Shaper snipe troubleshoot

[Mike Tagge]

I’ve been working on some cabinet door parts and putting them through my power feed on the shaper along with the Aigner 4 wheel device. I have the outfeed fence parallel to the deepest cut on the cutter and indeed set to take off about .5mm. I consistently get a big snipe at the leading edge of the piece especially for the shorter pieces, say 250mm and less, and sometimes one on the trailing end. Long pieces seem to go through ok. How can I figure this out? I like to do the tennis first then cut the rails to avoid blowout on the cope. But I’m wondering if this might not be possible for shorter pieces.

Thanks,

Mike

[peter gagliardi]

Your outfeed fence is set proud of your cutter diameter.

[Patrick Walsh]

What Peter said,

Cope first then take all your rails, reference them all in a line against say a long jointer fence with up side up or down however you ran your cope. Cut a piece of 1/4” mdf just under the width of your parts and close to the same light of them all ganged together like a train. Use double sided tape to stick the mdf to the rail now run as one big stick.

But first do as Peter said.

You can also make a sacrificial fence that spans the infeed and out feed fence. Sometimes it’s also the powerfeeder applying pressure just the wrong way.

[Martin Wasner]

Stick first, cope second.

[Patrick Walsh]

How do you cope second and not get blow out on opposite apposition sides of your copes?

You must know something I don’t as I can’t get clean cuts any other way than to cope first then stick as the stick cleans up any blow out form the cope.

Stick first, cope second.

[Martin Wasner]

How do you cope second and not get blow out on opposite apposition sides of your copes?

You must know something I don’t as I can’t get clean cuts any other way than to cope first then stick as the stick cleans up any blow out form the cope.

You need a backer. Square shaker style you can use the same backer, since it's square. With a profile, you need to take the coping head and treat it like a sticking cutter and run a piece to be the backer for the profiled edge. Sometimes, depending on how well the knives are set and the run out of the spindle you'll want to run it twice with just a twinge of height difference to create some slop. You want the profiled backer to fit snug, but not so tight you can't get the rail free from it easily. You can't just throw the backer in there either, You gotta grip it in the fixture. Any gap will allow blow out. We also remove a 1/16" of length when coping to remove any fuzz from being cut on a saw blade. Rails are cut 1/8" long to account for that.


I did it that way for years. Still do it that way often for shorter pieces that are have a double sticking cut. Longer pieces that I don't have to worry about the power feed being able to hang onto it I'll cope first then stick just because it's easier.


If I have a shaper and a dust collector running, it should be cutting. That's the main reason I do full length sticking cuts. I can run parts nose to tail and have almost zero open machine time. I might've told you this in a pm, there was a dude on instagram showing a video of himself running long parts through a shaper. A professional mind you. No infeed, no outfeed. 30 second video. That machine sat empty for half of it while he was either loading or unloading. I told him he could double his productivity and halve his operating cost be running them nose to tail. Manufacturing has only two modes of operation with zero grey area. You are either producing or consuming. There's gradients of the two modes, but nothing in between. If I were to run 100 fronts worth of parts individually, there's no way I could keep that thing cutting. Plus it gets sketchy with small parts going through a feeder. You tend to run those with enough space between them that the feeder is relaxed and the previous part is clear before running the next. That's a lot of time consuming and not producing.


Or, the way I do it now is left and right copers. One counter clockwise, one clockwise. Both face down since the sticking cut is made face down. Then you just need a square backer for typical door parts that way. Due to folks never checking things.... we had some cumulative errors on a run of 74 fronts so all of them got canned. I ripped, jointed (which I rarely do, but I don't play around when dealing with a SNAFU), re-ripped, sticked, sized, cut to length and coped all those parts in about 5-1/2 hours. I was pushing pretty hard, but only had one blow out of any consequence doing almost 300 copes. Our doors are made .040" oversized to allow for edge sanding. A little speck of blowout isn't a big deal since it will be removed in the edge sanding.


I like the PMK coper. Two heads. You put your parts in flat to flat so one acts as the backer for the other. The table cycles a bit one way dipping into the part, then finishes the cut with the other head. Pneumatic clamps hold in two directions, the parts tight to the table, and tight to one another.


Most people cope way too slowly too. You need a constant feed rate, and to be fairly aggressive with it. Being too slow just gives time for things to wrong and end grain can be cut way faster than long grain if everything is right.


