Hello everyone,
I am not an electrical guy at all, however I am looking to solve a scenario which I am sure to one of you will be basic. I look forward to a reply in laymens terms please.
I make concrete castings from moulds. I use a simple orbital sander to vbrate the mould to get a nice smooth casting. The vibration at full tilt is somewhat too vigorous - can I slow this down with a gadget like they us in lights? A simple dimmer switch?
Thank you
Hans

 

You need a variable speed ac drive rated at say 400Watt to give a but of head room. Look at http://www.eurotherm.co.uk/products/drives/ac-drives. Then look on ebay.

 

Hello everyone,
I am not an electrical guy at all, however I am looking to solve a scenario which I am sure to one of you will be basic. I look forward to a reply in laymens terms please.
I make concrete castings from moulds. I use a simple orbital sander to vbrate the mould to get a nice smooth casting. The vibration at full tilt is somewhat too vigorous - can I slow this down with a gadget like they us in lights? A simple dimmer switch?
Thank you
Hans

It would be much easier to use a variable speed drill with some type of unbalanced "bit" that would cause it to vibrate.

 

You need a variable speed ac drive rated at say 400Watt to give a but of head room. Look at http://www.eurotherm.co.uk/products/drives/ac-drives. Then look on ebay.

Thank you for the information.
unfortunately in SA we are sort of excluded from ebay as the postage costs of sending would be prohibitive.

 

It would be much easier to use a variable speed drill with some type of unbalanced "bit" that would cause it to vibrate.

excellent idea thank you - seems the easier way.

 

I use a Variac to control power tools on the lower current spectrum (like drills and dremel tools). Mine is limited to 10A but im sure larger ones are available. A Variac is essentially a variable transformer. 120VAC goes in, 0-140ish VAC comes out.

Im thinking if the device is 200W @ 120VAC then it cant be more than a couple amps.

 

I would try the light dimmer. It's only $5, and it's pretty much what is in a variable speed drill anyway. Start at full speed. If all seems ok, back it down to about 75%, let it run a bit, and assuming the motor slows down, see if either the dimmer or the motor are oveheating. The dimmer should be warm to the touch, but not burning hot.

ak

 

I use a Variac to control power tools on the lower current spectrum (like drills and dremel tools). Mine is limited to 10A but im sure larger ones are available. A Variac is essentially a variable transformer. 120VAC goes in, 0-140ish VAC comes out.

Im thinking if the device is 200W @ 120VAC then it cant be more than a couple amps.

thank yo

I would try the light dimmer. It's only $5, and it's pretty much what is in a variable speed drill anyway. Start at full speed. If all seems ok, back it down to about 75%, let it run a bit, and assuming the motor slows down, see if either the dimmer or the motor are oveheating. The dimmer should be warm to the touch, but not burning hot.

ak

u, that's what I was hpopeing for - We run 220V in RSA. At an electrical wholesaler I found a plug socket with a "Dimmer" knob - going to get it and see if it will work.
Regards

 

Hello everyone,
I am not an electrical guy at all, however I am looking to solve a scenario which I am sure to one of you will be basic. I look forward to a reply in laymens terms please.
I make concrete castings from moulds. I use a simple orbital sander to vbrate the mould to get a nice smooth casting. The vibration at full tilt is somewhat too vigorous - can I slow this down with a gadget like they us in lights? A simple dimmer switch?
Thank you
Hans

As long as the motor has brushes, you can take the edge off the power by putting a diode in series with its supply.

Use a 1N5408 for 230VAC, or at least a 1N5404 for 120VAC.

Wire it in the mains side of any filter components to give the diode some chance against back emf and arcing at the brushes.

 

As long as the motor has brushes, you can take the edge off the power by putting a diode in series with its supply.

Use a 1N5408 for 230VAC, or at least a 1N5404 for 120VAC.

Wire it in the mains side of any filter components to give the diode some chance against back emf and arcing at the brushes.

Thank you for the interest

 

I would try as AnalogKid suggested in post #7. We used a similar vibration method for settling wet epoxy and the vibrator was driven by a simple SCR Light Dimmer control rated for 1,000 watts. Worked just fine. Depends on your motor but worth a shot.

Ron