Heads up on cheap generic drill press (DP)

Posted by on August 26, 2013

Not much of an article

Just a heads up for anyone about to buy a cheap / generic drill press (from Harbor Freight or similar) – Make absolutely sure you test it right out of the box at the store, do not take it home without doing so.

Here’s the reason why, they often lack QC or ship out defective units from China on purpose (as for instance the buyer may be requesting a cheaper version) — The primary problem you’ll encounter is massive play on the quill, due to an oversized hole on the body. I don’t know how they manage to do this while they bore them out, but I’ve encountered 2 out of 3 drill presses had this problem. We’re talking over 5MM play with the quill fully extended, using a 3MM drill bit and measuring at the end of drill bit itself.

This short video depicts quill play and vibration (there was so much vibration one of my tools fell to the ground)

 

Do not confuse a factory defect vs a lack of adjustment on the quill (most drill presses will have a set / grub screw with a lock nut that is used to prevent the quill from turning, it also applies a bit of force that further reduces play, but it’s not a gib). If it turns or feels sloppy on that particular axis, it could be the setscrew is loose. The problem with the faulty bodies will present at near the full extension of the quill, there you’ll be able to push it around to feel for slop.

The spindles are fairly straight, I’ve measured 0.08mm on the worst one and the current one I own has a bit under that, which is expected on a non precision machine and it’s actually plenty good for most uses. However the quill has about half a millimeter of play, this is the best unit I could get from what they had in stock (plus returning them takes time and money, so you gotta draw the line somewhere).

In my particular case I’ve found the spindle to be supported on multiple bearings and not a single bushing, which is in my opinion quite good despite the low quality of the bearings, at least they’re there.
 

Put it on vibrate!

The second issue is vibration, and this one is hard to isolate specially if you are at the store or you don’t have the right tools at home.

I don’t think you can fully remove vibration from these drill presses, there are inherit design flaws that cause resonances everywhere and the 50/60Hz motor doesn’t help with this either. The actual belt tensioner is the primary culprit, it will transmit every single vibration the motor encounters, down to the body of the drill press and onto every other component, traveling down the shaft and onto the base, which then propagates to your work table, etc, etc.

However, there are a few things we can do, one is to check that both pulleys are not only running true, but are also level in respect to each other. Then, we can inspect the belt — it will usually be a low grade belt, possibly stretched and deformed from all the time it spent tensioned in one position ever since it left the factory in China. I don’t know why they don’t just put the belt in a bag and tell you to install it (this would help a lot of people familiarize with the pulley system). I think we can blame lazy people for this one or the factory for shipping them out with tension.

Not to forget, the motor is mounted on 3 or 4 places (more often 3 than 4…) make sure the motor is perfectly vertical to thus obtain a perfectly horizontal drive pulley. The issue with the tensioning system they use is that it pivots on a sloppy make-shift hinge with over-sized holes and it’s usually all bent up from mishandling during shipping, etc. You have to double check everything.

If you hear a sort of “click, click, click” coming from the drill press it could be the spindle pulley that happens to be loose, make sure both pulleys are tight on the shafts and that they’re sitting on the slotted end. If it sounds along the lines of “clank, clank, clank” then it’s probably the belt rubbing against the housing.

For an old drill press, any sort of clicking noise could well indicate worn out bearings, specially if you subjected them to side loads.

 

To recap…

Don’t expect much from a cheap drill press, if you can, buy an old used one. The older, the better. Even if it’s a monster and you need 4 people to move it around, you’ll be investing in a tool that will far outlive you, vs a piece of Chinese crap that will make you waste your time and money. Not to say there aren’t “gems” within the “turds” but, make sure you double check everything before you commit to one of these lousy imports.

Don’t rely on brand names either, most of them are importing from China, sure some pay the extra for QC and are usually better in that regard, but you can still expect faulty motors and whatnot from your favorite brand names… So, bust out your tools and spend some time before you fully setup your new drill press.

Have fun.