Forstner bit advice for size needed.

[Raymond Fries]

I need a 26mm bit for some hinges. 26mm equals 1.02362". Can I use my 1" forstner bit to drill the cup hole? Or, will it be to tight of a fit?

Thanks

[Edwin Santos]

In a word, yes. It will likely be too tight by about 1/32".

A 26mm forstner bit on Amazon is about $10. https://www.amazon.com/CMT-537-260-31-Forstner-32-Inch-Diameter/dp/B000P4LLFE

I think you can get them at Rockler also.

[John K Jordan]

I need a 26mm bit for some hinges. 26mm equals 1.02362". Can I use my 1" forstner bit to drill the cup hole? Or, will it be to tight of a fit?

FWIW, I bought several Forstner bit sets recently including three metric sets. Although the bits themselves measured correctly, I found that the holes from nearly all of the bits measured larger than the size stated. Seems like the carbide sets were worse than the steel bits. Maybe some of it was due to the Dogwood I was using to test, don't know.

I THINK one of the sets has a 26mm bit. If so, I'd be glad to chuck it up and test the next time I walk down to the shop. I also have some 1" bits I could compare.

I did consider chucking up a bit and "surface grinding" it slightly undersized with a stone in a Dremel but I finally bought a bit that was much closer to the exact size I wanted. This is the bit that worked better (they probably have a 26mm size). https://www.amazon.com/gp/product/B000P4LLCM

JKJ

[Lee Schierer]

I've used my fraction sized bits for metric holes for hinge cups with no problems. They usually cut slightly larger than the actual diameter of the steel, depending upon what wood you are boring. Try a practice hole in a piece of scrap from the same wood to see how the hinge cup fits.

[Larry Frank]

For something like this, I would buy the right bit.

[Ken Fitzgerald]

I don't know if I have a Euro hinge like that in my shop anymore. I may have used them all but I will see if I do. Should I have one, I'll drill a hole with a 1" Forstner bit and see if the hinge fits.

[Ken Fitzgerald]

Sadly, the only Euro hinges I had in my shop required a 1 3/8" or 35mm hole. Sorry I wasn't any help.

[Bruce Page]

You could try it on a wood scrap and see. An old machinist trick is using a small shim under one jaw of the drill chuck (or collet) causing the cutter to rotate slightly out of concentricity. It works well with end mill cutters, should work with a Forstner bit.

My first choice would be the $10 bit from Amazon.

[John Lanciani]

Seems like it would be pretty simple to either drill a hole with the bit you have and measure it or just try the hinge and see if it fits, no?

[Raymond Fries]

Great tips guys and thanks for the offers. Well I have not ordered hinges yet. I was going to order the bit with the hinges if necessary. Looks like the best thing to do is drill the hole and measure. Wish I would have thought of that.

If it is a little tight, maybe I could drive it home with a hammer. LOL. Just kidding. I will buy the bit if necessary.

[John K Jordan]

If it is a little tight, maybe I could drive it home with a hammer. LOL. Just kidding. I will buy the bit if necessary.

YIKES! Oh, you were kidding. Maybe try a propane torch.

I have enlarged holes by hand with a knife and with a little sanding drum on a Dremel. Gently. :)

JKJ

[Raymond Fries]

Well, looks like I should just order the bit. My forstner bit drills a hole 1.003. The required hole is 1.02362.

Was just looking to avoid a tool for one project.

John - If the cabinet turns out like crap, I might use your torch idea. LOL.

Seriously, it will turn out just fine as I am pretty picky about my work.

Thanks again all for the feedback.