I was here few weeks back asking about why my forstner bit kept stopping which I tightened the belts and it made an improvement.
We had a spare nearly new detroit press at the back of the shed so I’ve now switched to that. I have a 58mm bit that I’ve been using before I use the 3” but now that seems to not want to work either. I’m now wondering if maybe it’s the brand I have and that they aren’t the best quality. It’s mahogany cookies I’m trying to cut holes in. Is there a better brand that will make this easier. I’m even happy to do 3-4 cuts to create the size I’m after if it will be quicker. As 1.5hours to do one hole an inch deep is just not practical 😂
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https://www.leevalley.com/en-ca/shop/tools/power-tool-accessories/drill-bits/102819-imperial-saw-tooth-bits?item=06J7148
So is saw tooth a good type to use. I feel the teeth are what’s pulling up my press.
Maybe it’s your press drill that is to small.
Would that matter if I used a smaller bit though. As even my smaller bit doesn’t seem to be cutting well. The moto is still going and belts spinning so I assumed it was just the bit getting stuck
I would tend to agree with GulfStar and Lee-Valley Veritas. I do not own a drill press, but I do use Forstner bits. They do well for softer wood and shallow holes. They will get dull under heavy use and can be sharpened with diamond pads. When I need to drill past 3/8" deep in dense wood, I'll start the hole with a Forstner bit (up to 3/8" or 1/4") then pull out a spade bit. The Forstner bit is easier to start a hole straight and the spade bit will follow what the Forstner started and cut quicker. Spade bits need to be sharpened periodically, too. I also drill small pilot holes the size of the point of the Forstner bit.
I’m making clocks. So I drill a hole straight through then the point of the forstner bit sits on that. I don’t know if a spade would cut clean enough for the back.
Maybe my press is not big enough.
Some days the 57mm cuts great and I’ll do 3 overlap holes and it’s fine. Then the next morning it’s stalling again.
Thankyou. I’ll have to try another brand
I have an old set of fostner bits from China dating 30 years + bought for less than the single bit I suggested and drilled through teak and hardwoods since then . When they stall, I use à file or a Diamond plate and hone the cutter. Mahogany is an easy wood to drill, there is something in your set-up that is not right.
Yes it definitely isn’t right. It shouldn’t be this hard. I have a feeling it’s either the power of my press or bad bits. I’ve got a diamond file and tried sharpening my bits also. It has cut well before. So there must be something I’m missing. Thanks for the tips. I might see if I can have a look at it with someone who knows a bit more about the set up of the press as I’m only a beginner just winging it.
What speed are you running at? Should be around 500 rpm. Change the belt to the slowest speed and try that. And def sharpen your bits. I’ve used the same set of crappy harbor freight bits for years, I just hone often.
I have it set on the slowest I think it’s 250-260 I tried to up it to 450 to see if it helped as I was using a saw tooth but it’s still stalling.
There must be something I’m missing here as I’m trying all these tips and some reason it just stalls.
Hmm interesting….I’m not even sure this is possible, but is the chuck itself spinning out?
Nah all that’s all good. I’ve come to the conclusion that I’ve eliminated everything except the possibility that I’m not sharpening them properly so I’m going to have them sharpened properly by someone and see how it goes
You can use forstner bits in stages - drill out the centre and that will help a bit. For alignment, it's better to use a guide block with the largest hole drilled in it as bigger bits are more prone to wander if there is no centre spur
Wait, the motor is turning the belt and pulleys are turning but the bit is not? Is the chuck turning but the bit is not? Or does everything stop and all that's happening is a motor buzz? Is the bit spinning but not cutting? If the bit stops but the chuck head is turning then either your not tightening the chuck properly or the gripping teeth on the chuck are worn. If the bit is not turning and the chuck is not turning but the pulleys are turning and the belt is definitely not slipping then the tapered fitting for the chuck head to the shaft is worn or the shaft or both..or the bit is jamming and the taper is slipping because your beyond the torque capacity of your machine. This is a good thing as it prevents you from damaging some other part of the press or fry a motor. It doesn't help you get your job done however.
I have found with fostner bits, particularly on deep holes ,that you have to constantly keep retracting the bit and clear the saw dust and clean the gunk off the teeth as well or they will jam or quit cutting . They're not like an auger that sends the waste away they just wallow in it. I was drilling a deep wide hole in a willow turning the other day and maybe because of the nature of the wood I had to drill for a few seconds, like maybe 5 seconds so maybe 1/4" at a time and clear the dust then drill again.
