Vintage Drill Press as Hollow Chisel Mortiser????

[John Bradley]

Good afternoon folks!

Here is my query:

I am currently considering buying a vintage drill press in excellent/near mint condition that was likely designed for metal work. It is a Van Dorn (later Black and Decker), 1 hp/25 amp 220v motor with fixed RPM at 900.
I have the ability to make a hold down jig for stock to use as a hollow chisel mortiser.
What are your thoughts on this? Is 900 rpm enough spindle speed for that usage? ( I see that most of the modern machines are 1725).

I cannot see paying $$$$$! for a Powermatic made in Taiwan that does not even have the capacity to mortise timbers like I will be using (old barn beams, etc.)

Would appreciate any input!

John

[Erik Manchester]

John, you will be fine with a 900 rpm motor as most of the problems with hollow chisel mortises is that they are not sharp enough, insufficient clearance or turning much too fast. The high speed and lack of clearance often results in overheating.

The longer the stroke, the better the drill will work for mortise cutting.

[John Bradley]

Thank you, Erik!!!!

[Doug Dawson]

I am currently considering buying a vintage drill press in excellent/near mint condition that was likely designed for metal work. It is a Van Dorn (later Black and Decker), 1 hp/25 amp 220v motor with fixed RPM at 900.
I have the ability to make a hold down jig for stock to use as a hollow chisel mortiser.
What are your thoughts on this? Is 900 rpm enough spindle speed for that usage? ( I see that most of the modern machines are 1725).

I cannot see paying $$$$$! for a Powermatic made in Taiwan that does not even have the capacity to mortise timbers like I will be using (old barn beams, etc.)

Part of the issue with using a drill press as a hollow chisel mortiser is that the chisels have to be "driven" into the corners outside the drill bit inside the chisel. That's why the "lever arm" with a dedicated hollow chisel mortiser is so long. With a drill press, all you have is a wheel with a couple of spokes poking out of it. Are those spokes on your vintage machine even as long as the lever arm on a cheap import hollow chisel mortiser? It's not about the drilling, even a portable drill could do that.

I got rid of my drill press decades ago, partly because it turns out that in woodworking a machine like that is (almost) always second best to some other tool that can do the job better, or else the drill press can't even do the job at all, competently.

You mention mortising timbers? You will not be using a drill press as a hollow chisel mortiser for timber-framing type stuff, or at least not for very long.

A drill press can drill holes, at least somewhat straightly. I can do that with a drill just as accurately (I've been doing this for a long time, and that includes a lot of machine work where it really matters; muscle memory and hand/eye coordination counts for a lot.)

[John Bradley]

Part of the issue with using a drill press as a hollow chisel mortiser is that the chisels have to be "driven" into the corners outside the drill bit inside the chisel. That's why the "lever arm" with a dedicated hollow chisel mortiser is so long. With a drill press, all you have is a wheel with a couple of spokes poking out of it. Are those spokes on your vintage machine even as long as the lever arm on a cheap import hollow chisel mortiser? It's not about the drilling, even a portable drill could do that.

I got rid of my drill press decades ago, partly because it turns out that in woodworking a machine like that is (almost) always second best to some other tool that can do the job better, or else the drill press can't even do the job at all, competently.

You mention mortising timbers? You will not be using a drill press as a hollow chisel mortiser for timber-framing type stuff, or at least not for very long.

A drill press can drill holes, at least somewhat straightly. I can do that with a drill just as accurately (I've been doing this for a long time, and that includes a lot of machine work where it really matters; muscle memory and hand/eye coordination counts for a lot.)

Thanks for the comments!


The lever arm on a Van Dorn Press is a single arm actuator and approximately 18-20 inches in length, hence, good leverage for chiseling. That was my thought exactly to your point.
You mention a drill press can drill holes "somewhat straightly". If that is the case, the drill press is not properly adjusted, or has run out. Properly tuned, a quality press can drill deadly accurate holes all of the time. Relying on only hand/eye coordination in jointmaking will ultimately lead to errors that will multiply along the process line of construction. I love doing hand work, but have you ever mortised a white oak beam that is 8 or 10 inches deep by hand?
My interest in using the press is to rough out the majority of the waste. It can be done with a properly powered machine, razor sharp chisels and flipping the stock halfway. After 31 years as a framer, I have carpal tunnel in both hands and multiple degenerated discs in my neck.
Time to start doing things the easier way!

