Flymo speed regulator

[Jonnyspeed]

Hi there. I have a 600w flymo and I need to control the speed of the fan. Looking around in maplin there is nothing and in RS uk they are expensive. Has anyone got any ideas where I could recycle one from. For example some hoovers have a dial which you can change the suction power with. Is there anything I might be able to find which isn't an ache to acquire. Was thinking possibly a dimmer switch but not sure. Any ideas?
Cheers
Jonny


Oh and it's 230v of course..

 

[ericmark]

Interesting idea. At the moment my lawn is under 4 foot of snow so don't think the flymo will really be required for some time.

I have never really looked at what type of motor was fitted. With a brushed motor relatively easy. But with a squirrel cage you need to change the frequency which means an inverter. The problem is the weight of the inverter would weigh down the mover.

The petrol does have a speed control and where one wants to change the cut height then petrol is the only way really of get rid of the hover. It's a lot less bother without the hover.

 

[Jonnyspeed]

My garden is getting there with the snow today as well!

So the motor has brushes I think, as there are 2 carbon blocks either side being pushed in by springs. What's the difference?
Unfortunately for the flymo i wont be using it for gardening any more. I'm trying to create a fume hood with variable speed. All to be tried and tested of course.

So is it possible to get this thing to change speed? I am thinking that the voltage would need to be the thing to be changed as the amps is a more complicated and possibly time consuming area.

What to do what to do....hmmm

P.s it's a leaf blower flymo

 

[Jonnyspeed]

So what can be recycled to work with the speed of the 600w motor?
Not a squirrel cage motor.
Single pole
600w
230v
All the regulators from china would take weeks. Even if they are £5 it's too long a time to wait.

Any ideas peeps?

 

[securespark]

Why do you want to do this?

 

[Robin0577]

Leaving aside the question of why.....

Assuming it's a simple universal brush motor, as most Flymos I've seen are, then a simple 1000w lighting dimmer should do the job.

E.g. http://www.tlc-direct.co.uk/Products/VL1000.html

Be aware however that on most models the fan is used to cool the motor as well as providing the hover function so the motor may well overheat if run too slowly.

 

[Jonnyspeed]

Noted Robin. I won't be messing with any of the casing luckily so the motor will be cooled as normal. Just going to rewire the switch to the dimmer and hey presto!
The only thing is I hope that the flymo has a high enough cfm. If not I have a 2500w leaf blower from screw fix to modify. Finding a regulator for that will be interesting...

Thankyou for your help.

 

[Robin0577]

One other point...

What kind of fumes?

Anything hot or corrosive may damage the motor.

Anything flammable like cellulose paint or thinners, petrol vapour, etc. - don't even think about using a brush motor!!!

 

[Jonnyspeed]

Not a problem as blow setting will be used. No fumes running anywhere near the motor and exhaust pipe sealed off to vent somewhere else. Otherwise, yes it would ignite.
Which type of motor were you thinking of that has less dangers to it?

 

[ericmark]

The enclosed squirrel cage motor often has an EEx rating and a high IP rating may be enough in some cases to ensure the mix level never reaches an explosive point.

The one I set up had overload and current switch so if it stalled the overload would trip and unless current was detected the PLC closed down the plant. There were two extractor motors which would alternate in use and auto change over if one failed.

I have worked in a few places where failure of extractors would auto shut down the plant. I have also worked on a re-ferb where this was not the case and the wall cladding was blown off when the dust ignited.

This is clearly not DIY work. I never did get my EEx certificate but realise that there are different rules. Oddly EEx and IP don't always go hand in hand with some EEx stuff not being fully sealed for water ingress.

The glands are also special in some cases with epoxy resin and are not like normal outdoor glands. I seem to remember made by a firm called Hawk fitted hundreds on a petrol chemical ship building and these are very easy to damage compromising the EEx rating. We used a special oil to ensure the digram was not damaged.

 

[bernardgreen]

I'm trying to create a fume hood with variable speed. All to be tried and tested of course.
~~~~~
P.s it's a leaf blower flymo
~~~~~~
Not a problem as blow setting will be used. No fumes running anywhere near the motor and exhaust pipe sealed off to vent somewhere else.

If you are blowing air into the hood you will be dispersing fumes into the work area around the hood. This is NOT the way a fume hood works and will be a hazard to the person working at the hood and also for other people in the room. Add to the explosive hazard the hazard of toxic affects in people breathing the dispersed fumes.

If this is a serious project then forget about re-cycling available and un-suitable equipment and invest in the correct extraction equipment.

 

[Simon35]

Not a problem as blow setting will be used. No fumes running anywhere near the motor and exhaust pipe sealed off to vent somewhere else. Otherwise, yes it would ignite.
Which type of motor were you thinking of that has less dangers to it?

Is this in commercial/industrial premises? If so, ATEX regulations apply. You cant just say there are no fumes anywhere near the motor. Dont know if they apply for domestic environments.

A lot of my work is in electrical controls for equipment in ATEX zoned areas. It is, without doubt, not a DIY job.

If you are slowing the motor down, the fan which cools the motor is also slowed down, the motor surface temperature goes over the atmosphere ignition temperature, or you get a spark, and you get an explosion and somebody is seriously injured because you have saved a few quid instead of doing it correctly.

http://www.hse.gov.uk/fireandexplosion/atex.htm

 

[Jonnyspeed]

There are certain criteria to be met for its intended use so I will achieve it I have no doubt. It's ok guys. Safety first n all.
Just because I am using the blow setting doesn't mean I'm blowing it into the hood btw.
And recycling is what we do nowadays. Most components in various appliances can be reused but instead we buy them newly packaged as something else.
Versatility is the future for us as these kind of websites become even more popular.
I am working on the possible motor cooling problem. But like I said there are no fumes near/passing the motor at any point.
Nor any spark near the exhaust.
Saving a few quid is what I'm doing and it will be done correctly.
Thanks for the link. And thankyou for your concern.
And godnight..

 

[bernardgreen]

Just because I am using the blow setting doesn't mean I'm blowing it into the hood btw.

So is it a pressurised room exhausting ONLY through the hood ?. That is a way to achieve a safe working area under the hood but only if the room is other wise air tight and doors are kept closed or are airlocks. I doubt a leaf blower could generate enough pressure in the room.

Unless of course you are planning to use the blower in a venturi effect vacuum generator. Could work if you get the design of the venturi right,

Saving a few quid is what I'm doing and it will be done correctly.

Good luck and if there is an accident lets hope the insurance and/or crime prosecution service have the same opinion about "correctly" as you have. Otherwise it could cost you a few hundred quid.

 

[bernardgreen]

I quoted my self instead of editing the post I wanted to edit. So I have removed my error.