Rob,
The Harbor Freight unit is "concentric" in the sense that the
heat is provide from all around the roller assembly. It is not
concentric with either roller. There are two heaters mounted on
opposite sides of the rollers, and an aluminum structure that is
manufactured to fit around the rollers. The aluminum structure is
actually two pieces that are separated to form the slots for the
paper path.
The BOM for this unit is mostly irrelevant. By the time the mod
is done, not much of the original circuitry or wiring remains. The
temperature control thermoswitch is removed,and replaced by the
temperature controller I referenced yesterday, the thermal switch
that controls the ready light is removed because it operates at a
temperature that is irrelevant. What remains is the small circuit
board that holds the ready LED and the power indicator LED, and
the ON/OFF switch. This board has two rectifiers, two resistors
and two LEDs. The motor remains, the heaters remain and the
thermal fuse remains.
There are some photos of the interior of the laminator here:
https://www.flickr.com/photos/15304611@N03/sets/72157635447779272/
This mod is one that adds a dimmer in series with the motor, so
most of the pics have to do with modifying and mounting the
dimmer, but there a few that show the motor, the heater and the
circuit board. The heater control thermoswitch is on the underside
of the heater assembly, and not in view in these pics.
Really? This grabs my attention.
What make and model?
Can you take a picture and share?
Is there an online parts list we can eyeball that shows how concentric heaters are mounted?
On 12/31/2016 11:53 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote:
But, but the heaters are concentric with the rollers (or at least they are in my laminator) so
stopped/forward/reverse should make no difference.
Dave