Troubleshooting an Edgebander Pre-Heat Fence

The pre-heating fence on an edgebander is a seldom-used accessory. It may be repairable with off-the-shelf components. January 2, 2012

Just picked up a 2001 Bi-matic Silence Plus edgebander and am in the process of setting it up. The only tool now that isn't working is the pre-heat fence. I have tested that power is running through the thermostat correctly to the point it runs directly to two resistive strips attached to the back of the infeed fence. Unfortunately I don't know how to test these strips. Is this component something that breaks with time?

Forum Responses
(Cabinetmaking Forum)
From contributor D:
Check them with an ohm meter. There should be resistance. If not, they're toast.

From the original questioner:
Thanks. I'll check it out. Are they hooked up in sequence (if one dies it'll break the circuit and they will both quit)?

P.S. I've checked online and there seems to be very little info on Bi-matic (sold by Akhurst). Wonder how many people own their banders? They weren't at AWFS this year. Smaller company?

From contributor M:
As said there should be resistance and not too much. I do not know how many watts the heater is but the formula for finding resistance is I=V/R. Most higher power heating elements are around 20 ohms. If you see a lot more, like in the hundreds of ohms, it is shot. Often these types of heating strips are off the shelf components. Call a supplier of heating elements. Or don't worry about it - unless you are in a frozen place, the heater doesn't do anything.

From the original questioner:
Thanks. I don't know what use I would have for a preheat fence anyway. Most of the machines I was looking at before I bought this didn't have that feature. Is it an alternative to increasing glue pot temperature? Is poor adhesion the symptom that would warrant the preheat?

From contributor M:
As I understand, it is supposed to help when it is really cold. My shop in Texas never needed that, and my shop now really doesn't need it. But it is definitely not meant to supplement the gluepot/roller temp.

From contributor L:
I don't think they are of much use. Our bander feeds at about 1'/second. How much can it heat the edge in that time?

From contributor H:
I had a bimatic in Canada and it had a preheated fence. Never used the feature, but it was a great machine for the money. Bought it from Akhurst in Montreal. Never seen one here in the US. The Cehisa is very similar. Small footprint with great features. Way better than the HolzHer1403 I owned before it.

From contributor U:
No, it isn't an alternative to increasing glue pot temperature. Increasing the glue (pot) temp is only marginally, if at all, effective when it's cold and the PVC doesn't stick. The idea of the fence heater is to warm the board so it won't cause the glue to cure before the PVC is applied.

From the original questioner:
Thanks for the tips. I am in eastern Canada where it can get cold in the shop. I'll know to use the pre-heat if the banding isn't sticking well on those cold days.

So I checked the resistance and am not getting anything back on the meter, even on continuity. Could this be a broken wire, or does it sound like a dead resistive strip (they are both giving same reading)?