Drill press underpowered or ???
forestgirl
| Posted in Power Tools and Machinery on
Got my super-duper Colt MaxiCut 1-5/8″ Forstner, dedicated to drilling tough end grain for a couple of projects. It cuts slick, as long as the drill press keeps going, but it doesn’t, LOL. Cheap little Delta benchtop, has served well for most things.
I looked under the hood, and the belts aren’t slipping, the whole thing just stops, so I just keep plunging — plunge, release, plunge, release, plunge, release. Eventually, I get the 3/4″ hole that’s needed, no burning, chips eject willingly.
So, is this simply a horsepower thing?
forestgirl — you can take the girl out of the forest, but you can’t take the forest out of the girl 😉
Replies
hello forestgirl to ancer you yes it is underpowered and you need to wach doing what you have been doing you can do more harm than good doing that you dont want to push any thing to work harded than it is meant too.
How many horses has the cheap little Delta got? If it is a 1/2 or even 3/4horse then that is not a lot for a forstner type bit of that diameter, so I would expect to have to run it at a slower speed for more torque..Fat forstners like that need lots of grunt, and the type of wood also has a bearing .
Edited 12/9/2009 4:25 am by philip
Hey, Philip. If was a little warmer than 20*C outside, I'd run out and check the HP, but suffice it to say, it ain't much, LOL. I took the belt down to the slowest setting, but ya know what? I had to change it for another drilling task, and I just wonder if I might have forgotten to change it back! I'll double-check.
The first hole I did in the end-grain of Ash was done with a bit from an inexpensive Forstner set. That was nearly hopeless. Got the Colt and at least it was doable. I'm making some glue-blocks like the one below, need to go to a somewhat softer wood methinks:View Image forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
The rule of thumb I've heard is the larger the dia of a bit the slower the speed.
Does your drillpress have different pulleys?
Will Rogers
I did a personal test about a year ago with Forstners FG. I chose both a 1/2" and 1 1/2" to test. The test was run in both a piece of poplar and a piece of oak. I drilled a hole in each at every speed my DP has which ranges from 250 rpm to around 2000 I believe. Interesting results I either posted on another forum showing the boards marked with the DP speed in each.
The best speed I found for the 1 1/2" was around the 600-700 rpm range using a firm plunge and release as soon as the bit started to slow. I think it is important to release to clear the large chips produced by a Forstner. The best results for the 1/2" came around 900 rpm give or take using the same plunge and release but the release was not necessary as quickly as with the larger bit.
Just grab some scrap and find your speed as the type of material used in the Forstner could be a slight variance in the results I suppose as I only used the cheap set of Forstners I have which actually give excellent results.
Hope that might help and have a good day...
Sarge..
Woodworkers' Guild of Georgia
Thanks, Sarge, interesting stuff that. With all this $$ going out for turning "supplies" (wow, those scroll chucks are expensive!), I don't see a new DP in my future, so will have to either get the Delta to do it, or change woods. Ash was simply the only thing I had at the time that was thick enough for the purpose.
Sheesh, just remembered, a friend loaned me a Jacob's Chuck until mine gets here. I can use my lathe to drill the big hole!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I didn't catch the "end grain" drilling the first time FG. I personally don't think the HP is a factor as a DP is a finesse machine with the tip and bit doing the dirty work. HP could affect a larger bit but I think the fact you are drilling in end grain and the fact you are using ash is the culprit. I have worked with a lot of hickory.. ash.. pecan (which is technically hickory) and I can tell you that whatever you use it better be sharp to start with as the wood will dull it pretty quickly.
Keep in mind not so much with small runs but I sometimes do in excess of several thousand bd. ft. prepping it for others and it's very hard. I have a 1/2 HP motor on my Ridgid 15" DP and have not found anything yet that it won't handle due to the lower HP. Proper bits sharp.. rpm correctly chosen and technique is far more of a factor in drilling an accurate hole than HP IMO.
Just the opinion of one that has a 1/2 HP DP and uses it often to drill with Forstners....
Good luck with that expensive new thingy they call turning....
Sarge..
Woodworkers' Guild of Georgia
Edited 12/9/2009 12:31 pm ET by SARGEgrinder47
"HP could affect a larger bit ..." I was thinking 1-5/8" is kinda, sorta large. No?? Anyway, today I brought home another be-all-end-all Forstner bit, the Bormax(?). Have a lonnnnnnnnnnnnng hole to drill in stock for a peppermill. Will be able to compare that one with the MaxiCut, though the stock and the diameter aren't the same. The design of the bits are both quite different from standard bits, but also different from each other.
I'm having fun with the spinny stuff. When I finish a few of these wine stoppers, I'll post pics.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
FG, that is a large diameter for a small drill pressespecially with that type of cutter. In addition, the type of forstner bit you showed is the kind that requires extra torque-look at the leading edges of the peripheral cutters.
If you had a saw tooth type it cuts in a different way.
But on slowest speed , steady feed, good condition bit , withdrawing/preventing clogging, you should be able to do a few holes if you aren't in a hurry.
