# Step Pulley 1970 Bridgeport VFD RPM?.



## Janderso (Apr 13, 2018)

I need help. I am learning all about milling on the Bridgeport. I want to know what rpm I am running for the material, tooling size etc.
Please see my pics. With the step pulleys and the variable speeds I don’t know what the vfd display represents. 
Looks like we have a Teco fm360.
Thanks for the help.


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## dlane (Apr 13, 2018)

I have one of these https://www.zapals.com/digital-non-contact-laser-photo-tachometer.html may be cheeper on amazon 
Although I don’t use it all the time , I’ll go by chip load mostly


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## Janderso (Apr 13, 2018)

Are you kidding me?
I knew they had those for temperatures but I didn't know they made an rpm gadget.
Well that solves this problem.
Do you just point and read?
Are there magnetic strips to glue on?


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## will.mcray (Apr 13, 2018)

I have a product from this company http://servoproductsco.com/ for my Bridgeport Clone.  I replaced the 3 hp single phase motor to a 5 hp 3 phase, VFD with digital RPM display and control. Its a sweet set up.


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## ThunderDog (Apr 13, 2018)

I have the exact same one as dlane.

When I setup my Sheldon with VFD it did not have a speed chart.  Slapped the little sticker on the spindle, fired up the machine, scanned the sticker with the tach. Wrote down the speeds, done.


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## dlane (Apr 13, 2018)

Just a shiny piece of tape on a dull spinning surface about a inch or two away , but as stated I measure the chips usually


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## Janderso (Apr 13, 2018)

Sweeeeeeet, I ordered one from Amazon-Proime


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## dlane (Apr 13, 2018)

I also use a teco vfd, at 60hz should be close to speed listed on mill. I installed a remote with for/rev start stop and a speed pot


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## Janderso (Apr 13, 2018)

That is very nice! Clean too.


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## Janderso (Apr 18, 2018)

My gadget is now set up. Rpm by the push of a button.
I love this forum.


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