I am a modeler from years ago and just now starting again. I remember a weld glue called Micro Weld. It came in a small square bottle with its own brush. It was great. The glue did not dry up while you were applying it to both halves of a fuselage. After applying the Micro Weld, you would put the two halves together and squeeze for a tight fit. You could actually see the plastic ooze from the seams. Sand, rescribe the panel lines as necessary. Very little filler would be needed. I have searched high and low for it with no success. All the hobby shops say they do remember it, but it is no longer available. I have tried Tenax 7, but the stuff dries up even before I get a chance to dip my brush in the bottle for more. I’ve read that IPS Weld-On #3 is good. Can anyone provide any advice on a good weld glue?
Hey Doug, welcome back! Tenax 7 is wonderful stuff if used correctly and is probably the best out there for melting seams. I use it for all my styrene gluing needs. The trick is to work quickly because, as you stated, it does evaporate quickly. Just keep applying it to the seam and squeeze. You can also use “Tamiya Thin Cement” with the green lid, which is slightly less etheral in my experience. I just don’t feel its quite as “hot”, so to speak, as Tenax in fusing plastic, but does still do the job. I have actually filled an old Tamiya Thin Cement bottle with Tenax since I like Tamiya’s included applicator better than theTenax one. This is my normal method of application which works well for me. Good Luck.
I’ve got and used the Testors Pink Label, Tamiya Extra Thin, Tenax 7, and Weld On 3, plus the Testors Red Label liquid cement and the clear parts cement and a variety of cyano. I’ve only been back into the hobby for about 18 months at this point, but I’ve used all of these at some point and screwed something up with each at least once, so I have at least some slight experience.
In terms of heat it’s: Pink Label…Tamiya Extra…Tenax 7…Weld On 3. Pink Label is only useful for sticking on small parts or temporary joins where you want to be able to pull it apart without much damage. Tamiya Extra Thin and Tenax gets by far the most use… I tend to save the Tenax for main joints like wing roots and fuselage halves, and the Tamiya for most everything else. I don’t see a LOT of difference between Tamiya and Tenax, but the latter is definitely a bit hotter. You’ll get a more noticable plastic ‘bloom’ from a good weld. The Weld On 3 is really hot, and I use it when there is a lot of resistance to the parts staying staying in place or a lot of weight. You’ve got to be really careful with it, though… it’s great so far on Trumpeter plastic, but I did some damage to a seam with it on a Hasegawa 109. Some plastics it just eats to a goo in no time flat.
Now, the only of these that dries slow enough to be useful in the way you want to use it (coat, then join) is the pink label. The others evaporate too fast. But keep in mind that’s how they’re designed. You hold the parts together (or clamp, or temp join with tape, or whatever) loosely and apply the solvent to the seam, then immediately force them together and get your plastic bloom. Tamiya, Tenax, and Weld On don’t even need a loose gap; capilary action will work even if you’re holding the parts tight together. For long seams you can’t even really do them all at once, like a fuselage join. You need to hit an inch or so of the seam with the solvent, hold it together to get the weld, then move on to the next inch. Anything else and the solvent will just soften the plastic for 10 seconds and then harden right back up before you can get them set against each other.
If you want to put a glue on parts apart then work them together you’ll need either tube glue or cyano. I used to use medium gel on most everything till I finally took the forums advice and used the solvents, mainly due to the irritation of dealing with the dispenser. No mater how well you take care of your various plastic tips for CR, you’re going to clog fairly soon. Of course you must have it for PE or other non-plastic things, but I’ve moved to the solvents for everything esle.
Being in contention for the cheapest guy since Jack Benny, I have taken to using MEK for all my general styrene cementing. You can get a quart of the stuff at the home improvement stores for the price of a few bottles of branded cements. It flows well from a brush or ruling pen, beads the styrene like Tenax and has provided joints as strong as any of the hobby cements I have used.
