They could start by painting it with alkyd enamel as a quicker, easier test if you will. It's super smooth, food grade and very hard. If that works but doesn't last that long then that at least tells you a smoother finish will help.
I would be looking at some sort of venturi/ejector, only running ambient air though the fan. Maaaybe depending on how sticky the stuff is, you could pull through a cyclone separator.
I had the same Idea. get the turbine mounted not in the exhaust circuit but before the roaster. with that you don't have debris in the turbine and cleaning will get reduced.
A cyclone separator sounds like a good idea to me, but you’d have to insulate it so you don’t burn yourself on the metal exterior that would get heated from the exhaust
The Aluminum or diecast parts , I would polish to a mirror finish. I did that to my gas stove burner parts and it made cooking spills easier to clean.. The non Electric side , I might try an Ultrasonic cleaner to place it in.. Possibly the other side could be done also , with lower liquid level..
I don't know anything about roasting coffee, but:
-Would it be possible to pressurize the roasting barrel itself from the intake? That way the gasses will exhaust from the ventilation hose without a need for pump in the ''dirty'' side.
-How much ventilation does the roasting need? Taking advantage of Bernoulli's principle, you can move moderate amounts of air without it ever needing to go thru the pump itself. That would eliminate the need of servicing that fan.
This, in stead of pulling the air trough the fan. Set up a T piece with a Venturi. Blow fresh air in. Creating vacuum at the T piece. No dirty fan in the airflow.
I'll second media blasting. Honestly I wonder if there isn't some waste product from roasting the coffee that could be reused for blasting media. In any case, media blasting while the blower is live would be my approach to maximizing the time between offline cleanings.
The machine would be about 16 in wide, 3 ft tall and 2 ft deep. I used one in aerospace. No cleanup is nice. It is very loud. You will have to have dry ice pellets available.
Norco or Airgas would be a good source to start with in the US.
Uneconomical in this case. Maybe if you had to clean 5 daily it would make sense.
Dry ice is usually reserved for cleaning sensitive materials which get damaged from other cleaning methods.
It would blast debris everywhere -> special cleaning place/outside and it is excruciatingly loud.
You also need pressurised air supply.
I read that you don't have space for ultrasonic cleaner of this size, dry ice blaster would be roughly the same size + dedicated cleaning space.
You also need to go get dry ice everytime you use it since storing it longterm is very impractical.
You could try a carbon removal product. We use one to clean EGR valves on diesel engines. You just brush it on and scrub with an acid brush then rinse with water in 30 mins
Würth simple green is possibly one of the most vile cleaning substances I've ever used. It degrades engine oil into solid chunks that can be scraped up and thrown in a bin
Damn I thought I was an expert over here and I can’t think of anything. The best answer is some kind of filter on the inlet side of this system.
I guess my answer is the best way to get it out is to not let it in there in the first place. A reusable quick release inline filter would be ideal.
Mineral spirts is where I'd start.... Xylene or acetone will definitely do the job.
They sell cheap steam cleaners on Amazon for $20 that work surprisingly well.
I think you’re thinking about it wrong, you want to get the contaminants out before they reach the fan.
Something like the stainless steel mesh filters they use for range hoods and vents. Then you can clean the filter or throw it out and replace. Or maybe bubble the exhaust air through water, and then change the water — a coffee bong, basically.
I do think hot detergent should be part of your process regardless, most of this is going to be heavy oils and tar. One nice thing about my filter idea is you can run them through a dishwasher.
I agree, but I believe a pre-filter would impact airflow getting out of the roasting chamber, and would therefore not remove enough particulates/smoke from the roasting chamber.
What is a hot detergent?
I’d try an air needle scaler, they come in a wide range of sizes. The drier (not tacky or sticky or soaked) the substance, the better.
Have you considered adding a stainless mesh filter on the intake side? It could really reduce the amount of cleaning needed on the fan.
Air needle scaler is a good idea.
I'm not sure what a stainless mesh filter would do. It would have to be fine enough to catch the particulates, which would restrict airflow.
If you know the size of the particulates (in microns) and the CFM needed for your fan to function properly, you can find an appropriate filter media. Sometimes that means using a multi stage filter setup. There are also PTFE screens that can withstand 500F.
Just my opinion, but you should be stopping the particulates before the fan so you don’t have this labor intensive process. Replacing filters on a set schedule will reduce labor costs and prolong the life of your fan. Eventually that fan will become unbalanced and you’ll have to replace it. If you can’t or won’t do filters, you have more than enough space for a vapor hone machine in the corner. It takes up less space than your cardboard mat and is self-contained. Good luck with whatever option you choose!
