Rail/Stile Cutting Help Needed - Stumped

[Larry Fox]

I have run into a strange problem cutting matching rail and stile parts that I can't seem to sort out and could use some help with. What I am having trouble with is the gap in the picture below - I can't seem to sort out how to get rid of it as the shaper head I am using doesn't have any apparent way to adjust this particular aspect of the cut.

The particulars:

- Shaper: Grizzly 1026
- Cutters: Freud RS 1000 with the RS-B profile knives
- Spindle Size: 1"
- Adapters: Freud 1" to 1 1/4" adapters
- Spindle Runout (checked with dial indicator): ~2-3 thousandths at the top, almost none apparent near the bottom.
- Spindle orientation to table: using the ruler "trick" it appears to be within a thousandth or so of parallel to the table

I have checked and dialed up everything that I am aware of and none of it has appeared to make any difference (no better no worse). I have removed and reseated the inserts several times to no avail. The only adjustability available on the cutter-head is shims for adjusting the thickness of the tongue on the cope profile and as you can see in the picture, I think I have this pretty well dialed in.

Anyone ever experience this or know of a way to correct it. I am pretty frustrated at this point because this is really holding up this job and there is no way I am letting doors that exhibit this out of my shop. Not only is it unacceptable from an aesthetic perspective but it will create a weak glue joint.

Thanks in advance for your time.

200322

[Mike Heidrick]

Try new RS-B knives.

Then buy some Freeborn cutters.

[David Kumm]

Since the gap is at the top have you tried running the opposite direction and reversing top and bottom just to rule out the spindle? The runout could be worse when cutting pressure is applied. If you get the same gap with the cutters upside down it has to be the inserts not matching. Suspect you have to buy those in matched sets. Dave

[Dan Hahr]

Looks like you need to remove some shims from between the bearing and the profile cutter when cutting the rails. Not sure if that is exactly possible with your cutters, but that's what you'd do with a router bit. The shims need to be adjusted, one way or another.

Dan

[Tom Hintz]

Looks like you need to remove some shims from between the bearing and the profile cutter when cutting the rails. Not sure if that is exactly possible with your cutters, but that's what you'd do with a router bit. The shims need to be adjusted, one way or another.

Dan

+1 on removing a shim or two. You need to close the outer side of the joint down onto the inner (rail side) part. Been there, done that - more times than I want to admit before I figured out the shim thing!

[Jim Matthews]

Perhaps it's a foolish question; if you glue up a sample, can the gap still be found?

[Larry Fox]

Guys - thanks for the replies and the time. In order:

Mike: I might give new cutters a try but I want to talk to Freud before I go that route. I can't imagine Freeborn is the only company able to produce quality cutters.

Dave: I have not tried that but it might come to it. The cutters did come as a matched set.

Dan - there are no shims nor an apparent place for any. I will give another look though.

Tom - See response to Dan.

Jim - The joint you see is glued.

I am going to try a few more things today but I am running out of options and will call Freud to get their opinion tomorrow a I have already invested a ton of time in this.

[Chip Lindley]

Larry, my first thought is that perhaps when cutting the male/female parts, the stock is moving slightly during the cut. Use of a backer board and firmly clamping the coped stock to whatever fixture you are using to feed it squarely through the cutter may help. Feeding must be rock-solid to avoid any movement, especially on the cope cuts. When cutting the profile on the stiles, "snipe" must be avoided as the cutter exits the stock. If not supported fully, the cutter may have a tendency to push the stock away, causing a mismatch in the profiles.

Survey your methods of holding the stock when doing both cuts. Consider use of an outboard fence that holds the stock away from the cutter for consistency in profiling stiles. Pushing stiles against a split shaper fence is inherently bobble-prone.

Good luck finding where the problem lies!

~~Chip~~

[Don Jarvie]

Picking up on Chips theme is the gap all the way along the rail if you were to run the stile along the whole piece? If the middle is better than the ends you can work on your technique or make the pieces longer and cut off the ends where there is some play.

Don

[Larry Fox]

Chip and Don - thanks for the replies. I am going to follow up on your suggestions tonight and really start looking hard at my fencing, featherboarding, etc situation to rule it out. I think things are tight but at this point I am willing to look at anything. Don, to answer your specific question about any variability along the length it is quite consistent which leads me away from snipe or anything like that but you never know.

One thing that I am going to look harder at is the table insert to make sure that it is as close to flush with the table as I can get it. If it were proud at all I can see how it would contribute to something like this. If it were recessed I think it would be opposite.

I talked to Freud this morning and their first thought was the cutters might have been machined out of spec although the guy did say that they don't see it much and that it was a shot in the dark. He wants me to send them back with some samples so that they can have a look at them. Given that I am dead in the water with this project I ordered another set so I can see if that solves it. If it does, I will be back in business before the existing ones even make their way back to Freud and I won't have to waste their time. If not, I have pretty much ruled that out. Inserts were $50 with expedited next day shipping so the experiment is cheap relative to the time I have wasted thus far.

