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Im wonding how safe the molding heads are? Looks like a lot od mass spinning around.
They are very safe and are no more dangerous than a dado set. Just don't expect great molding to come from them. You have to run the molding very slow to have usable molding but it will work. I've even used one on a radial arm saw with the arbor pointed straight down for cabinet door raised panels.
 

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where's my table saw?
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molding head in a RAS

As Steve said you can use it in a radial arm saw vertically oriented:

Making beads on the table saw:
 

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Ok so not really worth getting. Router bit is best
Yes and no. If you can get a router bit to do the work you want then a router is best. Now if you have to make a piece of molding to match an old molding you can't get a router bit for then the molding cutter is very valuable. You can take a blank knife and grind your own designs on. I used one for a long time until I bought a shaper and now do that kind of work with the shaper.
 

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I've been using one for years primarily for making molding and trim. I don't think they are any more dangerous than a dado.

In fact, there is a long and good article in the most recent ShopNotes about molding heads and how to use them.
 

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since most table saws turn at 3000-4500 rpm, and the moulder heads i've seen (craftsman) were 1 or 3 head, you're not getting a lot of cuts compared to a routers 22000 rpm. it does take a sloooow feed rate. for a nice cut.
 

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Tim, it's about the diameter

since most table saws turn at 3000-4500 rpm, and the moulder heads i've seen (craftsman) were 1 or 3 head, you're not getting a lot of cuts compared to a routers 22000 rpm. it does take a sloooow feed rate. for a nice cut.
The 22K RPMS are for 1/2" diameter cutters and under, more or less. You wouldn't run a 3" panel raiser at 22 K. So, when the diameter is 6", like a molding head running at 3400 RPMs, the peripheral tip speed is about the same. Obviously a 3 cutter head is better than a single, more cuts per revolution, but the finish and quality of the cut and the type of wood will let you know how fast or slow to feed it.

According to this link, the peripheral tip of a cutter has traveled 21 units of length per 1 revolution:
http://www.chacha.com/question/how-...when-you-know-the-rpm-and-radius-of-the-blade

Or 2IIr units of length per rev.
 

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I have a moulding head with a large selection of knives. I use it occasionally. For the most part use has been uneventful. I use feather boards to hold work against the fence as well as feather boards on an extended fence to hold the work against the table. There was one time that I was feeding a piece of oak through with a very small knot in it. It caught and actually broke a couple of fingers off one of the feather boards. No harm done except for the split second that my heart stopped.
 

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The 22K RPMS are for 1/2" diameter cutters and under, more or less. You wouldn't run a 3" panel raiser at 22 K. So, when the diameter is 6", like a molding head running at 3400 RPMs, the peripheral tip speed is about the same. Obviously a 3 cutter head is better than a single, more cuts per revolution, but the finish and quality of the cut and the type of wood will let you know how fast or slow to feed it.

According to this link, the peripheral tip of a cutter has traveled 21 units of length per 1 revolution:
http://www.chacha.com/question/how-...when-you-know-the-rpm-and-radius-of-the-blade

Or 2IIr units of length per rev.
of the three factors determining a quality cut (other than blade sharpness, etc) is cuts per revolution, feed rate, and diameter. my opinion is that diameter is the dead lowest factor. not the highest, i humbly disagree. you will see a more improved cut quality by using 3 cutters per head, or a slower feed rate, than a 6" head vs a 4" head.
 

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That wasn't what I was trying to get at

of the three factors determining a quality cut (other than blade sharpness, etc) is cuts per revolution, feed rate, and diameter. my opinion is that diameter is the dead lowest factor. not the highest, i humbly disagree. you will see a more improved cut quality by using 3 cutters per head, or a slower feed rate, than a 6" head vs a 4" head.
What I was getting at is a 4" head at 3400 RPM will have lower peripheral speed than a 6" head at 3400 RPMs all other things being equal, 3 cutters, sharpness, etc. So, in theory, the feed rate can be increased slightly using a 6" head.
We always run the smaller router cutters faster than the large diameter ones, so that the perpheral speed is similar for best cutting efficiency.



https://search.yahoo.com/search?ei=utf-8&fr=ytff1-gl-gen1&p=router%20speed%20chart&type=

 

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For normal flat work, there is only one type of cut that I can think of where a molding head does what a router cannot, that's reeding in the center of a wide board. I don't think the quality of the cut or ease of use is as good as a router for most other applications. Smaller saws, for which larger dadoes are not recommended, shouldn't be used with molding heads.
 

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All the details about the size of the cutterhead is really unimportant to the topic of this thread. TimPa brought up the speeds, and that would refer to just adjusting the feed rate and cut for the detail that's being run.

But doing math to figure out what size and what the peripheral speed is, is not necessary. Actually, I prefer to use a router whenever possible, and for some profiles I may use a cutterhead in the tablesaw. If it's a good subject for a shaper with a power feeder, I may use that. I've never had an occasion to have to figure tip speed on a cutting knife.

Back before there were variable speed routers, fixed speed routers were used even with large bits. It was just a matter of getting the feed rate, and depth of cut right to be safe and smooth, and that happened after trial and error and just plain experience.






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no less safe than a dado set

Im wonding how safe the molding heads are? Looks like a lot od mass spinning around.
The safest operation would have a special insert in the saw for the least amount of gap around the cutter head, not only fore and aft of th blade but on either side. I recently had a push stick slide off into a dado head and it shot back at my palm hard enough to break the Maple stick and pierce the flesh deeply. There was too large a gap at the start of the dado head AND I was using a stick a that was just "handy" not a dedicated push shoe.... :thumbdown:

Yes, there is a lot of mass spinning around also, but not as much as a full stack of 8" dado blades, which takes a few hours to stop spinning... :no:
The molding cutters I have are usually for edge profiling although they can be used on the face as well. To profile an edge using the table saw fence is also where you want as little gap as possible so the workpiece can't tip into the hole or catch on it as it enters.
You also want a good tall sacrificial fence if the whole cutter profile is not needed.

This is where a RAS with the cutter spinning horizontally behind a
enclosed guard and the workpiece laying flat on the table, would be a safer operation.... as in the first video I posted:
 
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