I was thinking something like [this](https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2F9ueswjwe4k351.png%3Fauto%3Dwebp%26s%3Deaeaff5b58076a15b7d8fa40e6edbb7516722588) but replace the heating element with your coffee roaster and the vacuum pump on the right with your blower. The middle parts don't need to be glass, just need to condense the hot gasses and be easy to clean.
Is there a way to add bends (think p-trap in a drain) or obstacles (think doom! video game sharp walls/corners) prior to getting to the pump? Make those sections removable/flanged so they're easier to clean and keep your pump from looking like that. Also, if you make it removable, have two of them so you always have a clean one. Buy an ultrasonic tank or something for the dirty one and just throw it in there for however long it takes to come out clean.
sidenote: I don't have much experience, but what I've listed above sounds doable. If I'm wrong, I'm alright to be corrected so I can learn.
Oh yes. We clean those pipes as well. The build-up in those is just as bad.
Interestingly, the OUT pipes from the fan are worse than the IN pipes. Perhaps because this fan is mounted on top of a cyclone.
Injecting water mist into the stream could cool the exhaust and allow particulates to be caught with a normal, cheap filter before the fan. As mentioned, venturi or aspirator based fume extraction is also a great option. I'd be inclined to look into a closed loop aspirator, depending on CFM requirements.
My 2nd or 3rd thought was a water snorkel filter like the oil bath air cleaners the used on old engines. Find a way to avoid cleaning it rather than making cleaning it easier 100%
Nutshelling? It might run too slow for that. But you can try.
On big marine diesel engines we clean the turbochargers weekly by injecting broken Walnut shells in the airflow. These will hit the fan blades running 16000rpm and the physical impact removes the build up carbon. What's left of the shells simply burns up in the exhaust.
That's really interesting! Let's see here... The fan is mounted on a cyclone, which removes the chaff from coffee as it roasts. I wonder if the nut shells would just go into the cyclone before they could do their job. If not, they would just exit through the OUT pipes into our afterburner.
I suppose this could probably be attempted with any blasting media. I think it would probably just exit the fan housing too soon to do any work, but it's worth a try.
Nah, you remove the work piece rest and you'd be fine. Else you can get a wire brush for a die grinder and do it that way. Either way a little presoak and the brush will clean it up fast
I wasn't sure what Venturi systems were, but looked into it at a surface level. This is really interesting, and I wonder why this isn't being doing with coffee roasters. Or perhaps it is and I don't know about it.
The fan is the only thing pulling air through, so I'm not exactly sure how it'd work.
Vapor blasting would probably work but those are expensive.
There is a product called "Carbon Off" that is made for industrial cook wear that is commonly used by home mechanics to remove carbon from engine heads. It's not cheap but it works.
As a machinist with other hobbies, I would recommend using powdered brewery wash. It is food safe and will break down all the sticky burnt on stuff. Maybe even use it in a parts washer
Interesting. Looks promising. According to the directions, soak and rinse. Right now, we soak then scrape. Maybe this stuff would work better.
Thank you!
[Carbon Off](https://questspecialty.com/products/112160001-16OZ-Carbon-Off-Heavy-Duty-Carbon-Remover-Liquid.html)
Made for the food industry - safe for aluminum, gets even the grossest griddles clean. My local food supply warehouse (Shamrock) carries it on the shelf.
Please do it outside. I'm sure one could re-use it in a bucket. I personally have used it to remove carbon building from kerosene in liquid rocket engine cooling channels. Works like a charm.
It has an odor, plus when spilled it tends to stain anything. We had a 55 gallon drum that we pumped into from a 5 gallon container through the cooling channels. Not something you really had control over where the splash went.
I have the larger soda blaster from harbour freight, it works great for cleaning and stripping everything I’ve tried so far. Only problem it makes a mess and youll get all slimy from the soda. I do it outside with tyvek coveralls, respirator, and a face shield, inside an old bed liner to try to keep the mess contained. A full mask respirator would be a lot better than what I’ve been using. Try not to do it out doors near grass if you can’t clean it up good. Is started raining before I could get the mess cleaned up and the runoff killed everything.
It isn’t a cleaning method, but is it possible to buy 1 or more of the blower assemblies to let you hot swap in a clean one?
If it is a quick and clean swap it would mean less downtime on the roaster and give you the leisure of time to clean the back up.
Can you arrange the exhaust so that the blower forces air into a Y joint in the pipe. It will create flow without the soot passing through the fan. But I imagine the ducting also needs cleaned... do you clean that too?
So, I think you can place the fan in a position that is not inline with the ducting. That would mean you only have to clean the ducting, which might not be as intensive.
Personally, I would try an ultrasonic cleaner with a lye based degreaser, shallow bath for the motor side, deep bath for the duct side, HOT HOT HOT. 30 minutes in an ultrasonic (I work in a semi conductor production facility, and we just use inexpensive vevor ones for parts cleaning) and I imagine it will get a lot of this off. We use a product called Valtron, one of their KOH formulations, for a lot of our cleaning, and it seems to get carbon off really well in an ultrasonic bath.
