Fan reducer

[Bahco]

Is there such a beast as a fan reducer from 150mm to 100mm.

I've seen 125 - 100 but not what I am looking for.

 

[Chri5]

TLC do 150mm - 125mm then add in the 125mm - 100mm one you've found ?

 

[333rocky333]

sure is

http://cart.vacuumsdirect.co.uk/index.php?p=product&id=179&parent=34

Google 150 100 spiral reducer

 

[Taylortwocities]

Here. It isn't difficult

 

[Spark123]

I'm wondering what effect using a reducer will have on ventillation having seen some of them kill the airflow.

 

[Bahco]

I'm wondering what effect using a reducer will have on ventillation having seen some of them kill the airflow.

Good question.

Does anyone know the answer?

 

[Taylortwocities]

We don't know if the fan is 150mm and the duct is 100mm or the other way round!

Do we remember what assume makes?

 

[Spark123]

Wouldn't that be an enlarger then

 

[Taylortwocities]

You silly boy. Don't you know anything?

THIS is an enlarger

Untitled

• Taylortwocities
• 12 Feb 2010
• 1

 

[Bahco]

We don't know if the fan is 150mm and the duct is 100mm or the other way round!

The fan is 150 mm.

As I have a 110 mm core drill it would make life a lot easier if I can reduce down to a 100 mm duct. This will depend on if anyone knows how the reduction will affect airflow.

 

[Spark123]

You silly boy. Don't you know anything?

THIS is an enlarger

Untitled

• Taylortwocities
• 12 Feb 2010
• 1

Is that something off willy wonkas chocolate factory?

 

[Taylortwocities]

This will depend on if anyone knows how the reduction will affect airflow.

Of course it will restrict the airflow.

My maths ain't that good after all the Merlot I've had but lets play some numbers:
Using πr²
A 100mm² hole has an area of 7855mm²
A 150mm² hole has an area of 17662mm²

So you'll only get 44% of the air through assuming its free air and no restrictions to the flow input. That will be a huge loss in efficiency.

Better to buy/hire/borrow a 150mm core bit.