How to make a 42mm hole in chipboard?

[pfb]

I need to make holes in a 12mm particle board to install downlights. The holes should be 42mm. What's the easiest way to make such holes? My first thought was a hole saw. However, I've only found 41 and 44mm, one of those could potentially work. Another idea was to use a jigsaw, but isn't 42mm too narrow for a jigsaw (don't have the world's best saw)...? Other suggestions? Could an adjustable hole cutter work? Like http://www.jula.se/stallbar-haltagare-125088

 

[bränski]

I would have taken the hole saw that is closest at hand, if it needs to be made a little bigger, do it manually... dremel/sandpaper...

 

[magnu]

Luna has a for metal 3339-2507. But it looked expensive and considering what Luna usually charges, it certainly won't be cheap.

If I remember correctly, the edge finish is not very important, there is usually an edge that covers the hole edge.

Therefore, I recommend that you use a compass to draw a 42mm hole on the chipboard.
Drill out with a 41mm hole saw.
Then the rasp and file are excellent tools. Remember that files can become dull. If you are unsure about the sharpness of the files - buy new ones.

 

[BigGitt]

I use the one from Jula. Works ok.

 

[ByggareNick]

42.5 mm cylinder drill, 0.5 mm shouldn't make a difference.
http://www.clasohlson.se/Product/Product.aspx?id=56106793

Otherwise, there are adjustable drills. (I doubt it's good)
http://www.clasohlson.se/Product/Product.aspx?id=133326412

 

[KnockOnWood]

If you drill the center hole a bit large (8 instead of 6.5 mm) and "wobble" the hole saw a bit during sawing, you'll get a slightly larger hole than the nominal 41 mm.

Wobble = don't drill straight down, but move the drill around in a circle. Results in a larger hole.

You often get larger holes than nominal when using the hole saw with a hand drill due to vibrations. Completely different from drilling with a pillar drill.

Test drill on a scrap piece and measure the hole diameter, and you'll see.

Hope you understand.

//KoW

 

[ziddhartha]

Have installed some various spotlights. The hole's dimension is usually generously sized by the supplier. Choose the hole saw with the next smallest size.

 

[pfb]

Thank you for the responses. I borrowed a 44mm hole saw, but it ended up being too loose. I wanted to avoid going to Jula or Biltema or any other store in Tornby, so instead, I used that cylinder drill from Klasse. Worked great, but wow did it make a mess! Thanks for the tip!

 

[Richtmann]

The best is to take the closest underneath you find, then if the hole is not big enough, a rasp is most suitable to make the hole larger with. But it worked out for you anyway