So update.
I had someone check the bit and definitely wasn’t blunt. We trialed a few things and found that it worked at a faster pace..
I tightened the belts/pullys, and now if it jams they stop also. But before they sounded like they were going still (I can’t open the lid when it’s on, it’s like a safely lock or something)
It’s set on 500rpm now. Before it was 250-260.
I’ll cut slow and give it breaks in the hope it doesn’t get hot and blunt.
This is the 57mm. The 3” still doesn’t want to work.
drill out a pattern of smaller holes inside the circle of the forstner to hog out waste in advance, it makes a big diff for the larger bits. Pilot drill the center to stay on track.
Hello Jessica98,
I grew really tired of trying to cut holes in hardwood with my existing Forstner bits. They were lower end bits from a long time ago. It was difficult enough drilling in softwood. When I retired a few years ago my colleagues gave me a generous gift certificate to one of my favourite tool stores so I treated myself to a set of high end Forstner bits. The cut speed and quality was far beyond any expectations I had. I am sure there are a number of brands and price points in the higher quality range but mine came from: https://www.fisch-tools.com/en/produkte/031bs-black-shark-forstnerbohrer. Now I can drill oak, maple, beech, walnut etc without an issue - and this is with a very small undersized drill press or my old Dewalt cordless drill.
Thank you! I have heard of this brand, I’ve also noticed a lot of demo videos in the us are using fisch.
Have you considered a template and router bit? I also make clocks (https://beasleysevindesigns.com/ ) and fight the larger Forstner bits. Now I have a template and use a pattern router bit. Works great. Ironically, I used a Forstner bit to make the pattern.
We really don't have enough information. Can you tell us the brand and model of both drill presses that you have used. In particular, the horse power of the motor. Photos would be helpful.
In the mean time, can you find someone with a big hulking drill press with loads of power and try using your forstner bit with it. This will tell you if the fault is with the bit or with your drill press.
You said that these bits used to work well. What has changed since then?
Also, I've got to ask, is there any chance that the drill press is running backwards.
Will your drill press work with regular drill bits and small forstner bits (ie, 1/4" or 3/8")?
If everything else is working properly it has to be dull. Even a crappy bit will cut well when sharp. It just becomes a matter of how long it stays sharp. Even a nice Fisch bit will stop cutting well if cooked. If you get the cutters too hot, a brand new bit will cut like crap. Same goes for every cutting edge in your shop. Excess heat build up often comes from not clearing enough material so the extra friction makes things bind and get hot.
I’d get a second opinion on the bit’s sharpness, or better yet, learn to check for sharpness yourself using your thumbnail. IMHO.
I have to say, I'm really confused as to what the actual problem is.
OP is trying to drill a 3" diameter hole into mahogany cookies (end-grain)
If I understand correctly.
I don't know if this is a through hole or not, but I would suggest a hole saw.
Trying to cut a 2" or 3" hole into end-grain with a forstener bit is not the easiest thing to do.
You could also mount the cookies on a lathe and turn the hole to size.
As another suggestion, you could try drilling multiple holes with a regular twist or brad point bit. The bigger the better. Then clean out with the Forstner bit. That should reduce the amount of wood the Forstner is trying to take on each rotation. Drilling through holes also goes pretty fast. For a 3" hole, your should be able to drill about eight 1/2" through holes.
I've struggled with forstner bits, but not this large of diameter. If they are cheap ones and you haven't sharpened them yourself, based on my experience they are absolutely dull - some of them come that way. Even when sharp, they also don't cut well if speed is too high and they don't cut well with too much pressure and they don't cut well if the chips/waste isn't cleared frequently....it seems like they can very easily get a chip "wedged" (for lack of better word) right at tip or along cutting edge that gums things up.....For my cheap/sale bits that I use for shop furniture/jigs and home projects, I find if I sharpen the bit, keep them and the chips very clean frequently in use, don't overheat them, and don't bear down too hard, i can get results the same as with the more expensive bits I have.
If the stock is not well supported on a sturdy drill press table, it will tilt slightly with the bit buried in the wood and a 3 inch bit would stop most drill presses.
I might be looking at this from another angle. When you want to cut mahogany, it’s hardwood and needs stronger bits. High-speed steel, a usual material to create bits, is good for light metals, PVC, fiberglass, and wood. But for hardwood like mahogany, black-oxide coated bits are better. So, check your bits.
I've never seen black-oxide coated Forstner bits.
Use a Fly cutter.
HM
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