Bob Cleek

I don't think they edge-set those planks with a big travel steam iron, though!
 

I read somewhere, but can't recall where, that there were more than a few broken ankles caused by cannon balls coming adrift and rolling across the decks. Getting whacked in the ankle with a rolling cannon ball would have to smart a bit, I'd expect!
 

From the photos and what little information is on the Mantua website, it certainly doesn't look like much for the money and the price doesn't include the power supply you have to buy separately. I may be wrong, but judging by the picture, it's little more than a toy. Given what they are asking for it, one could buy a decent entry level scroll saw new and probably pick up a very good one on the used market. (Lots of people buy scroll saws and then abandon the hobby they bought it for.) There's a world of difference between a bottom-end scroll saw and a top-of-the-line one and good reasons why the best are so much more expensive than the least of them. I'd look for something more substantial. If money is a consideration, spend what you would have on the Mantua and its power supply to buy a good used one. I think you'll be glad you did.

Naw, I'd award that prize to the chainsaw. Fact is, all tools are dangerous and forgetting that is the major cause of injuries.
 
The liability insurance bean counters will tell you that the tool that sends more people to the emergency room than any other is the ladder. No kidding. That's a fact.

What I meant was that if you wanted to cut pieces of wood all exactly the same length, the sled does that very easily. If you want to cut perfect miter angles, the sled does that better than using the miter gauge on the table saw and poses less risk of your touching the moving blade.

You'd think so, but actually they are made of "Luxite," K&E's trade name, which is apparently a type of plexiglass plastic material. The early curves were made of boxwood, ebony, and pearwood. In the mid-1800's, some were made of hard rubber.
 
They were essential to drafting plans in naval architecture, aviation, and automobile design before CAD became available and, even now, only the most sophisticated (and expensive) CAD programs are capable of approaching what Copenhagen curves can do, often much easier and faster than CAD, as well. CAD caused a drop in demand for them below what was necessary to make producing them profitable. Demand for mechanical drafting and surveying instruments dropped dramatically as the industry "went digital" and K&E filed for bankruptcy in 1982. The trade name was purchased by others, but nothing was done with it and that was the end of the high-end drafting instrument industry in the U.S, at least. The European manufacturers lasted only a few years beyond that. There's always been a demand for manual drafting instruments, and when the sources dried up, the value of existing instruments eventually skyrocketed when collectors entered the used instrument market. Curves sets, first marketed by Keuffel and Esser right after the Civil War, were never inexpensive. While they may not appear so, they are precision instruments that must exactly replicate mathematically defined fair curves. One fellow attempted recently to produce Copenhagen curves as a "Go Fund Me" business, but failed to get enough financial support to pay for the tooling to commence production. Complete sets are very difficult to find these days and people do pay a lot of money for the few sets that come up for auction now and again. A CAD program that can come close to what can be done manually with curves will set you back a lot more than what the curves are going for now and likely require a steep learning curve to master.

Here is the 'official' complete set:

I'd use my bench sander for that. Cut close to length using my razor saw then sand the miters. Much safer. Having said that, the Byrnes saw with sled is on my "saving up" for list. 
 
As to general safety, I've only twice needed stitches; once from using a box cutter, the other in the kitchen cutting a water melon. I've also fallen off a ladder! 
 
My total paranoia about power saws has allowed me to keep all my fingers and my hatred of heights kept my fall to about 4 feet.
 
 

What I meant was that if you wanted to cut pieces of wood all exactly the same length, the sled does that very easily. If you want to cut perfect miter angles, the sled does that better than using the miter gauge on the table saw and poses less risk of your touching the moving blade.

The advantages of the cross-cut sled on the Byrnes saw are the same as for a sled on a full-size table saw. When making cross cuts, the sled provides greater safety and accuracy, particularly when making mitered cuts and cutting multiple pieces to exactly the same length. A cross-cut sled makes perfect, repeatable crosscuts on a table saw without tear-out, which is something the modeler needs to do on a fairly regular basis. Because both the workpiece and the offcut move with the sled and are backed by a fence perpendicular to the blade, there's much less chance of kickback and blowout as the blade exits the cut.  The Byrnes sled has a metal box which covers the blade as the cut is completed. This is a very good "automatic" safety feature that prevents ever getting cut by the blade as the sled is pushed forward.
 