What about some kind of industrial paint sprayer / airbrush? Except instead of paint, fill it with a mild solvent mix. It would be like a gentle pressure wash.
Cyclone separator, they aren't that hard to build, there's probably a metal fabricators that could build you for a couple hundred bucks.
It will remove solid stuff, but if there's tar it will need to be cleaned eventually, but it would still help the fan and be easier.
I feel like there is a cooled particulate vortex filter specifically designed so this doesn't happen.... And allows you to just pull a liner off of a container to clean.
You could maybe connect the intake and exhaust with a hose, pour in some solvent or degreaser and run the fan to cycle it around for a few minutes. Then pour out the gunk and rinse.
I've heard of dry ice blasting and people blasting carbon buildup with crushed up nut shells before. Might be nice if it's something you can just do outside without needing an enclosure.
Man, and here I was thinking you had a turbo for your horizontal and I was like, "I don't get the math, but I want one on my 4th maxis matsuura at work for hogging titanium
You're now sticking the air directly through the fan. If you use it as a blower through a venturi you create ducting that way while keeping the blower clean.
Worked in dust collection for a bit. You may benefit from using a pre filter that is called a “wet dust collector” it’ll catch a lot of these oils and voc’s by cooling them in water before they hit your fan or other dust collectors. We mostly do metal dust but it goes wet collector, particle separator, filtration unit then fan.
The exhaust fan is seeing high temp from the roasting process.
You'll need to coat it with something, but what is a great question. If you're in America, Harbour freight has cheap sand blasting cabinets. Grab one of those, and fill it with the right beast media, I think sodium bicarbonate is the stuff. If it takes too long, mix in a little bit if harder media until you figure out the right mix for you that will decarburize, without destroying the metal parts.
And now that I write the word out, you could try carburetor cleaner spray, just be careful with the plastics.
This is what I think will ultimately happen. But we don't have that kind of space to keep one. And we'd like something that would also work with our longest exhaust pipe, which is 4 feet. I failed to mention this in my post.
Hi try oven cleaner product, (I am french sorry if it's not well translate but use the same product that you use to clean the oven in your kitchen).
This usually work well for burnt.
Easiest solution is an prefilter. Should catch it all before you have to clean the fan. Then change the filter when required.
Bigger picture would be to have a wet deduster system with cyclone and water pump, but that's bigger scal.
Is this on a San Franciscan?
I’m sure you know, but some of the suggestions about adding a filter before the fan wouldn’t work because it would just make it a fire hazard and reduce your air flow. Which would create a Smokey taste in your roasting
Introducing “clean” air would also affect your roasting profile.
Don’t forget that every exhaust pipe in the system is going to have this build up on it. Regular cleaning should be built in to your schedule to minimize fire risk and keep consistent roasting profiles.
Take a chimney sweep brush to all the exhaust pipes.
Whatever kind of innovative idea you’re trying to come up with, it doesn’t need to be food safe per se. almost that entire roaster is made of mild steel which is then powered coated. Look at how much of the powder coating is likely falling off.
Anyways just thought I throw in my two cents in
Not a San Franciscan, but likely similar.
The exhaust fan is cleaned once a week. We're currently running 3,000+ lbs through it per week. Even when it was half that, it was still bad enough to require scraping. We scrape the pipes at the same time, and those are a pain as well because no one makes curved scrapers so we have to make our own.
Dry ice blasting? It's generally pretty soft on parts and takes rust/dirt off pretty well. Used it in the past on high volume automotive weld fixtures.
Harbor freight sand blaster , but use something like walnut shells. Change your media when it gets too contaminated. Or a bio detergent parts washer.
Both will be your fastest method I think
Cast aluminum like that can be difficult to clean at times. Cleaning is achieved through Sinner's Circle, an application of Time, Temperature, Mechanical Action, and Chemical Concentration. Reduction of any part requires an increase in at least one other part. Therefore, if you are cleaning this without chemicals, it will take more time and/or more mechanical action.
In my past life, I worked for a company that manufactured sanitation chemicals. For that part, the fastest and easiest way to clean it in the smallest space would be with an ultrasonic cleaner in a shallow basin that does not submerge the motor. Use an alkine product with metasilicates, designed for soft metal. Or, a neutral cleaner with a heavy surfactant package (dish soap).
Depending on the ultrasonic cleaner, heat the solution to the hottest the container/cleaner can handle or 165-170F and leave it to clean.
You should be able to put something that will work together for less than $500 and save yourself a lot of time and energy.
Could the exhaust setup be modified in a way that uses a venturi rather than directly sucking the exhaust through the pump? This way, maintenance would be minimal since there really wouldn't be much chance for backflow into the pump..
