Piko kits and adhesives - problems

[OBBherr]

I would appreciate advice from the collective wisdom of the forum. I am trying to construct the Piko refinery loading dock item no. 62049. I am having a terrible time securing the handrails to the walkway frame as the Pola glue does not seem to take, and only makes a very superficial bond. This is a real problem as every time I try to secure the walkway itself (which clamps the handrails in place), I dislodge a handrail and have to reglue it.

By way of experiment I have tried gluing some of the surplus sprues togther with my preferred Pola cement, but also Piko's supplied UHU Plast - same unstaisfactory result.

Now I always believed that polysturene cements have a solvent effect on plastics, which allows the treated area to effectively melt, then harden to form a bond. I am open to correction on this as I'm an accountant not a chemist. I can see no sign of this melting effect on my test sprues, and even after being clamped tgther for the best part of a day they separate very easily, even after I have scraped a clean area to apply the cement. I have never experienced this problem before, including construction of the Piko passenger bridge which uses similar parts.

Does anyone have any experience to share, or comments on what the problem may be? All contributions appreciated.

 

[dunnyrail]

I have had lots of success with UHU Power. However this is not a fast setting glue so perhaps a super glue (good quality not the pound shop rubbish) may be the thing.

 

[OBBherr]

Just found the thread on "PIKO Fix vs UHU Glue" I'm goiung to try the leaving it under pressure for 18 hours and see what happens.

 

[phils2um]

Could it be the handrails are not actually polystyrene but some other more flexible plastic? Something that may be less susceptible to breakage?

 

[JimmyB]

For stubborn plastics I use Carr's Butanone, melts ABS.

 

[OBBherr]

I was wondering that as well. I'll fish out some sprues from a troublefree kit and see if they react differently. Thanks for the hint.

 

[OBBherr]

Thanks for the Butanone tip. More experimentaion required.

 

[maxi-model]

The problem is usually the colour "wash" applied during manufacturing to give some form of "weathered" look. This "wash" acts as a barrier to the normal solvent properties of your chosen polystyrene cement/solvent. You must scrape/abrade this "wash" away where any parts are supposed to join. Max

 

[OBBherr]

I've tested for that (the wash as a barrier) although the items in question seem to the eye be an unwashed grey plastic.

So I scraped both surfaces down and tested with Pola and UHU Plast. Same problem.

 

[Greg Elmassian]

Yep, here in the USA, I did find a thick-bodied ABS solvent type glue, used for large ABS conduit... that did the trick, industrial strength.

 

[JimmyB]

Yep, here in the USA, I did find a thick-bodied ABS solvent type glue, used for large ABS conduit... that did the trick, industrial strength.

We have a similar solvent for drains and sewer pipes, which is very good, but not for fine items.

 

[Greg Elmassian]

Yep, thick and messy, and note again, usually the sewer/drain pipes are black, and there is a black abs glue.

In this case (which I forgot to mention) I found a clear ABS glue but was still thick bodied, so would have to sort of "paint it on" from the inside where it won't show.

Not a perfect solution, but I had some very finicky plastics that just shrugged off the normal, watery MEK / styrene glues.

Greg

 

[Andrew Foster]

I've used Plastruct Plastic Weld which says on the bottle that it joins ABS, styrene, butyrate and acrylic to itself and each other. I can't vouch for all those, but so far, it has been good. They recommend holding the parts together and an overnight cure, as it doesn't develop full strength immediately.

 

[ColinK]

My go to glues for difficult materials are ‘Powerbond’ brand of superglue and Devcon epoxy resin. They are not plastic solvent glues though.