One thing the Freud guy did confirm for me was that there is no shimming available for this part of the cut so, looking on the bright side, I suppose that is a bit of positive news. One variable eliminated. :)

[Larry Fox]

Update on this for anyone following along at home. I ordered another set of inserts and installed them over the weekend - same problem to exactly the same degree so I have either ruled out the knives or received two bad sets. The later seems extremely unlikely so I am going with the principle of parsimony and ruling that out.

I have turned my attention to the shaper spindle not being perpendicular to the table. I had adjusted it to (what I thought) was the best of my ability using the ruler "trick" but wanted to verify that things were dialed in. So. I spent several frustrating hours on Saturday hunched over the shaper with a dial indicator trying to get it dialed in better. I was able to get it to within about .004" front to back indexing from the same surface on the top of the cutter-head but it was a hit or miss process. I then switched over to using a torque wrench to make sure all the bolts were tightened the same and was able to dial it down to about .003" front to back. the cut got better but still not acceptable.

Question - do I really need to dial this down to .000" in order to get a good cut or should I be looking at something else?

My shim stock also leaves something to be desired so I have ordered some shimming washers from Mcmaster that should be in on Wed. I will see what I can do with these but this seems to be a lot to get a good cut.

Amazingly frustrating experience I can tell you that. Thanks for the time to read my rant. :)

[Don Jarvie]

Do you have other knives that you can put on and see if you continue to get the same type of problem? If the shaper is off it should show up on any set of knives.

Have you tried to glue up a door and see what it looks like when its done? Maybe when the door is glued up, sanded and finished you won't even notice it. Maybe worth a shot.

The average person wouldn't notice this at all. We do because were much harder on ourselves than any client would be.

Don

[Mike Schuch]

I have an old Walker Turner shaper. I have to lay it down on it's front to adjust it. When I set it back up right the weight of the motor pulls it out of alignment. It took forever to get it tweaked to perfect but it has stayed that way for many years of use. There is a smidgen of play between when the spindle height lock is tight and loose for adjustment. So I always run it locked and get perfect 45 lock miters out of it every time.

Your problem definitely looks like a spindle alignment issue to me. I don't no how good is good enough for alignment. I always use a long metal bar clamped between the shaper nuts to mount the dial indicator to.

[Chip Lindley]

Larry, the only other variable I can think of that you have not determined, is any runout in the spindle under load. With the spindle loaded with a cutter under power, any play in the bearing seat of the quill will cause wobble and vibration in the cutterhead at 7K or 10K RPMs.

With the machine off and unpluged, place a dial indicator against the spindle. Grab the spindle at the top and try to pull and push it side to side toward the four sides of the table. Also indicate on top of the spindle and see if there is any vertical movement when you pull/push up and down.

After hours of use, the hardened outside race of especially the top bearing can wear the seat in the cast iron quill. Any variation must be shimmed to zero and LocTited in place. Might as well spring for new spindle bearings while you have the quill out. We know Grizzly does not use overly-expensive bearings in this high-speed shaper.

I did this same procedure to a well-worn Powermatic #26 shaper and made it run good as new again.

~~Chip~~

[Jeff Duncan]

Not sure where your problem is, but I can tell you that you do not have to get to .ooo to get a good fit. My shaper is tuned to +/- .002 and parts fit together correctly.

You say your using insert cutters, is the profile cut by a single knife as opposed to stacking several cutters? If so I can't see the cutter being the problem, and I can't see how you could shim it unless I'm missing something? At that point I would start to suspect the machine. If your bearings are going your cuts will get progressively worse. Not sure whether or not this would be evident at a stop, (I couldn't detect any play on my PM27 when the bearings went) I can tell you the cut quality got bad fairly quickly.

Lastly you say the cut has gotten better....how much better? The original pic was a bit sloppy on the profile, but certainly not out by a ballpark. How close is it now and how tight are you trying to get?

JeffD

[Nick Canzona]

Looks to me like you might be pressing down on the female part a bit too hard as it contacts the cutter.

[Wes Grass]

Not much in the way of details in Freud's catalog, so I'm just guessing as to how this thing goes together. Assuming the grooving inserts tuck up into a pocket underneath the -R cutter head. And assuming you've checked that the inserts track each other and there isn't a burr on the cutter head or stop plates.

You need to lower the groovers in relation to the profile. Probably not a good idea to try shimming the groovers down, but you could shim the stop plates for the profile cutters up to let them sit up higher.

And seeing the same results with 2 sets of inserts leaves the possibility your cutter head is machined wrong.

Oh, and why are computers so stupid that after you've downloaded a pdf like this, and then decide you want to save it, it has to download the damn thing again? It's in memory, isn't it? Can't it just be written to disc from there?

[Larry Fox]

Guys - thanks for all the time for the replies and apologies for letting them go unacknowledged for so long. In order:

Don - I have acquired another set of knives and it exhibits the same symptoms, no better, no worse. I also (unintentionally) lucked into another brand new head that I can try so I will give that a whirl and rule that out. I think I agree with you that it is some sort of alignment issue - likely the spindle to the table. I got a bunch of measured shim washers from McMaster and will install those to see if I can sort it out. As to the joint, the joint you see in the pic is glued. While I think the joint is "fixable" from a visual standpoint I have concerns about the integrity of the joint if they don't meet perfectly. The cope end is end grain which is an inherently week joint under the best of circumstances.