The fixture for coping has a lot to do with it as well. We use the Reliable clamp, it's okay, but there's room for improvement. I'd like to see it mounted on linear bearings, I just haven't bothered putting something together like that. But the backer has to be TIGHT to the workpiece. Anything else will result in failure.


Sorry, I think about doors and process a lot. Almost certainly the main reason I don't sleep.

[Patrick Walsh]

Jesus,

You do think a lot, maybe more than me lol..

The idea of marking abacker with the profile is so simple but something I never thought of. It getting stuck could be a royal pita but I’ll give that a try on our next project.

Our next project the doors are going to be a royal pita anyway. They are a door in a door. Think a quartered white oak 5/8 mitered five piece door captured In a slot by a 1” shaker style door with a applied Scottie. We have been going back and forth trying to decide the most efficient way to produce these doors along with assure the mothers stay together.

So far I like a mitered bridal joint cut on the shaper. The boss like my idea to edge taping a bunch of mdf core for the mitered portion.using that for the miter. So we would build a 1” shaker door cut out for glass. Drop in a 1/4 mdf core panel. Apply the mitered detail they apply the scotia over it.

Either way assuring the work is good enough it does not blow apart over time, no glue squeeze out incurs and the sanding is up to snuff to not create problems with finishing should make the whole ordeal a real time consuming affair.

To boot I bet we need like 100-150 doors and df likes this.

[Kevin Jenness]

I used to cope first, but when I went to one shaper due to space constraints I started sticking long pieces first, which is more efficient, and coping second. As Martin says, the backer has to be a good fit but not so tight that you can't get the rail out easily. I get the best results with a fresh backer for each cut, so I make 6 or 8 backer pieces, use them once then cut the batch shorter and repeat. I clamp the backer and workpiece both vertically and horizontally- a loose backer getting sucked into the cutterhead is not something you want to experience.

As far as snipe goes, an outboard fence eliminates the problem, especially for short pieces. If the pieces are too short to span the feeder wheel spacing then Patrick's suggestion is a good one, but if you are sticking first it won't be an issue.

[Patrick Walsh]

Kevin that sound slow!

I can’t imagine switching out a backer board for every cut on a whole kitchen. I do that when makeing tenon for furniture pieces but that’s kinda slow work by comparison so it doesn’t feel like a huge time loss as your more concerned with finished product. For door parts though I want to be able to run a whole kitchen in minutes not hours.

But your solution is a solution for someone looking to just get it right if they are struggling.

I used to cope first, but when I went to one shaper due to space constraints I started sticking long pieces first, which is more efficient, and coping second. As Martin says, the backer has to be a good fit but not so tight that you can't get the rail out easily. I get the best results with a fresh backer for each cut, so I make 6 or 8 backer pieces, use them once then cut the batch shorter and repeat. I clamp the backer and workpiece both vertically and horizontally- a loose backer getting sucked into the cutterhead is not something you want to experience.

As far as snipe goes, an outboard fence eliminates the problem, especially for short pieces. If the pieces are too short to span the feeder wheel spacing then Patrick's suggestion is a good one, but if you are sticking first it won't be an issue.

[Kevin Jenness]

Patrick,

It is slower, but the cut is consistently clean. I want clean joints whether I am making one table or fifty doors, and I know I can get that using a fresh backer. For the same reason, when I crosscut panels on the slider I keep a stick at hand to back up each cut so I don't get chip-out on the trailing corners. If you get an acceptable result reusing the backer, good on you. With sharp tooling it usually does fine, and you can toss out the occasional faulty piece.

I don't feel like I am struggling, but I am "looking to just get it right." If I spend an extra hour on a batch of doors and don't see even minor blow-out in the corners when assembled I'm happy. I am working for myself so I get to decide how much time I spend to get the results I want. I am saving time over my old way by not sticking the rails individually. To each his own.

[Martin Wasner]

Kevin, that's where removing some length of the rail in the coping cut helps. Your backer never erodes from chips hitting it over and over again. It's constantly being freshened up.


I also back cut the backer so it almost comes to a point on the trailing edge of the cut when fresh. Eventually it ends up gone, that's when we swap for a fresh one. We always have an excess of 1-1/4" wide material, so that is the first thing I go to for making backers. I grab a bunch of sticks or scraps left over from frame material and cut them to 18" since it's a comfortable length. They start getting short, they just get pitched.