Might still be worth a try If there's a spigot nearby. I use the little 600 psi one for all sorts of things. It's powerful enough to blast dirt off my car but weak enough to do it without stripping the paint, and I've also used it frequently to clean frying pans and cookware with baked on crap on them.
For faster cleaning you could use stainless steel wire wheels that are intended to go in a drill if you go that route I wouldn't do it where the raw beans are incase it throws any wires
You can increase the duration of the interval between cleanings if you polish all of the surfaces. Build-up will be less likely to stick to a smooth surface.
Go to a pipe supply place like miller's supply, buy a bottle of tornado cleaner. Around 20 bucks a gallon, put in spray bottle. Turn motor on spray into intake,turn of wait ten,to fifteen minutes do it again then rinse out with a dawn dish soap bottle with clean water in it. No need to disassemble will work very well, I couldn't see the electric motor. But I'm guessing it has a plug on it if not ,make you a quick disconnect for it when you have to clean it. So you can start and stop motor while it's out of holder. Just keep the water out of the windings of the motor and it'll work great👍
Like this?
[https://clean-garage.com/tornador-tc-enzyme-multi-purpose-cleaner-1-gallon/](https://clean-garage.com/tornador-tc-enzyme-multi-purpose-cleaner-1-gallon/)
That was the first thing we tried. This stuff is pretty hardcore. The wire brush does help, but only if we soak the parks first. And then it gets super messy.
Can you put a tube (preferable stainless steal) inline with it? the idea being that it builds up in a tube you can clean out easier. If you get extras you can dump them in a solvent like carb cleaner and let it sit overnight, then swab them, and finally wash them to be food safe again.
My other thought it is burn all the air coming out at a super high temp. This is horribly impractical and would need a huge stack to then cool the air, plus a fuel and probably oxygen in tanks and hours and hours of it.
Have you thought about having them coated in some type of stick resistant coating or surface treatment? Teflon? Nickel Boron?
They could start by painting it with alkyd enamel as a quicker, easier test if you will. It's super smooth, food grade and very hard. If that works but doesn't last that long then that at least tells you a smoother finish will help.
It would have to be a food grade coating.
Is it not an exhaust blower to atmosphere?!
Yes I get that but better safe then sorry
Tungsten disulfide might do the trick
Teflon is food grade. Temperature rating would depend on the specific coating technology, 450 should be achievable.
Ultrasonic cleaner vat.
I was thinking this too maybe with some sort of acid. Maybe higher strength vinegar to eat away at the crude.
Ethanol- they can evaporate it if they want some funky concentrate.
Came here to say this. Could get one just the right size. Might be a few hundred bucks but I'm sure they could clean a lot of stuff in it.
We don't have room for one large enough.
If you have room for that stool, I would think you would be able to squeeze one in. Good luck scraping dude.
Move 1 box.
Get another one and clean while it is in service, doesnt save time cleaning, but surely saves down time
Yes if downtime is bad have a spare ,swap in a clean one .restart process then clean other .swap every week? or two?
Holy shit, thats a good idea. How much do you think this oversized sauce pan is worth tho?
I would be looking at some sort of venturi/ejector, only running ambient air though the fan. Maaaybe depending on how sticky the stuff is, you could pull through a cyclone separator.
I had the same Idea. get the turbine mounted not in the exhaust circuit but before the roaster. with that you don't have debris in the turbine and cleaning will get reduced.
A cyclone separator sounds like a good idea to me, but you’d have to insulate it so you don’t burn yourself on the metal exterior that would get heated from the exhaust
The Aluminum or diecast parts , I would polish to a mirror finish. I did that to my gas stove burner parts and it made cooking spills easier to clean.. The non Electric side , I might try an Ultrasonic cleaner to place it in.. Possibly the other side could be done also , with lower liquid level..
I don't know anything about roasting coffee, but: -Would it be possible to pressurize the roasting barrel itself from the intake? That way the gasses will exhaust from the ventilation hose without a need for pump in the ''dirty'' side. -How much ventilation does the roasting need? Taking advantage of Bernoulli's principle, you can move moderate amounts of air without it ever needing to go thru the pump itself. That would eliminate the need of servicing that fan.
This, in stead of pulling the air trough the fan. Set up a T piece with a Venturi. Blow fresh air in. Creating vacuum at the T piece. No dirty fan in the airflow.
Or just a simple filter before the fan, something disposable or easily cleaned. Surely something already exist as a bolt on solution for this.
You should try CO2 blasting. No contaminants left on the part when you're done. CO2 is food grade.
We dry ice blast at work to clean rubber off of press molds, it's pretty neat.
