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Help me decide which Oneway banjo

Joined
May 30, 2022
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Location
Belchertown, MA
Hi

I’m ready to pull the trigger on upgrading my 3520c with a Oneway banjo. The stock 3520 banjo is 5 3/4” tall. The 20” Oneway banjo is 7 1/2” tall, while the 16” banjo is 5 1/2” tall.

I’m guessing that Oneway uses a taller banjo because it’s more rigid. This sounds good, but the downside is it limits which tool rests will fit. My 14” power matic tool rest is too tall. My robust tool rests would work, but not the large inside rest I was thinking of buying from robust. I would need to replace my 14” rest with the oneway version and get the Oneway inside bowl rest.

The 16” Oneway banjo would not work with “regular post” robust rests, but works with the “long post” rests. From this I assume that the Robust banjo is taller than the 3520 but shorter than the 20” Oneway.

So I think it basically comes down to 20” banjo is probably more rigid, but won’t work with some tool rests.

What would you do?
 
What would you do?

I’d call ONEWAY. They are easy to talk with. The sell tons of after market banjos and will guide you through the choices

I believe the ONEWAY banjo is the best out there.
I also assume you are looking a the J rest from Robust- I love mine and use it on any bow large than 14”
And smaller ones on occasion.
 
If you want to use specific tall tool rests go for the 16". If you haven't had a problem with the rigidity of your Powermatic banjo at only 1/4" taller the 16" should be fine.

I really like the Oneway banjos. What don't you like about the Powermatic?
 
Three things I don’t like about the PM banjo, most annoying first:
1) it’s hard to move and position. The part that rides on the ways is quite thin, so it doesn’t slide easily. This despite constant cleaning and lubricant.
2) I get a lot of vibration. I don’t think it’s very rigid.
3) it’s wide and has a dogleg. This combined with the backwards leaning tail stock means I frequently have trouble using tail stock due to interference with banjo.
 
As others have said call OneWay. The other important dimension is if the banjo will have enough length to turn a 20” bowl.
Yes, the bottom leg length is important. If you do a lot of large diameter pieces you may be better off with the Oneway 20" banjo.
Of course you still will have the PM unit.
 
Well, first thing I would ask is why do you need an upgrade? The 3520C has the wedges, similar to the Robust lathes which pinch the tool rest into the banjo. While not perfect, this system does work very well. With standard handles to lock the tool rest in place that use only one set screw, they do tend to slip unless I crank them way down tight. If the wedge system could be improved, for me, I would want it to be made from square stock rather than round so they don't pivot when you pull the tool rest out and put another one in. Hard to drill a square hole, but it can be done. Maybe a key way would work better for the wedges to fit into.

robo hippy
 
If you want to use specific tall tool rests go for the 16". If you haven't had a problem with the rigidity of your Powermatic banjo at only 1/4" taller the 16" should be fine.

I really like the Oneway banjos. What don't you like about the Powermatic?
A coupe of years ago I looked into getting a second 3520 banjo, which I had seen advertised some months before for a reasonable price. By the time I got around to this they were no longer advertised as a complete unit, only available as separate component parts -- the base casting, the axle, the gripping disc, so on. The casting by itself was over $600. I called Oneway, who sold me one for about $400US, it was delivered about a week later.
The Oneway banjo is narrower than the Powermatic, so you have to be careful when trying to turn it around near the bed gap -- it tends to fell in on one side, a bit awkward, but still it works just fine overall. Powermatic isn't the most customer-friendly outfit.
 
I called Oneway. The gentleman I spoke with said that theoretically the 20” banjo is more rigid, but they usually sell the 16” for the 3520 and haven’t had any complaints. He also noted that the 16” banjo is longer than the 20” to accommodate 24” outboard turning.
 
I have a 3520B and have used the 16" Oneway banjo for about 4 years.
The 20" Oneway banjo is noticeably heavier and longer than the 16" and probably heavier than the Powermatic.
The 16" Oneway is about 35% lighter than the Powermatic model B and will allow you to get closer to the tailstock and centerline of the lathe. If you want to turn spindles smaller than 2" in diameter, I believe you would be unhappy with the 20".

As for holding position, in a 10-sample test, the torque required to move the Oneway averaged 10-15% higher than the Powermatic, similar force applied to the clamping handles. The Oneway clamping pressure in PSI may be 3-4 times higher due to the difference in came action, length of handle and contact surface area. The Oneway cam action is unique (refer to Oneway info) and has about 1/3 the lift in 180 degrees of rotation as compared to Powermatic a definite mechanical advantage. The Oneway handle is also longer.

The important points:
The Oneway tool rest clamp would hold the torque against a chrome socket, 30 ft. lb. range. Powermatic required grinding a cap screw to a point to lock in the hole for the socket retention ball.
In the 10 test samples, the initial torque for the Oneway varied less than 10%, Powermatic about 20%.
After the first movement of the Powermatic banjo, a reapplication of torque and about 30% the time there was a fall off of torque. A third application and in 2 cases the banjo was loose after movement detected. The Oneway remained pretty much solid through the 3 torque applications.
The Powermatic cam action is supported at each end of the banjo and can deflect when it is not at either end. The torque measurements were made at the middle of the powermatic cam action. Both banjos were measured the same offset distance from spindle centerline to tool rest opening centerline. A disadvantage for Powermatic.
With a similar force exerted on both banjo locking handles, the Oneway was close to requiring a 2 handed jerk :oops: to release.
 

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The potential of a slipping banjo is unthinkable.
I would go with the large Oneway and replace a few tool-rests as needed. If you use straight tool-rests, give James Johnson in Kerrville, TX a call - he makes the best.
 
A question here , well ok two questions. Mentioned that OW handle is longer and personally I do not like it. Have not looked but I think the handle for PM could be procured in longer lengths? In the PM lock would a brass tipped screw on the handle hold better against the toolrest?
 
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