the surface real good with some emroy cloth to get a good bond. Then LEAVE I SIT FOR A DAY without touching it.

JB weld will seep into any small space that it is on..that is the reason to let it sit for 24 hours, to make sure it gets to all the small cracks and spots and to ensure a good fracture free bond.
I know there will be those out there that give me grief about this suggestion but that is just how it is... I use it on certain spots and it has always worked for me so I'm letting you know. In fact I just did my throttel rod on my RCS215 with the stuff, this is the third time I have used it on the throttel rods and never has one ever given me any problems due to a failure of the bond.


Make your own desicision though.

RE: JB Weld on control arms?
 

Go 4-40 or equivalent [1/8" dia.] for .32 engines on up, 2-56 [1/16" dia.] is too wimpy for much over .25 sized. I have had some .40 powered planes eventually wear out 4-40 hardware, gotta keep your eye on it.

RE: JB Weld on control arms?
 

Socal,
I'm going to have to agree with you, been using JB Weld on Central hobbies carbon fiber tube without incident for years.

I've also used it with threaded clevises for the solid end, I would trust that much more than CA. Just clean it good with alcohol and ruff up any smooth areas.

RE: JB Weld on control arms?
 

I've fixed all kinds of things with JB Weld - it's really amazing stuff.

RE: JB Weld on control arms?
 

I've used JB to make crank case pressure backplates and know one thing to be true......let it set totally undisturbed for at least one day, if not more. The only times it has failed me are when I let it set for awhile, then handled the part before it was totally cured.
I think you could deeply score the pushrod with a sharp pair of side cutters in a few spots to give the JB a real solid tooth.

RE: JB Weld on control arms?
 

When you need to solder on A clevis they also are NOT the nice little gold ones, they are the silver ones that sometimes come in the kit/ARF or you go into your LHS and buy them, they say solder clevis. I also use 60/40 or 40/60 solder most the time instead of the silver solder. I also have the silver though, it's cheap to have them all on hand.
I have A lot of little tricks for soldering but it's stuff I have learned soldering LG and struts for bipes.
I use A small iron for wire because I don't use extensions either, I lengthen my servo leads instead.
For things like LG, cabanes and push rods I use a tourch. The big one I picked up in A box of stuff I bought at auction, big surprise and works great!! The little silver tourch is used the most. Just ask any crack head where the nearest head shop is and you can find one. Or, if you want then maybe A trip to Harbor Freight would suit you better. I have found the flux to be very important, some just works better then others. The tin I'm showing has been the best all around to date. I figure one tin per life time.
There is A control rod in the photo too with A soldered end. By soldering the one clevis you have one solid fixed side and one you can adjust for those small trim movements without risking the clevis to come loose and change your set up.
I think John mentioned it but CLEAN is the key word. Roughen up that rod with sand paper and clean with alcohol!!
Good luck!!

RE: JB Weld on control arms?
 

I've done some surprising things with JB Weld but I won't go into them because they aren't RC related. Still, I would not trust it to hold the clevis on the wire. I use a small torch that takes butane lighter fluid. They are pretty inexpensive and places like Home Depot or Lowes. If you clean the wire good and use a little flux, the joints come out great.

RE: JB Weld on control arms?
 

The problem with glued joints anywhere is joint design. If a slip fit is too tight, there won't be any space left for a mass of glue to do its' thing. This is what makes the idea of using glue in control systems iffy. I use glue when making up carbon pushrods, solder just doesn't get 'er done then. ;)

RE: JB Weld on control arms?
 

Get a soldering gun, at least 100 watts. It will heat up fast, and stay hot. Soldering push rods will be not only easy, but very satisfying.

RE: JB Weld on control arms?
 

This may be out of the price range you are looking at, but it does work pretty well. I have been using mine for almost a year now. I can solider battery leads to servo wire with it. It is a good investment for when you need a soldering iron. To take up less room on the bench, I used double sided tape to put the holder on top of the base.


Get good solder and flux, do not use acid core flux, it will make a mess. Resign core only. Also get some silver solder, it is a lot stronger then lead and tin mixes.

http://www.harborfreight.com/cpi/cta...emnumber=96375


Dru.

RE: JB Weld on control arms?
 

I think the one thing that is necessary when soldering is to make sure the tip is clean and tinned. Use the tin at the tip to transfer the heat from the iron to the work. I always keep the iron on the work as I wick the solder in and then I let it cool near the end of wicking, just so that it doesn't stop wicking half-way through. I think most of what you need to do can be done with an inexpensive 45W iron and some 60/40.
Good luck,
Curtis