Widening 1" hole to 1.5" ??

[Sid Manly]

I wasnt quite sure where to post this. But I have a countertop from IKEA im using as a desk and I was wondering how I would be able to open up a 1" grommet hole up to 1.5" without chewing up the surface. I've tried a hole-saw in the passed, but without the pilot bit, it walks and eats up the surface bad. 

 

[TVwazhere]

4 minutes ago, Sid Manly said:

I wasnt quite sure where to post this. But I have a countertop from IKEA im using as a desk and I was wondering how I would be able to open up a 1" grommet hole up to 1.5" without chewing up the surface. I've tried a hole-saw in the passed, but without the pilot bit, it walks and eats up the surface bad. 

Start at a slight angle to build a groove, the rotate slowly 360 to build the rest of the guide groove. 

[Derrk]

get a step drill bit. i've only seen them get as wide as 1 3/8 inch but im sure they have them up to 1 1/2 inch

or just a 1 1/2 inch drill bit

[Sid Manly]

14 minutes ago, TVwazhere said:

Start at a slight angle to build a groove, the rotate slowly 360 to build the rest of the guide groove. 

Might have to try this. I tried it but it bit into the desk so hard it just murdered the surface. Do you think manually rotating the bit with a ratchet would work to just make maybe a 1/16th deep groove?

 

[W-L]

8 hours ago, Sid Manly said:

I wasnt quite sure where to post this. But I have a countertop from IKEA im using as a desk and I was wondering how I would be able to open up a 1" grommet hole up to 1.5" without chewing up the surface. I've tried a hole-saw in the passed, but without the pilot bit, it walks and eats up the surface bad. 

Since there is an existing hole as you said without a pilot it will be more difficult but if you are steady and go slow you can start a groove to get it going. A good trick is to take a scrap piece of material and to drill a 1.5" hole then use that as a template to clamp to the desk surface as a guide for the hole saw.

 

 

[SansVarnic]

@Sid Manly

 

Step drill bits past 1 1/8 inch are quite expensive, but they do make them and I do not suggest this;

$133 USD

https://www.amazon.com/MAGBIT-851-1500-MAG851-4-Inch-Diameter/dp/B005M27CGG/ref=sr_1_4?crid=X7CGMARE0QYV&keywords=1.5+inch+step+drill+bit&qid=1576562719&sprefix=step+drill+bit+1.5%2Caps%2C195&sr=8-4

 

 

My best and strongest suggestion is to use a hole saw, this is a by far cheaper and quicker solution.

Secure the panel to a piece of wood, make a center for the center bit and use the wood to guide the hole saw. (I was carpenter for a number of years, this works)  

[Lady Fitzgerald]

I

7 hours ago, SansVarnic said:

My best and strongest suggestion is to use a hole saw, this is a by far cheaper and quicker solution.

Secure the panel to a piece of wood, make a center for the center bit and use the wood to guide the hole saw. (I was carpenter for a number of years, this works)  

I also agree (I was a cabinet maker for a few years...seriously; I also have had some machine shop training and experience). However, good bi-metal hole saws and a mandrel, if you don't already one (cheap hole saws will dull quickly; Lenox and Milwaukee are good brands but stay away from Morse), cost more than one or two good halfround files. There's only 1/4" of thin sheet metal to remove around the perimeter of the 1" hole to go to 1/2" and you wouldn't be wasting time and dealing with the frustration of trying to secure a wood or sheet metal panel over the existing hole. Frankly, I would go with one or two 6" to 8" files (a bastard to hog out the metal quickly and a double cut mill file to clean up the edges although just a mill bastard would also get the job done; it would just take a bit longer).