Bob Cleek

Not sure, I understand correctly what the problem is - picture would be helpful, but it sounds, as if the workpiece has not been clamped down properly.
 
In general, lathe or mill, if the workpiece can flex or otherwise move, you will not get satisfactory results or it may even result in desaster.

Two additional comments on the above:
 
- rotate the rotary table always against the rotational direction of the mill ! These rotary tables are not actually meant for round-milling, but for indexing. If you rotate the table the other way around, the mill can grap the workpiece and wrench it from your hand. For this reason it is also advisable to let the locking knob slightly bind, so that there is a bit of frictional resistance. That helps to steady the movement.
And: do not try to do this kind of operation with metal ! Real rotary table built for round-milling have a self-locking worm-drive.
 
- I would make the first cut a bit wider (on the outside) and narrower (on the inside) and go for second, finishing pass.

As a matter of fact, this ring of wedges would not normally be visible. It is waterproofed by a sleeve of painted/tarred canvas that is nailed to the mast and to the deck. It may also be fastened to the mast by a rope wound around it.

It's certainly coming along nicely!  It's good you buttoned her up with plenty of insulation and "creature comforts." It always pays to have a workshop that you can use to sleep in on those occasions when you're thrown out of the house.  
 

See the sticky post at the top of this forum section. It will answer all your saw blade questions. Jim Byrnes can tell you which blades you'll need depending upon what you plan to do with the saw. 
 
 

All of those accessories above are very useful. I'd urge anyone to get them all at the time you buy the saw. I expect you'd save a good bit of money on shipping charges if it were all shipped together. The sliding table may seem like a chunk of money, and it is, but it's really worth it. You can build your own, but if you want to replicate the accuracy the saw is capable of with a sliding table, get the factory-made one. It's a beautiful piece of machining, too. 

It's a lot easier to use a drawplate, which will give you a perfectly uniform diameter of whatever size you desire.
 

 
Byrnes Model Machines (Makers of the Byrnes saw) offers a drawplate which produces very fine round material.
 

 
They are also available in any number of shapes, such as squares, rectangles, half-rounds, and so on.
 

 
 

That sounds like a hard way to do it. I take a mandrel ("stick") of the proper inside diameter of the mast hoop I want to make and wrap a piece of plastic kitchen wrap around it so glue won't stick to it.  Then I take a nice straight grained piece of wood and plane six or eight inch shavings off the edge of it. Then, applying PVA glue as I go, I wrap the shavings tightly around the mandrel and fasten them with a rubber band and let the glue set. After the glue is dry, I mount the mandrel on my lathe and sand the face of the shavings fair, then I part off the rings with a knife or jeweler's saw, leaving the hoops on the mandrel as I go. I then round the outer edges of the hoops with a file on the lathe if needed or just lightly sand to knock off he corners, depending on what I want it to look like. I then slide the rings off the mandrel and clean up the inner faces and edges with a bit of sandpaper by hand. This method produces hoops made of fine laminations which will not break on the grain, as do hoops cut from any sort of sheet material. They are also made exactly as real mast hoops are made. (In larger scales, small headed brass pins can be used to represent the rivets that hold steam-bent laminated hoops together.)

Wikipedia is your friend. "A thousand words is worth a picture." https://en.wikipedia.org/wiki/Mandrel
 

There are lots of different types of mandrels. What I was talking about was simply a stick mounted between lathe centers, or even held vertically in a drill press chuck. The diameter of the stick would be the same as the inside diameter of the "ring" or hoop you wanted. Once the plane shavings are wrapped around the stick with glue and dry, they make tiny little laminated wood rings, like plywood. You spin the stick and sand the wrapped and glued shavings smooth, then cut them apart to the width you want using a jeweler's saw with the blade pressed against the spinning "stick" to cut a perfect circle around the glued shavings to separate the "rings" or hoops from the larger glued shavings rings on the stick. They you slide the rings off the stick. Make sense?
 
It was in response to a post about making mast hoops, A "mast cap" is the little "button" at the very top of a mast. A mast "boot" is a canvas or leather "skirt" lashed at the top around the mast and at the bottom around a trim ring at the deck which prevents water from running down the mast and leaking below. 
 
"A little more ornate mast cap at the base of the mast on the deck" would apparently refer to the trim ring over which the mast boot was lashed, so there wouldn't be a lot of point to an "ornate one."  Sometimes, however, the rings have a groove or recessed band around their circumference to permit the lashing to hold better.
 
