Forstner vs Spade for veneer?

[Floyd Cox]

Will Forstner bits work to drill through veneer glued to plywood or do I need to use a spade bit to help prevent tear out?
Holes are 1/4“& 1/2“
This is for the face for the clock in May 2019 wood magazine

Thank you

407105

[Ted Calver]

I would sandwich/clamp the piece tightly between two sacrificial boards and use a forstner bit to drill the holes through the sacrificial pieces.

[Jim Becker]

What Ted said. You could use a spade with the "sandwich" but you'll want the type that has the scoring cutters at the edge to get a cleaner cut from that particular type of bit. But I typically use Forstner.

[Floyd Cox]

Thank you guys for the help

[andy bessette]

A Forstner or Fuller bit should do a clean job without the need to first go through a sacrificial piece. A backer is necessary though to avoid breakout on the backside. I would never consider a spade bit for 1/4" holes in veneer.

[Floyd Cox]

Thank you.

[Richard Coers]

Unless the spade bit has spurs, it will blow up the veneer.

[Chris Fournier]

A spade bit is for construction not woodworking. I've done both and even then a spade bit is the last choice.

[Zachary Hoyt]

It may depend on the quality of the bit in question. For holes that small I would prefer a brad point drill, but for bigger ones I prefer Forstner bits because they seem to have less runout. Maybe there are quality spade bits in existence, but I have not encountered them myself.
Zach

[Lee Schierer]

For zero tear out use the method Ted suggested with the finish piece sandwiched between sacrificial pieces either Brad point or Forstner bit will work best.

[Randy Benway]

Hi Floyd,
I must disagree with just about everything you've been told. I'm a retired wood patternmaker. Drilling a hole on size, on location, with decent finish is critical. When fabricating wood patterns and core boxes, everything was drilled then pinned with precision ground steel pins. It was MANDATORY that you had tooling that bored accurate holes. We all had Forster bits as well.... they were INVENTED 100 years ago for pattern work.

I suspect the drill bit that others are advising you to use is actually a multi-spur bit. The name Forster bit and Multi-spur bit have somehow become interchangeable now-a-days. THEY'RE NOT! They are two different animals and they behave totally different. It seems every type of drill for wood is being marketed as a Forster bit. This is a true Forster bit:

407225

Note the sharpened but smooth rim and small center spur. The Forster doesn't require the center spur to be engaged in the wood to remain on-axis. Forster bits do ONE thing well: they HOG STOCK like nobody's business! Patternmakers would use a Forster bit to hog stock away before going to a wood mill or over-arm router to profile a shape. The old guys had 2 or 3 of them in their Gerstner... sets are worthless. They are the WORST at boring holes. The small center spur makes drilling on center very difficult. They require high tool pressure so can only be used in a drill press. That high tool pressure also means MASSIVE BLOWOUT when exiting a hole. That's not what they are designed for.
This is a multi-spur bit:

407226

Multi-spur bits typically have a larger center spur that make drilling to a center line reasonable. They require less tool pressure so can be used in a hand drill. They definitely require the center spur to remain engaged or they'll 'spit out' the work piece fairly quickly. They leave a reasonably good finish but will also cause blow-out... you need to drill from both sides and meet in the middle to avoid blowout.

You mentioned your application is boring 1/4" and 1/2" holes. In that size, you can't beat a standard 118 deg drill bit. I own many brad-point drills (even a full set of Cleveland brand from 1/8"-1"...frightenly expensive 35 years ago) they all bore slightly oversize, are difficult to sharpen, and leave an average finish. Brad points also REQUIRE that you bore from both sides to avoid blowout. Brad points don't like end grain either. Patternmakers all used standard 118 deg drill bits when it counted. They are easy to sharpen, require low tool pressure, loves end grain, and leaves a good finish. As stated before, just use a piece of scrap as a backup and you'll get good results. Hope this helps! Randy

[Floyd Cox]

Randy, thank you for this information. Just for my curiosity, I'll do some test drilling with all three that were suggested. In the machinist bits for this size hole I'm assuming they need to run at a high speed?