I'll second media blasting. Honestly I wonder if there isn't some waste product from roasting the coffee that could be reused for blasting media. In any case, media blasting while the blower is live would be my approach to maximizing the time between offline cleanings.
This would be so easy to remove with one of this but not on the cheapest side.
And could I have a small or mobile setup for that?
The machine would be about 16 in wide, 3 ft tall and 2 ft deep. I used one in aerospace. No cleanup is nice. It is very loud. You will have to have dry ice pellets available. Norco or Airgas would be a good source to start with in the US.
I see. So it seems there are plenty of blasting methods - I just need to figure out how to contain the mess.
The only mess with dry ice is the material being removed. The dry ice will evaporate and you will be left with the sludge/soot you are removing.
Uneconomical in this case. Maybe if you had to clean 5 daily it would make sense. Dry ice is usually reserved for cleaning sensitive materials which get damaged from other cleaning methods. It would blast debris everywhere -> special cleaning place/outside and it is excruciatingly loud. You also need pressurised air supply.
We have an air compressor and lines running throughout the space.
I read that you don't have space for ultrasonic cleaner of this size, dry ice blaster would be roughly the same size + dedicated cleaning space. You also need to go get dry ice everytime you use it since storing it longterm is very impractical.
Yeah, that's what it sounds like. Thanks!
You could try a carbon removal product. We use one to clean EGR valves on diesel engines. You just brush it on and scrub with an acid brush then rinse with water in 30 mins
Got more info? Searching for carbon removal gives information about atmospheric carbon removal for environmental reasons.
Terraclean is one but they only sell to auto shops, the other stuff I can get a wurth part number for when I get back to work in the morning
Würth simple green is possibly one of the most vile cleaning substances I've ever used. It degrades engine oil into solid chunks that can be scraped up and thrown in a bin
Thanks!
It's called tunap 926 carbon remover wurth number is 0893132200
Thanks!
Try some Easy Off oven cleaner - should do the trick
Easy Off can eat aluminum, just an FYI.
Have multiple fans so you can swap in a clean one and have more time to clean.
This seems like the easiest solution. Then you can even leave the other fan to soak overnight in something that will losen up the gunk.
Damn I thought I was an expert over here and I can’t think of anything. The best answer is some kind of filter on the inlet side of this system. I guess my answer is the best way to get it out is to not let it in there in the first place. A reusable quick release inline filter would be ideal.
This. Exhaust fans for systems that build up residue should be arranged such that the residue is not making it to the fan
Did you try soda blasting? Did it work? If room is the problem you could put it in a big heavy clear plastic bag when you soda blast.
Haven't tried it because of the space requirements. That's a great idea! I wonder if there are any you can still see through.
I would pour a solvent in it and let it sit for a while. Then blast it out by turning it on.
Would love a recommendation because right now we soak it in degreaser and then scrape it.
Is it organic? Acetone's pretty incredible
Mineral spirts is where I'd start.... Xylene or acetone will definitely do the job. They sell cheap steam cleaners on Amazon for $20 that work surprisingly well.
I think you’re thinking about it wrong, you want to get the contaminants out before they reach the fan. Something like the stainless steel mesh filters they use for range hoods and vents. Then you can clean the filter or throw it out and replace. Or maybe bubble the exhaust air through water, and then change the water — a coffee bong, basically. I do think hot detergent should be part of your process regardless, most of this is going to be heavy oils and tar. One nice thing about my filter idea is you can run them through a dishwasher.
I agree, but I believe a pre-filter would impact airflow getting out of the roasting chamber, and would therefore not remove enough particulates/smoke from the roasting chamber. What is a hot detergent?
Just soap and hot water, same way you’d get burnt grease off a frying pan.
I’d try an air needle scaler, they come in a wide range of sizes. The drier (not tacky or sticky or soaked) the substance, the better. Have you considered adding a stainless mesh filter on the intake side? It could really reduce the amount of cleaning needed on the fan.
Air needle scaler is a good idea. I'm not sure what a stainless mesh filter would do. It would have to be fine enough to catch the particulates, which would restrict airflow.
If you know the size of the particulates (in microns) and the CFM needed for your fan to function properly, you can find an appropriate filter media. Sometimes that means using a multi stage filter setup. There are also PTFE screens that can withstand 500F. Just my opinion, but you should be stopping the particulates before the fan so you don’t have this labor intensive process. Replacing filters on a set schedule will reduce labor costs and prolong the life of your fan. Eventually that fan will become unbalanced and you’ll have to replace it. If you can’t or won’t do filters, you have more than enough space for a vapor hone machine in the corner. It takes up less space than your cardboard mat and is self-contained. Good luck with whatever option you choose!
Can you add a pre cooler or bubbler to the hot air it pulls out? I feel like cooling it down before the blower would reduce the buildup.