If you want an easy way to make one, I'd suggest you take a suitably sized square block of wood with the grain running lengthwise and drill a hole the size of the hole you want in the middle of the ring into the middle of the block of wood. then, since you don't have a four jawed chuck, mount the block of wood on your three jawed chuck with the jaws inside the hole you've drilled in the block. Then turn the block to the outside diameter of the entire ring you want, and part off the thickness of the ring you want. If you want it "ornate," you can easily shape the outside edge of the ring however you want before parting it off the block/tube you've got mounted on your chuck. Drill the hole in the center deep enough and you can cut a number of perfectly matching rings from the "tube" you've made. This is entirely a lathe operation, but I think it's a lot faster and easier, and perhaps safer, than doing  the job with a mill and certainly requires less expensive tooling. 
 
"Anyone have an example or a source/reference I can look to?" "These all sound like nice ideas, but I’m not sure I follow the narrative description."  As with most things technical, nomenclature is important. Maritime nomenclature is further complicated by the different names for the same things in different languages, and even in different nations with the same language. (As with an automobile "trunk" and "hood" in American English which are called the "boot" and "bonnet" in British English.) Like any language, you have to spend time around people who speak it in order to learn it. It's true with machining, too. A "chuck" isn't a "holder" and "parting" is cutting off a machined piece from a larger hunk of metal spinning in a lathe. It's quite difficult to write instructions for how to make something when the writer and the reader are using different terms for what is being made and how it is being made! You will find your mill (and lathe, even more so) an amazingly handy machine once you learn how to use it properly.
 
There are many good instructional books and videos available.  Here are the public-domain U.S. Army training manuals for lathes and mills. I'd suggest you print them out and put them in a binder for reference. They're very handy and nobody teaches people without any prior knowledge how to do things better than the military.  Here's the manual on lathes:  https://www.americanmachinetools.com/how_to_use_a_lathe.htm  Here's the one on milling machines: https://www.americanmachinetools.com/how_to_use_a_milling_machine.htm  These address large machines, but the principles and procedures are the same for machines of any size.
 
Another wonderful resource are the YouTube videos by a fellow who calls himself "Tubalcain" or "Mr.Pete222." He's a retired metal shop teacher who has continued teaching on YouTube. His practical instruction is great and his presentation is entertaining. He's got hundreds of videos on everything under the sun to do with the old-time machinists' craft.
 
I'd offer a word of caution. Even though modelers work with small lathes and mills, these are two of the more dangerous machines in any shop. (The lathe is probably the most dangerous machine tool of all. Table saws account for more visits to the emergency room, but only because there are so many more of them in amateur hands.) If you aren't formally trained in machine shop operational safety, pay particular attention to the safety warnings in the written materials before trying anything on the machines. Rule number one, for drill presses, mills, and lathes: Never, ever, leave a chuck key in a chuck. Make it a habit to keep chuck keys in a separate place and when taken from that place, never let them leave your hand unless you are putting them back in their place. (A flying chuck key is a dangerous missile. ) Rule number two: Always turn the machine or work piece by hand an entire revolution before turning the power on to make sure all work is securely mounted and there are no clearance obstructions. Rule number three: Make sure you have no long sleeves, neck ties or chains, or jewelry of any kind on. (These can become caught up in moving machine parts with catastrophic consequences.) These aren't the sum total of safety rules for machine tools, but they are the ones I've was yelled at the most about before I learned them well! 
 
 
 
 

All of those accessories above are very useful. I'd urge anyone to get them all at the time you buy the saw. I expect you'd save a good bit of money on shipping charges if it were all shipped together. The sliding table may seem like a chunk of money, and it is, but it's really worth it. You can build your own, but if you want to replicate the accuracy the saw is capable of with a sliding table, get the factory-made one. It's a beautiful piece of machining, too. 

It's certainly coming along nicely!  It's good you buttoned her up with plenty of insulation and "creature comforts." It always pays to have a workshop that you can use to sleep in on those occasions when you're thrown out of the house.  
 

See the sticky post at the top of this forum section. It will answer all your saw blade questions. Jim Byrnes can tell you which blades you'll need depending upon what you plan to do with the saw. 
 
 

All of those accessories above are very useful. I'd urge anyone to get them all at the time you buy the saw. I expect you'd save a good bit of money on shipping charges if it were all shipped together. The sliding table may seem like a chunk of money, and it is, but it's really worth it. You can build your own, but if you want to replicate the accuracy the saw is capable of with a sliding table, get the factory-made one. It's a beautiful piece of machining, too. 

