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I was using a 1/4" round over bit in my router table and am continually getting tear up. Unfortunately my table router has only 1 speed. I tried to slow down my rate of feed then it burned. The bit is a Vermont American that has hardly been used at all. Could the tear out be caused by the bit (too cheap of bit) or is it because of the soft pine I'm using or something else I'm doing wrong?

Any ideas

Wood Circle Metal
 

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Pine is prone to tear out from a router bit. I've used the Vermont bits - not the best but sufficient. One thing you could do is learn to take baby steps. Don't expect good results with 1 pass. In your 1st go around, stay 1/3 away from the bearing. A 2nd pass should diminish the the completed task by 1/2... Then try to finish your profile.
 

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Some woods and particularly some boards are more prone to tearout than others, but I've not had good results from Vermont American blades or bits in general....new or not. It's a brand I've learned to avoid.

At a minimum, I'd look to MLCS, Woodline, or Woodriver as my entry level bits......Price Cutter, CMT, Katana is a better grade..... and Whiteside, Eagle America, Infinity, Freud, or Amana as premium bits.
 

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You might slow down your passes and take smaller bites. Your last pass will be just a skim pass.

You might try climb cutting (reversed routing direction) if you are very careful. It can be dangerous if the bit catches the stock. You need to move slowly and control the stock (if done on a table router) or control both the router and the stock if done handheld.







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+1 for taking small bites, finishing with a very small one.

Not so sure about climb cuts. Yes, a climb cut means that the bit cuts entering the work and not leaving, so less tearout, BUT...chances of a disaster when the router takes control of you are quite high, especially on a curved cut. I've done it successfully on straight cuts and on outside curves, but on an inside curve I'd be very nervous.

Another tip, use the largest diameter bit you can for the job, the angle that the bit exits the work is shallower as the bit diameter increases, so this helps reduce tearout.
 

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I was using a 1/4" round over bit in my router table and am continually getting tear up. Unfortunately my table router has only 1 speed. I tried to slow down my rate of feed then it burned. The bit is a Vermont American that has hardly been used at all. Could the tear out be caused by the bit (too cheap of bit) or is it because of the soft pine I'm using or something else I'm doing wrong?

Any ideas

View attachment 80779
look's like the bit is to small for the hole, or wood to big for the bit, look's like the top of the bit is rubbing , not making a smooth cut , use a bigger bit, or smaller wood, you should get a smooth cut in pine, take smaller cut's, my self i don't use pine , if that is what you have i guess use it, poplar would be a better wood to use, no sap in that wood, their are pine sap which causes burn's and lot's of bit build up good luck
 

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Single speed routers are normally designed to spin fast, too fast for my desires.

You mention 1/4in roundover bit, which can be run at high speed.

As mentioned in other replies some woods tear out more than others.

Pine tears easily. Vermont are not the best bits. If this is HSS (High Speed Steel) and not carbide tipped, it will dull faster than you expect.

Looking at your picture reminds me of the challenges woodturners face with bowls.

Part of the circumference cuts easily, the layer of wood in front of the cutting edge is a little longer and supports the previous layer while it is being cut.

The other part of the circumference, the layer in front is shorter than the present layer and so the present layer has no support resulting in tearout. Any wood can exhibit tearout.

Turners use different techniques, slower speed, different tools etc.

You cannot adjust the speed so the only options you have are multiple light passes with the final pass being very light. Climb cutting for the problem areas may work, but at your high speed may be difficult to control.

I would be prepared for needing some wood filler and sanding.
 

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grain changes direction around the hole

The tear out is where the end grain occurs. Raising the bit in small increments will "help"..... Let the tear out occur on the first pass, then do a clean up where you are taking off a minute amount of material.
Pine is notorious for grain changes unless it is very clear straight grained.

If you have a diamond stone, hone the flat edges of the bit until you get a uniform shine. Do not touch the curved portion. Vermont American is the bargain of router bits, and does not have the highest grade of carbide. It may work with a touch up, if not, go to a better quality bit....Freud, CMT, Amana, as mentioned.
 
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