# RPM Requirements for a Honey Extractor



## BeeAttitudes (Dec 6, 2014)

I'm surprised this isn't commonly known. 

If you have an extractor and could read the RPM of the motor and give me the pulley sizes or, if gears, the number of teeth on the gears.......I can figure out the rest.


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## Rader Sidetrack (Nov 30, 2011)

I think you should look for a variable speed capability, so its not as simple as a fixed speed motor and some gear/pulley ratios. See my and others' comments in this similar thread: 
http://www.beesource.com/forums/showthread.php?313797-RPM-for-extractor

A DC motor and its variable speed control system scrounged from an unwanted treadmill is one option. Note that _some _treadmills have an AC induction motor (fixed speed) and a mechanical variable speed pulley drive system. I'd keep looking til I found a DC variable speed treadmill. A tool like IFTTT can be useful for monitoring Craigslist for whatever you want.


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## BeeAttitudes (Dec 6, 2014)

Yeah, I will use variable speed. But I think I will be better off gearing down near the max RPM to increase the RPM of the motor where it likely runs cooler. A max RPM will also give me an idea how much balance will be an issue.

I happen to have a motor on-hand so I was planning to use it with a router speed controller.

Did an Internet search and read one guy state that 180 RPM is about max without damaging frames/comb but I didn't see if that was for a radial or tangential extractor. He stated start around 60 RPM (1 revolution per sec) and finish around 180 RPM (3 revolutions per second). Another opinion was about 400 RPM. Hmmm, I wonder if that was for a radial extractor?


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## Rader Sidetrack (Nov 30, 2011)

You really can't separate the RPMs from the size of the rotating reel. What is important is the 'inches/feet per minute' that the _outer edge_ of the reel travels, so RPM is not particularly meaningful unless the size of the spinning reel is also specified.

Here is a Lega extractor spec sheet that has a motor that fits various different models, and the spec says 'maximum rotation 480 RPM'.

http://www.legaitaly.com/images/stories/virtuemart/product/GAMMA S700 S850_3.pdf
(English language version starts on pg 6)


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## BeeAttitudes (Dec 6, 2014)

Thanks for the link Radar. If you will read my first post, I asked not only for RPM but also diameter of the extractor.......so I think I'm on top of the physics in play. It appears I'll need to spin a radial extractor significantly faster than a tangential extractor. I hoped someone might have info on the speed needed for their diameter extractor so I would know how to ideally gear the one I'm making. With the difference in frame weights, 400 RPM is significant.


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## McBee7 (Dec 25, 2013)

I realize some of these statements will be relitive but,,,,2 of my friends have some realy OLD extractors and they have a single speed 1/2 hp motor 1750 rpm motors with a 2 inch pully on the motor and a 10 inch pully on the reel for a 5 to 1 ratio (350 reel rpm) and they do just fine spinning out 4 tangentel frames....I don't know the exact diameter of the reel but these old extractors are larger than the modern day units...They start out slow, with all the weight of the honey spinning but as they progress they speed up as the frames get lighter...I personally have a 9 frame radial extractor, hand crank, and my 10 year old grandson can spin it fast enough to throw out the foundation on deeps (3) spun tangentally...I realize this is a mix of known values and relitivisms but maybe it will help...I have toyed with motoring my extractor and just decided when I really really really need to motorize it I'll buy a new one 

==McBee7==


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## Roland (Dec 14, 2008)

Off the top off my head, I am building a 90 frame extractor with about a 65" reel, that will spin 180 RPM max.

The real test is too spin until they explode, and back off 25 percent.

Crazy Roland


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## BeeAttitudes (Dec 6, 2014)

Thank you Roland and McBee7 for your helpful replies.

Roland, if "reel" means diameter, then spinning 180 RPM with a radius of 32.5" gives a centrifugal force of 65.9 lbf (per pound of weight). Said another way, the centrifugal force is equivalent to 29.9 Gs (G being the force of gravity).

In my case, the inside diameter of the food grade plastic barrel I purchased is 22.5". So if I build a carriage that allows 3/8" clearance around the perimeter, the diameter would be 21 3/4" which is a radius of 10.875". To obtain an equivalent centrifugal force I would need to spin the carriage at 311.5 RPM.

My motor, unfortunately, turns a fairly high RPM at 3,450 RPM. So if I geared it down roughly 10:1 that would give me a max RPM of 345 which would be close. I seen info from SNL that stated much above 375 RPM and the frames may come apart. Using Roland's rule of backing off 25%, if we assume 400 RPM is where the frames come apart, backing off 25% puts us at 300 RPM. This puts me in the ball park for max rotational speed for a 21.5" - 22" diameter carriage. 

