Quest M3 Drum Diameter?

#1: Post by **TomC** » July 3rd, 2012, 1:28 pm

I am kicking around the idea of insulating my drum on my Quest and wasn't exactly sure of the diameter of the drum. I was hoping someone here might know, so I can save the time of pulling the drum myself, just to put it back together before anything arrives. I'm guestimating it's somewhere near 15"?

Thanks

July 3rd, 2012, 1:56 pm

Curiosity got the best of me

Only took 6 minutes.

Drum diameter = 4.44 inches

High school math = 13.94 " or 355mm

My drum thickness happens to be a paltry 1.90mm

#3: Post by **tekomino** » July 3rd, 2012, 2:06 pm

Tom,

What exactly are you trying to accomplish by drum insulation? I see absolutely no need to insulate the drum on Quest since its roasting perfectly. Actually I would not change anything on roaster itself since that would change its roasting dynamics from design specs and roaster as it is works just fine...

In another words, if you are unhappy with your roasts, its you not roaster.

July 3rd, 2012, 2:13 pm

I know.

Insulation can be removed.

I'd like to see if I can maintain a higher ET with slightly less power. Also, I want to learn how to end my roasts from 1C onward, with as little fan as possible. Not that these two phenomena are related, but I'll have fun playing around with it.

#5: Post by **another_jim** » July 3rd, 2012, 9:19 pm

Don't insulate the drum itself, you would keep out the heat, and probably damage the roaster. You can wrap bonded insulation on the outside like I did, between the case and the grill. This will get you slightly more efficiency, i.e. the same bean profile at lower ETs or higher charges. There is not much to it at 100 to 175 gram loads, but it does make roasts at higher loads noticeably faster. Not sure if it is worth the aesthetic ding.

#6: Post by **dustin360** » July 4th, 2012, 2:21 am

Ive tried wrapping towels around the outside of the shell as well as placing them below the drum. This didnt seem to speed things along, but It did make it harder to slow down the roast as first crack set in. So for me it made the roaster harder to control.

#7: Post by **Arpi** » July 4th, 2012, 7:24 am

Insulating the "case" (most outer shell) helps to shorten the profiles during the winter (cold room temperatures). Otherwise the beans could get burnt defects when using too high drum temperature to achieve short profiles. It acts as a temperature barrier and helps when there is a large gradient of temperature. For example, it would help when roasting in a garage in the winter.

Cheers

July 4th, 2012, 6:02 pm

Right after I pulled the drum yesterday, I altered course. I ended up painting the the outside of the drum with a high temp (1000°) flat black paint.

It's already gone thru a "burn off" it took only about 10 minutes till there was no more odor. I carefully masked off the internals of the drum before painting it. I haven't done a test roast yet, but likely will tomorrow.

I realized if I wrapped the drum itself in insulation, it would take forever to let the heat in, then once it was in, it would take forever to get it out.

#9: Post by **another_jim** » July 4th, 2012, 7:06 pm

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.

#10: Post by **tekomino** » July 4th, 2012, 7:11 pm

It could have been worse. He could have bought heat gun