There are the following points to judge the quality of wood glue
Test glue amount
Take the same weight of glue, compare the size of the actual glued area, and calculate the amount of glue applied per unit area. A good splicing glue can paint more splicing area. If the price of glue differs by 10%, the amount of glue applied per unit of gluing area will differ by 10-40%, which is what we often say “expensive to buy, equivalent to use”.
Detect glue solid content
The effective solid content of water-based wood glue is determined by the amount of polymer. Bad merchants will reduce costs and increase the solid content by using a large amount of fillers, falsely claiming that the higher the solid content, the better the quality of the glue. The solid content of the glue is pseudo-solid content, so it does not mean that the higher the solid content, the better the glue.
Test glue water resistance and weather resistance
The denser the wood, in the season when the humidity changes greatly in the morning and evening, the board spliced with glue must withstand blisters or boiling, and then bake the test. Otherwise, the splicing surface is easy to crack, and the loss is serious, which is a waste of factory costs. The high molecular polymer used in a good glue has excellent water resistance and baking resistance. The price of the required raw materials must be higher than that of the non-water-resistant and baking-resistant polymers. The synthesis process is also complicated and the processing cost is high. Water resistance and weather resistance can be evaluated according to Japanese JAS standard, European EN204/205D4 standard and cold and heat cycle test.
Test glue solvent resistance
After the assembled board is sprayed with paint, there may be uneven joints or tooth joints, which is because the glue is not resistant to solvents and is swollen. The spliced board can be soaked in Tianna water (banana water) to see if it is swollen to test the solvent resistance of the glue. Low-end wood glue has poor solution resistance.
Look at the environmental protection indicators of glue
The raw materials used in good wood glue are high-value, environmentally friendly, and safe for glue workers and consumers. In particular, the preservatives and plasticizers used are environmentally friendly. Mainly see what valuable environmental protection signs the glue has
I also wrote about how to choose a good wood glue before, and I will add a few more today.
