Securing small pieces of pe

[mozart]

I’d value the thoughts of you all regarding fixing small, and I’m talking 2mm or thereabouts, pieces of photo etch to a plastic wing.  The pe represents brackets on a Tiger Moth’s wing to which rigging lines are attached. I’m intending using Prym elastic for the rigging so there will be a bit of tension, hence the pe must be really secure.

The options I guess are CA, epoxy, UV or pva-based glues. Any advice very welcome.

Edited January 18, 2023 by mozart

[Juggernut]

CA, at least in my experience, is strong in tension but very weak in shear loads.  Using that as a guide and knowing that the rigging will probably have both types of load associated with it, I'd use a fast dry (5 minute), two part epoxy with suitably roughed up PE and wing contact surfaces to give the epoxy something to really grip to.  I haven't tried any UV types of glue. I doubt you'd want PVA but one of the guys in our club swears by Acrylic Gel medium (yes, the art based stuff).  He says it takes a couple hours to cure (allowing time for movement/adjustment) but he says he needs pliers to pull off the PE once it's dry.  I think that may be a little bit of a tall-tale but I'm going to give it a shot at some point in the near future and see how well it really works.

 

You can always experiment with different glues (on a test fixture/model wing) and see which ones perform best for you. 

 

Just my two-cents worth.

[mozart]

Thank you, experimenting is definitely the way to go.  Epoxy is my favourite at the moment but we’ll see. 

[Out2gtcha]

When I glue PE parts that have to be secure (such as the wing gussets that actually support some structure inside the wheel wells on my Grumman Tigercat) I pretty much always use the same tried and true method.

1 - get the parts as clean and roughed up as possible, normally i like to use soft clay shapers to clean and a tiny bit of 1000 or 1200 grit paper on a sticky tool , but for the tiniest of the tiny, I normally just clean with 91% alcohol with a micro-brush. Usually I do this while still on the PE fret for stability, then clean edges afterword.

2 - mix up a small batch of JB Weld and dip the tiny part in the JBW with a sticky "stix" or if the part is really dinky I normally just use micro tweezers or the like to get a bit of the JBW on the back and set it in place

[quang]

What you need in those cases is two apparently contradictory features:

1- a LONG delay time to permit a precise location of the item

2- a VERY SHORT time to ‘freeze’ the item once it’s done

For this, I think there’s no better solution than UV-cured glue which allows indefinite time to adjust the item and literally seconds to secure the glued bond by flashing the blue light.

It works for me. Of course YMMV. 
Cheers,

Quang

[mozart]

I KNEW you’d recommend UV Quang, I know you’re a fan. The jury’s still out but I like your reasoning. 

[Bob MDC]

You could try epoxy putty it's self-filling and can be sanded with a fibre glass pencil, I've used this on a couple of pattern jobs.

Can be a bit slow curing but plenty time to position.

 

Bob

[mozart]

14 hours ago, Out2gtcha said:

When I glue PE parts that have to be secure (such as the wing gussets that actually support some structure inside the wheel wells on my Grumman Tigercat) I pretty much always use the same tried and true method.

1 - get the parts as clean and roughed up as possible, normally i like to use soft clay shapers to clean and a tiny bit of 1000 or 1200 grit paper on a sticky tool , but for the tiniest of the tiny, I normally just clean with 91% alcohol with a micro-brush. Usually I do this while still on the PE fret for stability, then clean edges afterword.

2 - mix up a small batch of JB Weld and dip the tiny part in the JBW with a sticky "stix" or if the part is really dinky I normally just use micro tweezers or the like to get a bit of the JBW on the back and set it in place

Thanks Brian, that sounds very thorough and worth a try! 
 

10 hours ago, Bob MDC said:

You could try epoxy putty it's self-filling and can be sanded with a fibre glass pencil, I've used this on a couple of pattern jobs.

Can be a bit slow curing but plenty time to position.

 

Bob

Hmmm, that’s a completely new one to me Bob, thanks for the info, must investigate! 

[ade rowlands]

Maybe give one of the Black ‘rubberised’ Super Glues a try. You get the strength of a super glue but the rubber component might provide the ‘give’ you will need when tension is added when rigging.

[PlamoSnep]

The rule of securing small PE pieces is that if it's not where you want it, it will stick instantly, and if it is where you want it, it won't stick at all.

 

I usually use Mercury Adhesives CA and don't have any issues.  If you're worried about strength, epoxy would be the way to go, but you would have to hold the part in place for 5 mins or longer.  Another option would be G&S Hypo Cement.  I use it mostly for clear parts (though it can craze clear parts if you get it on them) as it's much stronger than white glue.  It is a bit of a pain to use as it wants to string everywhere.

[chukw]

I love soldering, so I add a pin to tiny bits, drill and glue. Here's an exclusive preview to the Mohawk post I hope to get on line tomorrow. The upended wooden block is my old mini Miter Jr.- any small u-channel with a section to tape the wire securely to will do.  You saw it here first!

[mozart]

Thank you for all of your comments, advice and thoughts chaps, all very much appreciated.  So after about 36 hours after setting things up, all the glues have passed the "pull" test with a short piece of elastic attached, which I'm pleased and in some cases slightly surprised about.

 

So I suppose the next decision is which to use, and for ease and accuracy either thin CA or UV wins.  My only concern with the CA is that sometimes there is a slight "blooming" or greyish-frosty area around the CA as if it's reacting with the paint, so UV does it for me.

[Out2gtcha]

3 minutes ago, mozart said:

My only concern with the CA is that sometimes there is a slight "blooming" or greyish-frosty area around the CA as if it's reacting with the paint, so UV does it for me.

 

 

Honest question here on the UV (of which I use all the time now for other projects), when you have super dinky PE parts to glue that are flat sometimes and cannot have a lot of glue on the back of them, and you dont want any glue around the edges/showing how does the light cure the UV in that case?

[mozart]

25 minutes ago, Out2gtcha said:

 

 

Honest question here on the UV (of which I use all the time now for other projects), when you have super dinky PE parts to glue that are flat sometimes and cannot have a lot of glue on the back of them, and you dont want any glue around the edges/showing how does the light cure the UV in that case?

Honest answer Brian, and I fully understand the logic of your question, is I don’t know but it does! 

[PlamoSnep]

5 hours ago, chukw said:

I love soldering, so I add a pin to tiny bits, drill and glue. Here's an exclusive preview to the Mohawk post I hope to get on line tomorrow. The upended wooden block is my old mini Miter Jr.- any small u-channel with a section to tape the wire securely to will do.  You saw it here first!

Soldering scares me, but it's definitely something I have to learn for some of the armor PE sets I have.  Do you have any recommendations for soldering kits/irons for starters?