Thanks Dan A for the real teck type calculating, i will try this out next time working on the chunker gearing. and make a note of this when i can.thanks
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i got an 8 too 1 gear box. the motor is 3400 rpm the flywheel is 22 inches acrost.? then what…?
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How many rpm do you want the output of the gearbox to turn?
The gear reduction of 8 to 1 means that if you directly couple the motor to the gearbox the output would spin at 425 rpm.
The circumstances is the diameter × π
In this case 22 x 3.14 = 69.11 inches
So you need to calculate out the ratio of the desired rpm over the directly connected 425 rpm of the drive pulley circumference to the flywheel circumference. That will allow you to calculate the diameter of the pulley based on the circumference.
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Hi dan i am a disaster at math, i want about 50 rpms at the cutting wheel, i have 8 too 1 ratio gear box and 22" pulley on the gear box, Thanks PS I get the 425 calulation from 3400 rpms ÷ 8 too 1 gear box ratio = 425, checking your notes. So after that calculation Does this mean a 2.75 pulley and a 22" pulley ÷ = 8 ÷425=53.1 RPM. ? Thanks.
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Using the ratio of the speeds vs circumference
T = target speed = 50 rpm
D = direct coupled speed = 425 rpm
F = flywheel circumference = 22 * 3.14
P = pulley circumference
Ratio of the two
T/D = P/F
P = (T*F) / D
The circumference ration will determine the gear reduction because it is the actual distance traveled by the belt around both shafts.
When I do the calculations I get a diameter of 2.598 for 50 rpm so yes I would agree 2.5 to 2.75 would get you where you want to be.
Someone better at mechanical engineering could probably argue with my approach but it should be reasonably accurate.
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Kevin, I’m not arguing with @DanNH’s calculations at all, but keep @Wayne’s suggestion in mind. Trimming down the first half of the cutting edge will also give you more time to feed the beast. I know I would hate the chunker to be too slow. Just saying.
Happy chunki’n
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I tried to show the math so someone could adjust it for any speed they wanted. But I do agree you can get equipment to be frustratingly slow as well as dangerously fast.
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Good Morning Kevin.
Very important that you are comfortable while chunking . My rig is designed to be sitting or standing. If you notice the padding at the the end of the truck spring . If I rest my
left arm it makes me more stable and chunking a lot easier, sitting or standing.
Also I am right handed and the chunker is set up for right hand feed. ( right hand feed for short sticks )
This video will show the rpm I like to run and having plenty of time to feed the beast. Two cyl tractor just idling .
Each time the wife makes a scoop of this hickory it is worth about a half gallon of gasoline 
Be very careful !! Until you learn the tricks the wood can pinch your fingers .
Have wood will travel
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Wayne, the more we advance in time, and the more we cultivate methods of efficiency to spend less energy and be the best performer possible, a thing reversed at the beginning of our lives, we do abort work the muscles before the brain.
Wayne, we note that you had a dazzling form on the video.
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Good morning Wayne K thanks for the speed of chunking vidio, and the music too relax too, Makes a good excuse for a work out, And good use of time and energy, used. Not Sure who made the song though, hadent heard that one except here at DOW.? Thanks for the Quallity wood gasifier plans and the vidios wood gas driveing and related.
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Hello Kevin .
The reason for the song and the noise of the chunker is not for any type of entertainment but to keep a rhythm . Feeding the chunker is like the game jump rope but a hell of lot more dangerous !!
The song on the video is a prison chain gang working on the rail road driving spikes . Two hammers on the same spike has to have rhythm .
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Well two is better than one in proper order, in unified team as noted. After checking Dan Allerds calculation tips and the speed of your chunker mine is turning about 85 rpms at the cutter, even then missing about half the revs too cut i was getting barrel of wood in 45 minuts, time for me too line up a smaller pulley too slow mine down about 25 rpm or 25 less turns a minut.Thanks. P.S Yes i remember that prizon song from tv shows now.You have your chunker idleing about 60 rpms in that vidio speed, looks fast enough THANKS.
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THANKS wayne for the finger pinch warning , i allready found a few spots not too hold your hands while loading the cutting wheel, if my wood splitter peg gaurd getts in the way, i will have too remove the splitting peg from the backer plate, and the gaurd, and split the wood elseware. i have a remote splitter made in the background about 4 pics from here, i havent tryed yet, just a frame with a plate wedge on top too slam the slab wood on, i may have too add more wedge and a table top under the wedge it it works any good, made it out of junk steel spit seem light ibeem type steel.
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remolt wood splitter working good, needs a platform plate under the wedge too catch the two halfs of the split peices.
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Found a minimum pulley size chart too match belt size and types. For instance the cheaper L4 and L5 fhp light duty belts will work better on smaller pulley than the clasicle type L4 or L5 belts that are rapped on outer near the surface with cords or kevlar. Them classic type belts Like larger pulleys too not be as ap too slip.C type belts are 7/8" wide, and are most all classicle type belts rapped in kevlar and in the medium duty rateing.
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You should look into the flat serpentine belts that use a grooved small pulley. Wrecking yard should have them and get the spring tensioner for a first class system
I am using a 2 1/2” pulley to drive my chunker
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Thanks Mike,i was going too,except all i had was a 1"-1/16" wide alternator pulley 2-3/4" accrost, then i thought there seems too be way more selection from v belts from all the years of industry. Then how would i get a alternator pulley true strait on a motor pulley, no true stait threads too tighten down the pulley, So i will stick with v belts, and add too my collection of lawn mower belts. since i just bought a classic type 5/8" v belt for a single addjustable type pulley, i will see how my gearing works for chunking speed. And then if my 3" single pulley slips too much i will add a reduction shaft and use bigger pulleys too get the speed adjustments wanted. I just redone the math correct i think. I devide my 22" gearbox pulley by my 4.25" motor pulley, Then devide that number by the 3600 rpm motor speed. Then devide that number by the gear box ratio that is 8. And i come out too 86 rpms. actually i could make that speed work with smoothing up the entrance too the cutting wheel guild area.And cutting the wood that has been split too 2 too 3" slabs. Would save some chunking time. See how i can manage the 3" pulley speed once the belt gets here for now.
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Helo Mike Gibb how would you get a serpentine car alternator pulley strait on a eleectric motor pulley.was my main reason too go v belts, as i had some pulleys too get started. The serpentines sure have the advantage in smaller pulley useage. I will stay with v belts for now and run them till no work anymore, and weigh the cost effect, or go serpentine later on perhaps.
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Thanks for the link , though like most of them serpentine pulley outfits no speak english, i caint find a 3" od 5/8" BORE and about 1-1/4" wide range on whith. Gess i have too call or email them, thanks for link.
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