Wikipedia is your friend. "A thousand words is worth a picture." https://en.wikipedia.org/wiki/Mandrel
 

There are lots of different types of mandrels. What I was talking about was simply a stick mounted between lathe centers, or even held vertically in a drill press chuck. The diameter of the stick would be the same as the inside diameter of the "ring" or hoop you wanted. Once the plane shavings are wrapped around the stick with glue and dry, they make tiny little laminated wood rings, like plywood. You spin the stick and sand the wrapped and glued shavings smooth, then cut them apart to the width you want using a jeweler's saw with the blade pressed against the spinning "stick" to cut a perfect circle around the glued shavings to separate the "rings" or hoops from the larger glued shavings rings on the stick. They you slide the rings off the stick. Make sense?
 
It was in response to a post about making mast hoops, A "mast cap" is the little "button" at the very top of a mast. A mast "boot" is a canvas or leather "skirt" lashed at the top around the mast and at the bottom around a trim ring at the deck which prevents water from running down the mast and leaking below. 
 
"A little more ornate mast cap at the base of the mast on the deck" would apparently refer to the trim ring over which the mast boot was lashed, so there wouldn't be a lot of point to an "ornate one."  Sometimes, however, the rings have a groove or recessed band around their circumference to permit the lashing to hold better.
 
If you want an easy way to make one, I'd suggest you take a suitably sized square block of wood with the grain running lengthwise and drill a hole the size of the hole you want in the middle of the ring into the middle of the block of wood. then, since you don't have a four jawed chuck, mount the block of wood on your three jawed chuck with the jaws inside the hole you've drilled in the block. Then turn the block to the outside diameter of the entire ring you want, and part off the thickness of the ring you want. If you want it "ornate," you can easily shape the outside edge of the ring however you want before parting it off the block/tube you've got mounted on your chuck. Drill the hole in the center deep enough and you can cut a number of perfectly matching rings from the "tube" you've made. This is entirely a lathe operation, but I think it's a lot faster and easier, and perhaps safer, than doing  the job with a mill and certainly requires less expensive tooling. 
 
"Anyone have an example or a source/reference I can look to?" "These all sound like nice ideas, but I’m not sure I follow the narrative description."  As with most things technical, nomenclature is important. Maritime nomenclature is further complicated by the different names for the same things in different languages, and even in different nations with the same language. (As with an automobile "trunk" and "hood" in American English which are called the "boot" and "bonnet" in British English.) Like any language, you have to spend time around people who speak it in order to learn it. It's true with machining, too. A "chuck" isn't a "holder" and "parting" is cutting off a machined piece from a larger hunk of metal spinning in a lathe. It's quite difficult to write instructions for how to make something when the writer and the reader are using different terms for what is being made and how it is being made! You will find your mill (and lathe, even more so) an amazingly handy machine once you learn how to use it properly.
 
There are many good instructional books and videos available.  Here are the public-domain U.S. Army training manuals for lathes and mills. I'd suggest you print them out and put them in a binder for reference. They're very handy and nobody teaches people without any prior knowledge how to do things better than the military.  Here's the manual on lathes:  https://www.americanmachinetools.com/how_to_use_a_lathe.htm  Here's the one on milling machines: https://www.americanmachinetools.com/how_to_use_a_milling_machine.htm  These address large machines, but the principles and procedures are the same for machines of any size.
 
Another wonderful resource are the YouTube videos by a fellow who calls himself "Tubalcain" or "Mr.Pete222." He's a retired metal shop teacher who has continued teaching on YouTube. His practical instruction is great and his presentation is entertaining. He's got hundreds of videos on everything under the sun to do with the old-time machinists' craft.
 
I'd offer a word of caution. Even though modelers work with small lathes and mills, these are two of the more dangerous machines in any shop. (The lathe is probably the most dangerous machine tool of all. Table saws account for more visits to the emergency room, but only because there are so many more of them in amateur hands.) If you aren't formally trained in machine shop operational safety, pay particular attention to the safety warnings in the written materials before trying anything on the machines. Rule number one, for drill presses, mills, and lathes: Never, ever, leave a chuck key in a chuck. Make it a habit to keep chuck keys in a separate place and when taken from that place, never let them leave your hand unless you are putting them back in their place. (A flying chuck key is a dangerous missile. ) Rule number two: Always turn the machine or work piece by hand an entire revolution before turning the power on to make sure all work is securely mounted and there are no clearance obstructions. Rule number three: Make sure you have no long sleeves, neck ties or chains, or jewelry of any kind on. (These can become caught up in moving machine parts with catastrophic consequences.) These aren't the sum total of safety rules for machine tools, but they are the ones I've was yelled at the most about before I learned them well! 
 