Ideally your backer is just a freckle thinner than the stock your machining to ensure it stays put.


Yes, sucking a backer into a shaper is annoying. Usually ends with a fence being out of place, and shattered carbide.

[Mel Fulks]

I get all the rail material 5 and 1/2 wide or more and cope using the "rub collar" . Then rip to width before running profile .
If a rub collar did not come with the set they can be bought separately . Rails that are too short to profile without snipe are lined up
and get a piece of plywood stapled to the backs to avoid any snipe.

[Jeff Duncan]

Some good points already. I'll just go through my method, (which I think is very similar to what Martin has mentioned), for the heck of it. Run all sticking parts first and run using an outboard fence. You'll never futz around wasting time setting your shaper fences again once you start using an outboard fence, and your stock is on the money every time. And as has been mentioned is more efficient for larger jobs as you can run extra and cope as needed.

For copes I use a second shaper with a sled. I also use a backer piece as mentioned but I make use of 2 toggle clamps on my sled. One holds the backer and one holds the rail. This way if I need fresh backer I just pop the toggle and move the piece forward slightly. I have it set so that when the stock on my sled is pushed up tight to the shaper fence the cutter will remove the profile + 1/32". This accomplishes a couple things, first I know I'm always getting a full cut. Second I know that all my parts are cut exactly 1/16" oversize before coping.... making for easy math. Plus this way whenever I want a fresh backer I can have it just by advancing it that 1/32" that gets removed at every pass.

I've tried other methods like running parts against the shaper fences, using rub collars, stacking cutters etc etc. and this is the method that i've found makes the most sense for me. I won't say its the best for everyone as scale, equipment and other factors certainly come into play. But it works well, is repeatable, and provides a really highly quality of joint.

good luck,
JeffD

[Patrick Walsh]

This is exactly what we do except for the sticks with a outboard fence. I really want to get setup with the outboard fence and climbcutting. I tried the climb cut when making the df passage doors taking a tiny bite for the .75: panel groove and it was a mess. Basically all burn marks and my spindle came to a near stop. That was the end of that but I was also using a 4hp machine. I figured it was a tiny bite so?

Anyway the oversized of the rail by 1/16 then setting up outfeed fence to take a 32nd is how I have been taught. Now the extra toggle clamp for the backer board is something I’m gonna have to rig up. We use a old t110 with the bolt on slifding table that has the manual clamp. To f]date we screw our back on. It makes it a real pita to move on the fly. Hmm how am I gonna mount a toggle to the darn thing now.

I really really like the idea of being able to move your backer lickidy split when cuts start getting sloppy. We use this bevel profile quite a bit lately and it leaves the thinnest little whisper of wood at the edge of the cope and no matter what we do it’s always like the cutters are dull. This results in sitting there with a tiny square block wrapped with sticky back sand paper and cleaning every single one.

Some good points already. I'll just go through my method, (which I think is very similar to what Martin has mentioned), for the heck of it. Run all sticking parts first and run using an outboard fence. You'll never futz around wasting time setting your shaper fences again once you start using an outboard fence, and your stock is on the money every time. And as has been mentioned is more efficient for larger jobs as you can run extra and cope as needed.

For copes I use a second shaper with a sled. I also use a backer piece as mentioned but I make use of 2 toggle clamps on my sled. One holds the backer and one holds the rail. This way if I need fresh backer I just pop the toggle and move the piece forward slightly. I have it set so that when the stock on my sled is pushed up tight to the shaper fence the cutter will remove the profile + 1/32". This accomplishes a couple things, first I know I'm always getting a full cut. Second I know that all my parts are cut exactly 1/16" oversize before coping.... making for easy math. Plus this way whenever I want a fresh backer I can have it just by advancing it that 1/32" that gets removed at every pass.

I've tried other methods like running parts against the shaper fences, using rub collars, stacking cutters etc etc. and this is the method that i've found makes the most sense for me. I won't say its the best for everyone as scale, equipment and other factors certainly come into play. But it works well, is repeatable, and provides a really highly quality of joint.

good luck,
JeffD

[Martin Wasner]

I really want to get setup with the outboard fence and climbcutting.

With good heads and sharp knives, you should not have to climb cut. A power cut has a higher chance of tear out obviously, but it's not as fuzzy. Just cut around any tear out.

There's no decent way to collect that I've found either.

I used to climb cut a lot of stuff, but since getting better shapers and really good heads, I haven't even considered it.