another_jim wrote:If you melt the heaters, don't say you weren't warned; if you spend 2 hours warming up your drum, don't say you weren't warned. What on earth gave you the idea of putting insulation between the beans and the heatsource? It makes about as much sense as insulating the space between your fireplace and the living room.

Wow, nice way to get thrown under the bus and then mocked for something I didn't even do.

Prior to me reading your old 35 page thread from when you first got your Quest, I hadn't even seen or read what you did to modify yours. I just remember you writing that you "insulated the drum". I honestly didn't give it much thought until I had the roaster apart for the first time today.

But like I said earlier, when I finally took mine apart and had it in hand, it donned on me that putting any insulation directly on the drum wouldn't work, for the reasons I already mentioned. If I consider insulating the outer shell, I'll make certain not to mention it here.

Don't take it too hard Tom, we are just having little fun on your account Its not malicious.

I know we all tinker and try things and sometimes they result in something good and sometimes they are disaster. PM me if you need any help with Quest and I'll share everything I know.

Yeah I'll be sure to do that.

When I dug thru McMaster/Carr, I was looking for a high temp safe material to wrap around the drum that was black to absorb more heat faster, and would increase the density of the drum. They don't have anything other than carbon fiber, and it has no adhesive properties. When that was a bust, I realized it would be just as effective to paint the outside of the drum a matte black.

Today I was able to run a roast at a lower MET (450-470) yet still having a wonderfully fast ROR on my BT, like I wanted, without using maxed fan or amp settings.

Ah, now I get it. This is an insulating paint that increases the heat transport and lowers the R-value of the drum.

TomC wrote:Today I was able to run a roast at a lower MET (450-470) yet still having a wonderfully fast ROR on my BT, like I wanted, without using maxed fan or amp settings.

Not to rain on your parade, but what you are experiencing is indicative of alteration of roaster dynamics.

Keeping a lower MET is not analogous to better system performance. Air temp and flow rate govern the rate convection flow to the beans. By modifying your drum in the described fashion, you are biasing your roaster for conduction heat flow. This will impede your ability to utilize convection at certain key stages of the roast (entry to 1c, finish).

The Quest is a very well designed roaster that people do not need to outsmart. Thermodynamic balance is not something easily achieved. I hate be cliche but, "if ain't broke, don't fix it".

Hehe, weren't you just encouraging someone else off the fairway in another thread? Maybe if he used a heatgun in the trier now to balance it all out ...

Hey tom, will you post a screen shot of your improved heat transfer? Id love to see how much different it is, now that the outside of the drum isnt reflective.

jammin wrote:Not to rain on your parade, but what you are experiencing is indicative of alteration of roaster dynamics.

Keeping a lower MET is not analogous to better system performance. Air temp and flow rate govern the rate convection flow to the beans. By modifying your drum in the described fashion, you are biasing your roaster for conduction heat flow. This will impede your ability to utilize convection at certain key stages of the roast (entry to 1c, finish).

The Quest is a very well designed roaster that people do not need to outsmart. Thermodynamic balance is not something easily achieved. I hate be cliche but, "if ain't broke, don't fix it".

I never considered it broke, or improperly designed. I agree with all the things you wrote and I understand them all. I wanted the roaster to function better as a conductive roaster than it did before I painted it. All in all, I don't expect my changes to the drum to greatly differ from anyone else's well used drum that will likely eventually get darker anyway.

Here's a screen shot of the faster ROR with a lower MET. This was my first roast with it since I painted it, and will definitely charge with a lower BT/MET on the next batch.

I started this roast with a BT close to 370. I roasted 120g of beans.

haha, awesome. I love the title of that roast. And It looks shockingly faster than i would of thought. Looks like painting the drum black has made a huge difference its ability to absorb heat from the elements.


*also it was really good idea not to use the don p as a test roast after the painting.