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This is related to the harp guitar. If you will notice in my avatar, the bass peghead has a hardwood joint to the top which looks like a curvy chevron. I want to be able to carve a channel between the two parts for inlay. Maybe a 1/4-3/8" wide (following the curves). I have found this to be a rather difficult problem. So I was hoping there was a way to create a template and use a router. But even if I did create a template, it seems to me that the router bit (say an endmill) would eat into the template due to the shallow depth of the channel (0.1").

So how do I work through this? Grind an endmill down to length and use the shaft as a bearing guide? And what about the template? How would you construct it?

BTW, due to the nature of this beast, it is VERY difficult to get a good, clean joint of the top to the peghead plate. Thus the need for some inlay work to clean it up. Its not impossible, but very time consuming and frustrating. Getting it "close enough" then finishing off with a machined channel looks to be easier.

Thanks,

Mike

Maybe you should check out the "drill press router" video on LMII.com. I haven't tried that yet but it sounds like it might work for you

I would make a template, and then use a router base template guide and whatever bit width you need.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Yeah, I saw that drill press router. I almost said "nah" to that until I stopped and thought about it. That's the Robbie O'Brian thing, right? I ordered drill blanks for that a while ago.

I think, still, the template is the hard part. Maybe I am over-thinking this.

Mike

I'm with Tony , a template and a collar bushing. If you use a inlay kit you can even cut the inlay piece to a perfect fit. As a matter of fact, you can cut the inlay strip and use the inlay kit to make the routing template.

Off to google... what is an inlay kit?

Here you go.
http://www.woodcraft.com/Product/200139 ... -9500.aspx
HF also has one for $10 but it isn't a carbide bit just HSS. I'd get the Whiteside with the bit. I can't say it enough that this and also a whole collar set is really helpful for making jigs and building molds. I show tips on how to use these in some of my YouTubes. Once you grasp the idea you will put it to use plenty of times. I used it to make the template for my bridge clamshell jigs and use it to make my building molds and bending forms templates. I have a Tut in the MIMF library on how to use it for making molds. Check it out sometime Mike. Also my bridge youtube explains it some.

I want to use my bosh colt for this. Whiteside or PC bushings? I belive I will need an adaptor... right?

Mike

Yes, Mike you will want one of these base plates.
http://www.amazon.com/PR010-Subbase-Thr ... 948&sr=8-8

Chris,

OK, I have setttled on the tools. It sounds to me (since you are recommending the threaded plate) that you prefer the Whiteside or PC inlay kit over the Bosch inlay kit which uses the twist and lock base. It seems the advantage to the threaded plate is that is uses threaded templates (without a twist and lock adaptor). Plus, I kind of like the brass templates (later) since they would be easier on the bits given a mishap.

Your final thoughts on this would be appreciated. For now, it looks like I am going with the threaded plate, conical aligner bit, and the Whiteside (or PC) inlay kit. Good?

Mike

PS: Welcome to the Classifieds! You have some neat stuff in there!

Mike I have had PC routers for years and I bought the inlay kit years ago as well as a bushing / collar kit that was the threaded type. I don't even know if they had the other type then? I have found that most routers and bases are setup for these collars. I thing the other companies just designed their own system to get more of the market or whatever. The collars don't thread into the base though, they have a threaded retaining ring and the base is stepped. I can't say anything about the conical alinement tool but the Whiteside kit comes with an alinement or centering tool for it. And for using a 1/4" collar I'll use a 1/4" drill bit or rod. I'd put the whiteside collar and centering bit in the router and base plate when you mount the new base plate to the router as it should center the base from the start. I haven't changed out my base on my colt yet but I never had a problem with my PC bases being off. At least they line up dead nuts on. But it never hurts to check them when precision is needed.
I think that once you start using these collars and the concept clicks you'll see how usefull they can be. Just remember to keep the template to the right of the bit in the direction of travel. It will help to prevent the the router from drifting off the template and possibly cutting into your work. Depending whether the work is under the template or outside the template. But the point is it will help prevent drift from the template. But be aware that's when there isn't any material removed. If you have a wide groove and you are opening up a groove you might not want to be climb milling to open it up or the router could bite in and get away from you. You'll have to make that call depending on the amount of cut. Hope this makes sense?

