Max. diameter cut on softwood with hand drill?

[spader]

What is the max. diameter of holes hand / manually cranked pillar drills can manage? I was trying to cut a tea light hole on a pine board with a 42mm forstner drill bit using hand cranked vintage pillar drill, but it wouldn't do it. The bit was stuck in the wood about 2mm deep, and wouldn't go any further.

Do I need powerful electric drill for this job?

 

[magicmushroom666]

A holesaw that only cuts around the diameter of the hole will reduce the cutting pressure a lot, I'd try that first? The Forstner bit turns the whole thing to sawdust which is a big ask at 42mm!

 

[blup]

With a forstner bit, use an electric drill, in a drill stand for safety and accuracy. Use a holesaw only if you are using the full depth of the timber and covering the base.

Blup

 

[Deleted member 174758]

What is the max. diameter of holes hand / manually cranked pillar drills can manage? I was trying to cut a tea light hole on a pine board with a 42mm forstner drill bit using hand cranked vintage pillar drill, but it wouldn't do it. The bit was stuck in the wood about 2mm deep, and wouldn't go any further.

I thought you already knew that those things were designed for small diameter holes not honking great bits

Do I need powerful electric drill for this job?

Did you know that powered pedestal drills were in use by the 1840s (overhead line shafting and flappy belt drive) and electric powered drills became very common in the 1920s and 30s? So the idea of a Victorian factory using a small bench top hand cranked drill to drill 40mm+ holes seems just a nonesense.

But you don't need power tools. With a 10in sweep ratchet brace I can drill hole comfortably up to 25mm in softwood - with a 14in sweep brace I can do 38mm (the largest size of auger bit I have) with a bit of effort.

A 42mm Forstner probably doesn't require that much power to drive it, maybe 1/3 to 1/2HP, but it does need to run at low speed (200 to 500rpm) and requires quite a lot of torque, something power drills aren't good at. This points to a electrically-powered pillar drill as opposed to a hand power drill, which is likely to be quite dangerous in the wrong hands with such a large Forstner bit. Spade bits are available up to at least 40mm and they can even be run in a decent size cordless drill, but the cutting action is very different to a Forstner bit, being more of a scraoping action which requires a relatively high speed to work

 

[^woody^]

Was the bit actually sharp? A sharp bit should be able to cut the wood fibres no problem.

A cheap chinese randomly ground bit may not though

 

[spader]

I saw a youtuber who was using hand cranked pillar drill cutting large holes using forstner bits quite easily. Not sure if they were special forstner bits or would it be the pillar drill which make difference.

 

[Deleted member 174758]

For big holes right angle drills are now on the production line....
And have been for some time.

Those are for side drilling joists. Not much use for accurate square drilling holes

I saw a youtuber who was using hand cranked pillar drill cutting large holes using forstner bits quite easily. Not sure if they were special forstner bits or would it be the pillar drill which make difference.

They aren't special Forstner bits, but they aren't blunt, poorly sharpened TiN coated Chinese carp ones, either. Those cheap ones really can only be driven with a power drill and are notorious for clogging. Good ones are very expensive (look for Fisch or Famag and you'll see the prices) but even they can clog from time to time

The ability to drill holes is down to how sharp/well ground a bit is, the feed speed and the rotational speed. Why not ask the guy who posted the video what he uses? Stavros is a well known hand plane maker and user of hand tools

 

[foxhole]

Have used these in drill for large diameter holes .

 

[opps]

A holesaw that only cuts around the diameter of the hole will reduce the cutting pressure a lot, I'd try that first? The Forstner bit turns the whole thing to sawdust which is a big ask at 42mm!

Surely a hole saw is only useful if the OP wants to drill all the way through the timber? My understanding is that they want a rebated hole.

 

[opps]

Surely an 18v cordless drill should be more than adequate? I have never had any problems cutting 35mm holes with an 18v.

As an aside, is there not a potential problem with heat transfer from the base of the tea lights? I have never used them so I have no idea how hot they get.

 

[spader]

I have a small electric pillar drill as well. Once it was cutting 42mm hole on pine board, it was struggling kept stopping in the middle of cutting in depth of about 10mm. So I tried my vintage hand cranked pillar drill, and it wouldn't even start stuck at 1mm depth. I wasn't sure if it would be able to cut that size or not. But having seen the youtube video, I thought if the forstner bit is very sharp, it may be able to cut. But maybe 42mm is too much to ask to hand cranked vintage pillar drill. My forstner bit is not very sharp, and is a cheap make - no make bought from Amazon for maybe a fiver.

I might need more powerful drill, or sharper drill bits for the task, I wondered. My 18V Bosch hand drill may be able to cut it? I haven't tried it with it yet.

 

[Deleted member 174758]

Power drills will work better with blunt bits. I can directly contrast using auger bits in a brace at home with using power auger bits in a drill at work. At work ifcthe auger bits are a bit blunt I can still still holes whereas a bluny auger bit in a brace has no chance

The cheap Chinese Forstner bits I've tried are terrible things - blunt out of the packet, poor quality steel (so if you do sharpen then they go blunt quickly), and clog repeatedly - so you have to use a lot of pressure to get them to drill and you are forever withdrawing them to clear out the waste.