Mike - fortunately I don't need to turn this one on it's side but the front two bolts are tough to get to which makes adjustment seem imprecise. I hope the washers I mention above help with this.

Chip - I will give your suggestions a try to rule it out (or in) but this is a new shaper so I have thus far been leaning away from the bearings. Worth a look though.

Jeff - I hope I don't need to get it to .000 :). Profile cut by a single knife and no way to shim it. By better I mean the gap has reduced a smidge - not enough to call it good. I am trying to get to a perfect match as I have been able to achieve fairly easily via other means. I have gotten much better and more consistent results off a router table in the past. It seems that I should be able to at least match that performance.

Nick - I have looked at the feed for both parts. For the stick portion I am using a power feeder with about 1/4" of pressure. I am using a sled riding in the miter slot for the cope but am trying to come up with a way to jig the cope cut to use the power feeder.

Wes - You pretty much have the right idea as to how they fit together. The knives seem clean and well machined. The manufacturer makes no provisions for shimming the knives or groovers so I am really not willing to do that lest something disastrous happen and one of them come off. I have another cutter head that I am going to try. I can't help you much with the PDF thing - it does not make much sense to me either.

Thanks again guys - I am really holding out a lot of hope in being able to dial the spindle in tighter and it fixing it. On the positive side, at the end of all this I will have one well tuned shaper and one that I know very very well. :)

[Jeff Duncan]

The amount of pressure on your sticking/coping cuts won't help or hurt at all. The only thing that would affect is the faces of the parts being in the same plane, the profile is the same regardless of how much pressure is exerted, as long as it stays constant. I wouldn't bother with a feeder for the cope cuts. It will only make the process slower and much more cumbersome.

I think I'd be tempted to put a call out and see if I could find someone local with a shaper, (ideally a better quality one), that would be willing to let you run a few parts with your cutters installed. It would be great if you could at least rule out the head itself completely.

good luck,
JeffD

[J.R. Rutter]

In my experience, bushing cutters to fit smaller spindles can be a finicky process, even with well machined bushings. If the cope cutter is sitting at a tiny angle due to burrs, dents, grit, etc. on the faces of the bushings, it will give a wider cut and sloppier fit. Even invisible tolerance issues in the bushings and cutterhead can add up. I would remove and reinstall the bushings, rotating them in relation to one another.

[Carl Beckett]

Some thoughts:

Looking at the picture it seems that the 'tongue and groove' part of that joint is tight. (The square portion of the profile). It seems to me that if there was runout or spindle out of square, et al - it would impact both portions of the joint.

This means that since these come pre-assembled from the factory, and without shims for adjusting, then it HAS to be a factory tolerance error.

It seems the only way to resolve this would be to take the bit apart and run it in two passes - one for the slot, and then the ogee - which pretty much defeats the purpose of matched set to begin with.

I cant tell exactly how the cutter pieces might stack to create the profile, but my gut says that one would have to be GROUND at the interface to the slot portion, so that the ogee removes less material thickness. And its looking like a good 0.010" would be needed.

So my $.02 - I wouldnt be chasing runout - it seems like an inherent mismatch between the bits. Maybe those shims can be moved to a different side/location and shift the relative position of the ogee portions?

[Larry Fox]

Guys - thanks very much for all the replies and the great information. I spent a few more frustrating hours tweeking and tuning - nothing. I setup for another run of scrap this time measuring things with the dial indicator as I completed steps. Nothing was out more then .001 and the mating surfaces (such as busings etc) were all spot on. I ran the scrap paying attention to holding pressure etc - same result. I then ripped the tongue off the coped end of a sample just to see how far the profiles were off. They matched perfectly when the tongue was missing but not with it there. This led me to sit down and stare at the joint for a good 10 minutes trying to sort out what I could change to adjust for it. I concluded that the tongue needed to be lowered. The groover cutters come off and Freud directs you to take them off when doing the cope cuts so as to not mar the bottom side. I have an old Somerfield rail and stile set for the router lying around and they came with very thin shims. I took two of those and put one under each of the groovers and replaced them. Perfect fit!!!

Now, there is absolutely no mention of this in ANY of the Freud material I looked at so I think I am a bit off the reservation here but the bottom line is that it worked exactly as it should have originally. My job should be back on track.

Thanks once again for all the time spent on reading and replying.

On the bright side, my shaper is tweeked and tuned to be a precision instrument at this point and I know pretty much every nook and cranny of it. :)

[David Nelson1]

I can't wrap my head around the cure Larry. Would you mind posting a few pics?

[Larry Fox]

David, I will when my wife returns with the camera, she is out of town for a few days.

[David Nelson1]

Very good sir. It sound like the shim came from a whole set of tooling?