Thanks everyone for your input and help!


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## jwcarlson (Feb 14, 2014)

BeeAttitudes said:


> Thank you Roland and McBee7 for your helpful replies.
> 
> Roland, if "reel" means diameter, then spinning 180 RPM with a radius of 32.5" gives a centrifugal force of 65.9 lbf (per pound of weight). Said another way, the centrifugal force is equivalent to 29.9 Gs (G being the force of gravity).
> 
> ...


I read this post and thought: "This guy has to be an engineer."
Checked your profile, and sure enough... 

Let us know how it goes. I have a two frame hand cranker that my grandpa had decades ago. I think I may be interested in eventually adding a motor to it to save my arm (at least until my kids are old enough to spin it). I'll be interested to know your findings.


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## tanksbees (Jun 16, 2014)

A real engineer would spec out a 3 phase gearmotor with a VFD. DC motors and AC single phase motors are junk.

Something like this would be perfect for an extractor:
http://store.kgpowersystems.com/GHM...M-60-Hz.aspx?gclid=COzdpoD7o8YCFUhgfgodnBACJg

Teco makes an inexpensive VFD that can overspeed the motor if desired as well. I use one on my lathe.
http://www.ebay.com/itm/1-HP-115V-1...H1-/361252340238?_trksid=p2141725.m3641.l6368


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## BeeAttitudes (Dec 6, 2014)

tanksbees said:


> A real engineer would spec out a 3 phase gearmotor with a VFD. DC motors and AC single phase motors are junk.
> 
> Something like this would be perfect for an extractor:
> http://store.kgpowersystems.com/GHM...M-60-Hz.aspx?gclid=COzdpoD7o8YCFUhgfgodnBACJg
> ...


Of course you are right about 3-phase motors being better........but I don't have 3 phase at home <smile>. And 110V motors are cheap and plenty good enough for 4 - 10 hives which is likely all I'll ever have at home.


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## BeeAttitudes (Dec 6, 2014)

If I build this and it works fine, I'll just tell folks to design a radial extractor to spin fast enough to pull 30 Gs.


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## tanksbees (Jun 16, 2014)

BeeAttitudes said:


> Of course you are right about 3-phase motors being better........but I don't have 3 phase at home <smile>. And 110V motors are cheap and plenty good enough for 4 - 10 hives which is likely all I'll ever have at home.


That's the beauty of this, the VFD turns single phase 115V into 3 phase 230V, at any frequency you want, and spins up the motor at a predefined rate. So no jerky abrupt starts. And thermal overload/current protection if the machine stalls. With a silky smooth silent and reliable 3 phase motor

Come on, don't leave us all hanging building some cheap dinky extractor, man up and drop some cash on something we can all drool over.


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## marshmasterpat (Jun 26, 2013)

Curious question from a smash and strainer that is drooling over the idea of an extractor. 

Can you get most the honey out the comb with less than this optimum speed of a similar sized extractor (radius) at say 200 RPMs? 

Just curious, not sure that my idea will reach 200 RPMs using my ideas.


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## ian_m (Feb 5, 2015)

To those who can wait.. yes.


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## Roland (Dec 14, 2008)

What HP are you looking to use? I believe KEP has a 110 in, 220 3 phase out inverter that is fairly cheap. 

Do it right and do it once.

Yes, 30 g's sounds right.

Crazy Roland


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## BeeAttitudes (Dec 6, 2014)

marshmasterpat said:


> Curious question from a smash and strainer that is drooling over the idea of an extractor.
> 
> Can you get most the honey out the comb with less than this optimum speed of a similar sized extractor (radius) at say 200 RPMs?
> 
> Just curious, not sure that my idea will reach 200 RPMs using my ideas.


I can't answer your question unfortunately. However, it appears the honey comes out of the comb at a much lower RPM in the tangential configuration compared to the radial configuration. So I would think 180 RPM would be fine for a tangential extractor is it's in the 20" - 22" diameter ball park.


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## marshmasterpat (Jun 26, 2013)

Hmmm, well do tangential extractors break up more comb. Especially if you are using foundationless. ??


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## BeeAttitudes (Dec 6, 2014)

No experience, but my understanding is yes, you can damage comb easily in the tangential configuration. When the comb is first inserted it is full of honey. And when you start spinning the honey on the outside tends to be slung out of the comb.......but the honey in the cells on the inside of the frame is being slung into the comb. So if you go too fast too early, the force of the honey in the inside cells being slung outward can exceed what the wax comb can hold and the comb come apart. So most folks go slowly at first to remove most of the honey from the cells on the outside surface of the comb then stop and flip the frame over and then go slowly to remove most of the honey from the other side. After most of the honey is out you can start speeding up as there is less force pushing on the wax comb.


