35 replies so far
#1 posted 07-25-2011 04:29 AM |
You could chuck a router bit maybe. You could buy a cheap Forstner and grind the point off. -- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog |
#2 posted 07-25-2011 04:37 AM |
i have to go with bertha -- Ike, Big Daddies Woodshop, http://www.icombadaniels@yahoo.com |
#3 posted 07-25-2011 04:39 AM |
What size hole? I was thinking plunge router as well. -- We must guard our enthusiasm as we would our life - James Krenov |
#4 posted 07-25-2011 06:08 AM |
I don’t think that I would want to use a Forsner bit (or spade bit, hole saw, etc) without a center spur. That’s what keeps the thing from trying to skate all over the place when it’s turning. Just for giggles, try using a hole saw without the drill bit. -- Adversity doesn't build character...................it reveals it. |
#5 posted 07-25-2011 06:15 AM |
I’m pretty sure there aren’t any forstners made without the center spur. Start the hole with the “normal” Forstner, then grind the point off to finish it. -- If you're going to stir the pot, think BIG spoon or SMALL boat paddle. David Grimes, Georgia |
#6 posted 07-25-2011 08:01 AM |
That is what I would do; get it started, then take the point off. -- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence |
#7 posted 07-25-2011 08:05 AM |
Set up two bits? I guessing there is more than one hole to drill. -- We must guard our enthusiasm as we would our life - James Krenov |
#8 posted 07-25-2011 08:53 AM |
The spur has a function; there for a reason. |
#9 posted 07-25-2011 02:26 PM |
Use two bits the same size, one WITH the spur, one WITHOUT. Start your hole with the spur-bit to get the outer portion of the bit below the surface and then switch to the de-spurred bit to finish. You did not say how deep your intended hole is so this may or may not work for you. -- HorizontalMike -- "Woodpeckers understand..." |
#10 posted 07-25-2011 02:57 PM |
You’re looking for “rim-guided” forstner bits http://www.jamestowndistributors.com/userportal/show_product.do?pid=12353&familyName=Forstner+Bits -- The Wood Nerd -- http://www.thewoodnerd.com |
#11 posted 07-25-2011 02:59 PM |
Thanks Woodnerd, I’d never heard of those! -- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog |
#12 posted 07-25-2011 03:19 PM |
The Nerd dun good! Cool! Bookmarking the link as I type… -- HorizontalMike -- "Woodpeckers understand..." |
#13 posted 07-25-2011 03:39 PM |
I’ve a small set of forstner bits that I simply grinded the bit off. You don’t have to pre-drill it—just use a drill press and make sure your work item is clamped or otherwise secured down and it’ll be fine. Go slow for the first couple of rotations to make a groove, then crank it up fast and hold on tight. those flat-on-purpose bits look really cool! -- Lis - Michigan - http://www.missmooseart.com - https://www.etsy.com/people/lisbokt |
#14 posted 07-25-2011 06:08 PM |
That looks just like mine so I wondered what the big deal was?? Googling Forstner bits http://www.google.com/search?rlz=1T4ADRA_enUS423US423&q=Forstner+Bits&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1024&bih=515 -- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence |
#15 posted 07-25-2011 06:14 PM |
I bet the rim-guided are not best sellers at $45 a pop. How about start ALL the holes, then grind the spur to finish (and still need only one) ? OP says “a… hole…” so maybe he only needs to do one, anyway. -- If you're going to stir the pot, think BIG spoon or SMALL boat paddle. David Grimes, Georgia |
#16 posted 07-25-2011 06:29 PM |
Historically, all Forstner Bits were “rim-guided.” They had several advantages including flat-bottom holes, VERY accurate hole diameters, and are capable of drilling “partial” diameter holes since they are guided by the edge of the bit. In the last 20 years or so, machine spur “forstner” bits and other variations of bits got confused with the more traditional design. Techichally, only rim-guided” Forstner bits are truly Forstner Bits. Thank you Woodnerd for including the link to Jamestown Distributors that shows true Forstners. -- Chesapeake Bob, Southern Maryland |
#17 posted 07-25-2011 07:28 PM |
Thx bentlyj ;-) Good article, how does that feed point retract? -- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence |
#18 posted 07-25-2011 08:03 PM |
