Repairing TY - H Arm

[KEITH KUHN]

I wonder has anyone tried to cement or glue
the plastic motor head to
the carbon fiber arm ?
It slips on fine, it just needs to be cemented.
The little plastic rivet broke away. Any recommendations ?
Thanks
Keith Kuhn

 

[georgero]

Yes, superglue it will work . Make sure you put it in the same position. If you change the position slightly you will have problems. Just align both holes and you will be fine.

 

[jannislh]

Do not forget to sand the carbon fiber tube. It is very smooth and no glue will stick to it as good as it could. Just roughen the surface and it will work fine.

 

[Mrgs1]

I wonder if solvent weld glue would be better than super glue?

 

[KEITH KUHN]

Yes, superglue it will work . Make sure you put it in the same position. If you change the position slightly you will have problems. Just align both holes and you will be fine.

Thanks I will give super glue a try.
Keith Kuhn

Yes, superglue it will work . Make sure you put it in the same position. If you change the position slightly you will have problems. Just align both holes and you will be fine.

 

[jannislh]

I wonder if solvent weld glue would be better than super glue?

It will not work. The epoxy resin used for making carbon fibre is not soluble in most substances and will therefore not work with solvent weld glue. In fact there are some solvets which are cappable of dissolving (or at least of softening it) but it will not be enough to create a durable weld.

I am not sure about the engine mount. I think it will either be ABS or some sort of polamides. ABS would work. Polyamides most certainly not.

A low viscosity super glue is in my opinion the best choice for glueing together the parts.

 

[davemh]

What about just putting new rivets in it.
Just asking, haven't needed to repair one, yet.

 

[Mrgs1]

It will not work. The epoxy resin used for making carbon fibre is not soluble in most substances and will therefore not work with solvent weld glue. In fact there are some solvets which are cappable of dissolving (or at least of softening it) but it will not be enough to create a durable weld.

I am not sure about the engine mount. I think it will either be ABS or some sort of polamides. ABS would work. Polyamides most certainly not.

A low viscosity super glue is in my opinion the best choice for glueing together the parts.

https://www.easycomposites.co.uk/#!/resin-gel-silicone-adhesive/structural-adhesives/vm100-black-methyl-methacrylate-adhesive.html

 

[KEITH KUHN]

It will not work. The epoxy resin used for making carbon fibre is not soluble in most substances and will therefore not work with solvent weld glue. In fact there are some solvets which are cappable of dissolving (or at least of softening it) but it will not be enough to create a durable weld.

I am not sure about the engine mount. I think it will either be ABS or some sort of polamides. ABS would work. Polyamides most certainly not.

A low viscosity super glue is in my opinion the best choice for glueing together the parts.

Thanks I will go with the super glue.
After that I may add a dab
Of hot glue where the 2 meet on the outside.
Before I launch all will be tested
Keith Kuhn

 

[DCH]

What about just putting new rivets in it.
Just asking, haven't needed to repair one, yet.

The pop rivets are plastic and not very common in that small size. An aluminium or steel pop rivet would require too much force to set and most likely crack the carbon fiber and the ABS motor pod. Super glue is the best option unless you can find a plastic pop rivet.

 

[KEITH KUHN]

The pop rivets are plastic and not very common in that small size. An aluminium or steel pop rivet would require too much force to set and most likely crack the carbon fiber and the ABS motor pod. Super glue is the best option unless you can find a plastic pop rivet.

I will go with the Super Glue
Thanks

 

[PatR]

If trying to bond plastic to carbon fiber, super glue isn’t going to hold very long. Standard super glue and carbon fiber is a match made in Heaven, but bonding to plastics requires a very special formula of super glue.

As a PSA type thing, if we had a broken CF boom we would not want to simply “but glue” the two ends together and expect it to hold. What we would do is but glue (one T in “but” used to fool the auto censor) the two ends, then roughen the boom on both sides of the break to break the gloss surface, clean the surface with rubbing alcohol, and wrap a strip of carbon or fiberglass cloth around the boom, with the cloth extending at least 3/8” past each side of the break and bond it with super glue or epoxy.

If just the rivet is broken I might consider removing the motor and wires and drill the smallest hole that would allow a thin bolt to pass through both sides of the boom/ motor mount and lightly secure the bolt with a nylock nut. Avoid compressing the boom with the nut.

 

[KEITH KUHN]

If trying to bond plastic to carbon fiber, super glue isn’t going to hold very long. Standard super glue and carbon fiber is a match made in Heaven, but bonding to plastics requires a very special formula of super glue.

As a PSA type thing, if we had a broken CF boom we would not want to simply “but glue” the two ends together and expect it to hold. What we would do is but glue (one T in “but” used to fool the auto censor) the two ends, then roughen the boom on both sides of the break to break the gloss surface, clean the surface with rubbing alcohol, and wrap a strip of carbon or fiberglass cloth around the boom, with the cloth extending at least 3/8” past each side of the break and bond it with super glue or epoxy.

If just the rivet is broken I might consider removing the motor and wires and drill the smallest hole that would allow a thin bolt to pass through both sides of the boom/ motor mount and lightly secure the bolt with a nylock nut. Avoid compressing the boom with the nut.

What you are saying is very interesting.

The motor head came free from the carbon fiber arm (no breaks) slip it on straight and glue it. The little plastic rivet gave way.
Then see if it holds.
Any further advice is appreciated
Keith

Do not forget to sand the carbon fiber tube. It is very smooth and no glue will stick to it as good as it could. Just roughen the surface and it will work fine.

Thanks I will do that.
Keith