panel raising with back cutters on shaper?

[Brian White]

I have a few questions about panel raising with back cutters do you prefer to run panels with the profile of panel up or with the face of the panel down leaving the back cutter on the top of the spindle? Got any pictures of shop built fences you are using to do your panel raising?

[Karl Brogger]

I've never seen a panel run through a shaper face down. At least not for the traditionally sized scoop or variants. I don't think too many shapers have a large enough throat to allow for the huge diameter of most panel raising cutters.

[Paul Atkins]

We used to do that all the time. We were using a power feeder so finger in the way was not the issue. Don't remember why otherwise though.

[Rod Sheridan]

I was taught to use the cutter under the work piece whenever possible for a few reasons;

- it references off the front of the panel so any thickness variations occur on the reverse side

- the work piece helps act as a guard

- there isn't any risk of having the workpiece become trapped between the cutter and the table.

If I remember correctly my panel raising cutter is about 5 1/2" in diameter and my shaper has a table opening of about 7".

Regards, Rod.

[David DeCristoforo]

The "advantage" of running face down is to prevent the material from getting ****ed by the cutter if, for any reason, it (the material) is lifted slightly. But with a back cutter, this becomes "moot" since you have a cutter on the top as well as the bottom of the stack. As Karl pointed out, you need a pretty big opening to submerge a panel raising cutter. If you are using a feeder, the stock getting lifted into the cutter is not much of an issue. The thing is, if you use a feeder for panel raising, you need a lot of HP because you are taking a big bite, esp. with a back panel cutter in the mix. Most feeders cannot be run at a slow enough feed rate to allow a full panel/back panel cut on a shaper with anything less than five+ HP.

[Paul Atkins]

We always took 2 passes as I remember. One roughing cut and a final cut.

[Erik Christensen]

a quick question. i was watching a video on youtube of a panel raiser on a shaper with a power feeder. it was obviously a commercial shop as the guy had it down cold pushing raw panels into the power feeder. what he did was put a 1st pass about an inch or so away from the fence - took the panel out and ran a second time against the fence to do it in 2 passes. from the size of the machine i thought it could have been done it in a single pass so I assumed his methind was for finish cut quality.

wouldn't such a technique work for those with <5hp shapers who wanted to do panel raising with a power feeder?

[Chip Lindley]

Erik, a 5hp shaper has the power to raise panels in one pass (even with back cutter) but two passes make for a cleaner quality finish!

I've raised lots of panels (1-1/4" bore Freeborn, Freud, Stehle w/ backcutter) on a 3hp shaper, making 2 passes. Always face up. I've had excellent results. Straight-edge panels can be fed through all day with a PF, but the armstrong method taxes a guys nerves! An aux. fence is set to hog off all but a light finishing cut, then removed to finish off the final 1/16" or so.

Pretty much out of vogue now, I raised lots of cathedral panels without the aid of a PF! The top edge of arched panels was fed by hand in a holding jig. Although hold downs kept the panel from lifting, it had to be pushed tight against the rub bearing while feeding it right to left. Intense!

[J.R. Rutter]

Here is the type of fence that I used to use for doing this cut. There are spacers outside the frame of this pic to register the fence against the table. The top edge of the fence does not have the spacers. It flipped to do traditional panels where only the top was raised and the back was flat. The basic idea is to support the panel edge the whole way through the cut. Two passes works well with the feeder without worrying about moving the fence.

http://lh4.ggpht.com/_7ftZyQvHxr8/S6AV1AzjkWI/AAAAAAAAAOY/5mJJoRuZ25E/s640/DSCF0002.jpg

http://lh4.ggpht.com/_7ftZyQvHxr8/S6AWRtZJAdI/AAAAAAAAAOc/fupHzdID5nY/s640/DSCF0003.jpg

[Randy Henry]

J.R.,
Is the purpose of this to keep the corner of the panel from tipping into the opening ? This looks like a pretty good way of preventing this. I have had several tip into the wideopening. This may be the answer. Thanks.

R. Henry

[Peter Quinn]

Brian, I prefer to run the panels A face up with the panel raiser above, and most shaper panel raisers are designed to run above the work in traditional rotation (CCW when fed from right to left). I prefer not to run reverse rotation with a big cutter when possible, call it superstition, I don't trust the lock rings.

You can get cutters for either from some manufacturers, but many only offer the above the work format in CCW rotation. I was taught that the cutter should be above the work for making any tongue that must be precise. It eliminates the effects from any minor stock thickness variations and produces the most consistent tongue thickness. The table to cutter distance is a constant assuming the work is held firm to the table with a feeder. For a cut with a back cutter the accuracy thing is irrelevant, but I still prefer the panel raiser above. I actually prefer to run them in two separate operations, the panel profile first, the back cut second, both from above, unless I'm in a big rush.

