Building some hollowing tools

[Paul Ray Moore]

I am in the process of trying to build some hollowing tools. One is going to be an Oland tool and the other, if I can bend the bar, will be a swan neck cutter.
I've read many post on this and gotten some good directions from a few folks but I've got a couple of questions before I move forward.

1. I've drilled a 1/4" hole in the end of the bar for the Oland Tool and I have a 1/4" cutter from Harbor Freight. Do I round off the corners of the cutter or just pound it in? One thread showed what looked like pounding the square cutter in the round hole. I do plan to continue using the bar and just replacing the cutters so I'm concerned if I'll be able to remove the cutter if I pound it in.
2. I bought a metric tap and die set. I was going to use a 6mm -1.0 for the tap but I am unsure of what size hole to drill before I start tapping it. Also I saw someone using a metal cutting oil, do you have to use this or will something like 3 in 1/motor oil/chainsaw oil/etc work?
3. How far in the handle do you put the bar? I've got a forster bit that I've been able to go in around 4 or 4.5" but I don't know if that is far enough. The overall bar is 18" and the handle is around 18" also.

Tonight I start trying to bend the 5/8" bar. Wish me luck. I have a torch and a bottle of MAP gas from Home Depot. Just the hand held kind. I hope to heat it until it is red and then bend it with some wrenches. Do you think that will work or do I have to have a vice?
If that doesn't work then I'll got to a 1/2" bar and use the 5/8" bar for an articulated cutting tip tool.

Thanks for the help so far.
Paul Moore

[Dahl Troy Perry]

Drill size for a 6mm-1.0 tap is a number 9 drill or .196 you can use a 3/16 drill witch is .1875 just take it slow and back it out revert 1/2 turn and any oil will work even Lars or bacon. Grease.

[Rob Cunningham]

I would round off the corners of the tool bit and glue it in with some thick CA
The tap drill for an M6x1 is 5mm or .1968" ( # 9 drill ) Any of the oils you mentioned will work for tapping.
When I made my hollowing tools, I put the bar into the handle 3".
You can probably get the 5/8 stock hot enough to bend with mapp gas but it will take a while. Make sure it's nice and red and work quickly. A vice would give you more control when bending. You can also slip a piece of pipe over the hot bar to get some leverage when bending.

[Paul Douglass]

I used a set screw to hold the bit in, drill the hole just big enough to slip the bit in. That makes it easy to change bits or take one out to sharpen.

[Art Kelly]

I used a set screw to hold the bit in, drill the hole just big enough to slip the bit in. That makes it easy to change bits or take one out to sharpen.

Me, too. Plus, I grind a little flat on the end of the cutter that goes into the holder, and I have a piece of 1/2" x 2" x 2" aluminum with a hole on the 1/2" edge and set screw on the 2" face. I use this to hold the cutter when I sharpen. (No pix--away from home.) This also allows nice even motion when sharpening so the burr is uniform.

$0.02
Art

[Paul Douglass]

Art. that's a good idea. They get a little hot on the fingers when you hold them to sharpen them.

[Paul Ray Moore]

Well it took me about a week but I finally got two hollowing tools built. One is a straight shaft and the other is a bent. I started by buying some 5/8" cold roll steel from Tractor Supply, $13.07, 36" long so long enough to make two tools; then set screws, around $2 and HSS cutters from Harbor Freight, $5.41. I had one piece of copper so I didn't have to buy a ferrule for one of them. Now that would have been all I had in these if I had owned a tap and die set but since I didn't, off to Harbor Freight to buy one, $13.15. I don't have a lot of metal working tools. I have a drill press, grinder and hack saw. I don't own a vice so if I can build one with these limited tools anyone can.
I started by cutting the 5/8" bar in half, drilled down the shaft 1/4" and then drilled the pilot hole for the tap, broke the tap off in the bar, :mad:
so to Fastenal for a real tap. Tapped the hole. Now turned a handle out of some scrap black walnut. I wish it was a little longer but it works.
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Now to build the curved shaft. Got the torch out and realized I was out of MAP gas. So off to HD again, also needed some copper for the ferrule, $10.74 for both. Heated the bar for :20 min never changed color. Realized I couldn't do it with MAP gas. At our club meeting Saturday I showed the straight shaft and told them I was needing help to bend the other. I had 2 people volunteer to help me so off to their house in the afternoon and got it built.
The bent tool is grabby. I can mostly control the straight shaft but I am learning how to control the bent shaft.
Here is a picture of it and the tips of both of them.
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Now time to practice. I found some scrap wood and started in. I got it in pretty good shape.
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Then BOOM!!!!!!:eek:
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Well back to the lumber pile tomorrow to see if I can get one finished.
Thanks.

[Bill Bolen]

Looks like you had a nice even wall thickness!

[David E Keller]

Looks like you had a nice even wall thickness!

He beat me to it! I think it's a good idea to cut a couple in half anyway so that you can see how you're doing on wall thickness. Think of this episode as a time saver... You didn't have to spend the time cutting it in two.:D

[neil mackay]

1. I've drilled a 1/4" hole in the end of the bar for the Oland Tool and I have a 1/4" cutter from Harbor Freight. Do I round off the corners of the cutter or just pound it in? One thread showed what looked like pounding the square cutter in the round hole. I do plan to continue using the bar and just replacing the cutters so I'm concerned if I'll be able to remove the cutter if I pound it inNo increase the size to take the square HSS, measure across the corners for the drill bit dia




2. I bought a metric tap and die set. I was going to use a 6mm -1.0 for the tap but I am unsure of what size hole to drill before I start tapping it. Also I saw someone using a metal cutting oil, do you have to use this or will something like 3 in 1/motor oil/chainsaw oil/etc work?
drill 5mm for m6 thread, your oil will work not the best choice, so take it easy



3. How far in the handle do you put the bar? I've got a forster bit that I've been able to go in around 4 or 4.5" but I don't know if that is far enough. The overall bar is 18" and the handle is around 18" also.
I would fit the tang at least 3" for a bar this size, ideally 5" would be best



Tonight I start trying to bend the 5/8" bar. Wish me luck. I have a torch and a bottle of MAP gas from Home Depot. Just the hand held kind. I hope to heat it until it is red and then bend it with some wrenches. Do you think that will work or do I have to have a vice?
Bend it in a good vice with a piece of tube over the heated end for leverage. Red hot is the way to go


If that doesn't work then I'll got to a 1/2" bar and use the 5/8" bar for an articulated cutting tip tool.


1/2" is fine for small stuff and shallow hollowing. Long hollowing it will vibrate and or bend.

I have both as well as 3/4" bars. Consider drilling a hole at 45' if you have a hassle with the bending. This get you under the lip etc OK.
Dont go for bigger than 1/4" for under lip turning as the bigger HSS is prone to catching , small is good here.
But big open hollowing no worries I have a 1/2" HSS for this, 20" long by 1"dia. bit of a mother but does the job.


Thanks for the help so far.
Paul Moore[/QUOTE]

[Josh Bowman]

I agree with make the hole fit the square bits. Here's some cheap bits that work great.
2 sizes:
http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5312&PMPXNO=939775 (http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5312&PMPXNO=939775)

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5316&PMPXNO=939967 (http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=383-5316&PMPXNO=939967)