Dear Forum,
Does anyone know of a glue that is truly sandable? I was thinking of trying mixing microballons with titebond, and thinning it a little.
Thanks!
Mike

Duco. Still available after all these years.
Ambroid . . . . if you can find it.
If you use a lot of microbaloons, like mostly microbaloons, epoxy will sand readily.

I think the real question is being, "Do you know of a glue" softer than the adjacent materals? As you mentioned, finding a glue is the easy part. Sanding off the excesss is the hard part.


Wm.

I use Ambroid or Titebond 1 as these will readily sand. The real secret it to not leave a lot of the excess glue on the wood surface when you build. Wipe off the excess immediately and let the glue dry so it doesn't ball up when sanding. I use 180 and then 320 grit when sanding these glue lines.

Soft landings,

Joe

Most or all of the PVA (Poly Vinyl Acetate) white and aliphatic resin yellow wood working glues are somewhat rubbery when you try to sand them. Hence they resist being cut down and the wood around them takes the brunt of the abrasion.

As mentioned keeping the glue lines thin and wiping away the excess (as opposed to smearing it around) helps a lot. And once down to the sanding a proper block to support the paper and using fresh sandpaper that cuts rather than plows helps a huge amount as well. With a fresh sheet you can use light force and guide the block more effectively so you concentrate the cutting on the glue line. Then blend the wood to suit.

CA glues are notoriously harder than balsa but they are at least not rubbery. But fresh sandpaper and a block for support is still mandatory.

In both cases only the final smoothing sanding should be done with folded over "loose" sandpaper.

Sigment, Ambroid and Duco are all nitrocellulose plastic dissolved in solvent style glues. These have the advantage that the resulting plastic sands very easily. Very much like balsa in fact. For use on structures where there will be a lot of exposed glue lines that will need sanding I still prefer to pull out this style of glue.

Ambroid and Elmer's Carpenter glue work well for me. The Carpenters glue seems different than the other "white" glues....

Carpenter's glue is not white glue, it is Alphatic glue. Like Titebond.

I use all the types of glues. It takes a while to learn when to use what. Like most here have said cleaning up the glued joint is the best way to keep your model smooth and finished with little sanding. Buy a pack of bamboo skewers at the 99cent store. Then sand the ends to a few different shapes so you can clean up the joints.....sharp flat, sharp point, dull point, angled, etc. The dull point will leave a fillet in corners. The angled will reach into hard to access joint and wipe it clean. After you lift the structure from the plan/wax paper you may have some cleaning up to do with a sharp razor but the glue that's left is so thin you can see through it. You can also use the bamboo to apply glue carefully. A stick with a short .031" music wire glued into the end makes a great way to apply CA carefully. Put a puddle of CA on an old jar lid and pick some up. Bend the wire into a V shape so you can pick up more. My favorite glue is Tite Bond. Use Duco if you want to unglue something in the future with acetone. This is good for stabs until your model is trimmed.

Thanks everyone! Great advise. Model builders possess a great deal of knowledge, and love to share it with others!

Testers still makes a glue similar to Ambroid's and Duco. I've found Duco in my local Hardware store.

Add west system 407 to any epoxy it sand very well.
Also mix light weight Spackle and water based poly, 407 works with this too.

PVA (wood glue) and epoxy via thinning (denatured alcohol) and/or microbaloons. All easily sanded.