 
 
 

That sounds like a hard way to do it. I take a mandrel ("stick") of the proper inside diameter of the mast hoop I want to make and wrap a piece of plastic kitchen wrap around it so glue won't stick to it.  Then I take a nice straight grained piece of wood and plane six or eight inch shavings off the edge of it. Then, applying PVA glue as I go, I wrap the shavings tightly around the mandrel and fasten them with a rubber band and let the glue set. After the glue is dry, I mount the mandrel on my lathe and sand the face of the shavings fair, then I part off the rings with a knife or jeweler's saw, leaving the hoops on the mandrel as I go. I then round the outer edges of the hoops with a file on the lathe if needed or just lightly sand to knock off he corners, depending on what I want it to look like. I then slide the rings off the mandrel and clean up the inner faces and edges with a bit of sandpaper by hand. This method produces hoops made of fine laminations which will not break on the grain, as do hoops cut from any sort of sheet material. They are also made exactly as real mast hoops are made. (In larger scales, small headed brass pins can be used to represent the rivets that hold steam-bent laminated hoops together.)

I think I need pictures...

Bob
 
Perhaps mast hoops wasn’t the best example I could have cited for the technique - your’s is clearly better. Nevertheless it works. No Idea’s example is more appropriate. The method works well for most situations where you need to mill a circle or part 
thereof. 

It's certainly coming along nicely!  It's good you buttoned her up with plenty of insulation and "creature comforts." It always pays to have a workshop that you can use to sleep in on those occasions when you're thrown out of the house.  
 

See the sticky post at the top of this forum section. It will answer all your saw blade questions. Jim Byrnes can tell you which blades you'll need depending upon what you plan to do with the saw. 
 
 

I picked up almost the exact same saw at Harbor Freight for $25. I mounted it on a jig with a stop to make repetitive cuts faster and more accurate.

Job done

I know this doesn't really help you, but In the old days, they just gave us a big hunk of balsa, and the instructions "now, carve the block to the shape of the stern".
 
That said, you do have the shape of the deck and the side profile from the drawing. It's all covered up by planking, so you don't have to worry about how good it looks. It just has to be functional.

All of those accessories above are very useful. I'd urge anyone to get them all at the time you buy the saw. I expect you'd save a good bit of money on shipping charges if it were all shipped together. The sliding table may seem like a chunk of money, and it is, but it's really worth it. You can build your own, but if you want to replicate the accuracy the saw is capable of with a sliding table, get the factory-made one. It's a beautiful piece of machining, too. 

As said, aside for a thickness sander, disk sander, and perhaps a sanding drum, there's little use for sanding machines in modeling. The thickness and disk sanders for modeling really have to be specialty machines designed to work to very close tolerances. The thickness sanders perform the same function as a thickness planer in full-scale woodworking and a disk sander for modeling has to have a very accurate table and miter gauge. These specialty modeling machines work to tolerances of .001 and don't come cheap. (Byrnes are really the only ones worth spending the money  on, IMHO.) Proxxon and MicroMark market all sorts of powered modeling tools, but most all are overkill for ship modeling. Modelers cut pieces with jeweler's saws, small chisels, and hobby knives and scalpels, rather than shaping wood with sandpaper. In many instances, a scraper is the better tool than sandpaper in any event. Given the size of the work, there's no need for full-size sanders. Many is the part that's been ruined by an over-aggressive powered sanding machine. Finish sanding on models is done with paper in the grit ranges of 320 to 600, which doesn't work so well with power sanders, anyway.

As said, aside for a thickness sander, disk sander, and perhaps a sanding drum, there's little use for sanding machines in modeling. The thickness and disk sanders for modeling really have to be specialty machines designed to work to very close tolerances. The thickness sanders perform the same function as a thickness planer in full-scale woodworking and a disk sander for modeling has to have a very accurate table and miter gauge. These specialty modeling machines work to tolerances of .001 and don't come cheap. (Byrnes are really the only ones worth spending the money  on, IMHO.) Proxxon and MicroMark market all sorts of powered modeling tools, but most all are overkill for ship modeling. Modelers cut pieces with jeweler's saws, small chisels, and hobby knives and scalpels, rather than shaping wood with sandpaper. In many instances, a scraper is the better tool than sandpaper in any event. Given the size of the work, there's no need for full-size sanders. Many is the part that's been ruined by an over-aggressive powered sanding machine. Finish sanding on models is done with paper in the grit ranges of 320 to 600, which doesn't work so well with power sanders, anyway.