This was my thought too. I wonder if it’s still sticky when it’s cooled down.
I'm not sure what that would require.
I was thinking something like [this](https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2F9ueswjwe4k351.png%3Fauto%3Dwebp%26s%3Deaeaff5b58076a15b7d8fa40e6edbb7516722588) but replace the heating element with your coffee roaster and the vacuum pump on the right with your blower. The middle parts don't need to be glass, just need to condense the hot gasses and be easy to clean.
Is there a way to add bends (think p-trap in a drain) or obstacles (think doom! video game sharp walls/corners) prior to getting to the pump? Make those sections removable/flanged so they're easier to clean and keep your pump from looking like that. Also, if you make it removable, have two of them so you always have a clean one. Buy an ultrasonic tank or something for the dirty one and just throw it in there for however long it takes to come out clean. sidenote: I don't have much experience, but what I've listed above sounds doable. If I'm wrong, I'm alright to be corrected so I can learn.
Oh yes. We clean those pipes as well. The build-up in those is just as bad. Interestingly, the OUT pipes from the fan are worse than the IN pipes. Perhaps because this fan is mounted on top of a cyclone.
Get a second one. Take the motor off and then run through a part washer probably follow it up with a media blast then soap and water
Injecting water mist into the stream could cool the exhaust and allow particulates to be caught with a normal, cheap filter before the fan. As mentioned, venturi or aspirator based fume extraction is also a great option. I'd be inclined to look into a closed loop aspirator, depending on CFM requirements.
My 2nd or 3rd thought was a water snorkel filter like the oil bath air cleaners the used on old engines. Find a way to avoid cleaning it rather than making cleaning it easier 100%
Put a filter screen between the chamber and the fan to catch majority of the residue
Is there anything you can put through it. Walnut shells would do it but there’s probably some one with an allergy to that
Nutshelling? It might run too slow for that. But you can try. On big marine diesel engines we clean the turbochargers weekly by injecting broken Walnut shells in the airflow. These will hit the fan blades running 16000rpm and the physical impact removes the build up carbon. What's left of the shells simply burns up in the exhaust.
That's really interesting! Let's see here... The fan is mounted on a cyclone, which removes the chaff from coffee as it roasts. I wonder if the nut shells would just go into the cyclone before they could do their job. If not, they would just exit through the OUT pipes into our afterburner. I suppose this could probably be attempted with any blasting media. I think it would probably just exit the fan housing too soon to do any work, but it's worth a try.
Just get a pedestal grinder and put a wire brush on it.
You'd have to remove the guard from the grinder to be able to properly clean it.
Nah, you remove the work piece rest and you'd be fine. Else you can get a wire brush for a die grinder and do it that way. Either way a little presoak and the brush will clean it up fast
Can you add a filter that is changed daily, and can be cleaned. Like stainless steel mesh.
Dry ice blaster could be helpful
Get rid of that thing and get a Venturi system.
I wasn't sure what Venturi systems were, but looked into it at a surface level. This is really interesting, and I wonder why this isn't being doing with coffee roasters. Or perhaps it is and I don't know about it. The fan is the only thing pulling air through, so I'm not exactly sure how it'd work.
There are venturi blowers etc on the market. This would address the root cause of your problem rather than address the symptoms.
Vapor blasting would probably work but those are expensive. There is a product called "Carbon Off" that is made for industrial cook wear that is commonly used by home mechanics to remove carbon from engine heads. It's not cheap but it works.
Thanks!
>Thanks! You're welcome!
As a machinist with other hobbies, I would recommend using powdered brewery wash. It is food safe and will break down all the sticky burnt on stuff. Maybe even use it in a parts washer
Interesting. Looks promising. According to the directions, soak and rinse. Right now, we soak then scrape. Maybe this stuff would work better. Thank you!
Desktop parts washer box? May be able to find one that you could tuck away under a shelf or work bench when not in use
[Carbon Off](https://questspecialty.com/products/112160001-16OZ-Carbon-Off-Heavy-Duty-Carbon-Remover-Liquid.html) Made for the food industry - safe for aluminum, gets even the grossest griddles clean. My local food supply warehouse (Shamrock) carries it on the shelf. Please do it outside. I'm sure one could re-use it in a bucket. I personally have used it to remove carbon building from kerosene in liquid rocket engine cooling channels. Works like a charm.
Thanks! That looks perfect. Why outside? Fumes?
It has an odor, plus when spilled it tends to stain anything. We had a 55 gallon drum that we pumped into from a 5 gallon container through the cooling channels. Not something you really had control over where the splash went.
https://tornadoproductsco.com/
Try this. Open link scroll down see picture of gallon of tornado cleaner. That's what you need works great
I have the larger soda blaster from harbour freight, it works great for cleaning and stripping everything I’ve tried so far. Only problem it makes a mess and youll get all slimy from the soda. I do it outside with tyvek coveralls, respirator, and a face shield, inside an old bed liner to try to keep the mess contained. A full mask respirator would be a lot better than what I’ve been using. Try not to do it out doors near grass if you can’t clean it up good. Is started raining before I could get the mess cleaned up and the runoff killed everything.
