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I had some tearout the last time I did binding channels. I did it as per the Stew Mac diagram below. Is this the right way?
Are there some other precautions I can take. I have the StewMac Tru Channel jig.


http://www.stewmac.com/shop/Tools/Speci ... es#details

Thanks

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Wisdom is justified by her children

I always spray my top edges with shellac to make them a bit more brittle.
I use the stewmac climb cuts for the top only. for the back, I just turn it clockwise all the way around. Never had much problems with tear out.
I also clean my bit between every cut. I just use acetone.

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Lance@LuthiersForum.com

Mark : That is a very good article in my mind. One thing I've found very helpful over the years is to NOT take the full depth of cut at one time. If I was to use a binding that was .085 by .250 as an example, I would set my cutter to take a cut of about .035 by .250. Do that all around and then set for your full .085 depth. Since starting to do this I've had very little trouble with blowouts depending on what wood is being used for the guitar.
Tom

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A person who has never made a mistake has never made anything!!!

Lance : Wonder if you received my e-mail...?
Tom

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A person who has never made a mistake has never made anything!!!

Thanks guys we will see how it goes tomorrow.

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Wisdom is justified by her children

Hi Tom,
I did and responded and was waiting for a response to be sure I make the correct changes.

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Lance@LuthiersForum.com

I do my cuts clockwise (the same way the router bit is turning) for both the top and back and as long as you go at a normal pace you shouldn't have tear out. I don't like the stew-mac diagram. It takes something easy and makes it out to be something complicated. Go in a clockwise circle and as you start your cuts dont just plow into the wood at the starting place. Slowly enter the wood as you move along in the direction you are cutting. I usually get to full depth in a couple inches, then once the cut is complete I go back and finish the job at the beginning before moving the clamps. I take the whole thing in two passes. When in doubt going SLOWLY will solve most problems. Lastly, the member who posted about clean and sharp bits is absolutely correct. I have a really well sharpened bit that I inspect between passes, which is what allows me to do this operation the way I do it.

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http://www.sixgunguitars.com

It is all about the angle of attack of the cutter . You do have some delicate areas and the Stew Mac layout is not bad . Still climb cutting can also pose some problems . You can cause compression fracture . My best advice is to take nibble cuts and take your time . The more wood you need the remove the more care you need to take.
I have done the wide cuts first and I have done the side binding first. I can't say that one way is any better than the other. If I feel the top is too brackish and may split during the process I will use tape in the area of the bouts for the first inch width of grain. I also like to use tape where the bearing will ride , then I pull the tape for a neat clean out cut .
The more you do the better you get at it

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

deleted

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks for the help guys. This job went well. The only problem I had was the end graft. It is a brittle wood and it got blown out in the process. I did a couple coats of shelac, cleaned and touched up the edge of the bit and did it all in one pass going counterclockwise(climb cut). My best results yet, nearly perfect. Just have to redo the end graft.

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Wisdom is justified by her children

I use a gramil, to knife the outline, so that tearout is eliminated. It isn't really possible to cut the channel properly without routers that have clockwise and counter clockwise rotation, and appropriated bits. I don't do that, so I take the time to knife the corners.

On sharpness, the carbide bit that came with my Hitachi router was sharp enough to shave hair. I wish more bits were like that.

tear out is avoidable when you understand the angle of attack of the bit and how it works. There are times you should climb cut and times you shouldn't . I do mostly climb cuts but I don't to it on a hard pass . What it all comes down to is matching the cutting speed and feed rate. too fast can cause tear out and too slow will cause burning.
Also bits do not last forever .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

"tear out is avoidable when you understand the angle of attack of the bit and how it works."

True, what I see in various places though are diagrams that imply that it is possible to cut with the grain if one simply starts and stops in various places and changes the direction of feed, these cuts may be preferable but one is still cutting against the grain. I am sorta surprised that nobody has come up with something that allows all the cuts to be with the grain, but when even Taylor hasn't bothered, it presumably isn't necessary.

I'm glad to see some agreement. It's all in the speed you work the router and how true you keep it to the work surface. I go clockwise the entire time, where the bit is trying to drag me faster. I keep it to a steady pace, not slow but not fast and I NEVER have any problems. You will get used to how fast you can do things, and again when in doubt, go slower.

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http://www.sixgunguitars.com

Tom I start at the widest part of the upper bout and route towards the neck. 2nd cut start at the same place and route towards the waste. 3rd cut starts at widest part of the lower bout and router to the waist and then to the heel. repeat on the other side. All cut cuts will be with the grain. Last step is to take one complete cleanup pass.

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I do it exactly as Bob describes

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Rian Gitar og Mandolin

Counterclockwise is conventional cutting. Unless the router was upside down?

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

I second that. I also only take a 1/16" at a time as well for extra insurance.