Liquid Cement

Tenax should almost immediately (within a few seconds) start to melt/soften the styrene. Are you sure it's styrene you're attempting to cement and not ABS?

It all depends on the application.

The "thin" liquid cements work best when the parts to be joined are held together and the cement is flowed into the join. They are ideal for long, uninterrupted runs like fuselage seams - hold the parts together and touch the tip of the brush to the seam. Capillary action will draw the cement into the seam and you're done.

They do not work quite as well if you apply the cement to the parts separately, as much of the cement will evaporate before you can bring the pieces together (and before it has time to "melt" the plastic sufficiently for the parts to join securely).

PS: Try the Tamiya "Extra Thin" liquid cement, it's magic

Phil_H wrote:

They do not work quite as well if you apply the cement to the parts separately, as much of the cement will evaporate before you can bring the pieces together (and before it has time to "melt" the plastic sufficiently for the parts to join securely).

Ditto to that.  I used to use the testor liquid cement as well and half of the contact edge would already be 80% dry by the time I picked up the other piece to join them together.

The real trick with using liquid cement successfully is to "unlearn" the techniques we have learned over time while using tube cements (which I am sure almost everyone here started out using).

The "standard" technique when using tube cement is to apply cement to a part and then put it in place. This does not always work with liquid cements.

When using liquid cements, this process is reversed - the parts are put into their final position and then the cement is applied. This also means that you need to study your assembly instructions carefully and dry-fit your parts before appying cement (and this is not a bad thing ). When the parts are in place, touch the tip of the brush to the join and the cement goes exactly where it's needed - no mess, no blobs and very little to clean up,

However, there is a significant downside to using "thin" liquid cement. Due to the very low surface tension of "thin"  liquid cements, they have a tendency to follow seams, panel lines, ridges etc by capillary action (and, if you're unlucky or just plain sloppy, between your fingers and the parts you're trying to glue), so be wary, because a little goes a long way. For this reason, it's not great for applications where there is a lot of fine detail or in assemblies where there are moving parts in close proximity.

I would suggest also picking up a bottle of "thicker" liquid cement with a needle-tip applicator for those jobs where "thin" liquid cement just won't do. eg. Revell Contacta, or similar ( my personal favourite is Faller "Expert", though I am not at all sure of its availability these days - the one I have dates back to the late 80's and is still going strong.)  

Personally, I wouldn't go back to tube cement unless there was absolutely no other alternative available. Though I am just getting back into model building after a break of about 12 years, the last time I used tube cement would have been in the early 80's.

Once you get the hang of using liquid cements, you won't need (or want) to use anything else.  

As said above, the thin stuff evaporates really quickly. You can apply a bit to the part, hold it in place, then flow some more glue into the join.

I personally recommend the Tamiya liquid cements. They work really nicely, no matter how you apply them.

Rather than use th eoversized and clunky brush that comes with these, try to find an old drafting set like this

. The pens are great for this and the compass is very useful for measuring things as well as drawing a circle. (This one's on Ebay right now under "technical pen")