[andy bessette]

...
I suspect the drill bit that others are advising you to use is actually a multi-spur bit... This is a true Forster bit:...sets are worthless. They are the WORST at boring holes. The small center spur makes drilling on center very difficult. They require high tool pressure so can only be used in a drill press. That high tool pressure also means MASSIVE BLOWOUT when exiting a hole...you can't beat a standard 118 deg drill bit... Brad points also REQUIRE that you bore from both sides to avoid blowout...

Randy--most of your post is simply wrong, despite your claimed vast experience. It's Forstner bits we referred to, not Forster. Sets are imperative, just like other types of bits (I have 2 sets). The center spur is absolutely necessary. They can in fact easily be used in a drill motor. 118-degree twist drills will badly chip out the surface of the wooden workpiece unless a sacrificial top piece is used. Brad point drills don't blow out the far side if you use a backer block, which you always should on work whose underside will show.

[Randy Benway]

Hi Andy,

I don't claim to be a good speller, that's for sure... but I'll compare woodworking resume's with you anytime.

My point was that Forstner bits and Multi-spur bits are used inter-changeably when they shouldn't be. You didn't say what actual type(s) of bit you're raving about. I'm glad they work for you.

My friend invented a new type of drill jig years ago. I would go to the woodworking shows/stores and help him demo. It was AMAZING to us how so many woodworkers struggle to bore good, on-size holes. Almost every time they were using their 1400 rpm cordless drill and a brad-point.... made us smile. He used a commercial sharpener on his twist drills and ran them with a 2500 rpm corded pistol drill. Slicker than corn-through-a-goose... especially the end grain. All this tooling existed in the 80's when I served my apprenticeship in the pattern shop... I'm just passing on a little of what I learned.

Floyd,

Don't take my word for it. Grab one of your nice 1/4" or 1/2" twist drills and put it in your drill press. Spin it at 2500 rpm or more, back up the bottom, and try it on any veneered stock you want.

Regards,
Randy

[Pete Staehling]

FWIW, I never use anything on top and always have gotten nice clean holes on the top with forstner bits. I do find that a backer piece and/or care is require to avoid blowout in the back on exit. It helps to have nice sharp bits.

Brad point bits are okay, but IME forstner bits work better.

Avoid spade bits for any woodworking. They are for rough work like drilling holes for romex in wall studs.

[Lee Schierer]

FWIW, I never use anything on top and always have gotten nice clean holes on the top with forstner bits. I do find that a backer piece and/or care is require to avoid blowout in the back on exit. It helps to have nice sharp bits.

Brad point bits are okay, but IME forstner bits work better.

Avoid spade bits for any woodworking. They are for rough work like drilling holes for romex in wall studs.

When I use a Forstner bit for a through hole, I set the drill press so the tip of the center point will just start to come through the wood I'm drilling. Once I reach this depth, I flip the piece over and align the bit center to the dimple on the wood and start the cut from the back side. This yields a tear out free hole on both sides of the piece. You also get a thin wooden coin the size of the hole you were boring.

[Pete Staehling]

When I use a Forstner bit for a through hole, I set the drill press so the tip of the center point will just start to come through the wood I'm drilling. Once I reach this depth, I flip the piece over and align the bit center to the dimple on the wood and start the cut from the back side. This yields a tear out free hole on both sides of the piece. You also get a thin wooden coin the size of the hole you were boring.
I sometimes do that as well. I will caution that care needs to be taken to keep the two sides perfectly aligned. I have at times found the two sides to want to slightly misalign despite using the tiny hole from the center point.

My point being that either way you go you need to be careful. One way with not blowing through the back too hard and the other with perfect alignment.

