Homeroasters - Home Roasting Coffee Community » BUILDING A ROASTER » Drum Roasters
Who is here? 1 guest(s)
Page 3 of 3: 123
 Print Thread
Cyclops - my 1kg drum build
pjvdl
Top  #61 Print Post
Posted on 04/09/2022 7:25 PM
Hi all. I have been happily roasting since my last post; getting used to how the drum roaster performs. In general, I've been very happy with its performance. It will happily roast 1kg batches.

I am having a bit of an issue with the drum bearings though. I have a 12mm drum shaft and an using FL001 (flange) pillow bearings, which do the job, but I am using standard temperature bearings, which do not cope with the heat.

I am struggling to find anything suitable for higher temperatures. The best I can find is something like https://www.bocabearings.com/products/skfl001-12mm-21409, which is rated to 160C. The internal roasting chamber is getting to around 350C and the drum is getting to around 250C, so although the bearings are mounted externally, I'm still concerned 160C is not high enough.

Can anyone suggest a supplier of high temp pillow flange bearings for a 12mm shaft who would ship to Austraila?
-- Paul

ECM Rocket espresso
Eureka Mignon grinder
500g BBQ rotisserie roaster
1kg drum roaster
 
UmMerkur
Top  #62 Print Post
Posted on 04/11/2022 2:01 PM

Quote

pjvdl wrote:

Hi all. I have been happily roasting since my last post; getting used to how the drum roaster performs. In general, I've been very happy with its performance. It will happily roast 1kg batches.

I am having a bit of an issue with the drum bearings though. I have a 12mm drum shaft and an using FL001 (flange) pillow bearings, which do the job, but I am using standard temperature bearings, which do not cope with the heat.

I am struggling to find anything suitable for higher temperatures. The best I can find is something like https://www.bocabearings.com/products/skfl001-12mm-21409, which is rated to 160C. The internal roasting chamber is getting to around 350C and the drum is getting to around 250C, so although the bearings are mounted externally, I'm still concerned 160C is not high enough.

Can anyone suggest a supplier of high temp pillow flange bearings for a 12mm shaft who would ship to Austraila?


I had the same struggle of finding a high-temp flange mounted bearing, so I decided to just mount the bearing on 1" standoffs to keep it away from the heat. If you have the extra length in your shaft you may think about that. I've attached an image of my CAD model, should be able to see what I'm talking about.
I'm a little worried about the door hinge bearings, but those are much lower duty so maybe it will be okay?
UmMerkur attached the following image:
03-07-2022_fullview_resized_1.jpg
Behmor 1600+, Fresh Roast Plus 8, Poppery II; Lelit Bianca V2, Eureka Mignon Specialita', V60, Breville SGP
 
allenb
Top  #63 Print Post
Posted on 04/11/2022 2:29 PM
The most I've heard of anyone doing, and that was due to grease separating and drooling, is go to high temp grease instead of standard. I know of no reason to look for any exotic bearings for high temp especially with the remedies just mentioned (space them away from the front plate a tad).

Paul, what are your bearings doing causing you to replace them?
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
pjvdl
Top  #64 Print Post
Posted on 04/11/2022 10:00 PM

Quote

allenb wrote:

The most I've heard of anyone doing, and that was due to grease separating and drooling, is go to high temp grease instead of standard. I know of no reason to look for any exotic bearings for high temp especially with the remedies just mentioned (space them away from the front plate a tad).

Paul, what are your bearings doing causing you to replace them?


My front bearing completely disintegrated; caused by the bearing covers becoming heat affected and the lubricant (greese) breaking down. To be fair, these were relatively inexpensive bearings, so I think the covers were a cheap plastic.

I was already thinking about separating the bearing from the heat as per UmMerkur's suggestion, so I think I will probably go with a higher quality SS bearing as I listed in my previous and separate it slightly from the drum face. The existing shaft has enough slack that I should be able to get a gap of 5 - 6mm. An air gap even this small should be enough that 160C rating will be sufficient.
-- Paul

ECM Rocket espresso
Eureka Mignon grinder
500g BBQ rotisserie roaster
1kg drum roaster
 
pjvdl
Top  #65 Print Post
Posted on 04/11/2022 10:01 PM

Quote

UmMerkur wrote:

Quote

pjvdl wrote:

Hi all. I have been happily roasting since my last post; getting used to how the drum roaster performs. In general, I've been very happy with its performance. It will happily roast 1kg batches.

I am having a bit of an issue with the drum bearings though. I have a 12mm drum shaft and an using FL001 (flange) pillow bearings, which do the job, but I am using standard temperature bearings, which do not cope with the heat.

I am struggling to find anything suitable for higher temperatures. The best I can find is something like https://www.bocabearings.com/products/skfl001-12mm-21409, which is rated to 160C. The internal roasting chamber is getting to around 350C and the drum is getting to around 250C, so although the bearings are mounted externally, I'm still concerned 160C is not high enough.

Can anyone suggest a supplier of high temp pillow flange bearings for a 12mm shaft who would ship to Austraila?


I had the same struggle of finding a high-temp flange mounted bearing, so I decided to just mount the bearing on 1" standoffs to keep it away from the heat. If you have the extra length in your shaft you may think about that. I've attached an image of my CAD model, should be able to see what I'm talking about.
I'm a little worried about the door hinge bearings, but those are much lower duty so maybe it will be okay?


Thanks for the suggestion regarding the separation. I have been running my roaster for over a year with a similar door hinge setup and I haven't had any issues on that front, so you should be okay with yours. The photo below shows after a year's work (with a replacement main bearing which I had spare).
pjvdl attached the following image:
20220412_123233.jpg
Edited by pjvdl on 04/11/2022 10:07 PM
-- Paul

ECM Rocket espresso
Eureka Mignon grinder
500g BBQ rotisserie roaster
1kg drum roaster
 
renatoa
Top  #66 Print Post
Posted on 04/12/2022 1:15 AM
What about using a custom made "bong", as those used by Pavoni users, to insulate the group from the boiler... ThumbsUp
 
pjvdl
Top  #67 Print Post
Posted on 04/16/2022 6:31 AM

Quote

renatoa wrote:

What about using a custom made "bong", as those used by Pavoni users, to insulate the group from the boiler... ThumbsUp


Was thinking about this as well. Thinking a simple silicone barrier, insulating the bearings from the heat of the chamber.
-- Paul

ECM Rocket espresso
Eureka Mignon grinder
500g BBQ rotisserie roaster
1kg drum roaster
 
Page 3 of 3: 123
Jump to Forum: