I need advice on pattern routing

[Greg Urwiller]

I'm trying to make some pew ends to use up the seat/back pcs I had left over from shortening one up. I had the local cabinet shop glue up some 1 1/2" red oak for the ends. I cut out a pattern from 1/2" ply figuring on using it to rout the final form. I'm really having trouble with the end grain grabbing bad on this. I've realized that I have to bandsaw closer to the line so I'm just skim routing more. I was using an old B&D bench top direct drive router table that I've had for years. I built it in to a cabinet so it was more stable and had a large table for more control. I had a 1/2'' shank router bit in it. It caught the top end of the pew end and blew the rounded portion in half. I can glue it together (I think!) but I'll still have to rout around it. Anyway, the old direct drive unit is howling pretty good so I think it's toast. No big loss. So, would I be better off using the router, or should I try to set up a cutter set on my shaper? Can I control a router on 1 1/2" oak? The pattern bit is 1 1/2" long so I'm trying to cut the whole thing at once. If I use the shaper I'll have to locate and buy the cutter setup. Or, am I better off forgetting the pattern routing and just bandsaw and sand, and sand, and sand, and......? Thanks. Greg

[Mel Fulks]

Rather than buying something just for this job, I would band saw within 1/16 of line and rely on running the router around backwards . Hold on tight!

[Myk Rian]

If you're using a pattern, do what you can with one grain direction, then put the pattern on the other side of the oak. The bit will be turning in the correct direction for the grain.

[Mel Fulks]

Yeah . But it's hard to register the pattern accurately on both sides without drilling holes all the way through and some grain spots that seem neutral might not be . With close sawing and sharp bit I don't see any disadvantage to using a lot of climb cutting and I have not encountered any. There might be some CYA warning from mfg. But I think most use router routinely and intuitively in both directions.

[Myk Rian]

You register the pattern off what was already done. A few pencil marks help.

[glenn bradley]

The grabbing is common when routing 'uphill'. I use bits with bearings on top and bottom for just this reason. The limit becomes the bit's cutting height so sometimes you have to have a template for top and bottom or (always an opportunity for flaws) move the template from one surface to the other. Double stick tape the template to the blank that has been bandsawn to within 1/16" of the final dimension. Rout downhill to the endgrain area. Flip blank/template and adjust the bit to ride the other bearing and again route downhill to the endgrain area.

277255

Another fix is to template route all but the trouble areas. Gang clamp all nearly completed blanks together and rasp/sand the troubled areas into form. The form may not be as precise as template routing but, they will all be the same.

[Loren Woirhaye]

I have an overarm router I use to cut out parts and my rule of thumb is to take off no more than 3/4" at a pass. I have routed patterns in thicker stock using pattern bits on the router table, but doing it in one pass is often problematic. Use a shank-bearing pattern bit to route one side, flip the piece over and use a 1" flush trim bit with a bearing on the end to do the other side.

[Mel Fulks]

Greg is the only one here who has seen the template or will see the stock. "Some grain spots that seem neutral ,might not be" Its just so difficult to find and glue those small pieces back on.

[Rich Engelhardt]

Its just so difficult to find and glue those small pieces back on.Piece of wood or pieces of fingers?
Or both?
;)

:D

[pat warner]

There is always an increment of thickness to waste where the stock won't tear out.
It may be only a 1/16" - 1/8th but it exists.
A plunger with a collar and straight cutter will do it.
I like WMC's 1079; it's 2" long so you can rout from one side with one templet.
A messy portable rout, alright, but safe. and without tear out.

[Mel Fulks]

That's a fair question,Rich. I've never seen anyone cut a finger with two hands on the handles....well,there was that one guy we had who used to work in a carnival side show. But he wasn't hurt so badly he couldn't get his old job back.

[Mike Wilkins]

The recent issue of Fine Woodworking magazine has a write-up on choosing and using pattern router bits. Great info there and methods of dealing with the change of direction of edge grain. Get yourself a copy and learn from an experts' advice.

[Mel Fulks]

Mike,that's interesting and I will read it ... In the library . They have given some real dumbbell advise on planer tearout over the years and turned down some good advise, and I have my letter and rejection letter to prove it. And some references who will verify that my suggestions work.

[Jeff Duncan]

OK my first answer is if your going to be doing more pattern work in the future than YES, by all means you want to do it on a shaper. A cheap shaper is still better than the best router. I'd recommend using a carbide insert head with bearing.

If your going to stick with the router than bandsaw as close as possible to the line. I wouldn't want more than say 1/16" of "meat" left to remove. Then get yourself a spiral pattern bit. They're more expensive than the straight cutters, but they are less prone to blowing out stock as your experienced.

Lastly….I was unlucky enough to find out that yes, you can indeed cut a finger, (well thumb to be more specific), on a router even holding on to it with both hands:(

JeffD

[Mel Fulks]

Jeff,......I didn't know. Sorry,... I'll keep you in mind as someone who Is good when an "extra hand " is needed....

[Stephen Cherry]

A cheap shaper is still better than the best router.



Sometimes the truth hurts.

For pattern routing, I only use the spiral bits. In my opinion, they are that much better. And I don't hesitate to "paper glue" a pattern onto the lumber. (glue paper to lumber, then pattern to paper- separate when done)

Also, I'm a big believer in the pin router. Even an el cheapo pin is going to allow you to gradually increase the cut height while maintaining the pattern position.

http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/daisypin.html

[Rick Potter]

Last night I saw info on the MLCS router bit website, about how to do this by routing part normally, and part backwards. They even had a short video.

Hope this helps.

Rick Potter

[Mel Fulks]

Greg ,know what you are doing wrong? Working ! Sit down! Grab a beer ,and watch some videos ! Go buy some stuff ,it's Christmas! But seriously ,some good ideas here if you have time to order something and have the inclination.

[Kevin Jenness]

Keep the stock removal to a minimum and avoid climb cutting especially on end grain. Bear in mind that where you might be able to control a climb cut on thin stock, you are working with material 3 times as thick as the shank of your bit, so you are taking a lot of material as well as inviting the bit to whip around.

Some years back my workmate was using a handheld router with a pattern bit and straightedge to trim the end of a passage door. He elected to make a climb cut, and as he transitioned from the rail to the end of the second stile the router caught and rotated into the base of his thumb. He nicked a tendon, and after a month of PT was lucky to get away without a permanent deficit, Needless to say that caught my attention. I do use climb cutting in some routing situations, but only with very light cuts and short bits. Even with a heavy shaper and power feed, climb cutting is not something you want to be using for significant stock removal.

[Greg Urwiller]

Thanks for all the advice! I know on the next end I'm going to bandsaw closer to the line. I was probably more like 1/8" all around rather than 1/16'' or less like I should be. I don't have much problem with the grain, but going around the top curl is a killer. I gouged pretty good at one point, then it caught enough it split the top curl in two. A real ragged split, it's going to take some finesse to get it all pulled together. The end is 1 1/2" thick with a 3/4" piece glued on the side at the top portion to widen out the "armrest" part of the pew end. Now I'm worried that this narrow, 3/4" thick, curved section will break even easier than the 1 1/2" section did. I've got a pattern cut out for it also and was figuring on doing it the same way. Now I'm not so sure this will work. The pattern cutter I'm using is a straight cutter. Would the spiral type have less tendancy to grab on the end grain? If so, I might have to order one of these.

I was upset this morning when this happened and I completely forgot the obvious. I built a new router table last summer with a PC 7518 in it. It's sitting in the corner just about covered up. All I have to do is glue in a dust collector fitting in the back and turn it on. Duh! All I could think about this morning was using my shaper. So, I'll go with this instead of the shaper and use the cutter I was using. Unless the spiral will work better. Thanks again. Greg

[david brum]

The PC router will work better for sure. Your old B&D router/shaper is a 10,000 rpm system, really designed for bigger diameter cutters where the faster rim speed of the cutter makes up for the slower rotation. If you're using a smaller diameter router bit with that system, it's hard to get a good cut. Your PC router is something like 25,000 rpm, so it's going to cut much cleaner using a smaller bit.

[Kevin Jenness]

If the shape you are cutting includes an arch across the end grain, you may want to approach it from two directions by using a top bearing bit from one face and a bottom bearing bit from the opposite face. That way you can avoid cutting "uphill" against the grain. This is probably what Rick Potter was referring to above, and is the approach used with the oldtime double spindle shapers with counter rotating spindles.

[Rick Alexander]

I've got a big spiral style pattern bit I got in a cabinet set from Sommerfelt that works great. I don't get near the grabbing with that style bit. It's the one in this set.

http://www.ebay.com/itm/CMT-800-520-11-Sommerfeld-Ogee-Cabinet-Making-Set-NEW-/180983550900?pt=Routers_Bits&hash=item2a2375d3b4

I'm sure they sell it separately. I love his bits.

[Prashun Patel]

A spiral bit will definitely help with tearout. Whiteside makes the Ferrari of compression, spiral pattern bits. They're pretty pricey, though. MLCS has cheaper ones.

If you have a drum sander or even drill press, you can pattern sand the trickiest parts on that. There exist rubber bushings that can be used the same way.

However, If I were doing a ton of pattern bandsawing, I'd get this:
http://www.rockler.com/bandsaw-duplicating-pin.

At best you might be able to eliminate the flushrouting step. At the worst, it'll make going up to the line easy.