Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => AmpTools/Tech Tips => Topic started by: spacelabstudio on January 30, 2012, 03:10:46 pm
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After having borrowed a friend's drill press this afternoon to drill out a few chassis and make a few turretboards for a group DIY project, I've come to appreciate just how useful a drill press can be. I can scarcely imagine having accomplished what we did in the amount of time we did with small hand drills.
So, probably, at some point, I'd like to buy a drill press. I'm afraid I'm too ignorant to shop for one. Anybody have any specific recommendations? What should I be looking out for when shopping for a drill press? What's the difference between the $150 model and $600 model?
Thanks!
Chris
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Even some of the "cheap" imports are pretty good.
for amp work,try to find one with a 1/2" chuck, the 5/8" chucks wont hold the small bits need for driling holes for #6 and #4 screws.
Runout (how much the drill bit wobbles)
That's what plagues most imports, It always has seemed to me that the excess runout is caused by cheap chucks. good chucks are expensive and can cost as much as a cheap drill press to cure that.
16" is a great size
Variable speeds are a must, the more speeds the better.
IF I ha had the chance to do it all over, I would have sprung for a "better" press from Grizzly or the Porter Cable that lowes sells.
Do look into a "robo sander" . it is a drum sanding acsessory for drill presses that will let you do some neat things with wood if you're so inclined. I think stew mac offers them, but could probaly be had cheaper else where.
Just a couple thoughts
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My little bench top drill press has served me well for over 12 years. I used it for every turret board and chassis I've done plus hundreds of other home projects.
(http://home.comcast.net/~seluckey/amps/warbler/w_05.jpg)
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I bought a very cheap (49€) drill press that was on sale in a local hardware store. It's obviously Chinese. I was a bit reluctant at first but it turned out to be pretty good and has served me well so far. The only drawback is that the table is not as sturdy as it looks. So when you apply pressure while drilling it bends down slightly and the holes are not exactly vertical. I solved this problem with pieces of wood that I jam under the table. However, this only occurs with thick and hard material. It is not an issue for "normal" drilling.
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Drill presses are blessed by being easy to make half-decent models. They are large enough, and the spindles can be made large enough, that the bearings can be made big. Big bearings are a lot easier to make than small bearings. Also, all the force on a drill press is on one axis, and the bearings see very minimal lateral force, so they are only really dealing with the centripetal force from the spinning, and on most bits that isn't a very big deal. What that means is that you can usually get by pretty well with a fairly inexpensive drill press. A more expensive drill press will be better, but the diminishing rate of returns happens a lot lower on a drill press than, say, a table saw.
The main limiting factor, then, is how big you need it to be. I've got a couple of really huge drill presses, because one of the main things we use them for is a fly-wheel cutter for soundholes and soundhole rosettes, which is a lot more demanding than using twist bits or even a step bit. Get a drill press that can handle the width of a chassis in both axis, so ideally at least a 10" swing, and a table that will let you stand a chassis up on it's front or back. You can probably get away with an 8" swing, but some holes will be less convenient, as you'll have to be turning your chassis around front to back a lot.
THIS (http://www.grizzly.com/products/5-Speed-Baby-Drill-Press/G7942) would probably be adequate, and the price seems right. Something a bit bigger would be nice, but spend more if you get something bigger (there is a lower limit to the cost of decent bearings!) If you're doing metal work, I would avoid radial drill presses (though for woodworking, mine is fantastic!)
Never try to make it work as a mill or a overarm router. The chuck simply can't handle the lateral force, and it is very easy for the chuck to just fall out. Which really sucks.
Gabriel
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Good thread. I too am yearning for a drill press and am lost by too many choices and lack of ability to evaluate. $109 seems a good place to start.
I was using an old Craftsman contraption that holds an electric hand drill. But the mechanism had too much play and I broke it while trying to improve it. :icon_biggrin: Hell, my hand has less play than that thing!
Anyway, I just won a Dremel 210 drill press on eBay. It's the old-fashioned model where the Dremel rotary tool is held steady by 2 clamps on the upright pole; the table moves up & down with a screw adjustment. This seems to get better reviews than the newer Dremel drill presses and "Workstation" which are said to have way too much wobble. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150739740103 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150739740103) We'll see. It looks like it comes with a separate router base, and both need a good cleaning.
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THIS (http://www.grizzly.com/products/5-Speed-Baby-Drill-Press/G7942) would probably be adequate, and the price seems right. Something a bit bigger would be nice, but spend more if you get something bigger (there is a lower limit to the cost of decent bearings!)
I have ordered a LOT of tools from Grizzly.
I've found their power tools to be among the best coming out of China. Most of it comes out of Taiwan, which has been a mainstay of manufacturing for decades.
I've literally bought THOUSANDS of dollars of their equipment and only had minor complaints if any. Shipping's a cold bitch on the big stuff to say the least. but they do have 3 warehouses and with some luck you may live close enough to one.
OH! forget those laser thingys they put on those! The beams are too wide to get you closer than a 1/16th of an inch DON"T let those gimmicks be a selling point!
