Well, went to Tractor supply. All I could come up with is a 6 inch
pulley for the motor and a 2 inch pulley for the jointer. So I
currently have a 5 inch pulley, six inch pulley for the motor and a 2
inch pulley and a 2.5 inch pulley for the jointer.
So, My options are a 6 inch pulley on the motor and the stock 2.5 inch
pulley on the jointer for a total of 4176 rpm.
6 inch pulley on motor with new 2 inch pully on the jointer for 5220
5 inch pulley that came with the motor and new 2 inch pulley on the
jointer for 4350 rpm.
I think my manual said to shoot for 4400 rpm. I know the new model
jointers turn at 5000 though.
Here is a link to that page in my manual that talks about required
Which one should I use? Also, I dont have a guard ont he jointer. (Yet)
What is the risk of one of those knives flying out?
Probably not -- but 5220, as you said in your earlier post, is not just "a
little" faster. That's almost 20% faster. There is a possibility that the
knives will come out, if you spin the cutterhead that much faster than it was
designed for. Maybe only a small possibility, but a possibility just the same.
I apoligize in advance for being blunt almost to the point of rudeness, but I
have to say this:
God gave you a brain.
The manual calls for 4400. Your choices, according to your earlier post, are
4176, 4350, and 5220.
This does *not* require a whole lot of thought to figure out.
Doug Miller (alphageek at milmac dot com)
I don't think the guard is there to keep the knives from flying out and
hurting you; it's there to try to keep you from doing something silly and
sticking a consumable item (i.e. finger) in the sharp whirly danger area.
Given the number (and type) of questions you've been posting over the last
week or two, I'd advise getting a guard in place. Soon. Like, before you
hook power up to the thing.
As far as your question goes, I don't understand why you're even asking it.
The link you posted says "For best results the jointer should be operated at
approximately 4400 R.P.M." To me, 4350 is approximately 4400, and is
obviously your closest match. 5220 is not, and you'll be exceeding their
recommendation by about 20%. Considering the thing is old and in unknown
state, it seems foolish to me to consider doing that just because the modern
ones run faster. This isn't a modern jointer, and it didn't magically
become better built over the last few years.
BTW, you did confirm that the motor attached to your jointer is a 1725 rpm
motor, right? The manual link you posted suggests a 3450 rpm motor but
since the jointer appears to originally come without a motor, there's no
telling what's there without looking.
The motor is a 1740 rpm according to the plate.
I am asking for the rpm because I thought if it were a little faster it
might cut better. Also, I am not 100% sure the diameter of the jointer
small pulley I bought is the right one. I had not planed on buying one
for the jointer, just a 7 inch for the motor. but when I went to the
store 20 miles from my house they did not have a 7 inch. The largest
was 6. SO I figured I would also buy the 2 inch and take back the one
that would not work. So really my choices are 4100 rpm or 4350,
depending on what pulleys work.
My plan is to buy a guard off of a machine and try to make it work inmy
exisiting hole. I just dont like the way a plywood guard looks but that
is just me. Thought maybe making one out of metal but not sure about
Running faster means more cuts per second, which should mean a smoother
surface on the wood. But spinning things at higher than recommended rate is
dangerous. Centrifigual force, overheated bearings, etc. And since the
5220 rpm wasn't just a little faster, I sure wouldn't recommend it. If it
was the other way around, with a choice of 3600 rpm (800 less) or 4450, I'd
go with the 4450 and not worry about that.
As far as the guard goes, running without it is just seems silly, regardless
of what it looks like. Maybe if you had years of experience with them, and
knew the danger areas, it might be different. And metal, plastic, or wood
will all work just as well, I'd imagine. If it makes it look better, make
it out of MDF and paint it the same color as the jointer. Put some racing
stripes on it if you want better performance, and away you go. The nice
thing about a wood one is if you're off on the dimensions at all, and the
guard gets nicked by a blade, you won't damage your new blades.
faster cuts better sometimes; as long as the blades are nice and
sharp... if they are getting even just a little dull faster will burn
a plywood guard is a good start for any homemade guard. first, it gets
something there right away and for cheap- so you're covered for the
immediate. second, it lets you run the thing for a while before you
invest the time and cash making a metal one. once you've figured out
what works or doesn't, go ahead and make a final version from metal,
lexan, nice hardwood or what have you.
The answer to your question
Your questions have been answered at least twice in here
Your questions have been answered at least twice in rec.crafts.metalworking
Your questions heve been answered in the manual which you supplied a link to
Just incase you missed it
from the manual
For BEST results the jointer should be operated at APPROXIMATELY 4400 RPM.
Satisfactory operating power and speed may be attained by using a 1/2 horse
power 3450RPM motor equipped with a 2 1/2" diameter pulley.
Half the motor speed = twice the size pulley ... ie: 5"
What is does not say is what size pulley came from the factory on the
jointer. When I got it fromt he auction it had a 2.5 but I have no way
of knowing if the was what came o it stock or not.
Paul D wrote:
It doesn't matter. You know what sizes of pulleys you have to choose from,
what speeds they will produce at the cutterhead, and what speed you're
supposed to have at the cutterhead. That's all you need in order to figure out
which pulleys to use.
Doug Miller (alphageek at milmac dot com)
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