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Brian Kent
06-23-2015, 10:57 AM
Using a Whiteside 1414 Round-nose router bit in a drill chuck on a lathe. Tell me why it is a dumb idea.

The 1414 is a 1-1/4 diameter round nose bit. I am wondering if this could help me form the bottom of the cup of a small chalice.
Another alternative would be the 1376B Bowl and Tray Bit, also 1-1/4 " across.

I have made about 50 of the small chalices, 1-3/4" inches wide by about 7" long. The cup is about 2-1/2" deep. I use a 1-1/4" forstner to begin the hole, but small tools like scrapers chatter on the bottom and my boring bar is too clumsy for that size (and my skills). So most of the chalices have a ring on the bottom from the forstner.

Or I could get a dedicated hollowing tool, at which point wise people tell me to save for a hollowing system, which I will. But I don't have that money at the moment.

Please tell me why this is an idiotic, broken, no good idea.

Brian Brown
06-23-2015, 11:41 AM
Never tried it, but I would think if you get bad chatter with a scraper, you would get much worse chatter with the set up you described. How about something like this to reduce scrapper chatter? I know this listing is for the sleeve, but they have just the rest too. I just couldn't find it by searching for tool rest.

dubdubdub.pennstateind.com/store/CLTXX1.html#OrderByItem

I am sure you can get one like it elsewhere also. PSI also sells this tool, but I have never heard of anybody using it, or their thoughts.

dubdubdub.pennstateind.com/store/LRBIT1.html

It is what you are describing, with no motor. I think this would be one of the tools that ends up in the unused Tool pile. I cringe when I see the tools in my unused pile!

Klaus Waldeck
06-23-2015, 11:53 AM
I believe that router bits work best at high speeds. At least that is what I am learning. I used to run my bits on my router at the slowest speed, but now I run them at the highest and the cuts are better. So, I doubt the drill will spin the router bit fast enough to give a clean cut. Neat idea though! I suspect you wanted to chuck it in the drill because in a router the base is too large and the bit too short to reach the inside bottom of the cup?

Kyle Iwamoto
06-23-2015, 11:55 AM
End grain? Try a Termite tool? Works real good on end grain. Trouble is, it don't work on anything else. And it don't work on the sides. BUT thinking of what you're describing, a Termite MAY be the answer. OR a Hunter/round carbide tool rolled way on its side, which essentially what the Termite is.
OR you can wait till the Symposium and pick up Lyles hollower for cheap........ :)

Oh, as long as you advance the bit real slow, it MAY work, but I think it's a bad idea. Router bits are designed to cut at 10K RPM and up. Depending on the size. A big one like that maybe less.

Bruce Pratt
06-23-2015, 11:56 AM
At those dimensions and distance off the tool rest, you should be able to use a half round/curved scraper (not a round nose) e.g. Sorby 828H. Try a slight negative rake (handle high), and a slight rotation of the handle to lift the far edge of the scraper off the tool rest. Alternatively, try a Hunter #3.

Brian Kent
06-23-2015, 12:00 PM
Thank you Brian.
My thought was to mount the router bit in the tail stock so it would be stationary while the piece spins around it. I just turned a small chalice, using the point of a small scraper, and it chowdered up the end (kiln dried birch). I think it would have gone better using a steady rest.

So I am trying to limit vibration in the piece I'm turning as well as the tool. But I guess that is always the challenge. Spin a piece of wood around at hundreds of rpm's, stick a sharp tool against the free end and command everything not to vibrate.

Brian

Dennis Ford
06-23-2015, 12:05 PM
I think chatter is going to be a problem. For that size you do not need a hollowing system, just a hand held straight cutter. Consider mounting a High Speed steel cutter tip in the end of 1/2" round bar and putting a handle on it. A small piece of 3/16" like this: http://www.mcmaster.com/#8813a28/=xr0fnr ($3.93) super glued into a drilled hole will work fine (shape it before gluing).

Dwight Rutherford
06-23-2015, 12:19 PM
I agree with Dennis, for chalices there is no need for a hollowing rig. Hand held as described will work fine.

David Delo
06-23-2015, 12:35 PM
my 2 cents for someone who has never used a router bit on the lathe.

1.) The profile of the 1414 might lend itself okay for a safe successful cut but I doubt you would like the cut quality. I think you would introduce a sanding problem you wouldn't like.

2.) As stated by others, router bits are meant for higher rpm's than a lathe will spin.

3.) If you decide to try it, I wouldn't hold than bit in a 3 jaws drill bit holder. I'd use a collet chuck with a reverse adapter in the tail-stock.