Now that you have a nice drill press, you'll also want a nice center-punch too! and again, with the nice drill press that drill nice holes, to accurately position those holes, get a digital or dial caliper too.
drilling a nice round hole, perpendicular to the work is only half as important as putting it just the right spot.
Ray
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Even a $50 (what they cost last time I bot one) Chinese drill press is massively better than hand drilling. And by the way, if the chuck is too big, you just go buy a smaller chuck with a threaded stem, put your teeny bits in the little chuck it, and tighten down on the stem of the intermediate sized chuck with the big chuck. Done.
I believe it is darn near impossible to drill a row of 3/8" holes for your controls across the front of a chassis *convincingly* straight w/a hand drill. On the other hand, if you clamp a piece of wood to the table and move the chassis along you can make near perfectly centered and perfectly spaced holes very easily. The problem with hand drills making lots of holes that are supposed to be the same size and linear with each other is that you get done, see that you screwed it up, and then you don't feel like doing "perfect" work any more for the rest of the project. That blows. It's a cruddy feeling, IMHO. And you just did it on the chassis, probably the first thing you cut when you are building an amp. So, right from the beginning you have this piece of pollution. I hate when that happens. Nobody will see if you get your 12AX7's a little out of line. Volume-treble-bass controls? Anyone can see if they are misaligned.
The other thing a drill press is useful for is for tapping. Put the tap in the chuck and turn the tap by hand (you do not apply power!) and the tap will be nicely plumb with the surface. This makes a huge difference, both in how nice your threads are, and how long your taps last before they snap. If you try to make a 6-32 tapped hole and wiggle the tap when threading, you'll be lucky if the threads don't strip out under any decent amount of torque. Especially in soft aluminum.
A Chinese one will work fine, those little Delta ones are very nice. I *believe* you will find the little benchtop Deltas are also made in China......depending on just how old they are.
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i own the model shown in the link below. it allows for the use of fence with the T slots in the table. might be more than you want to spend, but it's an excellent value and has plenty of work space, even with the power switch being the weak link - richard and i replaced mine with a 20A toggle.
http://www.toolbarn.com/delta-17-950l.html (http://www.toolbarn.com/delta-17-950l.html)
+1 on a grizzly - just try to get a table with T slots. from what i've seen, the stuff that's mfg'd. in taiwan is of better quality than the stuff being mfg'd. on the mainland.
the drill press is the MOST used power tool in my shop for amp building, other than the CNC machine.
i custom made the fence out of 2"x1" aluminum bar stock, a couple of pieces of 5/16" coarse all-thread rod, a pair of square nuts (for the T slots), and a pair of wing nuts. how did i drill the bar stock? i used a pair of C clamps and another section of bar stock to make a temporary fence just to make sure the holes were in as near perfect alignment as possible along the long axis of the fence. dial calipers and/or a good machinists rule, punches, and a scribe are a must as well.
we used the "laser" guide all of about a dozen times - the battery died and still is.
--DL
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There are two tricks to getting good Asian built power tools, both of which depend on the company who is importing it. First of all, part of what you spec when you send them your designs (or when you chose from their catalog of designs) is how tight the tolerances will be. It is a lot more work to make a +/- 0.001" part than a +/- 0.01" part, and that is reflected in the cost. Second, the company you are buying from should have their own QC guy at the factory. If a company relies on the factory's own QC people, you will not get what you ordered - they are paid by the factory, after all. Grizzly, Delta - those sort of companies have their own QC people at their Asian factories, and it is reflected in the quality of the tools they sell. But again, it is more expensive, which means the tools are more expensive. And of course, rejects from the higher end customers get re-branded for the bargain basement brands. Just because two tools were made in the same factory, to the same basic design, does not mean they are the same - not by a long shot!
I've actually got three drill presses, two USA made Delta's here in the shop, and a dinky little Asian made Craftsman at home. The Delta's are fantastic, but the Craftsman is perfectly adequate form most tasks that I use it for. Kind of small, but I do most of my aluminum work on that tool, and it's chuck with hold wire gauge bits down to 80, which is pretty impressive in a 3/8" chuck! And, it is easy enough to move around that I can use it at my electronics bench if I want to have heat while making a circuit board, or something else with easily cleaned up waste (but don't EVER try to drill aluminum in a room with carpeting!)
Gabriel
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Drill press is a blessing. :worthy1:
I bought a Wolfcraft universal drill press stand (tool suggested by a customer of Doug) 2 weeks ago, & it's just awesome.
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Thanks for the advice, y'all. I feel much better informed!
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I picked up a used Rockwell 3/8" varible Speed drill at a Flea Market several years ago for 20 bucks. It's nice having my turrets standing up straight and square now instead of like the Leaning tower of Pizza. Don't use it very much but when I do need it, it's just what the doctor ordered. Platefire
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I bought the $100 bench top bargain press about 10 years ago. It has saved the day so many times. Still works great. I bet I've spent more money on bits than I have on the press.