Glue
- Thread starter Muskieman
- Start date
Selector
Well-Known Member
Hello. I would not personally place the two materials, ground foam and its gluing medium, directly onto plywood. I would at least try to seal the plywood with some latex paint first, partly to render its surface more of an earth colour, and partly to help the plywood to keep its shape and dimensions with changes of humidity, which your glue in the quantities needed to do a good job of fixing the ground foam will induce...possibly.
Although plywood is much more stable, generally, than linear milled lumber, it can still move around enough to make a kink or two in your tracks and/or roadbed.
Be that as it may, you can initially spray an area with your glue mixture (I'll get to that presently), sprinkly the foam in at least two colours and textures if possible, and then add an overspray for insurance. You can spray or dribble with a vessel that allows you to dribble the mixture if your spray displaces too much of your nicely laid foam.
If you want a cheap and effective mixture, buy yellow carpenter's glue or the white glue equivalent, and mix it in a ratio of about 5-7/1 with water. Add two drops of liquid dish detergent to help the glue to overcome natural surface tension on both your ballast, if you do that, and the ground foam. Mix it all well, and then apply as suits your abilities, spray bottle or a dribble topped bottle (some wood glues come in a bottle with a nipple that you must twist to open the aperture...this is ideal, but you'll have to decant much of the glue volume first).
For quantities, you don't need everything awash, but you do need it well wetted so that it dries well fixed in place.
Does that make sense?
Although plywood is much more stable, generally, than linear milled lumber, it can still move around enough to make a kink or two in your tracks and/or roadbed.
Be that as it may, you can initially spray an area with your glue mixture (I'll get to that presently), sprinkly the foam in at least two colours and textures if possible, and then add an overspray for insurance. You can spray or dribble with a vessel that allows you to dribble the mixture if your spray displaces too much of your nicely laid foam.
If you want a cheap and effective mixture, buy yellow carpenter's glue or the white glue equivalent, and mix it in a ratio of about 5-7/1 with water. Add two drops of liquid dish detergent to help the glue to overcome natural surface tension on both your ballast, if you do that, and the ground foam. Mix it all well, and then apply as suits your abilities, spray bottle or a dribble topped bottle (some wood glues come in a bottle with a nipple that you must twist to open the aperture...this is ideal, but you'll have to decant much of the glue volume first).
For quantities, you don't need everything awash, but you do need it well wetted so that it dries well fixed in place.
Does that make sense?
I do it slightly differently. First, Crandell is right about sealing the plywood with an earth color primer. It both seals the wood and makes it so less than 100% coverage of ground foam still looks OK. I spread the ground foam right after I paint the plywood so you get some adhesion from the drying paint. Once the paint is dry, use a spray of 50/50 water an 70% isopropyl alcohol. This breaks the surface tension of the material and helps to get it good and wet. Next, apply the glue as Crandell suggested, either with a dropper or spray bottle, depending in the area you need to cover. Then, LEAVE IT ALONE. It may seem like it will never dry and can take up to three days depending on the temperature and humidity but it will dry and you have a bulletproof layer of ground foam.
