6.5hp gas engine, band size and speed ideas please

[fallenoak]

Hi Guys

just won a 2000w generator with a 6.5hp petrol engine in it for £33 on ebay. I know its not huge but yesterday i only had a 3hp engine to work with and now ive got another 3.5 horses locked in the shed.

any ideas on band speed (slowish im guessing) and band sizes?

Thanks

Sam

[beenthere]

Fallenoak
Might help to keep your bandmill build in one thread so your goal and the questions and answers tie themselves together. Just a suggestion for train of thoughts.  ;)

[Herb Brooks]

Hate to be a spoiler, but the generator engine probably has a tapered shaft.

[Mark W]

Hi Fallenoak
I am down south of you it has taken me 8 weeks to get my build all sorted out, and I have not started building anything yet. As Herb has said the shaft might be tapered, are you planning on using a clutch ? IF i am correct I think the band speed should be around 55mph but someone should correct me if I am wrong.
If you know the rpm of the engine and the size of your band wheels you should be able to work it out as to what gearing you need. Man there are lots of things that you need to get sorted just take your time and put pen to paper and get a plan down that will work. I hope your build goes well and I will be following it closely.

Mark

[Herb Brooks]

While riding my hour long commute I was considering the tapered shaft delema.  I believe the electric clutch from an older ford piston type a/c compressor is a York with a taper.  Further research my prove me wrong. But I will try.

[Herb Brooks]

Check here. http://www.classicautoair.com/FORD_OEM_Compressor_Parts.html   Taper may be different but a call to them after you get your motor separated from the gen set and measured they should be able to tell you if the clutch will fit.

[fallenoak]

Thanks for the heads up Herb atleast i now know what options ive got.

1)track down a clutch that accepts a tapered shaft
2)buy or make a shaft adaptor
3) peak output for the genny is 2.4kw so maybe i could run a 2.5 or 3 hp electric motor and still have a working genny for all those other mobile power requirements that pop up
4)sell the genny hopefully for a profit and buy a more suitable engine

only after a hobby mill for now so im just looking for the ability to cut your average tree a bit quicker than my chainsaw mill will 61cc 20" bar

anyone have any other ideas?

mark i was planning on having it chain driven to minimise power loss which i think would require a clutch but maybe i could go with some kind of bellt drive and tension the belt with another pulley when i want to cut?

not sure im still in the very early stages of planning as you may have guessed

good luck with your build ill keep an eye on what your up to if your posting details?

[Mark W]

I would be looking at a Noran clutch if I was you. If you Google Broardbent Drives their in Bradford, they have all the information you will need, not sure about the chain drive with all the dust !! I will be using a belt drive. they might have one for a tapered shaft.

Mark

[Verticaltrx]

I have a small bandsaw mill made by Hudson (model HFE-21) that uses a 6.5hp engine. It works fine for a mill with a 21" log capacity. The mill uses 16" band wheels and a 132" blade. The driven pulley is the band wheel which is 16" diameter, and the motor uses a centrifugal clutch which has a fairly small 1.5-2" pulley, RPM on the motor is about 3500.

Hope some of this info will help in your calculations.

[fallenoak]

im thinking maybe canibalise the gen set as there is obviously a matching female taper on there and maybe just bolt the two together

or maybe weld a sprocket to the female taper from the gen set making sure its well supported to drive my bandwheels. then rig up the engine on a sliding mount so that the two tapers can be brought together or seperated as a kind of clutch.

i know this might not be an ideal solution but it would mean i dont have to buy a clutch

any thoughts

sam

[fallenoak]

verticaltrx are you sure on that drive pulley size or engine rpm??? as a 2" pulley driving a 16" at 3500 rpm would give a band speed of 1832 surface feet per minute.

at 3500rpm driving a 16" wheel
a 3" pulley would be 2748 SFPM
a 4" 3663 SFPM
and a 5" 4579 SFPM

just wanted to confirm

sam

[Verticaltrx]

Just looked in the manual, the pulley on the clutch is actually 2.5" dia, band wheel is 16" as stated and engine rpm is between 3500-3600rpm.

Hope this helps

[Joe Hillmann]

Just looked in the manual, the pulley on the clutch is actually 2.5" dia, band wheel is 16" as stated and engine rpm is between 3500-3600rpm.

Hope this helps

Where does the belt ride on the band wheel?  Directly on the wheel? Or on a separate smaller pulley?