4.) Your 2.5" depth is not that deep. You should be able to get good finish with 1/2 round scraper or Hunter type tool or even a easy wood round cutter. See if you can turn your tool rest into the hole a little bit for a little additional tool support.

Reed Gray
06-23-2015, 12:42 PM
I guess it depends on what can end up working best for you. Considering that you will be reaching out off the tool rest 3 or more inches, you need 1/2 inch bar stock to keep chatter to a minimum. Considering that the piece is also sticking out a ways off the headstock, chatter and vibration from the wood will also pose problems. Round off the cylinder, mark your low spot on the chalice cup, then hollow before turning away more of the outside. Having a cardboard or plywood template to stick inside the cup part will help. When doing finish cuts on the inside, scraper at a 45 degree angle, or a hook tool. You can use square stock, and cut a 45 on the cutter end for a carbide tip, which isn't too difficult to do. A flat scraping cut can work, but the shear angle works better. A negative rake scraper will do a good job, but again, you need 3/8 or so thick to avoid tool chatter. You may be able to get away with using a 3/4 wide by 1/4 thick swept back negative rake scraper. They exert almost no pressure on the wood when cutting and are for clean up work only. I have seen hook tools too where you take 1/2 inch drill rod, cut down the center for an inch or so, shape, heat, and bend, then temper. I have one, but don't really know how to use it. My only metal skills are grinding....

robo hippy

Brian Kent
06-23-2015, 1:34 PM
I just tried the tray router bit. Nope. Not at all. Chatter.
Then I tried the steady rest and it helped a lot.

For the record, I use a roughing gouge on the outside until I have a cylinder shape. Next is the cup hollowing. I use a forstner bit to remove most of the material. Then I use the lightest possible touch with a half round scraper, 3/4" x 1/4". On the flare at the rim I use the point of a freshly sharpened v-shaped scraper , backing off when it shakes.

What I just now tried was the steady rest after the stem was already formed, so I have hopes that it will work even better when it is still a solid cylinder.

Thom Sturgill
06-23-2015, 1:53 PM
When I turn goblets, I turn the outside to about the point that they start to curve in and sand nearly to finish. My sides generally close in slightly at the lip. I mount the steady rest before hollowing and hand hollow with mostly Ellsworth hollowers followed with a inside bowl scraper.

After hollowing and sanding inside and out, I finish the stem and base.

Stan Smith
06-23-2015, 2:31 PM
I believe that router bits work best at high speeds. At least that is what I am learning. I used to run my bits on my router at the slowest speed, but now I run them at the highest and the cuts are better. So, I doubt the drill will spin the router bit fast enough to give a clean cut. Neat idea though! I suspect you wanted to chuck it in the drill because in a router the base is too large and the bit too short to reach the inside bottom of the cup?

i think that routers run at around 22,000 rpms.

Stan Smith
06-23-2015, 2:33 PM
When I turn goblets, I turn the outside to about the point that they start to curve in and sand nearly to finish. My sides generally close in slightly at the lip. I mount the steady rest before hollowing and hand hollow with mostly Ellsworth hollowers followed with a inside bowl scraper.

After hollowing and sanding inside and out, I finish the stem and base.

I learned your method the hard way, but it works for me.

Geoff Whaling
06-23-2015, 3:38 PM
Turning into end grain is always problematic & each species of timber has its quirks. I break the rules and turn end grain goblets and vase forms as I would turn a conventional face plate grain orientation bowl. I know its turning against the grain. Neil Scobie taught me to break the rules IF it works, in other words experiment to find the tool & technique that works. I use air dried and kiln dried timber in my linear laminated goblets which means chatter & vibration are always an issue due to the end grain and the glue up itself.

I turn to a cylinder between centers; form an accurate well made tenon; true up the face; turn the lip/rim of the goblet only (not the sides); turn & finish the inside; then turn & finish the outside of the goblet cup with no tail stock support; fit a jamb chuck/mandrel to the goblet cup & reintroduce tail stock support; turn the stem, finish & part off.

Tools I find very handy are a Sorby 828H 3/4" curved scraper reground as a negative rake scraper (i.e. as a very curved skew profile) & the Robert Sorby RS213 Large Tear Drop Cutter on a straight round shaft tool. The 826H is also good but I don't own one. I also use the 8004H etc if items are large enough. My go to scraper for goblets is the Sorby RS213 Large Tear Drop Cutter as the round shaft allows me to experiment with shear angle to optomize the cut/scrape.

http://www.auction2015.woodturner.org/Diamond-Lil-by-Geoff-Whaling_i22309955 is a two piece goblet but the turning technique used is the same as above.