The Byrnes saw sled is machined to the same .001" tolerances as the saw itself, so, while building your own sled is conceptually easy, incorporating the highly accurate miter gauge of the Byrnes sled in one you build yourself is going to take some doing. Building a sled for your full-size table saw doesn't require the tolerances that making one that will give you what your Byrnes saw is capable of would demand in terms of accuracy. While anything done on a sled can also be done without the sled, the sled saves set-up time, especially with repetitive cuts. It also keeps your fingers away from the blade, which is particularly important when cutting small pieces.
 
Check out this video. It's for full-size table saws, but if you turn your volume down, you can pretend he's talking about a Byrnes saw.
 
 

What I meant was that if you wanted to cut pieces of wood all exactly the same length, the sled does that very easily. If you want to cut perfect miter angles, the sled does that better than using the miter gauge on the table saw and poses less risk of your touching the moving blade.

You and me both! I've also got complete sets of K&E French curves, engineers' curves, and "railroad" and "highway" radius curves. I've got a fair number of "doubles" to the ship's and French curve sets. I had to buy "odds and ends" in lots before I got all of them. I built them up over a period of three years or so when the stuff started appearing on eBay and before collecting it got really popular. I built quite a collection of top-of-the-line K&E Paragon drafting instruments. It started when I first bought a K&E Paragon planimeter to calculate displacement and I went downhill from there.  I finally "admitted I had a problem" and "got into rehab" when the prices started climbing exponentially. 
 

Somebody's selling an extremely rare complete cased set of Keuffel and Esser "Copenhagen" ship's curves on eBay. (Not me. I've no dog in the fight. I already have a set.) I thought some MSW forumites might be interested in seeing what a set looks like.
 
Similar to "French curves," these "mathematically shaped" curves are used in the same manner as "French curves" by naval architects to draw fair curves when drawing ships' lines. Sometimes called "Copenhagen curves," when used in conjunction with one another to join points laid out on the drafting board, they will permit drawing a fair curve of any shape whatsoever.  Dealt a death blow by CAD, like a lot of essential manual drafting instruments, they are no longer made and are unobtainable on the retail market. The perfect gift for the scratch-builder who has (almost) everything! A steal at a "buy it now" price of only $600! (Insert "sarcasm" emoji here.)  https://www.ebay.com/itm/Lot-of-56-Keuffel-Esser-Co-1864-Ship-French-Drafting-Curves-With-Box/183690539257?hash=item2ac4cf30f9:g:9tcAAOSwGFZcae~q
 
Thirty-one "watchers" and nobody's bought it yet. It'll be interesting to see what it ultimately brings when the seller wises up (or gets lucky.) It's worth watching (click on the "watch" feature to track it) to see what happens. I'd have guessed it would have been priced between two and three hundred, at most. The collectors can get crazy sometimes, though. I didn't pay anywhere near that for my used set, but that was years ago before manual drafting instruments became hard to find and highly collectible. There was a brief moment in time right after everybody went over to CAD and had no interest in manual instruments when even the finest manual instruments in mint condition could be bought for peanuts. Like vinyl records, the advantages of manual instruments have been rediscovered and are now highly prized by collectors and users alike.
 
 
 

You'd think so, but actually they are made of "Luxite," K&E's trade name, which is apparently a type of plexiglass plastic material. The early curves were made of boxwood, ebony, and pearwood. In the mid-1800's, some were made of hard rubber.
 