[Doug Dawson]

The lever arm on a Van Dorn Press is a single arm actuator and approximately 18-20 inches in length, hence, good leverage for chiseling. That was my thought exactly to your point.
You mention a drill press can drill holes "somewhat straightly". If that is the case, the drill press is not properly adjusted, or has run out. Properly tuned, a quality press can drill deadly accurate holes all of the time. Relying on only hand/eye coordination in jointmaking will ultimately lead to errors that will multiply along the process line of construction. I love doing hand work, but have you ever mortised a white oak beam that is 8 or 10 inches deep by hand?
My interest in using the press is to rough out the majority of the waste. It can be done with a properly powered machine, razor sharp chisels and flipping the stock halfway. After 31 years as a framer, I have carpal tunnel in both hands and multiple degenerated discs in my neck.
Time to start doing things the easier way!

A typical drill press will have a runout at the quill in the 1 to 2 thou range. Mine (a 16.5" Delta floor stander) was about 1 thou or so. Pretty good, as these things go. But "deadly accurate" quite not. I don't miss it.

Re the multiplying effects of errors in drilling, you'd have to come up with some really pathological examples of how this would have an effect in cabinetmaking, or certainly timber framing, and how a drill press would help you mitigate that, if you were good with drill alignment. The art of accuracy in woodworking is not in everything being hyper-accurate, but in recognizing where accuracy is important, and where it is not so critical.

I've cut timber-frame grade mortises by hand, in large hunks of wood, (with a mortising chisel no less) but I've never needed a drill press to do so, and I'm not even sure how it would be practical to mount a gigantic such timber as you describe, on the press table. It would be easier to use a portable drill. I'm not suggesting you use an eggbeater here, BTW.

A drill press, a moby one as you describe, would be a fine and imposing conversation piece for the shop, but for mortising, IMO no.

[Bradley Gray]

I have an old drill press that I use for hollow chisel mortising. It works fine for 1/4 -1/2" chisels. I have another drill press for drilling so I usually don't have to fool with uninstalling the mortise attachment - unless I need 2 drill setups.

I also have a portable chain mortiser that I use for big work- for timbers it is much easier to move the mortiser.

[John Bradley]

A typical drill press will have a runout at the quill in the 1 to 2 thou range. Mine (a 16.5" Delta floor stander) was about 1 thou or so. Pretty good, as these things go. But "deadly accurate" quite not. I don't miss it.

Re the multiplying effects of errors in drilling, you'd have to come up with some really pathological examples of how this would have an effect in cabinetmaking, or certainly timber framing, and how a drill press would help you mitigate that, if you were good with drill alignment. The art of accuracy in woodworking is not in everything being hyper-accurate, but in recognizing where accuracy is important, and where it is not so critical.

I've cut timber-frame grade mortises by hand, in large hunks of wood, (with a mortising chisel no less) but I've never needed a drill press to do so, and I'm not even sure how it would be practical to mount a gigantic such timber as you describe, on the press table. It would be easier to use a portable drill. I'm not suggesting you use an eggbeater here, BTW.

A drill press, a moby one as you describe, would be a fine and imposing conversation piece for the shop, but for mortising, IMO no.

I greatly appreciate the insights!

At 1-2 thou runout, that would be more than accurate in my book for most woodworking and timber framing. "Deadly", not quite, I agree, but wood is a natural material that even when properly dried (air NOT kiln!), moves constantly. I have never seen that level of accuracy with a hand technique in drilling in over 30 years of production carpentry.

Here is a good example of a "pathological" hand drilling fault that cost the GC plenty of $$ in the end:

We were doing a timber frame for a custom house here in PA. The GC hired some local Amish carpenters who were purported to be experienced framers. I was watching these guys carefully, as this was their first gig with our crew. They were drilling peg holes through tendons for draw boring which creates great strength in timber framing. Hand drilled with bit/brace. Their exit holes were 1/2 inch off in most cases; guess they had not figured out how to keep the bit square to the tenon! By the time I caught the error, about a dozen beams had been prepped.......wrongly!. Waste of time and material. It is one thing to toss an SPF stud, but you do not toss a single beam that cost a half day's wages very easily.
Our crew was using a porta mate with electric drill and the peg holes were spot on.
Point is, yes, you have to know when to be accurate. This was a case where it mattered. In a production arena, time is money; machines win in this game. Yes, I love to do hand work, but save it for hobby.
I am sure there are skilled hand workers out there, but even they would bankrupt a job like this one.

