Toothed pully design - Formulae

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No -No - bloody - N0 -This whole thread is falling to pieces

It's quite simple. All the info is in present books. There is no need for
fancy sin, cosine, advanced nuclear physics etc, etc.
In Smokes example below all the figures are OK EXCEPT he calls the answer
the PD, -- it's not. It's the OD. The PD is the figure before you take the
constant off.

Looking at this last night It's very easy to take all this info and put it
into a very simple spreadsheet.

So that all you need to do is input

[A] The pitch of the belt and
[B] The number of teeth required

That's all. - What you get out will be:

[1] Outside diameter
[2] Angle of cutter
[3] Width of cutter tip
[4] Distance to feed cutter in.

What more do you need ? You don't even need the pitch diameter.
If somebody can't take a blank , turn it down to a given size, grind a
simple flycutter up, mount it and feed it into the blank a given distance
then they should either be buying pulley's or not reading this list.

I can put one together either later tonight or possibly tomorrow night if
there is a demand for one. Something like an Excel sheet to cover the
smaller sizes like MP @ 0.080", XL @ 0.200", L @0.375" and H @0.500"
Would that suit everybody. ??


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> From: "Smoke" <Smoke@...>
>Subject: Re: Re: Toothed pully design information needed.
>
>Based on what the Browning catalog I have shows, we were right the first
>time. Number of teeth x pitch per tooth divided by PI - constant = PD.
>The constant for 3/8" pitch belts is .03, for 1/5" belts
>it's .02", for 1/2" its .054", for 7/8" its .11" and so on.

.

>To get the tooth flange angle I'd suggest doing it like Ian says...get a
>belt (or a pulley preferably) and measure the angle. That info isn't in the
>catalog.
>
>Smoke

--

Regards,
John Stevenson
Nottingham, England