They were essential to drafting plans in naval architecture, aviation, and automobile design before CAD became available and, even now, only the most sophisticated (and expensive) CAD programs are capable of approaching what Copenhagen curves can do, often much easier and faster than CAD, as well. CAD caused a drop in demand for them below what was necessary to make producing them profitable. Demand for mechanical drafting and surveying instruments dropped dramatically as the industry "went digital" and K&E filed for bankruptcy in 1982. The trade name was purchased by others, but nothing was done with it and that was the end of the high-end drafting instrument industry in the U.S, at least. The European manufacturers lasted only a few years beyond that. There's always been a demand for manual drafting instruments, and when the sources dried up, the value of existing instruments eventually skyrocketed when collectors entered the used instrument market. Curves sets, first marketed by Keuffel and Esser right after the Civil War, were never inexpensive. While they may not appear so, they are precision instruments that must exactly replicate mathematically defined fair curves. One fellow attempted recently to produce Copenhagen curves as a "Go Fund Me" business, but failed to get enough financial support to pay for the tooling to commence production. Complete sets are very difficult to find these days and people do pay a lot of money for the few sets that come up for auction now and again. A CAD program that can come close to what can be done manually with curves will set you back a lot more than what the curves are going for now and likely require a steep learning curve to master.

Once you have the hatch coming piece positioned on the sled - against the stops - hold it down with a large piece of wood with a hollow that just fits the coming - maybe even involve double sided tape - to keep your fingers away from the blade.  You can even form the hollow from two pieces of wood  and the tape so that you can reuse the cover piece for different sized stock.  A few extra minutes spent on safety can save a lot of time spent on healing.  I think that a table saw is about as dangerous as it gets for a motorized cutting tool.

Are they made of crystal?   

Well, YT, you must have a very steady hand! I find the long curves very useful for laying out spiled planks.

Somebody's selling an extremely rare complete cased set of Keuffel and Esser "Copenhagen" ship's curves on eBay. (Not me. I've no dog in the fight. I already have a set.) I thought some MSW forumites might be interested in seeing what a set looks like.
 
Similar to "French curves," these "mathematically shaped" curves are used in the same manner as "French curves" by naval architects to draw fair curves when drawing ships' lines. Sometimes called "Copenhagen curves," when used in conjunction with one another to join points laid out on the drafting board, they will permit drawing a fair curve of any shape whatsoever.  Dealt a death blow by CAD, like a lot of essential manual drafting instruments, they are no longer made and are unobtainable on the retail market. The perfect gift for the scratch-builder who has (almost) everything! A steal at a "buy it now" price of only $600! (Insert "sarcasm" emoji here.)  https://www.ebay.com/itm/Lot-of-56-Keuffel-Esser-Co-1864-Ship-French-Drafting-Curves-With-Box/183690539257?hash=item2ac4cf30f9:g:9tcAAOSwGFZcae~q
 
Thirty-one "watchers" and nobody's bought it yet. It'll be interesting to see what it ultimately brings when the seller wises up (or gets lucky.) It's worth watching (click on the "watch" feature to track it) to see what happens. I'd have guessed it would have been priced between two and three hundred, at most. The collectors can get crazy sometimes, though. I didn't pay anywhere near that for my used set, but that was years ago before manual drafting instruments became hard to find and highly collectible. There was a brief moment in time right after everybody went over to CAD and had no interest in manual instruments when even the finest manual instruments in mint condition could be bought for peanuts. Like vinyl records, the advantages of manual instruments have been rediscovered and are now highly prized by collectors and users alike.
 
 
 

Little more:

I feel your pain, Bob. Current prices certainly make for attitude adjustment. I also have a lovely pearwood set of radius curves 3" to 200". Those earlier, heady days of eBay, when bargains could still be had! I still occasionally look and whimper softly.

Somebody's selling an extremely rare complete cased set of Keuffel and Esser "Copenhagen" ship's curves on eBay. (Not me. I've no dog in the fight. I already have a set.) I thought some MSW forumites might be interested in seeing what a set looks like.
 
