Is this a dull router bit? Bad technique? Or something unique to pine?`

Packard

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I am making some toy cars.  I am using a scroll saw to come within 1/8” to 1/16” of the pattern.  I then attach the pattern to the blank and using a bearing guided pattern/template router bit, I finish the cut.

The bit is little used and feels sharp.  But I am getting a ragged edge as indicated in the photo below.  I am referring to the area adjacent to the blue tape. 

I never work in pine (except to use framing studs), but this result seems wrong. This stock is 3/4” thick.  The pattern is 1/2” thick.

Before I order a replacement bit, I want to confirm that the bit is the culprit. 

Other possibilities are technique.  I am feeding fairly quickly to avoid burn marks on the wood.  Are the burn marks a product of a dull bit?

Despite my best efforts, a burn mark is visible at the front of the car.

And the only other possibility I can think of, is that pine is susceptible to this tearing.  My cross cuts (with a sharp blade on my table saw) see rougher than usually edges.

And a new finding for me, is a different type of kickback on the table saw with pine.  I got I hit in the stomach with a kicked back half of a loose knot.  No pain or bruise, but a what-the-heck-was-that response.

If it is the bit at fault, I would like to order it today.  If it is a mea culpa and I’m at fault, then I’d like to get the embarrassment over today also.

Most of my recent (within the last 10 years) purchase of bits have been from Whiteside.  I’m not sure of the manufacturer of this bit.  It is older but rarely used.  It is probably a Craftsman bit, so no telling who actually made it.

oEpVZhN.jpg
 
Cutting against the grain of a very soft fast growing wood with a straight bit will often yield this result. If the template was on the other side of the wood the cut would have been with the grain, mostly. But the best result would be with a spiral bit. The softer the wood the sharper the cutting tool required.
 
I think you've got a bunch of things going on here. A soft material, a dull/straight blade cutter and possibly a climb cut.

I'd start by trading in that straight blade cutter for a helical one, Whiteside & Woodpecker offer viable options. If these are Christmas presents, then you may want to stick with the Whiteside as you can probably locate one sooner than the Woodpeckers. Most Woodcraft stores stock Whiteside router bits.

Once you purchase a router bit that "shears" rather than "chunks", then some of these other issues may go away. 

Here's a Whiteside & a Woodpeckers.

[attachimg=1]

[attachimg=2]
 

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It's pine.

First, the burn is because we always dwaddle around corners.  Worst is the inside cuts, but even the outside curves people tend to slow down.

The roughness is because it's lifting and bending the pine grain.  Nominally, on a CNC, I'd leave a roughing offset and then come back again quick with the finish pass.  You can do something similar by building up your template with tape, although it's tedious.  But if you get the amount of material removed down to a smidgen, where the grain switches up, you can switch back and forth to and from climb cut on the final.

Or you just pony up and get a nice bloodletter bit.
 
I have been using a 1/4” radius round over bit (Whiteside) and that bit exhibited neither the rough texture, nor the burns. 

I will order a new bit today.  $45.05 + tax. 

Amazon has it in stock.  It will arrive on Saturday.  Amazon is running a couple days slow, I guess because of the holidays.

I will update when it arrives.

Does it make sense to have router bits sharpened anymore?
 
I’ve never sent a router bit to be sharpened but I have attempted to improve an edge with a diamond card when in a production pinch. Not sure it really helped…
 
Dull, straight-edge bit cutting against the grain.

As Cheese and Michael said, step 1 is a spiral bit. I would opt for one with bearings both above and below the cutter. This allows you to change the height of the bit and switch from template-on-top to template-on-bottom so you can always cut with the grain instead of against the grain.

As much as possible, feed from edge grain leading into end grain. Coming around an end-grain to edge grain corner is almost always going to blow out.

Taking another look at the picture, it's just as I would expect. You were feeding uphill on the profile and against the grain...double whammy. With a pattern/flush trim bit (bearing both above and below) you could have flipped the project over, changed the depth of cut and worked downhill with the grain...silk.

Softwoods exaggerate all the worst properties of wood, but also the best. Cutting with the grain you'll get a stunning finish, but go against the grain and it's a disaster almost always.
 
Thanks for the replies.

My template can easily be mounted either way.  I will have to study the grain from now on.

Regards,

Packard
 
As the others have said, you need to be cutting "down-hill" with the grain. What you have there is akin to rubbing a cat backwards.
 
I have looked at the pieces I have already routered.  I see I should have mounted the template on the reverse side.  I never considered that when I was mounting the template.

In any case I will both wait for the new router bit and consider the direction of the grain going forward.

Luckily, I have a bench top oscillating sander which should quickly remedy this on the pieces I have already templated.
 
It is 8:30 p.m. and Amazon promised delivery today by 10:00 p.m.

I just checked and my package is in a warehouse in Northborough, Massachusetts.  According to Google that is 210 miles from me, or 3 hours and 18 minutes by truck.

I guess their Christmas is busier than they anticipated.  It has been sitting in that warehouse since 12:35 this afternoon.  They’ve run out of trucks or drivers or luck.

Maybe I’ll see it tomorrow.

Happy holidays,, everyone. I probably won’t be able to post until after Christmas.
 
I just got an email from Amazon.  They now say my shipment has been delayed and will arrive by December 30th.  They are offering me the opportunity to cancel.

They still show that he package is in their Massachusetts warehouse, 3 hours and 18 minutes away.  I suspect that they have no idea where the package is, and they hope it will show up by the 30th.
 
Another email from Amazon.  They want me to rate the seller.  What should I write?

Never got the bit.
Amazon seems to have lost it.
Amazon will allow me to cancel the order on the 30th.
Will they let me reorder?

Asking for a rating on the seller before the product arrives seems a wee bit illogical.
 
There's so many depts and silos at Amazon that they make the military seem like a well oiled machine.  Not surprised.
 
Amazon found the misplaced router bit and it was delivered today, about a week late.  For an entire week they had it in their Northborough, Massachusetts warehouse.  It left there late yesterday.

I will try this out tomorrow.
 
Cheese said:
I think you've got a bunch of things going on here. A soft material, a dull/straight blade cutter and possibly a climb cut.

I'd start by trading in that straight blade cutter for a helical one, Whiteside & Woodpecker offer viable options. If these are Christmas presents, then you may want to stick with the Whiteside as you can probably locate one sooner than the Woodpeckers. Most Woodcraft stores stock Whiteside router bits.

Once you purchase a router bit that "shears" rather than "chunks", then some of these other issues may go away. 

Here's a Whiteside & a Woodpeckers.

[attachimg=1]

[attachimg=2]

The spiral bit arrived yesterday and I tested it today.  The bit is defective.  It leaves two highly visible, but tactilely minimal, parallel grooves on the routed surface.  It is quite time consuming to sand out. 

I am returning it tomorrow through Kohls, and then back to Amazon.com.

I did work out a solution though. 

The shape of the part dictates that regardless of which direction I run the router, part of the cut will be against the grain.

To resolve this, I am now drilling the pilot holes for the template all the way through using my drill press.  This allows me to flip the pattern over and use it on the reverse side and still maintain perfect registration. 

So I cut with the grain on one side, flip it over and cut the balance also with the grain from the other side.

I did try the spiral bit on a full piece, and I got startlingly worse results.  In fact it grabbed the stock, chewed it up and kicked it back at me.  The wound was very small, but totally unexpected.  Perhaps I did something wrong.  I have no idea.  I used it as I would have used a straight bit. 

I suspect the issue has something to do with the fact that the spiral bit is 1/4” diameter, and my other bits are 1/2” diameter.  (I have two.  One is only useful on thick stock, and uses a 1/2” collet; the other works for the thinner stock and requires a 1/4” collet.

In any event, the problem is solved.  I am saving $45.00 on the new bit. And I am thankful that the wound to my hand didn’t require a visit to the Emergency Room.

And I am thankful that I learned about going against the grain on soft woods.

I will post pictures tomorrow.
 
Packard said:
The shape of the part dictates that regardless of which direction I run the router, part of the cut will be against the grain.

Snip

It was really eye-opening to me using a shaper to realize that, on pieces like yours where the grain reverses on itself, you can simple flip the cutter upside down and reverse the rotation on the shaper. I recently did this on some 35mm vertical grain Douglas fir which seems intent on exploding any time I approached a climbing cut. I made marks on the template for "Normal" and "Reverse", the "normal" way, then flipped the cutter and reversed the spindle for the "Reverse" sections, in this way I was able to avoid any climb cutting.

I'm still a little shocked that the little 3/4hp 3/4" spindle shapers aren't more popular, they would seem to address a lot of shortcomings in router tables.....
 
Tom Gensmer said:
Packard said:
The shape of the part dictates that regardless of which direction I run the router, part of the cut will be against the grain.

Snip

It was really eye-opening to me using a shaper to realize that, on pieces like yours where the grain reverses on itself, you can simple flip the cutter upside down and reverse the rotation on the shaper. I recently did this on some 35mm vertical grain Douglas fir which seems intent on exploding any time I approached a climbing cut. I made marks on the template for "Normal" and "Reverse", the "normal" way, then flipped the cutter and reversed the spindle for the "Reverse" sections, in this way I was able to avoid any climb cutting.

I'm still a little shocked that the little 3/4hp 3/4" spindle shapers aren't more popular, they would seem to address a lot of shortcomings in router tables.....

I will post some pictures tomorrow, but I was amazed at the amount of damage to the surface of the climbing cut.

I’m working at a router table.  I marked the start/stop on each side of the template.  So, I screw on the template and look at the start/stop (just a continuous magic marker line) and make the cut. 

On some of the pieces there was a minute dimple where I switched sides on the cut.  But a few swipes with a hand sander eliminated that. 

This is the first time I am ever finding a defect in a Whiteside router bit.  It is a little disappointing.  I’ve always had unlimited faith in their products.
 
The 1/4 micro bits are for light feed engagement only.  You only get less (far less) than 1/8 feed surface.  Any more and it'll kick or break.
 
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