[Nameless Drudge]

When looking around at gutter vacs there are some cheaper 3 x 1000W motor machines that have tops extremely similar to the top of the range sky vac,yet Sky Vac claim nearly 50% more suction I.e. 374 m/bar as opposed to what appear similar machines at 250 mbar.Is it the cyclonic entry!or super duper high torque motors that no one else has which i seem to feel i doubt.Anyone clued up with this or used the top of the range sky vac and found it massively better than anything they have had prior.I have had the omnivac 4200 and i've  had Kevin Martins and probably the omnivac has a bit more pull with 15m of hose and 40ft up but as ive never tried side by side it could just be wishful thinking justify the cost.Sold both but here i am again about to buy.Seems gutter vacuuming like wfp is now the norm! So ill probably source individual items,carbon fibre tubes being one supplier,Restoremate and another i cant remember for hose and possibly make my own head tools but i want the best vac to start with.Help welcomed,any thoughts,facts,thanks in advance.Maybe this could be a once and for all thread until new designs appear.

[Mike Halliday]

Vac power is an area very prone to exaggeration by manufactures , often it’s the max the vac motor will pull when fixed to a Table in a workshop,  not fitted in a machine sucking through 40ft of vacuum hose. And amount of air moved is not an indication of power,  a fan will move a massive amount of air but won’t create much suction.

I removed the head & fitted a 2;5inch outlet to this machine to make it into a gutter vac,  it has massive suction (meaning moved a lot of air ) but once it had to pull through a hose it was terrible....... it didn’t have the ‘torque’  it had the speed but not the power if that makes sense.

Gutter vaccing is not the great opportunity the manufacturers suggest, we still often get out the ladders

[Smudger]

you mean you can vc this sort of cr*p out of the gutter - shame on you !! 

[Mike Halliday]

My machine would grab that and hold it, it wouldn't Suck it down the pipe but it would suck on it so hard you could lift it out of the gutter.

I would put my ladder up at the end and feed my drain rods down the length of the gutter and pull it all back. Saves the chance of breaking any tiles by walking on that roof

[Nameless Drudge]

Anyone possess what they consider the highest torque vac?

[Mike Halliday]

When you say ‘torque’ you really mean mercury lift which is what they measure the force that a vacuum creates.

You have 2 options, a tangential/fan system or positive displacement rotors to create vacuum.

Most vacuum machines we see use a fan to create the suction, these machines scoop air out of the atmosphere and throw it out of a tube creating a back vacuum but once the scoop of the fan are full they cannot grab anymore air so have a limit to have much air they can move. Also if you block the inlet it  will spin in its own vortex (not pulling any air) which is why you should never let a vacuum seal on a surface,  it will no longer move air... so the usable suction stops. 

Or positive displacement (PDB)  if you look at the photo below you will see that these are a totally different category of vacuum creators,  fans are like 3 wheel Robin Reliants     PDB are   Like heavy good vehicles the metal rotors keep pulling air until something breaks,  either the vacuum tank inplodes , the engine stalls, the relief valve opens or the shafts snap.

 block the inlet and they keep pulling,  so create massive mounts of mercury lift. But they need a lot of power to rotate the rotors so normally use petrol or Diesel engines and they are cast steel so incredibly heaving. A gutter vacuum using a PDB would be the most powerful but not very portable.