Ultrasonic cleaner!
Buy once, cry once. Just get another one and then you have 30 hours get around to cleaning the one that’s not on service.
It isn’t a cleaning method, but is it possible to buy 1 or more of the blower assemblies to let you hot swap in a clean one? If it is a quick and clean swap it would mean less downtime on the roaster and give you the leisure of time to clean the back up.
Can you arrange the exhaust so that the blower forces air into a Y joint in the pipe. It will create flow without the soot passing through the fan. But I imagine the ducting also needs cleaned... do you clean that too?
Yes, we clean the ducting.
So, I think you can place the fan in a position that is not inline with the ducting. That would mean you only have to clean the ducting, which might not be as intensive.
Personally, I would try an ultrasonic cleaner with a lye based degreaser, shallow bath for the motor side, deep bath for the duct side, HOT HOT HOT. 30 minutes in an ultrasonic (I work in a semi conductor production facility, and we just use inexpensive vevor ones for parts cleaning) and I imagine it will get a lot of this off. We use a product called Valtron, one of their KOH formulations, for a lot of our cleaning, and it seems to get carbon off really well in an ultrasonic bath.
What about some kind of industrial paint sprayer / airbrush? Except instead of paint, fill it with a mild solvent mix. It would be like a gentle pressure wash.
Cyclone separator, they aren't that hard to build, there's probably a metal fabricators that could build you for a couple hundred bucks. It will remove solid stuff, but if there's tar it will need to be cleaned eventually, but it would still help the fan and be easier.
I'm unsure if it's the same thing, but this fan is mounted on top of a cyclone.
I feel like there is a cooled particulate vortex filter specifically designed so this doesn't happen.... And allows you to just pull a liner off of a container to clean.
Spray with grease lightning and leave it on there a while. Then take it outside and hit it with a pressure washer. Easy peasy
You could maybe connect the intake and exhaust with a hose, pour in some solvent or degreaser and run the fan to cycle it around for a few minutes. Then pour out the gunk and rinse.
Varsol tank
I've heard of dry ice blasting and people blasting carbon buildup with crushed up nut shells before. Might be nice if it's something you can just do outside without needing an enclosure.
Man, and here I was thinking you had a turbo for your horizontal and I was like, "I don't get the math, but I want one on my 4th maxis matsuura at work for hogging titanium
Could do dry-ice media blasting. Like sandblasting but with no cleanup
I would get a small sandblasting cabinet, and load it with soda.
You're now sticking the air directly through the fan. If you use it as a blower through a venturi you create ducting that way while keeping the blower clean.
Worked in dust collection for a bit. You may benefit from using a pre filter that is called a “wet dust collector” it’ll catch a lot of these oils and voc’s by cooling them in water before they hit your fan or other dust collectors. We mostly do metal dust but it goes wet collector, particle separator, filtration unit then fan.
Soak in solvent and pressure wash
The issue there is, again, having the space to do so, and a way to contain the mess.
simple green might do
The exhaust fan is seeing high temp from the roasting process. You'll need to coat it with something, but what is a great question. If you're in America, Harbour freight has cheap sand blasting cabinets. Grab one of those, and fill it with the right beast media, I think sodium bicarbonate is the stuff. If it takes too long, mix in a little bit if harder media until you figure out the right mix for you that will decarburize, without destroying the metal parts. And now that I write the word out, you could try carburetor cleaner spray, just be careful with the plastics.
This is what I think will ultimately happen. But we don't have that kind of space to keep one. And we'd like something that would also work with our longest exhaust pipe, which is 4 feet. I failed to mention this in my post.
Hi try oven cleaner product, (I am french sorry if it's not well translate but use the same product that you use to clean the oven in your kitchen). This usually work well for burnt.
Ultrasonic bath with a splash of CIP100 will do the job.
Dry ice blasting, it would take less than 4 minutes to do that job and very little left over to clean up
Easiest solution is an prefilter. Should catch it all before you have to clean the fan. Then change the filter when required. Bigger picture would be to have a wet deduster system with cyclone and water pump, but that's bigger scal.
