I've had the Atlas drill press for a while now. It's a great machine, but even on the slowest setting it's too fast to drill a hole bigger than 1/4" through steel. (and even that starts smoking pretty good) I've seen a few ways to slow them down and all seem to work, but here's my own take on the idea. Didn't stop to take pics but when I started earlier this evening it was actually a pile of raw materials. Tubing. bearings, shaft and pulley. So not hard to make and went together quickly. Materials list should be evident when you see the pics. So I'm essentially two split collars and a couple of belts away from proper drilling speed for larger holes. The new attachment swivels around the tower to tension the front belt and the standard motor slide bit will tension the rear belt. Should be slowed enough for bigger holes but I have room to dial it in with different pulleys. Setting up a smaller Craftsman drill next to the Atlas to handle pilot hole duty. Also, check out the. Duplicator engine paint at your favorite parts store. The stuff goes on smooth and dries super fast. (this piece is Ford red)
That's a great idea! Almost every drill press is too fast for anything bigger than a 1/2" bit. I built a drill press than I can slow down to 60 rpm, and it has self feed.
Great idea ... my only thought is "will the motor have enough torque to drill at the much-slower-than-designed-for speed?"
I would think so, he isn't changing the motor speed, just the spindle speed by using different pulleys. A good rule of thumb for mild steel is 500 rpm for Ø.500 hole size, faster for smaller, slower for larger. We drill about 100,000 holes a year. You would be amazed at how many holes you can get with a drill bit, when using the correct chip load and cutting fluids.
Answer: Yes. A jackshaft/pulley system is a tried and true method for slowing these machines down. Just showing my take on it is all. There is a Popular Mechanics article with a rig using a 12" pulley pushing a 3" holesaw on this same drill.
that will make drilling easier. have you ever thought about getting a milling machine? the only thing you have to waste by going slower is time. but your cutting tools will thank you.
I guess my thought process was off a bit . After reading the replies to my comment, I agree that you guys are correct ... the drill press should have more torque AND run at a slower speed. I was thinking along the lines of an electric hand drill stalling on a burr when the speed is low and not having the torque to overcome the burrr ... slowing the drill down even more will not overcome the burrr, but that is obviously (obvious to me NOW anyhow) that would not be the case here. In the case of the drill press, you are not changing the overall speed of the motor itself like you are when you slow down a hand drill. I guess it is similar to a person riding a ten speed up a steep hill ... easier to climb the hill in 1st than 3rd ... power output (same person riding the bike) remains the same, just a lot easier when geared lower. Thanks for the correction .
this is awesome! ive been brainstorming ideas to add a 3rd set of pulleys to my pos delta press since i got the damn thing. thanks kevin.
Yeah, that accessory is pretty hard to find and can be expensive when you do. I considered making something similar, but the design I came up with made more sense to me given the available materials.
That is one thing I hate about 'variable speed' hand drills. It really means 'variable power' because you adjust it to a slow speed to drill a big hole, and it goes slow simply because you remove the power to go fast, thus it becomes weak as a kitten and stalls out at the first burr or tight spot. Pull the trigger to go harder, and it slips in the hole and suddenly spins up to a zillion rpm. If I ever buy another mains-powered hand drill it'll be one with a two speed gearbox. That is what you need.
Another alternative is a DC motor with a solid state controller. No torque loss at low speed and variable speed 0 to max motor speed with the turn of a knob. No mods to the drill press either. The red link belts shown in someone's pic are a very good investment for a drill press. Not too much advantage at low speeds but a definet advantage at high spindle speeds. They don't flutter and consequently don't cause spindle vibration.
Hey Deadelvis. What can you take a pic of what the spindle cover on yours looks like? Yours is the only one I've seen that still has it.
I looked at the DC motor conversion. I like the idea, but it seemed like a bigger h***le trying to find the donor treadmill to harvest parts then finding a way to mount the motor, possibly adapting the pulley, etc. So other than tracking down the parts it seems like a wash as far as the work involved. And my drill is no more modified than it would be with the DC motor swap.
I installed a Variac in my shop (variable ac transformer.) I use it mostly on my lathe for the same reasons you mentioned with your drill press. One unit is usually enough for the whole shop if tools are not too far apart. I see them for sale at fleamarkets and even car swap meets. $15 to $25 is normal. You wouldnt want to p*** one up for even a bit more. A very useful ***esory . If folks arent familiar with them I can make a foto. Don
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