Drill Press & 3″ forestner requirements?
Somertime
| Posted in Power Tools and Machinery on
I have to bore many 3″ holes about 2″ deep for an order of 50 clocks made simply of a block of 8/4 cherry to house the Quartz clock fixture.
I have a small 1/3hp, 5 speed Harbor Freight benchtop drill press. It’s not enough to bore that kind of hole. Or is it? The belt slips.
I need a few recommendations. I have a small garage shop, and a fairly small budget so I can’t house or pay for a drill press salvaged from a sea vessel. One can dream…
1. What kind of power specifications should I be looking for with this type of operation?
2. What type of 3″ forestner bit should I get? (Brand names, and suppliers)
Now if I had a huge budget, what’s the best?
Replies
You might try using hole saws and drop the speed down to lowest speed.
Work the revolving saw up and down to clear sawdust, BUT be sure to clamp the blank tight to the d p table!
Also, saw only halfway in and then finish sawing from the back.
If the hole is supposed to just house the clock's works, no need to sand. A sanding drum (of a smaller diameter,) will finish up if you prefer perfection. Steinmetz.
For that kind of a run, especially with forstner bits of that size, you want to run at a slow speed. I would strongly advise getting a 12-16 speed 1hp floor mount drill press. You can "get by" with a large heavy duty bench top one, but if you are buying a new one - you would be better served with a floor sized one.
If you are in an area with a Sears repair center, they also function as a scratch and dent outlet - might find one there cheap. I picked up a belt/disc sander that had a broken box with no damage to the unit - normal price was $129 - I paid $48 and they had 3 floor drill presses there at the time. (I was actually looking for their variable speed grinder at that time)
If you have a drill press I would get a new belt (or some belt dressing from a auto store).. Tighten that sucker up...
Make a fixture to hold your work well..
I use forestner bits alot (L'CHEEPOS')
They run HOT as hell and WILL burn your work if you are not carefull.
50 is a BIG order for a bit but I would run it a 'sort of' high speed
and make sure I raised the bit often to remove all chips.. Tape a vacuume up there... DO NOT crank down on it to hard.. Make sure you bit is cutting on BOTH cutters and not just one side.. SOME CHEEP BITS DO THAT...
Get a nice stool to sit on and a glass of Jack or Coolaid AND Hang in there...
OH! DO NOT touch that bit! IT WILL BE HOT like ya' won't believe!
If you make a fixture to hold your peices... so all go to the same place... Drill out what you can with what ever you have available.. Then use the forestner to clean up for the final cut..
You know.. Like a 2 3/4 hole and finish at 3 inches.. Good luck!
TRY ON SCRAP FIRST.. cherry IS EXPENSIVE!
Edited 8/8/2005 12:50 pm ET by Will George
"so I can't house or pay for a drill press salvaged from a sea vessel." Some of the replies seem to have missed this point. Since I'm in the same arena financially, I can identify! Were I approaching this task, I would look for these features:
Tips, some mentioned above. By all means, a slow speed. Cherry will want to burn, you'll need to keep that bit clean and cool. If your current DP happens to be one of the better HF specimens and meets the description in bullet one, get a link belt and see if that solves the slipping problem. If it doesn't help, no harm done, as you can use the belt on your new machine. Definitely make a hold-down arrangement; you don't want that stock moving at all! Something that enables you to just pop the blank in and drill, production-oriented.
I have the Delta 1/3HP model DP300, if you want I'll do a trial run with the biggest Forstner I have and see how it performs. Personally, I don't think you need lots and lots of power to do this chore, as you'll be drilling at low speed. What you need is a solid link (so to speak) between the motor and the bit.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Another proud member of the "I Rocked With ToolDoc Club" .... :>)
Several good suggestions .... however, most of these clock-works require a metric sized wood bit, available from the supplier of the works. A Forstner is one thing, and those oriental-made knock-offs are a long way off the mark .... likely not up to the short run you're planning. Good Luck,
John in Texas
Something you might try on a piece of scrap. Use a 3" OD hole saw, then use a 3" OD forestner bit to clean out the center. 1/3 HP aught to do it if running at the slowest speed and the belt is tight and belt dressing applied. I'm presuming here that the hole is not to go all the way through? If it is, then just use the 3" holesaw.