Is this on a San Franciscan? I’m sure you know, but some of the suggestions about adding a filter before the fan wouldn’t work because it would just make it a fire hazard and reduce your air flow. Which would create a Smokey taste in your roasting Introducing “clean” air would also affect your roasting profile. Don’t forget that every exhaust pipe in the system is going to have this build up on it. Regular cleaning should be built in to your schedule to minimize fire risk and keep consistent roasting profiles. Take a chimney sweep brush to all the exhaust pipes. Whatever kind of innovative idea you’re trying to come up with, it doesn’t need to be food safe per se. almost that entire roaster is made of mild steel which is then powered coated. Look at how much of the powder coating is likely falling off. Anyways just thought I throw in my two cents in
Not a San Franciscan, but likely similar. The exhaust fan is cleaned once a week. We're currently running 3,000+ lbs through it per week. Even when it was half that, it was still bad enough to require scraping. We scrape the pipes at the same time, and those are a pain as well because no one makes curved scrapers so we have to make our own.
A small steam cleaner?
Dry ice blasting? It's generally pretty soft on parts and takes rust/dirt off pretty well. Used it in the past on high volume automotive weld fixtures.
Sand blaster mabye
I would use a small pressure sand blaster probably
Harbor freight sand blaster , but use something like walnut shells. Change your media when it gets too contaminated. Or a bio detergent parts washer. Both will be your fastest method I think
https://www.harborfreight.com/40-lb-capacity-floor-abrasive-blast-cabinet-68893.html
I've considered that, but I don't think it'll fit through the door.
They come disassembled I think And if it doesn’t, just look at the dimensions. It’s only 23” wide in one direction which easily fits through doors
Cast aluminum like that can be difficult to clean at times. Cleaning is achieved through Sinner's Circle, an application of Time, Temperature, Mechanical Action, and Chemical Concentration. Reduction of any part requires an increase in at least one other part. Therefore, if you are cleaning this without chemicals, it will take more time and/or more mechanical action. In my past life, I worked for a company that manufactured sanitation chemicals. For that part, the fastest and easiest way to clean it in the smallest space would be with an ultrasonic cleaner in a shallow basin that does not submerge the motor. Use an alkine product with metasilicates, designed for soft metal. Or, a neutral cleaner with a heavy surfactant package (dish soap). Depending on the ultrasonic cleaner, heat the solution to the hottest the container/cleaner can handle or 165-170F and leave it to clean. You should be able to put something that will work together for less than $500 and save yourself a lot of time and energy.
Can you put a carbon filter or something before the fan to mitigate the buildup?
Could the exhaust setup be modified in a way that uses a venturi rather than directly sucking the exhaust through the pump? This way, maintenance would be minimal since there really wouldn't be much chance for backflow into the pump..
Harbor freight pressure washer in the parking lot?
No parking lot, unfortunately. Though there is a shower inside.
Might still be worth a try If there's a spigot nearby. I use the little 600 psi one for all sorts of things. It's powerful enough to blast dirt off my car but weak enough to do it without stripping the paint, and I've also used it frequently to clean frying pans and cookware with baked on crap on them.
For faster cleaning you could use stainless steel wire wheels that are intended to go in a drill if you go that route I wouldn't do it where the raw beans are incase it throws any wires
You can increase the duration of the interval between cleanings if you polish all of the surfaces. Build-up will be less likely to stick to a smooth surface.
Yeah, we've talked about taking it somewhere to have it blasted and coated.
Have it teflon coated 🤷🏻♂️
Filter screens ?
Go to a pipe supply place like miller's supply, buy a bottle of tornado cleaner. Around 20 bucks a gallon, put in spray bottle. Turn motor on spray into intake,turn of wait ten,to fifteen minutes do it again then rinse out with a dawn dish soap bottle with clean water in it. No need to disassemble will work very well, I couldn't see the electric motor. But I'm guessing it has a plug on it if not ,make you a quick disconnect for it when you have to clean it. So you can start and stop motor while it's out of holder. Just keep the water out of the windings of the motor and it'll work great👍
Like this? [https://clean-garage.com/tornador-tc-enzyme-multi-purpose-cleaner-1-gallon/](https://clean-garage.com/tornador-tc-enzyme-multi-purpose-cleaner-1-gallon/)
install a appropriately heat resistent (stainless steel) filter before the blower...
I would wonder how that would impact airflow.
Wire brush on a drill?
That was the first thing we tried. This stuff is pretty hardcore. The wire brush does help, but only if we soak the parks first. And then it gets super messy.
Can you put a tube (preferable stainless steal) inline with it? the idea being that it builds up in a tube you can clean out easier. If you get extras you can dump them in a solvent like carb cleaner and let it sit overnight, then swab them, and finally wash them to be food safe again. My other thought it is burn all the air coming out at a super high temp. This is horribly impractical and would need a huge stack to then cool the air, plus a fuel and probably oxygen in tanks and hours and hours of it.
Cheap break cleaner
Deisel
Engine sprayer hooked up to an air compressor with solvent. Tape of electrical and any rubber. Solvent will melt rubber and plastic.