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## jwcarlson (Feb 14, 2014)

tanksbees said:


> A real engineer would spec out a 3 phase gearmotor with a VFD. DC motors and AC single phase motors are junk.
> 
> Something like this would be perfect for an extractor:
> http://store.kgpowersystems.com/GHM...M-60-Hz.aspx?gclid=COzdpoD7o8YCFUhgfgodnBACJg
> ...


I real engineer would do the project reliably, to budget, and not overbuild the application.

VFD, 3-phase where no feed exists... DC motors "junk"? Please.


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## tanksbees (Jun 16, 2014)

jwcarlson said:


> I real engineer would do the project reliably, to budget, and not overbuild the application.
> 
> VFD, 3-phase where no feed exists... DC motors "junk"? Please.


I stand by those statements.

The VFD is an off the shelf product that handles the 115V to 3 phase 230V conversion, is reversible, built in speed control, built in thermal protection, built in overload protection, braking. All for $150. Try and cobble together a speed control for a DC motor for that price that does even half that. 

The motor I listed is definitely overkill and expensive because it is a gearmotor, not because it is 3 phase. DC gearmotors are about the same price. Three phase motors don't usually cost more than single phase/dc for the same size.

You could do a pulley reduction with a motor but it will require more fabrication. Maybe $100 for motor, $100 for pulley/belt/tensioner system, and then $200 in time to fabricate? Cost depends on a lot of things. Not a huge savings in my book.

Finding a used 3 phase gearmotor and pairing it with a VFD basically makes the whole project easy, and it will be reliable, and long lasting, and not spark and catch fire in a few years when the chinese motor brushes start sparking. It's a better investment to buy high quality used equipment than junky new equipment.

Gearmotor is better than normal motor for this application.
3 phase + VFD is better than DC + junky speed control for this application.

The two concepts are separate.


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## bdillard (May 11, 2015)

Tanks bees is absolutely correct.

https://youtu.be/aSLZ1XKehno


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## marshmasterpat (Jun 26, 2013)

Tank or bdillard - I am another ignorant as a rock about electricity, but do these VFD 3 phase motors require 3 phase to run. I am assuming so, but wanted to double check. Or does the VFD convert 1 or 2 phase to 3 phase voltage?:scratch:

Edit - Watched the video and answered my concerns. It shifts 1 phase to 3 phase in the converter. Sweet.


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## Roland (Dec 14, 2008)

Most inverters(VFD) can be used with single phase input, 3 phase output, but MAY need to be derated. I run numerous pieces of metal and woodworking equipment with single phase input with no problems. The soft start ability is much easier on the gearboxes.

Crazy Roland


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## ATScuba (Jun 12, 2012)

Hi - Just as an update to anyone that may be looking for information on the original post - RPMs for Radial extractor: I built and ran a motorized extractor late this summer - The OD of the reel is 18" - Holds 6 medium or shallow frames (no provision for deep, cannot fit as radial on this diameter)

I built using a motor/gearbox that was onhand, leftover from another project - and with an inverter drive I was topping out at 245 RPM - this was sufficient to extract the frames, but I would run them for about 5 minutes at this speed to try and dry them out as much as possible - I will be modifying and retesting next year to see if 300+ RPM makes shorter work of this

I put an RPM indicator on this unit - knowing that I would want some additional information on it - and found that 80-100 RPM was a good starting point depending on frame weights - and then spin up to 140 RPM for about 2 min - then 180/1min, 220/1min - and top out at 245/5min

Between uncapping and changing out frames - I was processing 6 frames in 15 min - 24 frames an hour - I only had 100 frames - so it was a little over 4 hours to extract - which is way better than the 2 frame tangential that I was using


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## marshmasterpat (Jun 26, 2013)

ATS - good info, thanks for sharing


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## Harley Craig (Sep 18, 2012)

BeeAttitudes said:


> Thinking of building a honey extractor and I'm wondering how fast I need to spin the assembly to remove honey using a radial configuration. I guess the RPM required would be realtive to the diameter of the assembly that is spinning. I'll likely use a food grade plastic barrel so roughly 22" - 23" diameter. So what RPM will I need? If you have a radial extractor that works well and you know the max RPM and the diameter, let me know and I can convert that to the RPM required for the diameter I'll be using.
> 
> Appreciate any input.
> 
> Thanks!


I made my own with a food grade trash can, used a variable router speed controler, don't know the RPM but it works great https://www.youtube.com/watch?v=fM1oMJu4a70


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## aiannar974 (Mar 29, 2017)

Beeattitudes - did you finish the unit? Any pics of videos? Would love to see details including basket design


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