PlaneWood by Mike_in_Katy (maker of fine sawdust!)
PlaneWood
Unless you have a drill press with a slow speed pulley set that will let you get down to around a hundred RPM this can't be done. Even at a very low speed, an Asian 1/3 HP motor will probably have a great deal of trouble pushing that large a bit.
For what you are trying to do, a larger press with a low speed drive, around 100 to 200 RPM driven by a 3/4 to 1 HP motor is what you need. For that many holes, a carbide bit would have a much better life span, but a carbide bit will require more power to drive than the equivalent well sharpened steel bit.
If you can bore all the way through, a fly cutter, which can be fine tuned for the perfect diameter would be the best choice and require less power to drive, but they're dangerous to use if you aren't trained in their set up.
John W.
Edited 8/8/2005 4:14 pm ET by JohnW
As someone who has drilled a LOT of 2" holes 3 to 4 inches deep in walnut I use a lot of forstner bits.
My experience is the big bits will slip in an import chuck, I ended up replacing my Delta one with a genuine US made Jacobs Super Ball Bearing chuck, doesn't slip.
If you don't want to buy a bigger press, you could use a series of smaller Forstner bits to hog out the material a half inch at a time...very slow but eliminates the need for a new drill press.
Unless the bit is REALLY sharp, get a couple of stones and hone it so it is SHARP. The more sharp it is, the less power you will need to use it.
1/2 horse power motors are easy to find and fairly cheap if you take your time, you might try upgrading your little drill press but even going through the drills, working up to 2" you are going to go nuts.
Start watching the paper and Craigslist.com for a bigger drill press or think about farming out that one operation.
Michael et. al.,
I had trouble with the cheap chuck that came with my Delta floor model drill press. I bought a ball bearing import from MSC for about $50. I has worked OK so far, but I haven't tried anything as tough as a 3" hole with a Forstner bit. $50 is about 25% of the cost of the drill press....
Somertime,
Since you are concerned about the limitations of your drill press, Have you considered using a router? With a pattern, it's fairly quick and easy to make nice, clean, identical holes for all of your clocks.
Good luck,
-Jazzdogg-
"Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie
i agree with jazzdog. try a router with a template. even if the hole isn't exactly perfect just make sure it's a snug fit and the rim of the clock should cover the slightly out of round hole. if there's any way to do it, don't make the block cuts until the holes are done. you'll have more to clamp onto. just a thought.
jericho
Ditto. use a router and a pattern bit. much easier, even if you have a big bad drillpress.
Mikeplease excuse my spelling.
Yes! Eureka! A router! Brilliant idea! You got me out of the box! Thanks!I have a guide brushing kit ready to work for that job, and the holes are actually only 1.25" deep instead of 2", so it shouldn't be too bad.Although a stool, nice cigar, and a slow glass of scotch would have been a welcome way to spend all of that time at the drill press.
Edited 8/9/2005 12:56 pm ET by somertime
Another option I just thought of is to use a deep hole cutter ( my mind just blanked on the name - kind with a circular tube with a drill bit in the middle - kind that you use to drill out a lockset). Use a bimetal one, and when the drill bit starts coming out the bottom, flip the piece over and put bit in the exit hole and drill down - this will avoid tearout.1 - measure the board twice, 2 - cut it once, 3 - measure the space where it is supposed to go 4 - get a new board and go back to step 1
I also thought of pattern routing, but then I noticed the holes are 2" deep - hard to find a pattern bit that long, and I'm not sure I'd want to use it if I could find one.
My vote is for pre-drilling most of the waste with multiple holes using a 3/4" or 1" brad point, then finishing with the Forstner.
The brute-force, probably fastest, solution would be to rent, borrow or beg a big honking Milwaukee right angle drill, the kind plumbers use. It's not an elegant tool, but it's specifically designed for making big holes, fast, all day long. Be sure the workpiece is extremely securely clamped.
Edited 8/9/2005 5:04 pm ET by Kent
I would definitely add another vote for the router solution. I used a template with a router in a similar situation where I needed several flat bottomed 1 5/8" holes at an angle and was amazed at how clean the result was. Just use a pattern bit or a guide bushing and don't unclamp the work from the fixture until you've verified that all the waste is removed.
Joel
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