I Got a Question, Need advice - Turners

Paul Douglass

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I'm working on a prototype wheel for a little cart. It is around 9.5 inches in diameter. I want to part off the outside portion shone where the arrows are in the first picture. Is it safe to do that on the lathe? There are 8 spokes (wooden dowels) going from the part I want to art off into a hud. Second picture shows the holes drilled for the spokes to go through and to the hub. Any suggestions on a better way to part that off is it wouldn't be safe to do it on the lathe?
 

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The problem with parting off the outside part of a round piece like that is once if becomes detached, there's nothing to hold it in place. On something small like a bracelet, that's not a real big issue...the piece just stays on the shank of the turning tool. With bigger pieces, though, the loose piece can go airborne. This is what can happen when a piece goes airborne...I was parting off the circle from the inside of a donut chuck:

Donut%20Chuck%202%20500.jpg


My suggestion would be to almost part it off all the way through, then remove it from the lathe and finish the cut with a jigsaw or scroll saw.
 
Thanks, I was leary about it, that's why I asked. I've parted lots of smaller thing with no problems, but this is pretty big. You have a good idea on it. Another thing I could do I guess is make a circle jig for a router but I hate to go to that much trouble for something I don't know if it will work when I get done.
 
You could clamp a couple of guides to the bed that would ensure the wheel couldn't leave the rim once parted off.

I had a live chuck in the tailstock to help support it, so it couldn't have left the lathe. I guess I was more concerned, being I had 8 spoke holes drilled through it that I would get a bad catch and break a wrist or something. I'm a little gun shy right now, just recovering from a nasty kick back on the table saw, from being stupid.
 

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Paul is there any chance you could turn a disc from some layers of MDF sized large enough to create a cavity into which you could jam fit your wheel. What I am trying to describe is a three layer MDF jig. Two layers are discs glue solidly together. The third layer is a circle of MDF layers thick enough to accommodate your wheel glued to the face of the two layers glued together. This whole contraption should be mounted on a face plate and trued up on the outside diameter. Then the internal diameter of the circles should be carefully sized so that the wheel can be jammed inside and held securely.

I cannot tell if you have sufficient clearance around your disc for the disc to swing freely and not hit the lathe ways. If you could do that and apply a little tape to the outside edge of the wheel overlapping the MDF and a screw or two to the center of the wheel blank disc neither would go anywhere when you parted them. I would make a wide parting cut working it down gradually so there is no chance of binding when you finally cut through the wheel blank.

Since you are making multiple wheels the jig could be used over and over. A hole or two around the inside of the MDF circles would allow you to tap the jam fit wheel out from the back side.

I doubt any of this makes sense.....Maybe someone can do a better job of explaining it.
 
Mike, I understand what you are describing and I could probably squeeze it on the lathe. I have a little over 6" clearance. I have a 1' X 12" pine board, might make a good jam chuck out of.
 
That is a very akward way to try to make a spoked wheel. DAMHIK :eek:
Spoked wheels are correctly made in two halves with the wood rims cut on a bandsaw and the spokes attached to the hub first then the rim halves added. Once together and secured, the wheel can be put on a lathe to true up for roundness. Securing can be done several ways depending on what the item is and the period correctness you are trying to achieve. A lot of research can be involved making your first wheels.
I would not attempt the part you are asking about.
 
Well, actually wooden wheels are made up of any number of felloes, spoke, a hub and a steel tire. There is at least one spoke per felloe. Spokes do not usually pass through the felloe and are just inserted/driven into holes bored in the felloe.

The wheel is actually held together by the iron tire which is sized so that when it is heated it can be driven on the wooden wheel and upon cooling it will shrink and squeeze all the parts together tightly.
 
Mike, kinda used that method before. Least the same principle. May have to go back to it.

Thanks everyone for the input. Not quite sure how I will proceed yet, but I will...
 

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Paul is there any chance you could turn a disc from some layers of MDF sized large enough to create a cavity into which you could jam fit your wheel. What I am trying to describe is a three layer MDF jig. Two layers are discs glue solidly together. The third layer is a circle of MDF layers thick enough to accommodate your wheel glued to the face of the two layers glued together. This whole contraption should be mounted on a face plate and trued up on the outside diameter. Then the internal diameter of the circles should be carefully sized so that the wheel can be jammed inside and held securely.

I cannot tell if you have sufficient clearance around your disc for the disc to swing freely and not hit the lathe ways. If you could do that and apply a little tape to the outside edge of the wheel overlapping the MDF and a screw or two to the center of the wheel blank disc neither would go anywhere when you parted them. I would make a wide parting cut working it down gradually so there is no chance of binding when you finally cut through the wheel blank.

Since you are making multiple wheels the jig could be used over and over. A hole or two around the inside of the MDF circles would allow you to tap the jam fit wheel out from the back side.

I doubt any of this makes sense.....Maybe someone can do a better job of explaining it.

Thank you, Mike. It worked great for mounting the rim to clean up the inside and sand it smooth and round. I didn't part the rim off in the jam chuck, I took it to the scroll saw, cut it of and them put it in the jam chuck, turned it smooth and sanded it. My prototype is working so well it may become a used wheel. Hope I can duplicate it.
 

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My little cart wheel assembled. Does it remind anyone of Tinker Toys? I'm amazed how true it turns and with a little more care it will be straight as an arrow. I've been trying to think of some hose or a rubber belt I could put around it for rubber tread. Haven't found that yet.
 

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My little cart wheel assembled. Does it remind anyone of Tinker Toys? I'm amazed how true it turns and with a little more care it will be straight as an arrow. I've been trying to think of some hose or a rubber belt I could put around it for rubber tread. Haven't found that yet.
I'm a little late to this party my friend but did you find your tread yet? If not, how close (over/under) to 9.5" is the OD?

Is this one of your toys to be admired or used?

Anyways .... look here (number 447 or 448) http://www.rocketseals.com/catalog/o-rings-and-seals-for-u-s-measurements/o-rings/o-ring-size-chart?page=14

Not sure what the forum policy is about posting links to items and if I've stepped out of bounds I apologize and feel free to slap Paul in the face for me helping a friend <G>
 
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