[John K Jordan]

Randy,

I appreciate you sharing your experience. Like others, I also didn't realize the distinction between Forstner and Multi-spur bits although I use both and did notice the difference. Your points on pressure are good - even the good Forstner bits I use don't cut well without a bit of pressure. My favorite bits for hogging out rough holes are carbide Forstner bits - they don't cut very cleanly but they sure are fast and don't dull easily. I use them most often to drill deep holes in woodturning blanks before hollowing. (BTW, I always direct a strong stream of compressed air into the hole as I drill - it clears the chips and keeps the bit cooler.)

Your "point" about brad-point drill bits in end grain is good too. I noticed that years ago when drilling into end grain on the wood lathe when I thought the brad points would be a good idea. Far better are the standard bits after first drilling a starting hole with a center bit or starter bit.

I see you're in McKean PA. We used to go through that area on the way from south of Pittsburgh (near Elizabeth) to Erie to visit relatives (had relatives in Butler and Newcastle too). But it's been a while - over 50 years ago!

I don't know if you noticed, but your first picture (Attachment 407225) referenced as a Forstner bit didn't display properly. I can fix the message if I had the photo.

JKJ


Hi Floyd,
I must disagree with just about everything you've been told. I'm a retired wood patternmaker. Drilling a hole on size, on location, with decent finish is critical. When fabricating wood patterns and core boxes, everything was drilled then pinned with precision ground steel pins. It was MANDATORY that you had tooling that bored accurate holes. We all had Forster bits as well.... they were INVENTED 100 years ago for pattern work.

I suspect the drill bit that others are advising you to use is actually a multi-spur bit. The name Forster bit and Multi-spur bit have somehow become interchangeable now-a-days. THEY'RE NOT! They are two different animals and they behave totally different. It seems every type of drill for wood is being marketed as a Forster bit. This is a true Forster bit:

407225

Note the sharpened but smooth rim and small center spur. The Forster doesn't require the center spur to be engaged in the wood to remain on-axis. Forster bits do ONE thing well: they HOG STOCK like nobody's business! Patternmakers would use a Forster bit to hog stock away before going to a wood mill or over-arm router to profile a shape. The old guys had 2 or 3 of them in their Gerstner... sets are worthless. They are the WORST at boring holes. The small center spur makes drilling on center very difficult. They require high tool pressure so can only be used in a drill press. That high tool pressure also means MASSIVE BLOWOUT when exiting a hole. That's not what they are designed for.
This is a multi-spur bit:

407226

Multi-spur bits typically have a larger center spur that make drilling to a center line reasonable. They require less tool pressure so can be used in a hand drill. They definitely require the center spur to remain engaged or they'll 'spit out' the work piece fairly quickly. They leave a reasonably good finish but will also cause blow-out... you need to drill from both sides and meet in the middle to avoid blowout.

You mentioned your application is boring 1/4" and 1/2" holes. In that size, you can't beat a standard 118 deg drill bit. I own many brad-point drills (even a full set of Cleveland brand from 1/8"-1"...frightenly expensive 35 years ago) they all bore slightly oversize, are difficult to sharpen, and leave an average finish. Brad points also REQUIRE that you bore from both sides to avoid blowout. Brad points don't like end grain either. Patternmakers all used standard 118 deg drill bits when it counted. They are easy to sharpen, require low tool pressure, loves end grain, and leaves a good finish. As stated before, just use a piece of scrap as a backup and you'll get good results. Hope this helps! Randy

[Pete Staehling]

On the forstner vs multi-spur issue... I have both and my multi spurs were sold as forstner bits. It looks to me as if maybe half the time they are labeled as either forstner bits or forstner multispur, so there is a distinction in the actual bits, but the naming convention is certainly muddled in the industry.

I agree with Randy on a lot of the differences between the two, but for the use the OP mentioned I usually reach for the regular forstner and find I get good results as long as I take care to avoid blow out on the back side. Btw, I do almost all drilling that uses either on the drill press so achieving sufficient pressure and using a backer board are easy.

[John TenEyck]

In the set of Forstner bits I bought years ago everything under about 1-1/2" diameter have a solid rim, all those larger have multi-spurs.

FWIW, I've used spade bits with edge spurs many times to cut tear out free holes.

John