I'm having trouble with hobby cement.

[Plumcrazy Preston]

I use Testors in the bottle with brush applicator because it's clear liquid and not goopy like airplane glue in tubes. It eats paint on surfaces easily and sometimes it doesn't bond well with bare plastic parts even. I'm thinking about using Krazy Glue or a similar fast-bonding product for finicky small parts that are difficult to glue with Testors cement. I've tried scraping the paint off for applying Tetsors but still sometimes parts don't hold. 

 

The AMT Kenworth W-925 Tractor kit is especially difficult to glue together (many parts lack tabs and holes) and having to bond painted parts makes matters much worse. Right now I'm assembling the engine. Several cemented parts like the oil pan and the dipstick keep falling off even with bare plastic mating surfaces. The block was painted tan and the accessories are painted gloss black. Many parts don't have tabs that fit in holes but some do. Klazy Glue type adhesives should work well for tiny parts glued directly to paint or tiny parts where getting a good hold is difficult even in plastic-to-plastic contact. These would be small parts like engine accessories and small body trim components like the visor and mirrors. Naturally, my truck chassis is cemented together plastic-to-plastic. But Krazy Glue might work for stubborn parts that keep coming loose with Testors cement as the model is being built. 

 

Is there a tough-bonding adhesive for plastic kits that's also not messy? Epoxy is messy too. 

 

What do you think?  

Edited May 4, 2021 by Plumcrazy Preston

[NOBLNG]

Thin super glue (CA) will work on close fitting parts, but you will need an applicator like “glue looper”  or a home made one in order to apply very tiny amounts. I prefer medium CA as it is easier to apply tiny amounts and doesn’t set instantly like the thin stuff. Either will bond to paint, but the joint will only be as strong as the paint-to-plastic bond is. The best thing to do is get some .020” brass rod (or any tiny wire) and make pins to join all the finicky little parts before paint. Then you are not relying on the glue for the strength and it saves a world of grief during final assembly! 🤨

Edited May 4, 2021 by NOBLNG

[youpey]

I recently bought this. It reminds me of the model master glue that was in the triangle container. It might be the same glue. It has a thin metal tip that you can put small amounts of glue.  I like it better than the tamiya extra thin cement. It does take longer to set though. However I have made many mistakes with the tamiya glue that i dont with this.

https://www.megahobby.com/products/25g-professional-liquid-cement-w-applicator-revell-germany.html

 

EDIT:

hmm, i am finding the glue doesnt hold as good as the model master. i have switched back

Edited May 6, 2021 by youpey

[NOBLNG]

36 minutes ago, Plumcrazy Preston said:

Several cemented parts like the oil pan and the dipstick keep falling off even with bare plastic mating surfaces.

I’m not familiar with this kit, but I imagine the oil pan should have large flat mating surfaces. So if it is falling off, perhaps your glue has gone bad? If the lid was left off, maybe the solvents evaporated?

[slusher]

on painted parts I use Loctite and apply wit a tooth pick. Dries and holds fast…

[Dave Van]

I have gone to Flex-i-file glue after Ambroid went out of biz.

[youpey]

26 minutes ago, slusher said:

on painted parts I use Loctite and apply wit a tooth pick. Dries and holds fast…

The red locktite? I never thought of this. Its such a great idea

[slusher]

I used that and now buy the bodes in blue off eBay that’s stronger..

[yh70]

get u some Ca glue (super glue) and a kicker for instant set of the glue. i use thick and medium but do keep thin on hand. also get u some de-bounder and extra glue tips..u can find this all on ebay. i been getting it their for years... i also use a liquid glue (orange bottle is the best) made by plastruct. it can also be found on ebay or Amazon .i been using these glues for many years. they is nothing no better. and it does not have to be a name brand of GA glue to work better than others brands..

Edited May 4, 2021 by yh70

[69_Stingray]

With the superglue, get you some debonder. Your going to glue your fingers together and need some to unstick them.  

[BubbaBrown]

B4 paint Same Stuff from Micro Mark, after Loctite Ultra gel control. Some times 5 min or 30 min epoxy.

 

[kurth]

The testors liquid cement is not working for bare plastic to bare plastic? That is very strange.  How old is this bottle? That glue works by application to both parts which are to be bonded, and it is pretty slow to set, so are you giving it enough time to set?  

[peteski]

Testors liquid cement is pretty much all-solvent (MEK). There is no way age or evaporation would weaken it. If it was to evaporate, there would be no liquid left in the bottles (well maybe some residue left, but not enough to use it.

I almost never glue painted parts. If I really have to use CA glue and BSI brand accelerator (because it is mild and doesn't attach paint like other accelerators).  But other than that, I make sure I glue bare plastic parts.  I use plan and mask the joining surfaces before painting. I use multitude different masking mediums.  Pieces of stripped wire  insulation, heat shrink tubing (for round items), masking tape, and lastly liquid masking medium.  Evne with bare plastic I often still use CA glue or 5-minute epoxy (because I like using those over solvent cements for styrene).  Planning ahead, parts prep, masking, and choosing from multitude of adhesives is what makes for a good modeler (if I might say so myself).

[NOBLNG]

These are all of the “plastic melting” glues that I have. I use the Tamiya Quick Setting stuff now almost exclusively unless a non-solvent glue is required. They all work well in my experience, except the Plastruct. I bought it last week because the shop owner had it on sale so I figured why not? I glued some .156” half round styrene to some rectangle to make a muffler. When dry, I used a pin to dimple the end so I could drill a hole and it split apart.😡 Oh, and the plastic nozzle on the testors always plugs up.🤨

Edited May 6, 2021 by NOBLNG