In the first post of this series, I chronicled my experiences purchasing, transporting, and assembling Delta’s DP350 bench top drill press. You might want to go back and read it if you haven’t already. In this post I’ll look at the specifications and features of the drill press.
One of the first dimensions to look at when buying a drill press is what is the widest piece of stock the machine can drill into the center of. For some reason, manufacturers use this measurement rather than the more practical distance from the column (or back of the machine) to the center of the chuck. It makes the machine sound twice as big as it really is. So a drill press like the DP350, which claims to be a 12″ drill press, actually measures 6″ from column to center of the chuck.
Another critical factor in choosing a drill press is how deep a hole can you drill with it (quill stroke). Usually the longer the quill stroke the better. Delta claims the DP 350 has a quill stroke of 3-1/4″, but for the life of me I couldn’t get a stroke of any more than about 3-1/8″ no matter how I measured it. Then I figured it out. They installed a 1/8″ thick rubber ring on the quill, presumably to prevent the depth stop from banging into the head if you let go of the handles. This rubber ring prevents the quill from fully retracting, so if you need that extra 1/8″ of stroke you’ll need to remove it.
Speaking of quill travel, the DP350’s quill lock seems a bit anemic. It has a plastic handle and feels sloppy, like you’re going to strip the threads every time you lock it down. It hasn’t failed to hold the quill in place for me yet, but it doesn’t have the solid feel it probably should.
The DP350 spindle has a Jacobs 33 taper. Delta supplies a vanilla 1/2″ three-jaw chuck that uses a chuck key. The provided key has one of those annoying springs that you have to compress to use the key so you don’t accidentally leave it in the chuck and turn the drill press on. The Jacobs 33 taper is pretty common, so you can always upgrade to a better chuck later.
The depth stop is attached to the quill rather than located on the quill handle. This type of stop is usually more accurate and easier to set. It features a quick adjust nut, so rather than wasting time screwing and unscrewing the stop, you can press the release on the stop nut and slide it into position. You can still spin it up and down like a real nut for fine adjustment. Out of the box, my depth stop was loose on the quill so I fixed it by tightening the bolt that holds it on the quill. Also, the stop nut wasn’t squarely hitting the angle bracket they use for a stop. I think a little shim will fix that nicely.
The built-in lamp is a nice add-on. It can be turned off and on independently of the drill press and can be positioned just about anywhere on the left side and front of the press. At first I had a problem getting it to stay where I put it — the flexible arm seemed loose and the lamp would sag no matter what position I tried. To fix the problem I ended up straightening out the lamp and turning the head counter-clockwise one rotation; this seemed to tighten the flexible arm a bit. After that it stayed exactly where I put it.
To get a better look at the variable-speed mechanism, I pulled the top cover off the drill press by removing the 6 screws. Six rubber pads isolate the cover from the rest of the drill, presumably to reduce any vibrational noise. With the cover off you can see the two variable diameter pulleys. When I replaced the cover, I had trouble threading the screws back in the holes. I then noticed the four corner bolts have machine threads and the middle two have tapping threads.
The 1/3″ HP 120V motor attached to Delta’s variable speed mechanism will drive the chuck from 500 to 3,100 rpm. Interestingly, they only label the most extreme speeds on the speed control dial: 500 RPM and 3,100 RPM. Some Amazon customers have taken measures into their own hands [What’s This?], but doing so accurately will require some sort of tachometer or stroboscope. As I have not built, bought, or borrowed a way to measure the speed yet, I’ll leave that for a later post.
At 9-1/2″ wide by 9-7/8″ deep, the table actually is a little bit wider than Delta’s stated 8-1/2″: an extra inch for free! The table doesn’t have a flat bottom; rather it has tapered supports, which makes it much harder to clamp things to it. You can crank the table up to 1-1/2″ below the chuck to about 13″, depending on exactly how far the chuck’s jaws are extended. The only way I can think of that Delta got the 14-1/4″ chuck to table capacity is if they measure to the taper. From chuck to base measures 18″. Again Delta gives you 19″ in their specs.
I loosened the table locking bolt with a 3/4″ hex socket — I should have used a 19mm socket, but I didn’t have one handy. Then I removed the table alignment pin to test how far I could tilt the table. Delta claims you can turn the table from 90° left to 90° right, but in actuality the table spins 360° around the table locking bolt. The scale riveted to the base of the table only reads from 45° left to 45° right. There is a hard-to-see witness mark on the table that you’re supposed to line up with the scale, but given that a) the witness mark is 1/2″ above the scale, and b) unless you spin the table around the column to one side or the other the chuck gets in the direct line of site, I don’t see the scale being very useful.
Finally, let’s get a feel for how big the machine actually is. If you read the specs on the Delta website and look at the drill press you might get a little confused. They seem to confuse the terms height and depth. Naturally you’d think height would refer to how tall the machine stands and depth would be related to how much space you need to clear out in back of the machine to get it to fit on the bench. Delta seems to have these two reversed. Anyway, the press stands 37″ tall and measures 22″ front to back. The machine measures more or less 11″ wide, depending on whether you take the pinion shaft handles into consideration.
All in all, my criticisms are minor. I’m frankly amazed Delta can produce a tool like the DP350 so cheaply, even if it is made overseas. If the drill press would have had the Festool name and the accompanying $600+ price tag, I would have expected everything to work perfectly right out of the box.
If I missed some features you’re interested in, let me know in the comments and I’ll either add them to the last part of the series or respond directly to the comment. The last part (for now) in this series will be my impressions after using the drill press for a while.
Price Update: Recently I received a Rockler flyer in the mail. They’re selling the DP350 for $200 until August 27th, 2010. Rockler’s current online price is $220, whereas Amazon currently lists it as $270. So much for getting better deals online.
Shopmaster DP350 [Delta]
DP350 Explosion [Dewalt ServiceNet]
Shopmaster DP350 [Rockler]
Via Amazon [What’s This?]