Similar to "French curves," these "mathematically shaped" curves are used in the same manner as "French curves" by naval architects to draw fair curves when drawing ships' lines. Sometimes called "Copenhagen curves," when used in conjunction with one another to join points laid out on the drafting board, they will permit drawing a fair curve of any shape whatsoever.  Dealt a death blow by CAD, like a lot of essential manual drafting instruments, they are no longer made and are unobtainable on the retail market. The perfect gift for the scratch-builder who has (almost) everything! A steal at a "buy it now" price of only $600! (Insert "sarcasm" emoji here.)  https://www.ebay.com/itm/Lot-of-56-Keuffel-Esser-Co-1864-Ship-French-Drafting-Curves-With-Box/183690539257?hash=item2ac4cf30f9:g:9tcAAOSwGFZcae~q
 
Thirty-one "watchers" and nobody's bought it yet. It'll be interesting to see what it ultimately brings when the seller wises up (or gets lucky.) It's worth watching (click on the "watch" feature to track it) to see what happens. I'd have guessed it would have been priced between two and three hundred, at most. The collectors can get crazy sometimes, though. I didn't pay anywhere near that for my used set, but that was years ago before manual drafting instruments became hard to find and highly collectible. There was a brief moment in time right after everybody went over to CAD and had no interest in manual instruments when even the finest manual instruments in mint condition could be bought for peanuts. Like vinyl records, the advantages of manual instruments have been rediscovered and are now highly prized by collectors and users alike.
 
 
 

You and me both! I've also got complete sets of K&E French curves, engineers' curves, and "railroad" and "highway" radius curves. I've got a fair number of "doubles" to the ship's and French curve sets. I had to buy "odds and ends" in lots before I got all of them. I built them up over a period of three years or so when the stuff started appearing on eBay and before collecting it got really popular. I built quite a collection of top-of-the-line K&E Paragon drafting instruments. It started when I first bought a K&E Paragon planimeter to calculate displacement and I went downhill from there.  I finally "admitted I had a problem" and "got into rehab" when the prices started climbing exponentially. 
 

Somebody's selling an extremely rare complete cased set of Keuffel and Esser "Copenhagen" ship's curves on eBay. (Not me. I've no dog in the fight. I already have a set.) I thought some MSW forumites might be interested in seeing what a set looks like.
 
Similar to "French curves," these "mathematically shaped" curves are used in the same manner as "French curves" by naval architects to draw fair curves when drawing ships' lines. Sometimes called "Copenhagen curves," when used in conjunction with one another to join points laid out on the drafting board, they will permit drawing a fair curve of any shape whatsoever.  Dealt a death blow by CAD, like a lot of essential manual drafting instruments, they are no longer made and are unobtainable on the retail market. The perfect gift for the scratch-builder who has (almost) everything! A steal at a "buy it now" price of only $600! (Insert "sarcasm" emoji here.)  https://www.ebay.com/itm/Lot-of-56-Keuffel-Esser-Co-1864-Ship-French-Drafting-Curves-With-Box/183690539257?hash=item2ac4cf30f9:g:9tcAAOSwGFZcae~q
 
Thirty-one "watchers" and nobody's bought it yet. It'll be interesting to see what it ultimately brings when the seller wises up (or gets lucky.) It's worth watching (click on the "watch" feature to track it) to see what happens. I'd have guessed it would have been priced between two and three hundred, at most. The collectors can get crazy sometimes, though. I didn't pay anywhere near that for my used set, but that was years ago before manual drafting instruments became hard to find and highly collectible. There was a brief moment in time right after everybody went over to CAD and had no interest in manual instruments when even the finest manual instruments in mint condition could be bought for peanuts. Like vinyl records, the advantages of manual instruments have been rediscovered and are now highly prized by collectors and users alike.
 
 
 

For those with a collector's taste, acquiring a classic Keuffel & Esser boxed set of "scales," as they are properly called, might be a joy.  The complete boxed sets in good condition are somewhat rare and bring a premium, but single rules are frequently offered and sell at quite reasonable prices on eBay. The old-fashioned boxwood versions bring more than the "modern" and now-obsolete plastic ones designed for use with "drafting machines." Metal versions are also made. 1/8, 1/4, 1/2, and 3/4 inch to the foot scales are pretty common.
 
   

Very handy site!