Its really your choice though. Regardless of the size of hole in your table, you can run face up or down. If the hole is too small, run a 3/4" bed board with a radius slightly larger than the cutter cut out in front of the fence. Works well. In reverse rotation make sure to use that lock ring if your shaper requires one.

For a hood I'm using the one out of Lonnie Bird's shaper book. It works great, offers good chip collection, and considerable protection for your hands. I use a feeder in all circumstances. I think JR's continuous fence set up is a better method, the Bird fence and hood is a close second that has only a 1 1/2" opening. The smaller the opening the better, especially for narrow panels.

Erik, I've seen that same video. We did an arch top job a while back and did that exact thing, it worked great. We ran a fairly subtle angle on the feeder and took two to three light passes. We were starting off a reverse curved starting board and using a template on a rub collar, but the idea is the same. I've tried the same thing at home on my little 3HP delta, but frankly the results were pretty much the same as a single pass right off the fence.

Co-matic and Maggi both make a lower speed range gear set for their feeders that will let you hit a feed speed appropriate for raised panels. Costs about $45. Check with your feeder dealer. I bought a set for my grizzly feeder, gives you that "granny gear" that's almost too slow.

[Karl Brogger]

Some of the feeders can be slowed down by changing the gears, other than the shifter obiviously. In the case of the Delta feeder that I have it was just a matter of taking a cover off and swapping them around. I don't know what the speed is now, but it should be accompanied by a sticker that shows the turtle with a walker.

With a three wing insert head and making the cut in one pass it is very nice. One out of maybe 30-40 will blowout and have to have a chunk glued on.

(edit)- Peter brings up an extremely valid point about running large cutters in reverse. Chances are unless you have almost no threads holding it wouldn't amount to anything, but....

[Brian White]

Thanks for the pictures JR, (and to the others that responded), that is sort of what I was thinking about doing sort of a modified Bryd version .I have some narrow panels to make and I am worried about tipping into the opening But I think Peter may have the idea that suits me better by just using the "byrd style hood" that I have and doing it in two operations

[Glen Butler]

Most feeders cannot be run at a slow enough feed rate to allow a full panel/back panel cut on a shaper with anything less than five+ HP.

Not sure what you mean by slow feed rate, but I have successfully run raised panels with a back cutter on a 3HP PM25A and a PF41 power feeder at 13 FPM. It is evident that this is about the limit of what the machine can handle, but it did do it nonetheless. As I been told by my tool dealer, not all machines are created equal and gearing or other factors may create the need for more HP, though. Whether or not this is true may mearly have been his salesmanship coming through when recommending the 25A to me.

[J.R. Rutter]

I use a helper jig for feeding narrow panel ends. It is an approx 6" square the same thickness as the panel, with a strip of 1/4" plywood glued to the top and hanging off one side about 3-4". The panel to be shaped slips under the overhang and both are fed through the shaper, panel first, jig second. The jig keeps the panel from twisting and the strip of plywood is pressed very tight by the feeder. Sorry no pics here at home.

[Peter Quinn]

I use a helper jig for feeding narrow panel ends. It is an approx 6" square the same thickness as the panel, with a strip of 1/4" plywood glued to the top and hanging off one side about 3-4". The panel to be shaped slips under the overhang and both are fed through the shaper, panel first, jig second. The jig keeps the panel from twisting and the strip of plywood is pressed very tight by the feeder. Sorry no pics here at home.

Never thought of that for panels JR. we do something similar for other cuts, sometimes ganged by twos or threes We have also actually glued two or three narrow panels together real quick, and connected them with turners tape and strips of 1/8" masonite. I like your carriage idea best though.

When I mentioned gears, I wasn't talking about switching the two stock gears to change speeds. The manufacturers make and sell a set of two gears that offers a 4 speed feeder a lower range, essentially four more options. It works great for my 3HP delta, not so important on the 5HP minimax iI'm finding.

[J.R. Rutter]

I've mentioned this helper jig a couple of times, but never took a picture. Here is one that was on the shaper this morning. Someone has even glued sandpaper to the hold-down part.
http://lh5.ggpht.com/_7ftZyQvHxr8/S6ERAPo353I/AAAAAAAAAO8/RaosGjmK40w/s640/IMG_0575.JPG
http://lh3.ggpht.com/_7ftZyQvHxr8/S6ERAkxXi_I/AAAAAAAAAPA/QIf2rXcQsPc/s640/IMG_0576.JPG
http://lh6.ggpht.com/_7ftZyQvHxr8/S6ERBVHblLI/AAAAAAAAAPE/mTzhUrNaLOo/s640/IMG_0577.JPG