I have already drilled a 20mm hole in position for an outside tap. I need to drill it out to 35mm to take the Frosti tap I have bought.

I cannot seem to find a 35mm Masonry drill bit that does not have an SDS fitting (it needs to be over 300mm long).

I don't own an SDS drill.

Can I buy a converter somewhere so I can fit an SDS ended drill bit to my standard hammer/non-hammer (non-SDS drill).

I see hundreds of adapters to fit a standard non-SDS ended drill bit into an SDS drill, but am yet to find one the other way around.

 

(PS I only need to drill one hole. I have already drilled through the two concrete block leafs at 20mm with no problem using my non-SDS drill at 20mm. So answers that say 'buy an SDS drill' are not helpful to me.)

It'll l fit in the chuck as is, no adapter needed. You might ruin the shank of the bit, but hardly a concern if it's once off use.

 

Be aware with a bit that big (I've never used over 25mm), it might be bit of a struggle, and there will be a lot of strain on your drill. A clutch is needed.

Edited June 27, 20251 yr by Conor

35mm is very big for any masonry bit. I would look for a cheap diamond core drill bit and set up a simple guide on the wall so its guided down the right line at the start. Normally you wouldn't need a guide but as you are just enlarging an existing hole I think it would be necessary 

Edited June 27, 20251 yr by Beau

you can, if your careful put SDS in a normal chuck...

 

and a cheap TCT core will do it

I have used SDS drill bits in a Makita hammer drill, not ideal but any port in the storm.

https://www.ukdrills.com/tct-core-drills-drill-bit?gad_source=1&gad_campaignid=981782100&gbraid=0AAAAAD8ijkek1n6oBt64G-lPT48MKUvMo&gclid=Cj0KCQjwgvnCBhCqARIsADBLZoI0K4MCYSL3UcSclQG1Z-G1Cp8HkHchhEbsZwJ3O_fkmR3HJ0bUwBUaAsOTEALw_wcB

 

One of those

 

Then a 22mm diamond drill arbour to a six-sided chuck adaptor

 

SDS or 'plain' in these kits, but ebay/amazon will sell individual bits I'm sure.

 

https://www.ukdrills.com/diamond-accessory-bits