Drilling hole slightly larger than 3/4 inch

[JTTHECLOCKMAN]

Wrap a 5/8 dowel twice with self adhesive paper or regular paper with spray adhesive.  Just tight enough to go in and then rotate a few times.  I did this with game board sections that rotate on a dowel.

Why not a drum sander. Sneak up on it. How many do you need to drill??

[DieselDennis]

At work we had an old wore out drill press with a bad chuck. It would drill oversized holes perfectly even with a nominal bit.

Seriously, what are we dealing with here ? Is the 3/4" bit not going to get the job done?

[Peter Tremblay]

I am trying to drill holes in 3/4 inch plywood that are slightly larger than 3/4 inch. I start with a 3/4 inch Forstner bit, but my holes need to be .78 inch in diameter. How can I do that?

I know that old bits for bit braces were oversized by (I believe) a 1/32"

That might work.

Something like this #12 3/4" bit.

[jlanciani]

Lots of great ideas posted, too bad the OP hasn't even bothered to check back in yet.

[AgGEM]

Machinists boring head.
Make any size hole you want, within range.
Don't know what kind of tool or grind would work well in wood.
I imagine inexpensive ones can be found.

[daddo]

I have a range of paddle (Spade) bits I have customized for doweling or tapering holes- under sizing or over sizing holes. I even made a bit that drills two different hole sizes in one pass- like a step bit.
Grinding it even on both sides is the trick. Make marks precisely on the paddle where you want it, then drill practice holes and measure.

If you have a lot of run out on the drill press a paddle bit is much less precise as it may tend to ream the hole if the wood is very soft or the bit doesn't have the cutting ears on the outer part of the paddle.

[BloomingtonMike]

I am trying to drill holes in 3/4 inch plywood that are slightly larger than 3/4 inch. I start with a 3/4 inch Forstner bit, but my holes need to be .78 inch in diameter. How can I do that?

Jasper jig can do it. Or make a template with a 1/4" bit and strip with pin (make your own circle jig.

Use that either idea to make a 3/4" thick template, stick that to the spot where you need the .78 hole, then flush trim to the template after getting close.

[Splinter Puller]

Grinding it even on both sides is the trick.

I think its pretty easy if you have an accurate digital caliper. Find the difference between the original bit diameter and the target diameter.  Set caliper to original minus half the difference. Grind off half the difference from one side first using the caliper... reset caliper to original minus the full difference then grind off the remaining half difference off the other side.  It will end up perfectly centered.

[Timberwolf]

I am trying to drill holes in 3/4 inch plywood that are slightly larger than 3/4 inch. I start with a 3/4 inch Forstner bit, but my holes need to be .78 inch in diameter. How can I do that?

.........................
Use a 3/4" twist drill that is sharpened slightly off center and do not use a pilot hole.
Or turn down a length of sched 40 X 1/2" black iron pipe to .780" and sawcut teeth in one end...use it to saw your hole...If necessary, turn down a short piece if steel to insert into the cutter {braze it in} so you can hold it in your chuck to drill the plywood..

Item # Size Outside Diameter
SCH 40 Pipe-1/2 1/2 in 0.840 in

[AHill]

Might it be easier to take some sandpaper to the dowel or whatever device needs to fit in the hole?