Router Burning

[Rockytime]

My router with a round-over bit burns my projects. My router is a small trim router housed in a cheap Rockler $49 router table. The project that was burned is approximately 5X3-1/2 inches and 1/2" thick Oak. I did the round-over in two stages. Fist was with the router cutting shallow, the a second a finishing pass. The router is either dull, the router does not spin fast enough or whatever. I moved the wood across the bit as fast as I could but the bit will only cut so fast. On straight pieces it is not so much of a problem but on the curve I can't guide the piece fast enough. Perhaps I will just redo it with Poplar.

[OCtoolguy]

I've had that same problem. I attributed it to a couple of things. None of my router bits are what I would call top quality so probably not the sharpest. The other is my inexperience with using a router and probably either going too fast or too slow. But, I think in your case, you have a dull bit. Try taking a stone to it and see if you can put an edge on it. If we were a bit closer to each other, I'd let you borrow one of my bits to see if it made a difference. 

 

[Rockytime]

Thanks Ray. It is a HF bit so that is probably the answer.

[WayneMahler]

Les

Try cleaning your router bit. If it has a bearing, remove it before cleaning. Routing out curves takes a little longer which means the board gets fed slower to the bit. This can also cause burning the wood. Going in two passes is best, you could try even adding a third pass just enough to clean it up . Hope this helps some, good luck .

[NC Scroller]

I agree with Ray.  If you are going to use a bit once then a HF but might be good enough but bits you use over and over you want a quality carbide blade.  Consider Whiteside bits.  They are made in NC.

[Rolf]

Quality router bits make a world of difference. One thing I have done on hard maple, is I put a layer of blue tape on the edge that the bearing rides on. That offsets the bit by a few thousandths of an inch. so I will do what you did with a couple of passes. then for the final cut remove the tape.  As the others have said all router bits are not created equal. There are differences in the grain structure of the carbide that affect the edge.  

Oak is tough.

Nice project by the way.

Edited July 16, 2020 by Rolf

[ike]

The bit  you might try dressing  the blades with a stome.

Edited July 16, 2020 by ike

[Fedido]

After reading the comments, I have nothing else to add other than more passes. I have had to learn to make more passes myself. 

[ben2008]

Been there, done that.

My best advice  is to save up and buy quality router bits. That burning you are experiencing has plagued all of us at one time or another. I decided a long time ago to only buy the best. I did some research back then and bought a CMT round over bit. The results were amazing. I have not bought any bits in years. I have a couple of small flat diamond  sharpeners that I use to touch up the bits every now and then. I also have some Freud and Whiteside bits. I would not buy any other bits. All 3 are excellent in my experience. 

And the advice already given, More passes.

Best of luck with your project

Ben

Edited July 16, 2020 by ben2008

[Woodmaster1]

More pass is a great idea. Raise the router bit a little at a time and make the last pass taking very little off. Here is a picture of a homemade router table from Woodsmith plans that I use my trim router on.

[Fedido]

2 hours ago, Woodmaster1 said:

More pass is a great idea. Raise the router bit a little at a time and make the last pass taking very little off. Here is a picture of a homemade router table from Woodsmith plans that I use my trim router on.

Oh how I wish I had the space like you too...

[Rockytime]

Thanks for the many helpful reply's. I have carbide files to dress the bits and will give that a try. Also because my router is not a high end router making mini adjustments is kind of iffy.

[Bill WIlson]

Burning is more prevalent when routing end grain.  As has been recommended, a good quality, sharp bit and several light passes will achieve the best results.

If your router table has a starting pin, I might suggest trying a climb cut for the final pass, but if you aren't experienced and comfortable with the router, then please don't try it.

[OCtoolguy]

7 hours ago, Bill WIlson said:

Burning is more prevalent when routing end grain.  As has been recommended, a good quality, sharp bit and several light passes will achieve the best results.

If your router table has a starting pin, I might suggest trying a climb cut for the final pass, but if you aren't experienced and comfortable with the router, then please don't try it.

