How do i drill a hole into a sink to fit a waste disposal unit. Fitting is too small

[Deleted member 1779]

[h=1]How do I drill a hole in a sink? [/h] [h=1]Can you tell me how to use a diamond core or holesaw or drill bit to drill a hole into a ceramic sink[/h]

Dear 365-Drills, I have a ceramic sink that I bought from IKEA and I wanted to fit a waste disposal unit instead of a standard waste trap. The problem is that the hole is too narrow. ​ Its 85mm and it needs to be 90mm. How do I drill a hole into a sink. How to I widen the hole into the sink so that the WDU fits. The whole kitchen has been built around the sink so its difficult to change the unit.

Model shown IKEA DOMSJÖ Sink bowl

Answer: At 365drills we have our own team of staff dedicated to drilling holes into ceramics and porcelains and we can come to site and do the work.

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[h=1][SIZE=+1]This is how we did it[/SIZE][/h] [h=1]

[/h] Shown first and above is the actual sink we will be drilling into

First we remove the sink from its fittings. A bit messy but no matter

Now we have to remove the tap

The sink is inspected for damage and photographed

All marks are noted and photographed (Note this is just dirt not scratches)

Our method: Take a look at the hole. You can see that it is well over 30mm thick (The maximum drill depth of the core) and it also contains the drainage ring from the overflow. Its essential that this channel be maintained so that the overflow can operate. Good news the increase from 85mm to 90mm will have a minimual impact on the centre drain ring. We are only going to remove 2.5mm of material.
The plan is to secure a clamp to the shiny side of the sink (top side - inside) and to drill to the centre of the drain chanel. The clamp will then be removed. We will then continue to drill through the sink using the top ring as our drill guide. That way we do not have to turn the sink upside down and meet the hole in the middle.

 

[Deleted member 1779]

Re: How do i drill a hole into a sink to fit a waste disposal unit. Fitting is too s

A note about the selected clamp: We have modified our clamp to get an exact 90mm fit by cutting out some fibre board with a jigsaw. The reason we did this is to ensure no error or slippage (movement) during the diamond drilling of the hole. The clamp is suction based and is useful in confined spaces on materials like shiny ceramic. We are guaranteed a tight seal. Drilling such a large hole and slipping would be a disaster so taking the extra precation of removing the top clamp (metal) and using wood is an additional security method.

The diamond core is introduced into the first hole (the top hole). Water is fed by the yellow sponge (seen just behind the diamond drill bit)

We squeeze the water sponge which releases a controlled flow under the clamp to the drill head

Close up view of the hole forming. Can you see the trench line being cut deep into the top hole

Top hole drilled and clamp is removed so that work can start on the second hole

The drill is placed GENTLY into the new 90mm hole. And slowly started.,

A real close up shot of the second hole forming. At this stage it is critical to grip the drill to stop it chinking or moving into the gap while rotating at speed. Any snatching movements could cause the china to snap, break or chip heavily and ruin a so far nice looking job.
The drill is stopped and water squeezed into the chanel you can see above by the sponge. To do this the drill is gently slowed down and allowed to come to a complete stop before removing it to allow water in (and photos to be taken)

 

[Deleted member 1779]

Re: How do i drill a hole into a sink to fit a waste disposal unit. Fitting is too s

Wider shot

And thats it - both holes have been drilled through

The water sponge is used to mop up

[SIZE=+2]JOB DONE ![/SIZE]

 

[Deleted member 1779]

Re: How do i drill a hole into a sink to fit a waste disposal unit. Fitting is too s

[SIZE=+3]Customer asked for EXTRA WORK[/SIZE]

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New brief: Customer very happy new hole drilled into ceramic sink at 90mm to allow the waste disposal unit to be fitted but now wants an EXTRA hole drilled for the switch. Luckily we carry all sizes.

Hole size required is 32mm. Customer marks area on sink unit (black dot) where she wants it

First we measure the central points for the exisitng tap hole.

Next we take measurements close to customers dot mark. We want to be within her request but also central to the main tap

With the ceramic sink marked up in a various pattern of ball point pen, marker pen and pencil the centre point is agreed apon.

The 32mm diamond core comes complete with an anti-slip guide plate. This prevents the diamond core from slipping on the very shiny white ceramic glaze. The plate is centralised and again all marking double checked. At this point its critical to make sure everything is accurate. Once started the hole can not be changed. As a precaution the sink is removed and turned upside down. The underbelly of the sink is checked for obstructions and castings. Its quite possible to drill a hole in the wrong area of a sink. So check it before you drill.

Step back from the sink and look at the layout. Does everything seem OK ?

Thats it. There is no going back from this point. Once the initial cut is started the installer is commited to creating the hole

First ten seconds of drilling the hole. The diamond core has been removed from the drilling to show the start. The milky subtance is the water mixed with ceramic dust

Even though there is no going back now the markings are wiped off and the hole checked again for accuracy.

 

[Deleted member 1779]

Re: How do i drill a hole into a sink to fit a waste disposal unit. Fitting is too s

In the sink is the bucket where we store a little water to cool the diamond core

The yellow anti-slip guide plate is removed. The diamond holesaw can sit into the pit and will not slip. From this point on the drilling is simple. Just keep it wet with the sponge. Diamond holesaws generate heat as the bit grinds into the material. Here you can see we have jammed the water cooling sponge up against the core bit delivering a constant feed of water. We do not need a forced water cooling system and arbor. All we need is this simple wet sponge. The diamond core is allowed to rotate into the pit and is its own guide through the ceramic sink.

The pit is now cut quite deep into the sink so you are at a critical moment. DO NOT MOVE THE DRILL. If you move the drills position the diamond core is likely to "kick" inside such a deep hole. Breath slowly and maintain a hard grip of the drill. What can happen if you do not have experience is that the diamond core bit will be running at speed and things will seem to be going well. But if you are not used to drilling at depth (say more than 10mm) then you can get quite a nasty mule kick from the drill if you move slightly. This is not exactly life or death for you the installer.... But it can snap, break, chip or split your hard done work. Even small surface chips can spoil a job that was going great. So be aware at this critical stage and just hang on. At some stage you may want to add more water by removing the core from the drill site. In this instance you can see we have removed the core to take a photo. Make sure that the drill comes to a gradual stop. And then gently pull back on the drill to remove the core. Rush nothing at this depth. Do what you need to do then put the diamond core back in gently and with ease. Dont force it or wiggle it. If it seems tight remove the core and start from a fresh angle. You are at your most critical at this point so extra care will get your reward of a perfect hole.

If you have been a patient installer. If you have followed the instructions, taken your time, used water and marked correctly then your hole will look as good if not better than the manufactuers. I am sorry I cant show you the fully finished installed items because the customer did not have them to hand. So we can only guess at the finished results. Always the way with many installations. But if you have done your job well then there should be satisfaction and pride in meeting your customers brief and perhaps more. Hope this blow by blow account is useful to installers asked to do such work but also the general public who search out online for explainations on how to achieve this sort of work. We get a lot of our work by people reading projects like this online and then calling with their own needs. We can come and drill and we have the tools and equipment but if its not us at the door then we can recommend many others who have used our PORSADRILL diamond core drills.