The little Bosch Colt is not setup (as delivered) for the threaded collars. It may be that they accept the type collar that uses a retaining nut. I would need to measure the hole. I think I will just order the Bosch threaded plate and go from there.

Thanks! Oh, and yes, I followed you on your other points. Again, thanks

Mike

one tip I can give is to make sure you have the sucker well tightened...I was routing out a 3" deep pocket once (yes, I was doing it in successive passes gradually getting deeper each pass...I had also drilled out most of the Ipe with a spade bit) and the collar loosened up which led to the router bit eating through it which in turn led to the bit cutting into my template and almost hosing the project..I was using the cheaper PC collar assortment which is pretty thin material and was easily cut through, the good thing being it didn't ruin the rather expensive 4" long mortise bit)...making a new template and careful use of epoxy to fill and putting the screw up on the back side worked in my case, but I dont' think would work to well on a guitar...

Yeah Mike O., the colt doesn't come with the correct base. You need the base in the link.
Hey Mike, I never have used collars on something that deep. Once I have enought cut out I take the template off and use a flush cut with a top bearing if at all possible. But I agree that you have to watch that you don't bottom out the collet nut on the collar. Don't ask.

OMG! This channel template stuff is difficult at best for anything other than a straight channel or circular (arc) channel. Try doing this with a curved channel like that at the top of the harp guitar!!

Mike

You will have to explain. Are you having trouble making the template?

Chris,

It is difficult to explain. But I will try. BTW, I did figure it out. Look at my avatar or any pic of a Dyer harp. Attempt to come up with a template that will allow the use of an inlay kit. It will not involve cutting (with a bandsaw) the shape of that compound, multi-curve, and then separating the two resulting parts for a template.

That would work for a straight line inlay or even an "arc" cut. But with curves that are complex, no way. Trying to do it so that visually the inlay has the same width throughout is tough.

Mike

Mike a picture would help but I think I get the idea if you are talking about a compound curve of some type. It might be something that has to be hand carved or shaped possibly? I guess I'd have to see it to get a clear idea.

This is an example of what I am doing. I used my plans to make a cut in the template board then spaced them apart like in the first picture. You can see that the inlay area is not an even width and it is because of the compound curves. My next post will be my solution to this. BTW, I have made no cuts on the guitar yet... good thing, huh?

Mike

So my solution was to use the bottom half of the cut (tan area) and make a tracing wheel out of acrylic to give me the correct spacing (taking into account the cut thickness uf the bearing in the inlay kit) to make a new top half of the template.

Other than that, I do not know how else I could have done this.

Mike

Mike,
I would make and template of the cut. Then carpet tape it down to some 1/4" or larger material( Plexi or polycarb would be nice) and have a sacrficial piece of wood under it. Then use the inlay kit with the small bearing only ( the larger bushing/bearing removed) and route around the template in a clockwise direction. Take several passes to get through the new routing template. That will be your outside template to cut the channel and to cut the inlay. Although you will have to do some hand cutting due to those sharp points as the bit won't be able to cut one of them for each opperation. Your channel obviously can't be wider then the 1/8" diameter of the bit. If you wanted to use a smaller dia. bit you would have to do the math and more then likely make a custom bushing set. Or you would have to use something like Kieth MacKensie's inlay duplicator/ Pantograph.




If you can do it the way I explained it and finish it up with a dremel and knife then you probably will want to cut a hole out of another piece of material the same thickness as the original template piece and the hole being large enough to fit around the piece leaving space for the router bushing to clear. That will keep the router level when making the template. A plunge base would come in handy here too. You might also be able to come up with a simple pantogragh to make the cut with smaller bits too. Hope this makes some sense.