I for one would appreciate an explanation of what a "climb cut" is and how to execute it. Thanks.

 

[Bill WIlson]

5 minutes ago, octoolguy said:

I for one would appreciate an explanation of what a "climb cut" is and how to execute it. Thanks.

 

When routing on a table, you feed the stock from right to left, against the rotation of the bit.  A climb cut is when you feed the stock, in the opposite direction, with the rotation of the bit.  The problem with it is that there is a great risk of the bit grabbing the wood and yanking it right out of your hands.  The "advantage" is that it cuts less aggressively and that is why burning is minimized.

It can be done safely, but you really have to understand the physics involved and guard against losing control of the stock.  That is the purpose of the starting pin.  It's a pin that is attached to the router table top and it gives you a pivot point to brace the wood against.  It isn't necessarily designed for the purpose of climb cutting, but it can help you control the stock.

Just to reiterate, I'm not recommending that anyone try this.  It's kind of like operating your table saw without the guard.  Sometimes it may be necessary and it It can be done without physical harm coming to the operator, but it's not recommended.

[Rockytime]

On my milling machines I would use conventional milling moving the material against the rotation of the cutter then on the last pass I would make a very slight climb cut moving the material away from the rotation of the cutter. This gives a very nice finish. The applies to to the metal lathe. The bit moves forward to the material spinning counter clockwise and then reversing the cutter a very smooth surface is left. I would not ever have the nerve to climb cut on the router. Lots of good answers from this group.  I will try touvhing up the round over bit with a diamond card file and also try a new cutter which I have.

[tomsteve]

On 7/15/2020 at 11:00 PM, Rockytime said:

Thanks Ray. It is a HF bit so that is probably the answer.

ive noticed quite a difference in cut and finish between my HF bits and my freuds. iirc, the quality of the carbide can make a big difference and i dont think HF uses very high quality carbide

Edited July 20, 2020 by tomsteve

[Paladin]

I was having the same problem with some cheap Menards bits.  Purchased a Freud roundover, and haven't had a bit of burning since.

[amazingkevin]

On 7/15/2020 at 10:48 PM, octoolguy said:

I've had that same problem. I attributed it to a couple of things. None of my router bits are what I would call top quality so probably not the sharpest. The other is my inexperience with using a router and probably either going too fast or too slow. But, I think in your case, you have a dull bit. Try taking a stone to it and see if you can put an edge on it. If we were a bit closer to each other, I'd let you borrow one of my bits to see if it made a difference. 

 

We need to be neighbors friend!!!

[Rockytime]

Many thanks for all the information. I cleaned up the project to be usable. I did sharpen the HF bit somewhat. However, I will get a quality bit. Unfortunately I need it so infrequently. Were I 10 years younger I would not hesitate. But since...How long will I be around?

[OCtoolguy]

17 hours ago, amazingkevin said:

We need to be neighbors friend!!!

Well, we will be much closer once I relocate but still a ways away.

 

[OCtoolguy]

16 hours ago, Rockytime said:

Many thanks for all the information. I cleaned up the project to be usable. I did sharpen the HF bit somewhat. However, I will get a quality bit. Unfortunately I need it so infrequently. Were I 10 years younger I would not hesitate. But since...How long will I be around?

Les, that seems to be my buying criteria anymore also. I look at what "lifetime" guarantee really means now.

 

[mifon1]

One thing you might try is taking a spray bottle of water and spraying the areas with burning. Let the board dry. The water will leave the grain raised just enough that another light pass with the router and the burning should be gone. Give it a try.

 

Regards

Mike in TN

[John B]

6 hours ago, mifon1 said:

One thing you might try is taking a spray bottle of water and spraying the areas with burning. Let the board dry. The water will leave the grain raised just enough that another light pass with the router and the burning should be gone. Give it a try.

 

Regards

Mike in TN

Good tip Mike.
I will have to try that.