Coring system for lathe with almost 32" swing

[Pete Danielson]

I have a lathe with nearly 32" swing and was looking at the Oneway coring system, but it only accommodates lathes up to a 26" swing. Is anyone familiar with a system that would work with my lathe?

I do metal work as well so I'm comfortable fabricating/modifying an existing system to work, just not sure exactly what's involved or what issues I need to be aware of since I've never used a coring setup before.

 

[Richard Coers]

Just fabricate a spacer system to effectively raise the Oneway bed mounted parts up so it is on center. Remember that torque goes up exponentially as you get further away from the center line.

 

[Pete Danielson]

Making a riser block was my initial thought. I reached out to oneway to ask about that, but haven't heard back. Another supplier I contacted advised against doing that so I didn't know if there was some potential issue I wasn't aware of. Probably just a liability issue.

 

[Paul Paukstelis]

I have a lathe with nearly 32" swing and was looking at the Oneway coring system, but it only accommodates lathes up to a 26" swing. Is anyone familiar with a system that would work with my lathe?

I do metal work as well so I'm comfortable fabricating/modifying an existing system to work, just not sure exactly what's involved or what issues I need to be aware of since I've never used a coring setup before.

Is it a "true" 32" swing lathe, or something like the Rikon that has a sliding bed? If is a sliding a bed, you want to get the system that fits your smallest swing, not the largest.

 

[Pete Danielson]

It's a German lathe made by Hapfo, no sliding bed. The spindle height is @ 403mm so the swing is about 31-3/4.

 

[robo hippy]

You might have to make your own, especially if you are going any where near that bit. I know New Holland Bowl mill has a coring system for bowls that size, and Ronald Kane from Holland had one made Other than that, Oneway is stable all the way to the end of the biggest core you can remove.

robo hippy

 

[Dean Center]

It seems to me that the additional height will substantially add to the stress on the coring rig due to the longer lever arm. Simply raising a factory made rig won't take that into consideration. The guys at Oneway had to consider that when they made their taller set ups. I bet they would enjoy the question and be happy to give you their experience, maybe even their calculations. The base components of a Oneway coring set up aren't very complicated, so fabricating something with larger base plate/clamp blocks and/or increased diameter supports to hold up the standard knives wouldn't be too hard, if you have metalworking ability.

Oops. Hadn't thought about making a 28" core and the knife needed. I'd have no clue about the knife part of making your own if you're going to max out the size of the cores. What would somebody do with a 27" bowl???

 

[DON FRANK]

If the goal is to use standard coring knives from oneway then fabricating higher riser bars will do that and do that safely. Use heavy walled tubing the correct I/S diameter and weld gussets to the base because of the raised height. My lathe is 26" spindle height and it works fine.
If the goal is to be able to core bowls larger than the #3 or #4 knives i would rethink things. I would not want to try to fabricate larger knives from a safety issue.

 

[Pete Danielson]

I only plan to use the standard coring sizes. I imagine any requests for bowls in the 28-30" range will be unlikely to extremely rare so I'll cross that bridge if the time ever comes.

I reached out to oneway through the messaging portal on their website last weekend, but still haven't gotten a response. Doesn't matter, I'll go ahead with that system and fabricate a riser. I have a full metal shop so it's not a big deal, just wanted to get some input from those familiar with coring systems in case there was any issues I was overlooking due to my lack of experience. Thanks for the feedback.

 

[Darryl Fective]

It's a German lathe made by Hapfo, no sliding bed. The spindle height is @ 403mm so the swing is about 31-3/4.

I'd love to see photos. That's too damn cool to not share.

 

[DON FRANK]

Pete, the main considerations are to be sure your new posts are thick walled tubing and the tolerance pretty close for the post of the cutting knife. You don't want any side to side slop. The bottom of the knive posts have an adjustable bolt used to set the height. You could cut a solid round piece of steel the correct length and drop it into the upright tube to get close and then dial it in with the bolt. The cutter height needs to be dead center of your spindle height. If you order a standard oneway system you could simply cut the upright tube and weld a solid spacer below for the correct height. If you are ordering it direct from oneway you might ask if you can get the uprights before they have been powder coated. That way you don't have to grind or sandblast the paint off.

When you get things working at some point consider springing for the Hunter cutting tip for the one way system. They are expensive but worth the money. They cut twice as fast as the oneway design.

 

[DON FRANK]

I just saw on the for sale section of this forum someone has a set of 18" posts available. You might be able to purchase these if oneway will sell you just the other components you would need and save a little money.