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The latest Quests have neither intake hole nor tubes. Instead, there are two slits of about 3 mm width,
one on each side, low down on the roaster. These slits run the entire length of the outer case. At least
some of the roasters with a lower chaff drawer have this feature, the slits being on either side of the
drawer assembly. To convert older Quests to something similar, block the air intake hole, cut narrow
slits in the lower case and open the slits to about 3 mm by bending. Make adjustments by changing the
bend.
Air Exhaust:
The air from the blower exits the roaster at the back via slots in the case. The aperture
size provided by these slots is significantly larger than the aperture of the air entrance hole, the tubes or
the slits. Nevertheless, some owners cut away the metal between the slots to increase airflow. This
modification also makes it easier to clean the blower fan. Note that there are two sets of slots, side by
side. The outboard set serves the blower, while the inboard set ventilates the electrical cabinet. The
latest Quests have the metal between the slots opposite the blower exhaust twisted to direct the exhaust
somewhat upward.
Increasing Capacity
Painting the drum
Some Quest owners–to increase the maximum batch capacity or alter the roast environment’s thermal
dynamics–paint the roasting drum’s exterior with high-heat matte black spray paint. Doing so causes
the drum to efficiently absorb and conduct more infrared heat to the roast chamber independent of
airflow speed (convection). Increasing the drum’s ability to absorb infrared heat increases the batch
capacity, and heat changes are faster, even for large batch sizes (EG. <10 minutes, 300g roasts on an
M3).
This modification is a bit difficult to reverse. Also, it may become challenging to roast small batch
sizes (EG. <150g) without introducing tipping or scorching. This modification may make flavour
profiling more difficult because the roaster will operate slightly more conductively and less
convectively.
Making this modification is relatively easy. First, remove the drum and prepare the exterior surface by
scuffing it with 120-grit sandpaper. Wipe off any grit and debris. Then, mask it so that spray paint
cannot coat the drum shaft or the drum’s interior. Next, spray high-heat (600 C / 1200 F) matte black
paint in several light coats according to the container’s instructions. You can use BBQ grill paint for
this. Run the roaster for a prolonged period (EG. 30-45 min) at about 200º C to burn off any volatile
components before roasting coffee.
Insulating the Roasting Chamber
Some owners add a layer of heat-proof insulation around the exterior of the roasting chamber. This
insulation allows the Quest to retain more heat, increasing capacity and the speed of heating. However,
the downside is that if the user wishes to dump heat when a roast is getting too hot, it will be slower.
