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  #31  
Old 03-02-2015, 04:17 PM
Jim.S Jim.S is offline
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Just to add to what Charles said in his last paragraph. The technique used to avoid tear out is called "climb cutting" and is in general to be avoided with a router because it can grab and pull the router along but in this situation it is the best method, you need to be on the ball though.

Stewy Mac gives a bit of detail HERE but you might find some more detailed info with Google.
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  #32  
Old 03-02-2015, 08:10 PM
Twilo123 Twilo123 is offline
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Quote:
Originally Posted by charles Tauber View Post
The issue in cutting rabbets (ledges) for the binding occurs on instruments whose tops and/or backs are not flat. If the base of the router sits on the curved/arched top or back, the binding ledges that are created are not of uniform thickness. The angle of the router bit relative to the instrument sides changes as the router base tilts while traversing the circumference of the arched top or back. This creates ledges of varying thickness - thinner the further you are from the center of the arch.

If you are only making one or two instruments, it is easy enough to just use the router with its cutter to create the rabbets. Follow that by using a sharp chisel or files to make the rabbets uniform in thickness. If you do not, when the binding is glued and then scraped flush with the sides, the thickness of the binding will vary.

If you are to make a number of instruments, you may wish to invest in jigs that will ensure that the sides of the instrument are used as the reference for the router. As long as the base of the router is maintained perpendicular to the instrument sides - that is, the cutter is parallel to the sides - the thickness of the ledge will be uniform. As you have seen, there are numerous ways to achieve that, from attachments to Dremels to large holding fixtures. All of them will work.

Regardless, pay particular attention to the sequence in which you route. In the "parlour guitar build" video you posted, he shows this about half-way through, though doesn't explain why. He routes from the widest point in the upper bout towards the neck, from the widest point in the upper bout towards the waist, then from the widest point of the lower bout towards the waist, then from the widest point of the lower bout towards the end block. This is done so as not to "catch" the wood and sever it along a grain line. If the wood does "catch", it can take a 1/4" or 1/2" piece of the top or back when it does so. You can reglue the piece, but it is best to avoid doing so to start with. With the amount of overhang you have, nibble away at it, rather than try to remove it in a single pass of the router. If you have access to a disk or belt sander, I'd remove nearly all of the overhang that way. A sharp chisel will also work, if you have that skill.
Thanks Charles. i do have access to a belt sander that i have been using upside down in a vice. i rounded out the headstock that way. i can try it with trimming the sides also. i noticed how he did it in the video and saw a couple others doing it like that so yes i will do that although the bouzouki has a different shape. i will just use the widest point and use the methods shown and also shown in the stew mac diagram link posted on page 3. since the bouzouki is a curved side i probably can't use the flat method like you were saying although the video i use as example is actually for a bouzouki and he uses the flat panel method which is weird right. with a belt sander do i still have to pay attention to the direction like the video was doing?
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  #33  
Old 03-02-2015, 08:14 PM
Twilo123 Twilo123 is offline
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Quote:
Originally Posted by Jim.S View Post
Just to add to what Charles said in his last paragraph. The technique used to avoid tear out is called "climb cutting" and is in general to be avoided with a router because it can grab and pull the router along but in this situation it is the best method, you need to be on the ball though.

Stewy Mac gives a bit of detail HERE but you might find some more detailed info with Google.
perfect diagram on stew mac thanks Jim! does the diagram assume the bit is moving in a clockwise direction?
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  #34  
Old 03-02-2015, 09:15 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Twilo123 View Post
with a belt sander do i still have to pay attention to the direction like the video was doing?
No. It doesn't matter when sanding.
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  #35  
Old 03-02-2015, 09:42 PM
Jim.S Jim.S is offline
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Originally Posted by Twilo123 View Post
perfect diagram on stew mac thanks Jim! does the diagram assume the bit is moving in a clockwise direction?
It does, don't think I have ever seen one spin the other way.
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  #36  
Old 03-03-2015, 08:43 PM
gpj1136 gpj1136 is offline
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I was thinking of a jig more like this.
http://acousticguitarbuilding.blogsp...nt-status.html

It's easy to build and they work fairly decent. I would go with a laminate router over a dremel
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  #37  
Old 03-03-2015, 09:14 PM
Ned Milburn Ned Milburn is offline
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Same router as yours. I made this attachment:



Just one piece of advice with a router - make sure you have a firm grip of it and never be complacent. It is really a tool with ferocious power and could cause a bad injury with a moment's brain fart.
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  #38  
Old 03-04-2015, 11:31 AM
Twilo123 Twilo123 is offline
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Yea I saw this last night http://www.kennethmichaelguitars.com...execution.html
Page 2 has the same diagram like stew Mac.
I don't have the skills to build my own jig at this point.
If I sand the sides down and route directly on top of the body even though I don't get the angles perfect I could chisel/sand out from there to make it uniform right?
I don't have a jig for holding the body either so could I just route around it without one like the guy did in the trimming video or will the body go flying when I try this or get tear out more easily.
For bouzouki would the grain cut method to reduce tear out be the same directions? I guess I just substitute the widest width and follow the direction arrows from there?
I am going today to at least sand down the sides....been a lot of snow around here lately.
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  #39  
Old 03-04-2015, 11:54 AM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by Twilo123 View Post
Yea I saw this last night http://www.kennethmichaelguitars.com...execution.html
Page 2 has the same diagram like stew Mac.
I don't have the skills to build my own jig at this point.
If I sand the sides down and route directly on top of the body even though I don't get the angles perfect I could chisel/sand out from there to make it uniform right?
I don't have a jig for holding the body either so could I just route around it without one like the guy did in the trimming video or will the body go flying when I try this or get tear out more easily.
For bouzouki would the grain cut method to reduce tear out be the same directions? I guess I just substitute the widest width and follow the direction arrows from there?
I am going today to at least sand down the sides....been a lot of snow around here lately.
You should be able to get acceptable results without a special attachment if the top/back are not domed too much. You may get acceptable results without touch up by file and/or chisel.

Similar directions to a guitar apply (regarding direction of travel). Just think of your bazouki as the lower bout of the guitar.

Clamp the neck down or have a friend hold it while you route. I wouldn't at all recommend trying it without immobilizing the instrument beforehand.
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  #40  
Old 03-04-2015, 01:20 PM
Twilo123 Twilo123 is offline
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Quote:
Originally Posted by Ned Milburn View Post
You should be able to get acceptable results without a special attachment if the top/back are not domed too much. You may get acceptable results without touch up by file and/or chisel.

Similar directions to a guitar apply (regarding direction of travel). Just think of your bazouki as the lower bout of the guitar.

Clamp the neck down or have a friend hold it while you route. I wouldn't at all recommend trying it without immobilizing the instrument beforehand.
thanks Ned. Let's see how far i am willing to go today lol. i should at least have the sides sanded down. nervous about the routing though. will probably just use test wood today and if i want something to do i will start doing the fretboard.
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  #41  
Old 03-04-2015, 01:29 PM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by Twilo123 View Post
thanks Ned. Let's see how far i am willing to go today lol. i should at least have the sides sanded down. nervous about the routing though. will probably just use test wood today and if i want something to do i will start doing the fretboard.
You'll not want to sand the sides to a final finish yet. Just sand now to remove any irregularities (waviness or undulations) if any exist. Wait till you get the binding installed, then do a final scrape/sand to flush and final surfacing.
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  #42  
Old 03-04-2015, 01:32 PM
arie arie is offline
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Quote:
Originally Posted by Twilo123 View Post
thanks Ned. Let's see how far i am willing to go today lol. i should at least have the sides sanded down. nervous about the routing though. will probably just use test wood today and if i want something to do i will start doing the fretboard.
why not use the gramil? how much is your time worth trying to figure out a router and the required locating fixtures and the cutters and bearings for something you might not ever do again?

with a 50 buck gramil, it's a 10 minute job. no router, no cutters, no bearings, no "jiggery" needed, no debating and fretting. and a nice how to video presented by mr. o'brien

easy work for the beginner right?

once you have your first done then scale up if you are going to make more. but for your first make it easy imo
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  #43  
Old 03-04-2015, 09:23 PM
Twilo123 Twilo123 is offline
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so i used the belt sander to get it down to 1/8" and used a blade to chisel down and finally sanded with 80 and then i believe it was 150. so now i have the tops flat to the sides. i believe this is called trimming. took me a couple hours to do everything since i am new to all of this but better manual and safe then sorry. besides this is all new to me so i am like a kid on christmas everytime i make it another step towards the goal successfully lol. i'm sure as i do more kits or finally try a scratch build i will need to have some better methods down for sure. for now though i am enjoying each step as it progressives albeit slowly.








Last edited by Twilo123; 03-04-2015 at 09:30 PM.
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  #44  
Old 03-04-2015, 09:59 PM
Twilo123 Twilo123 is offline
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now on the original back cutout never fully covered the heel (pic 1). i have some strips of back left from when i was trying to saw it off that i could use a single piece there. or should i get some veneer and cut it straight across there and use the veneer for the heel? i guess if i get the veneer i will wind up doing the headstock also. not sure where to get veneer though.

pic 1



Last edited by Twilo123; 03-04-2015 at 10:15 PM.
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  #45  
Old 03-04-2015, 10:25 PM
Twilo123 Twilo123 is offline
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also the bosch router i bought only accepts 1/4". the bit i bought from harpkit is 1/2". is there some chuck adapter i can buy to make the 1/4 larger to 1/2 or do i need to return 1 or the other?
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