Start by performing regular cleaning, maintenance and lubrication on the unit. This is vitally important to the longevity of the glue pot. Since each manufacturer of edgebanders has a different recommended procedure for this, refer to your machine manual for specific information on safety and cleaning procedures.
After you have reviewed your machine manual, you will typically see that the following steps should be followed in properly adjusting your glue pot.
After cleaning and inspecting the glue pot, adjust the strike plate or shoe.
There needs to be a 4/1000” or 0.1 mm gap between the shoe and the roller. This prevents the panel material from riding against the roller causing chipping of the panel and premature failure of the roller.
Check the amount of float or deflection on the entire glue pot as the panel is fed through the machine and rides against the strike plate or shoe.
When properly adjusted, the glue pot should deflect or float 1 mm. It takes a trained eye to visually check this movement. This best means of checking or measuring this would be to utilize a dial indicator mounted on a magnetic base referenced off the side of the glue pot.
Clear acetate is loaded onto the machine similar to standard coiled edgebanding.
The acetate (Figure 3) is helpful to check the glue film thickness on the panel because it is transparent and does not have a primer on the backside. This enables you to easily pull the tape off when examining the glue line on the panel.
Set the proper film thickness by adjusting the opening of the gates. Remember if you have a two-gate system (Figure 4) be very careful about opening the return gate first. Otherwise hot melt will spill out and you will quickly have a major cleaning job. The proper film coverage is based upon your desired results and should be such that there are no open voids on the core surface (Figure 3).
The return gate (Figure 5) on a gravity style glue pot should always be opened first and closed last in order to prevent the glue from spilling.Open the return gate far enough to allow for proper set-up of the application gate. Now open the application gate (Figure 5), which is used to meter the correct film thickness. After the proper film thickness is set, the final position of the return gate should be adjusted. Push the return gate handle closed until it is 1/16” further open than the application gate.
If you happen to notice that the glue coverage is not consistent from the top of the panel to the bottom, consider the following:
- Check the panel edge squareness from the panel saw (Figure 6).
- Verify that there are no obstructions in the glue pot or on the gate (burnt glue).
- If you are sizing the panels on the edgebander, verify that the tooling is set correctly. The same would be true for panel edges, which are prepared only on a sliding table saw or panel saw.
If the problem still persists, adjust the glue pot perpendicularity. When testing be sure that you are using a MDF panel that is thicker than 1” or 25.4 mm that will better illustrate the problem.
Remember, unless the glue pot is adjusted correctly, the edgebanded panels will not be acceptable. It is through these steps that will assist you in improving your machine performance, product quality and most importantly reduce machine downtime.
Checklist to maximize your glue pot
- Lubricate glue pot daily
- Clean glue pot regularly
- Perform standard maintenance
- Adjust strike plate gap
- Check deflection
- Adjust glue film thickness
- Check glue film coverage
Want to learn more?
Stiles Education offers edgebander maintenance courses for both Brandt and Homag machines. For in-depth information on glue pot rebuilding, troubleshooting and preventative maintenance, sign up today.