What ever it is, it has to be strong!! Those feed screw pints take a lot of torque. years ago I need to drill a 2” hole through about 8” of framing for a conduit. The purchasing agent bought the cheapest forstner bit he could find without a feed screw. By the time I got that hole drilled, it was the most expensive 2” hole in the world!! Gotta love the stupid decisions people who have never done any real work do to save a buck ;-)) -- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence |
#19 posted 07-26-2011 12:41 AM |
Topamax… your’s is good example of a good tool used for the wrong job. The correct bit would have been a bit such as is sold for plumbers or electricians, many times made by Milwaukee. The Forstner bit without the feed screw was not proper bit for this job,as you quickly discovered. -- Chesapeake Bob, Southern Maryland |
#20 posted 07-26-2011 04:16 AM |
Thanks everyone for your input! @TheWoodNerd: that’s EXACTLY what I was picturing in my head. Though about $60 cheaper :) I guess I’m going to take an existing bit and grind off the pilot. I thought of that, but didn’t really want to go that route. -- Aaron |
#21 posted 12-27-2012 02:50 AM |
Forstner bits without a center point are available from Carbide Processors Inc. at carbideprocessors.com The firm makes cutting diameters from 1/4’ to 3” |
#22 posted 12-27-2012 03:09 AM |
@marvinlee: Thank you! This looks even better than other options I found because it’s carbide. Unfortunately they are out of stock on the 2.25” size I want…and sizes in that range. But I’ll keep checking. Thank you! -- Aaron |
#23 posted 12-27-2012 03:31 AM |
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#24 posted 12-27-2012 05:03 AM |
I have a few sizes that I drilled through 3/4” oak that I keep on hand and use as templates. Then grind the pilots off and clamp the template onto your work piece and use as a guide. -- Jeff |
#25 posted 12-28-2012 03:03 AM |
I went a different way when I needed big holes part way through the stock with no center mark. I cut the size hole I needed in a piece of scrap with a holesaw, taped it to my workpiece, and used a pattern bit in my router. Made a very clean job of it! -- " I'll try to be nicer, if you'll try to be smarter" gfadvm |
#26 posted 12-28-2012 03:59 AM |
Gadvm, that sound like a winner. -- I'll be a woodworker when I grow up. HHHOPKS |
#27 posted 03-22-2015 03:40 PM |
waho6o9, it looks like the MaxiCut Forstner still has a center spur so the hole is not flat on the bottom (there is a big divot), right? |
#28 posted 03-22-2015 04:06 PM |
I’ve used center cutting end mills on wood before when trying to achieve a flat bottomed hole. The piece being drilled needs to be very well secured before beginning. |
#29 posted 03-22-2015 04:29 PM |
At 1”+, Andy’s (gfadvm) suggestion is the best. If it’s deep enough, you can use a plunge type pattern bit or a bowl bit, once you get deep enough to engage the bearing on the pattern. -- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton |
#30 posted 03-22-2015 04:42 PM |
Yes daviddoria there’s a divot in the middle. |
#31 posted 03-22-2015 05:23 PM |
If you grind the pilot off (I’m thinking of doing this with a 2” forstner bit), then how does it cut the center 1/8” or so of the hole? It seems like a “stub” will form (kind of the inverse of the divot formed by the pilot tip/brad point), not allowing the drill press to continue down into the workpiece. Can anyone comment on if this should be a concern? Thanks, David |
#32 posted 03-22-2015 08:02 PM |
That’s the reason I used a center cutting end mill, the cutters extend all the way to the center of the bit. If you were cutting a soft wood and only had 1/8” or so that wasn’t being cut, it’s likely it would be mashed out of the way. If the center spur was larger and you were cutting a harder wood, like oak or hickory the cylinder of wood not being cut would be much more difficult for the bit to mash out of the way. |
#33 posted 03-22-2015 09:09 PM |
Yea, that makes sense. It seems like we’re looking at over $100 for a 2” end mill though (versus $22 for a Porter Cable or equivalent forstner) :( |
#34 posted 03-23-2015 12:28 PM |
No doubt, a center cutting end mill of that size wouldn’t be cheap! |
#35 posted 01-08-2017 07:50 PM |
Late coming to this thread but it helped to solve the mystery form me. It looks like the best way to go is a forstner for most of the hole and finish it up by routing with a straight bit and template. Thanks. |
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