Thread: Wow - huge price difference

Sounds like another good option Martin. What are you aiming it at?

Rob, with the computer fan, are you pushing the air through the motor or pulling it?
I'm looking the flywheels that were in the treadmills and i think there is enough meat there to machine one pulley, and then mount another outboard over the multi v pulley. this way i can keep the original fan and add another.

Hi Ewan,

I'm pulling the air through the motor from the (cleanish) drive belt enclosure at the pulley end and exhausting into the drip tray area.

If you go the other way you will probably get metal cuttings sucked into the motor which on a DC permanent magnet job is bad news.

You're right about the flywheels being good candidates for machining pulley "V's" into. My setup is pretty tight on space so I've left that option as a last resort.

V pulleys are pretty easy to machine. I made some up for a reduction gearbox and it was no problem if you use a narrow (35 degree) cutter to profile them.

I've ordered one of these to play with re the tacho.

eBay Australia: Buy new & used fashion, electronics & home d

Be interesting to see how it goes.

Where did you get your gadget from Martin ?

Cheers all

Rob

G'Day Fellas,
The sensor came from uxcell, it is aimed at a single slot sector disk mounted on the end of the spindle, If I was doing it again I would buy a tubular proximity sensor as I think it would be easier to mount and adjust. When they say working distance is 5mm they are not kidding, it is 5mm +/- a gnats nut, I still have to play with the Omron EE-Spy reflective sensor. I will probably stay with the Sick reflective sensor for the lathe, I'm playing with various sensors mainly to see what will be most suitable to fit a tacho to the RF31 and possibly the drill press (cant be stuffed opening covers to check belt positions).
Regards.
Martin

Originally Posted by toolman49

G'Day Fellas,
If I was doing it again I would buy a tubular proximity sensor as I think it would be easier to mount and adjust
Regards.
Martin

Is this the one your talking about Martin?

5-8mm Hall Effect Proximity Sensor Magnetic Switch DC 6-36V NPN NO 300mA | eBay

I looked at those and wondered if they would be fast enough?

Cheers

Rob

Originally Posted by Ueee

Sounds like another good option Martin. What are you aiming it at?

Rob, with the computer fan, are you pushing the air through the motor or pulling it?
I'm looking the flywheels that were in the treadmills and i think there is enough meat there to machine one pulley, and then mount another outboard over the multi v pulley. this way i can keep the original fan and add another.

Ewan if you add PC fans and retain the original one as well, when you reverse the motor the fans will fight against each other.

PC case fans only rotate in one direction.

Also check to see how the pulley is mounted as some screw on, and when you reverse the motor they can screw off.

My 2 HP motor has a plain shaft with a flat, not sure what the 1.5 HP has as I've just tossed it in the corner for now.

Rob

Hi Rob,
I'm sure i would have worked the fan thing out....eventually!

The pulley's are keyed and held on with a set screw, no worries about reversing. I'm really keen to get this up and running, the lathe only has a 3 amp peak, 1/2 hp on it at the moment and it's a bit gutless, plus the speeds it is set up with are a bit widely spaced and i have a habit of using only 2 speeds.....one for small stuff and one for large as the flat belt likes to slip on the smaller pulleys.

Hi Ewan,

What lathe do you have? Flat belt - must be a Hercus ? You might have belt slip problems with the extra HP. "V" belts next ?

BTW I spent the last couple of hours with that Hall switch mounted in the toolpost so I could finely adjust the position and various/many magnets mounted in/on my four jaw chuck and I tried everything to get that damn tacho to give a steady reading below 200 RPM.

No way. So that's it. Finito.

Good thing the pulley is keyed. Mine isn't. Some weird engineering in these treadmills. Some of it is really well thought out and heavy duty and other stuff is quite weak.

My 2 HP motor had a huge flat on the shaft and an absolutely puny little grub screw holding the original pulley. I made up a new cast iron pulley this arvo and it's got a good strong grub screw in it. A key would be better but there's no way this will move.

Cheers

Rob

G'Day Blokes, (& Blokesses)t7.JPGt8.JPG
Setup the Omron EE-SPY reflective sensor and am most impressed, dead stable, almost instant response, no need for a sector plate, just a bit of black electrical tape on the spindle,(will add a stripe of black paint eventually). Hookup dead easy, it needed a pullup resistor, the case is from Jaycar, cut in half so you get 2 for the $18.00. Total cost tacho $12.00, sensor $9.25, case $9.00. not bad for $30.00 all up. Have fun playing with your versions.
Regards,
Martin

Originally Posted by toolman49

G'Day Blokes, (& Blokesses)t7.JPGt8.JPG
Setup the Omron EE-SPY reflective sensor and am most impressed, dead stable, almost instant response, no need for a sector plate, just a bit of black electrical tape on the spindle,(will add a stripe of black paint eventually). Hookup dead easy, it needed a pullup resistor, the case is from Jaycar, cut in half so you get 2 for the $18.00. Total cost tacho $12.00, sensor $9.25, case $9.00. not bad for $30.00 all up. Have fun playing with your versions.
Regards,
Martin

Hi Toolman, Where did you get the sensor from.

G'Day,
It was from uxcell, if you go to the Omron website and download the data sheet you will see the various EE-SPY types with different mountings and outputs, Omron recommend you use their plug and cable, but I got away with soldering to the pins (heatsink and work fast with a small iron).
Regards,
Martin

what value is the pull-up resistor?

Hi Jack,
200 ohms was nearest to hand, works fine.
Regards,
Martin

Thanks Martin.

I'm going to give the HE sensors a miss. Sounds like they are too finicky. I'll order a EE-SPY optical sensor from uxcell and mount it in a similar place as you did.

Hi all,
Got my HE sensor in position today, just cable tied at the moment until i am 100% happy but it is working fine. I will put the tacho in the same box as the DC controller but i have to wait till i have the controller to know what size box to get.