Shawn Pachlhofer
06-23-2015, 4:25 PM
if someone else hasn't mentioned it - if it's like any router bits I have - you'll have 2 large cutting surfaces contacting the wood at the same time.

maybe grind one of them off?

Ron Rutter
06-23-2015, 5:10 PM
if someone else hasn't mentioned it - if it's like any router bits I have - you'll have 2 large cutting surfaces contacting the wood at the same time.

maybe grind one of them off?

Shawn. Doing that would create unbalanced forces & vibration on the bit & also the wood as well, as those bits don't have small surfaces. Not good! Ron.

Shawn Pachlhofer
06-23-2015, 6:47 PM
holding a router bit steady and rotating wood around it - you're basically using the bit as a scraper.

imagine you took a round-nose scraper and stuck the entire cutting surface into the wood. Not good.

now double that by having 2 cutting surfaces in the wood at the same time - double not good.

Leo Van Der Loo
06-23-2015, 11:30 PM
Brian I haven’t read every post here totally, so I maybe saying the same thing others have said already.

To get a nice finish in endgrain isn’t easy with scrapers, and as you have found vibration is a problem, lots of that is from the clearance in the bearings, needed to be able to turn and worse if the bearings are close together, not much you can do about that.
What does help is using a cutting tool rather than a scraper, and I have used the Termite made by Oneway, it will cut both green and dry wood, there is very little chance of catches if you use the tool as recommended.

Here is a link that shows how the tool cuts and how to hold it, also another link to a tool review about the Termite tool, it should help you make a decision if this is a good tool for you, I would think that it is 316167

https://www.youtube.com/watch?v=jtMDAmQyBU0

http://www.newwoodworker.com/reviews/termitervu.html

Brian Brown
06-24-2015, 12:58 AM
I have a termite tool, and it works well in end grain. Not so good in side grain. It leaves a rough surface, and clogs easily. Also, end grain takes the edge off somewhat quickly, and sharpening is not the easiest thing to do.

Leo Van Der Loo
06-24-2015, 1:11 AM
I have a termite tool, and it works well in end grain. Not so good in side grain. It leaves a rough surface, and clogs easily. Also, end grain takes the edge off somewhat quickly, and sharpening is not the easiest thing to do.

You are right about it not being a sidegrain turning tool Brian, there are certainly much better tools for that.

It is strictly a endgrain turning tool in my opinion and what I used it for, it does a reasonable good job on the inside grain like in turning a goblet and hauling the tool up the inside.

As for sharpening,I picked up a used router and leave it set up with the grinding point in it, any time I want to use the termite I clamp the router in the bench vice,and then the sharpening is quite quick and easy.

Richard Wolgemuth
06-24-2015, 9:16 AM
Here is a video of a guy doing exactly (if I understand correctly) what you are trying to do. He is making acorn boxes and not goblets, but he demonstrates that a router bit can be used: https://www.youtube.com/watch?v=D9CtwaY4hxA
It is a long video and the router bit portion is about 18:50 into it. Hope it helps.

Mark Greenbaum
06-24-2015, 9:49 AM
I usually start my hollowing with a Forstner bit, then scrape the inside corners and bottom to get the interior where I like it.

David Delo
06-24-2015, 10:33 AM
Here is a video of a guy doing exactly (if I understand correctly) what you are trying to do. He is making acorn boxes and not goblets, but he demonstrates that a router bit can be used: https://www.youtube.com/watch?v=D9CtwaY4hxA
It is a long video and the router bit portion is about 18:50 into it. Hope it helps.

Well, learn something new everyday.

Brian Kent
06-24-2015, 2:57 PM
Hey, thank you Richard.

Jeffrey J Smith
06-24-2015, 3:43 PM
Brian - when I learned to hollow from Dave Schweitzer, he showed me how he uses a cheap spade bit to drill the central hole. Grind off the central point of the bit, then grind the bottom of the bit to whatever profile you wish on the bottom - gently rounded works well. Remember to sharpen each wing separately - so they cut in the same direction - and you can drill all the way to the bottom of the vessel. When you hollow, there's no nub to worry about.

Seems like this would work for your chalices. You may still have the issue of trying to scrape end grain (it is a scraping cut) but it's cheap to try. Spade bits are pretty inexpensive.

Marvin Hasenak
06-24-2015, 10:41 PM
I use a modified round nose scraper, I increase the rake on it, to about 50 degrees. That works for me.

Tom Sherman
06-28-2015, 10:48 PM
Brian, I realize I am late to this thread, but you might try this website, http://woodennicol.com. Jeff has a drill bit he has sharpened like a bowl gouge that eats up end grain easily. Check it out.