Thread: Hose for hand held power tools

Originally Posted by snowyskiesau

I've looked at some one supplies but can't really tell what the hose type is - it seems to be the corrugated PVC used for pools, or cheap Shop Vac's - it;s what was on my vacuum cleaner.

Any recommendations as to type of hose and supplier?

I experimented with the corrugated pool hose. (Threw the pool out but kept the pump/filter and hose) Don't bother. It whistled and screamed like a banshee as the air was drawn through it.
The rubber connectors are good for attaching to the tools though.
Let us know what you find because I am still looking for a better solution than my short length of very old vacuum cleaner hose.

Depending on the sucking power of your VC you don't have to use with 38 mm hose, you can usually go to 50 mm without too much of a problem.
Then you can get the smooth internal walled stuff with the corrugations on the outside which is quiet and flows a bit better than the corrugated stuff.

The rationale is as follows

Clean VCs typically have flow rates of around 75 cfm when uncluttered by a tool and around 50 cfm when there is a tool attached to them.

At 50 cfm the linear air speed inside a
- 38 mm hose will on average be ~4000 fpm, - which is a nominal minimum to keep sawdust suspended in the air stream and this is why 38 mm hoses are used on many VCs
- 50 mm hose will on average be ~2365 fpm so it may suffer from sawdust drop out restricting the size of the hose. Eventually some sort of balance will be achieved whereby the narrowing of the hose will increase the air speed and this prevents more sawdust dropping out. However if sudden jolt or movement of a hose loosens a pile of sawdust laying in the hose it can block the hose completely.

To maintain an unblocked 50 mm line all you have to do is every now and then uncouple the 50 mm hose from the tool which allows the hose to draw its 75 CFM.
At these flow rates the 50 mm hose now has an air speed of 3550 fpm which is usually enough to clear the hose.

This also depends on the VC not losing air speed due to filter blockage which can be reduced by using a chip catcher.

The 50mm hose is a pain to try and use with a hand held tool.
I'd thought I'd stand a better chance of finding suitable adaptors if the hose diameter was closer to the dust port size.

Still, I've a few rolls of tape so might give it a go tomorrow.

I use normal vac hoes with adaptors and a bit of foam tape and duct tape up to 4 inch on the dusty end,at the other end to connect to the hand held tools, mine are bosch and I seached around at bunnies in the poly pipe bins and found fittings that went inside the vac hose and fitted into the bosch outlets without any tape etc.
As BobL said this restricts the flow and every now and then I crack apart at the 4 inch connection and let things run for a while.
This has worked good for me for quite a few years,you just have to put your mind in gear to marry all the connections together.

I use the festooll 36mm hose for the sanders etc but use the 50mm hose for the mitre saw and the domino

Works well

Originally Posted by snowyskiesau

The 50mm hose is a pain to try and use with a hand held tool.
I'd thought I'd stand a better chance of finding suitable adaptors if the hose diameter was closer to the dust port size.
Still, I've a few rolls of tape so might give it a go tomorrow.

It depends where the work is being done.

"In the field" so to speak I agree the bigger hoses are very awkward.

If the work is being done on a bench then I reckon working with the hose handing down from the celing is a much better way to go. I do this by stringing a wire or plastic pipe across the ceiling with loops of wire and/or bungee cord hanging down to support the hose the weight of the hose is taken up and away from the floor and the bench. Even just one loop of drop down makes all the difference even with narrower Festool hose. This was the simple setup I rigged up at my friends place.



At home I use two or 3 loops depending on how big the piece I am working on is.

When it is done this way I barely notice the difference between the 38 and 50 mm hose and it's even surprisingly manageable with 100 mm hose.

I've had a bit of luck with cutting a few inches of bike inner tube and stretching it over the hose fitting and the tool dust port. Not perfect, but works pretty well. There's a range of different sizes available. The bike shops just chuck the tubes away, so go and make friends and ask for a couple of dud tubes.

Trav

over the years I have managed to buy large dia vac hose ( by the metre) from Rapidclean ( Newcastle) and the assoc. end fittings. (no affiliation , just good service)

No guarantee they still sell it now, but worth a call. It can be very expensive to buy if sourced from the 'wrong' place.

hope this helps.