diamond core drill bit for 4 inch fan holes

[Tris Zanker]

I'm going to buy my self a core bit for 4inch fan holes, what size do you guys have 107mm or 117mm and what makes are good?

 

[Hiddo]

I've got the set that Makita do. I've battered it and it just keeps going. A bit more expensive than some of the others but well worth it.

 

[Welchyboy]

I use 107mm, if you use the 117mm i find it's tricky getting fixings in the grill on the external wall

 

[Richard Burns]

I would go with 107mm as well. The cheap ones don't last long (but do work while they are OK).
Core bits tend to strain SDS drills, if you are building up start with using the SDS but consider a core drill when you can. (I haven't got one yet but have had to buy a new SDS!)

 

[sedgy34]

You probably won't need the set just the size you need
but get a core drill for it as sds will pack up

 

[blogs]

I've got the set that Makita do.

 

[PC Electrics]

If you're going to connect the outside grille with solid duct, then you can use 107mm. The duct will be a snug fit in the hole and as mentioned above there's more brick left for fixings.
If you're going to connect the grille with flexi tubing then you will need 117mm as the flexi won't fit through 107.

I use Norton bits which I get from Screwfix.

Make sure you are using a drill with a clutch release or you're likely to break your wrists off. I use a Bosch Pro DRE-26.

 

[Top Cat]

If you're going to connect the outside grille with solid duct, then you can use 107mm. The duct will be a snug fit in the hole and as mentioned above there's more brick left for fixings.
If you're going to connect the grille with flexi tubing then you will need 117mm as the flexi won't fit through 107.

I use Norton bits which I get from Screwfix.

Make sure you are using a drill with a clutch release or you're likely to break your wrists off. I use a Bosch Pro DRE-26.

It will if you twist it, put your hand inside it and gradually inch it forward grazing your knuckles while cursing the bl**dy thing and trying to stop it tearing! Apart from that. piece of p**.:wink_smile:

 

[mayfair]

Todays lesson ....speaking from experience, i guess, LOL. My wrist still aches from trying that about 2 years back. lesson learnt after about the fifth time.

Make sure you are using a drill with a clutch release or you're likely to break your wrists off. I use a Bosch Pro DRE-26.[/QUOTE]

 

[PC Electrics]

If you're going to connect the outside grille with solid duct, then you can use 107mm. The duct will be a snug fit in the hole and as mentioned above there's more brick left for fixings.

Further to this:
If you adhere the grille and tube together using conduit cement, you can drop a plumb line out of your hole and lift the grille/tube assembly up to the hole from the inside. Reach out through the hole and pull the tube through. Rotate to align the grille outside (or use a round one). Now fill round the tube with Stixall or similar. Voila, grille in place and no need for a ladder!

 

[GLENNSPARK]

norton or edge for cores.....hilti or makita for core drills.....

 

[Tris Zanker]

Thanks... i'm going to be using my sds drill for the time being as i've just brought a new van so moneys rather tight. think i'm going to get a 117mm one.

 

[Top Cat]

Thanks... i'm going to be using my sds drill for the time being as i've just brought a new van so moneys rather tight. think i'm going to get a 117mm one.

Still think that's the wrong choice but it's up to you.