[Erik Manchester]

Timber framers are using chain chisel mortise machines to rough out the mortises and finish with a chisel, a drill press is fine for small mortises in a hobby shop, but anyone making a living with their tools is likely using something else like a chain chisel or swing chisel mortise machine as time is money.

[Rick Potter]

Have you looked into finding a chain mortiser, as Bradley mentioned. Wouldn't that be the right tool for timbers?

[Bradley Gray]

The mortiser I have is a Hitachi. It will cut a 1 1/2 x 5 x 7" deep mortise without moving the base. Very little clean up with a chisel

[Doug Dawson]

We were doing a timber frame for a custom house here in PA. The GC hired some local Amish carpenters who were purported to be experienced framers. I was watching these guys carefully, as this was their first gig with our crew. They were drilling peg holes through tendons for draw boring which creates great strength in timber framing. Hand drilled with bit/brace. Their exit holes were 1/2 inch off in most cases; guess they had not figured out how to keep the bit square to the tenon! By the time I caught the error, about a dozen beams had been prepped.......wrongly!. Waste of time and material. It is one thing to toss an SPF stud, but you do not toss a single beam that cost a half day's wages very easily.

They were just playing with you, English. ;^) Either that or you thought you were hiring the Amish, but what you got was Irish Travelers.

I noted that you'd have to have some decent skill for working straight, which an experienced hand tool worker has. (Analogously, if I asked you to draw a circle by hand, you'd probably come up with something that looked like a child's drawing of a sun, but a skilled artist could draw something that was actually round.) I tend to reach for a hand tool before I'll turn on the machine, but like you I too am getting old.

Re accuracy in drilling, I've been doing car repair and restoration for most of my life as an avocation, and many a time have had to drill (and thread) holes in engines or transmission housings etc., and I do it by hand with a power drill, and it always works out well. Some hand/eye coordination and mechanical sensitivity is helpful.

[Bill Dufour]

How about a powerfeed drill press?

[Bill Dufour]

We were doing a timber frame for a custom house here in PA. The GC hired some local Amish carpenters who were purported to be experienced framers. I was watching these guys carefully, as this was their first gig with our crew. They were drilling peg holes through tendons for draw boring which creates great strength in timber framing. Hand drilled with bit/brace. Their exit holes were 1/2 inch off in most cases; guess they had not figured out how to keep the bit square to the tenon! By the time I caught the error, about a dozen beams had been prepped.......wrongly!. Waste of time and material. It is one thing to toss an SPF stud, but you do not toss a single beam that cost a half day's wages very easily.
Why did the exit holes matter? had this been explained to the workers? IS there some advantage to angled holes like drawing the beams together.
Bil lD.

[John Bradley]

We were doing a timber frame for a custom house here in PA. The GC hired some local Amish carpenters who were purported to be experienced framers. I was watching these guys carefully, as this was their first gig with our crew. They were drilling peg holes through tendons for draw boring which creates great strength in timber framing. Hand drilled with bit/brace. Their exit holes were 1/2 inch off in most cases; guess they had not figured out how to keep the bit square to the tenon! By the time I caught the error, about a dozen beams had been prepped.......wrongly!. Waste of time and material. It is one thing to toss an SPF stud, but you do not toss a single beam that cost a half day's wages very easily.
Why did the exit holes matter? had this been explained to the workers? IS there some advantage to angled holes like drawing the beams together.
Bil lD.

Yes. The holes are actually not angled at all, just drill fractionally inward toward the cheek of the tenon, so that when the peg is driven, it mechanically pulls the mating piece (the piece with the mortise) inward super tight. All the holes are marked via CAD.
Sorry to have gotten off on a tangent.

Originally, I was just interested in coming up with an idea for drilling mortises in a hobby shop with a mechanism that would be able to occasionally handle a larger beam than a Delta or Powermatic could handle. I have access to chain mortisers, so will likely use that, as they are super in their purpose.