Philip Marcou
1 5/8" is sorta large but.. only 1/8" larger than the 1 1/2" I used on both poplar and oak in my test. I sucessfully drilled with every speed on my DP which has 12 but.... it required different technique when I got up to the high speed which was a challenge. Again.. I got the best results with a 1 1/2" FB at around the 650 rpm range. Lower than 500 got poorer results but still substantial results... above 900 rpm got very poor results with the 1 1/2" but I techniqued my way through up to almost 3000 rpm. The results just got poorer the higher I went up from the 900-1000 rpm mark.
Regards...Sarge..
Woodworkers' Guild of Georgia
But, shouldn't the bottom inch, or so, of the interior be tapered, so as to guide the poor little doomed pepper corns into the waiting ravenous jaws of the chompy part? ;-)
The Delta bench top drill press is great for small jobs; I use one. I believe the larger floor model drill presses such as Powermatic have chucks with a larger diameter shaft that holds them to the press. The larger shaft has more hold area-necessary for the more powerful motors. I often drill large longer holes on my lathe with no problem. I cut into burls with a 2 1/8 diameter Bad Dog Biter bit-like a Fosner with carbide.
It's partially horsepower, but it's probably more about the bit you're using. Forstner bits have full diameter contact while they're cutting and that can cause a lot of resistance.
If you can adjust your belt configuration to slow the drill press down, that should help. Other possibilities are the species of wood you're drilling (soft woods are more difficult), and the sharpness of your bit.
Yep use the slowest speed for the most "grunt" and just enough feed to keep the bit cutting (not just rubbing). Faster speeds . . . well you get the cut done faster but takes larger motor.
Come to think of it you may be just feeding the bit a little too fast.
Check sharpness of the bit. You know me. Sharp is never sharp enough.
I have had some bits of this type not have enough clearance angle and they get hot fast even though the edge seams sharp. Re sharpen with diamond hone (maybe a file) to give more clearance on the bottom side of the cutting edge behind the edge.
I dab the hot bit with a touch of candle wax if going deep or in the resinous purple heart. Not because of the clearance problem just in general.
Prevents that squealing to. Might be detrimental to your gluing.
As a last resort you could make a few stabs with a much smaller bit then go with the final bit.
roc
Give me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
Edited 12/9/2009 4:34 pm by roc <!-- ROC2013 -->
Edited 12/9/2009 4:36 pm by roc
>they get hot fast even though the edge seams sharp<The point being they rub rather than cut well and so takes more power when forcing the bit down into the fibers enough to cut at all with the feed handles.So a bit that may normaly cut fine with your size DP may not cut and will jamb if not enough clearance angle to get the edge down into the wood even though the edge feels sharp.rocGive me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )
If the motor stops when you plunge the bit, it is certainly the motor. From my feeble mind, I don't see too much harm from repeatedly plunging unless you don't leave enough time to let the heat escape from the motor. I see it as a possibility for the motor to overheat and be damaged using this process.
It would seem advantageous for you to use the lathe if possible. You would have to rig up something to support the work piece. In my case the drill press (1 HP) has a larger motor than the lathe (3/4 HP) so using the lathe wouldn't help. Best of luck in your venture.
I would perform some quick checks on your drill pressure to make sure it does not need some maintance. Unplug DP. Remove all drive belts. Tug on each pulley to make sure they are not slipping. Most pulleys have steel set screws holding aluminum pulley to a steel motor shaft, they will always work themselves loose. Snug down pulley set screw. Check nut holding quill shaft pulley to make sure it is tight. Check to make sure bit chuck is not slipping on the quill shaft. Basically hold chuck in one hand and turn quill pulley, should be tight. Drilling speed should between 500-900 rpm. Slooooooly engage bit to wood. There should be no need to jam bit into wood. I regularly drill 1-1/2 inch holes into Gabon ebony (damp) with a 1/2 hp DP. Remember your bit slices the wood and needs time to be ejected from the bit. 1/2 hp motor is plenty to drive a 1-5/8" Forstner bit, I use a 3/4 hp to drill 2-1/2-3" chinese forstner bits with no problem, low and slow.
Thanks, everybody, for the additional info/ideas. I missed a few posts in the last week or so. I did discover that I hadn't re-set the belts from when I needed a higher speed, so that may have been part of the problem.
I have received the chuck that fits my lathe, so I may just go to that when I need to do these end-grain holes.
here is a speed selection chart for drill presses with various types of bits and materials
http://images.meredith.com/wood/pdf/drill-press-speed-chart.pdf
it may help your problem- underpower is not likely the issue
Hey,
It's not a horsepower problem. I say that because I recently drilled ash end grain with 2 styles of 2" Forstner bits for a client. Knowing beforehand Ash is a mother to drill, I tried different horses but ran face-first into burning and chattering. Imho, the nature of Ash end grain is to frustrate the heartiest of bits and patience of the operator.
Don't feel alone & Good luck,
Mikaol
Zombies..........
Braaaaaaaiinsss...mmmmmmm
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