Official Luthiers Forum!

So which do you cut first, and why?

_________________
http://www.presnallguitars.com

I cut the binding to depth then creep up on the purfling

the way I look at it, the binding sets the depth of the purfling cut.

I build a mock up using the binding and purfling as a go-no go gauge and test fit on scrap and as I cut the channel in the guitar. I like this to be tigh but not under cut.

I guess I should say I have an adjustable bearing guide so I can index futher down the side than if I had a bit w/ bearing set-upMichaelP38788.7513078704

I do the purfling first, because I can't see how to index off the side accurately (with a ball-bearing binding cutting set) if I cut the binding slot first. Then again, I don't have all that much experience in this area...

[QUOTE=Hesh1956] I like to make my bindings as deep down the side and as thick as possible. With this said I have to cut the purffing channel first or the guide ball bearing may fall into the binding channel when cutting the purfing channel.[/QUOTE]


   Hesh, I wish we could of had this conversation before I started routing for my binding/purfling. I was following the Cumpiano/Nathelson book and he recommends doing the binding first... Good if you have a guide that registers lower, very, very bad if you have the Stew-Mac/LMI binding router bit...
   My guitar now has an extra purfling on the top, AND, the back. When it first happened on the back I was blue in the face but I figured it was a normal human accident... When I did it again on the top, knowing full well about the dangers of the bearing slipping in to the channel, I left my shop and didn't return for a week! Man, I swear I didn't take my eyes off that bearing for more than a milli-second and it jumped in the channel

_________________
I'd like to be able to prove, just for once, that money wouldn't make me happy...

Binding first for me for all the reasons already mentioned. A majority of the texts on guitar building also recommend the same.

I'd especially emphasise the suggestion that one poster made to do a test run first.

Cheers Martin

I score my channels with the LMI gramil tool first. That gives me a reference to see where the router rode up because of the arch in the top. Then I route the purfling followed by the binding.

I do it that way for the same reasons as Hesh. I use a dremel with a small Stew Mac roller guide and I'm afraid I'll lose some of the reference making it hard to cut a clean purfling line. If I had a stationary cutter set up it might be a different story.

_________________
Joe Beaver
Maker of Sawdust

I use a homemade UHMW adjustable jig that registers across the entire side - no bearings, easy to get 1/4 inch downcut spirals - I cut the binding first, then creep up on the purf ledge until it and the binding fit tight. I am about to get a third PC 7310 lam trimmer, and make a second jig that is setup to cut the binding only - not to be touched unless the bit needs replacing.

The jig lets me adjust for any width and height binding or purfling. Iused to use something ala Larrivee and Laskin form the articles he wrote in FWW - but I hate not being able to see where I am routing - that jig is completely blind. This onbe also gets into tight cutaways quite easily.

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

Binding first for me too. I like to have this sorted to give me the reference for where the purfling has to go. As I use my adaptation of the Fleischmann-Williams binding jig I can use a normal routing bit and the laminate trimmer attachment follows the sides so even with long binding this is not an issue.

_________________
Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I do my top and back purflings first, then my binding ledges.
What "The Beav" does is a great idea. Scoring all the cuts with a gramil is a great move. I had a guitar I did with some acacia where the sides had some considerable runout. I had a bunch of tear-out as a result. Scoring with the Gramil would have solved the problem before it happened. You just never know with wood...I intend to buy one of those things one of these days. If I ever go back to building guitars that is.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Tony - how about a picture of your jig??

I am not familiar with a grammil. Is this similar to the purfling cutter that Stew Max sells - old Sloan tool??

Greatest little thing ever! I bought mine after my router slip fiasco. It's awesome to finish up near the headblock and tail-end where the router doesn't cut deeply enough because of the domes (if your router registers from the top). LMI, Schneider Gramil, 40 odd bucks.Alain Desforges38789.4965509259

_________________
I'd like to be able to prove, just for once, that money wouldn't make me happy...

Here is my jig - aluminum, UHMW plastic, and 1/4 20 threads all round, except the large bolt down the main fence, its 1/2-13. I made this based on a local Taylor repair guys jig - except his had different machined alum verticals to change the width of cut - nice, but expensive to have done. This jig can handle any binding purf scheme, no matter what the size. I use a 1/4 downcut solid carbide bit.

The bolt out the left is the width adjust, it helps set the distance from the bit for the vertical fence. The red UHMW keeps the vertical fence square as adjustments are made. The router mounts vertically from the bottom, the bit protrudes up thru the shoe, the right most black UHMW piece. It has a contact area about half the size of a quarter, so it can handle either the 18 or 28 radii I use. I notched out the main fence (it is actually made of two pieces, you can see the join, but it really doesnt matter, the area it rides on is huge compared to most jigs) to only register on the outer parts of a side while routing. Its fairly easy to control, and I do all the ledges in climb cut while the guitar is held in a big body clamp vise - this helps keep any tear out to a minimum.

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

SOme more info - the bolt head behind the vertical fence holds the fence down to the bottom plate - The plate that the fence is bolted to has a slot in it, allowing it to slide back and forth once the bolt is loose. The rear bolt sets the depth. So lets say you are setting up for binding - I set the fence shallow, route and see where I am at - then tighten the rear screw against the fence plate before loosening the hold down bolt. Every 1/4 turn of 1/4-20 is 12.5 thou, so its pretty easy to adjust say an 1/8 turn, adding 6 thou to the width of the route, tighten the hold down, route, then check it again. Within 3 or 4 adjusts, I get the width dead on, then do that route. This is the main reason I want to make another of these - to have it set permanently for a 85 thou wide binding channel. Depth is easily set by the router height of the the bit.

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

I cut the binding ledge first then the purfling.
I don't use the LMI bearings ,my set up uses a parallalagram type jig and use a downward cutting spiral bit.
Hope picture comes out OK.

Rick218

My set up has a bearing that contacts the side below the binding channel. I route the binding channel first, then do the purfling channel.

_________________
53% of all statistics are made up on the spot
http://driftwoodguitars.blogspot.com/

been awhile since I had cut channels until last week on current build.I did the binding first, will not do that again. I will from now on like before do the purfel and then the binding so can be more exact on more important channel, the one that shows IE binding

The primary reason I cut the top and bottom purfling first is because of the bearing. I can ride the side with the bearing well when cutting the purfling first, but if I did the binding first, there is risk of the bearing slipping into the binding channel and fouling up the purfling channels, and the top or back. No sense in risking disaster.

edit:
Now that I think about it, I did a style 41 top, and I had to do the binding first, because the small uhmw disc that rides the top needed the wood to sit on to cut the binding channel. If that makes any sense. Otherwise the binding channel would have been too tall.

Don Williams38789.6172453704

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

The results are pretty interesting. A half/half split... Hmmm, I think there's conspiracy afoot!

_________________
I'd like to be able to prove, just for once, that money wouldn't make me happy...

My jig registers off the sides much like Tony Karol's, but with bearings for contact points. I rout for the binding first, then purfling. It could be done either way really, this is just my habit. My jig is stationary while I turn the guitar around it.   

_________________
Rian Gitar og Mandolin

[QUOTE=Alain Desforges]

Greatest little thing ever!

Yeah baby... that's the one!

_________________
Joe Beaver
Maker of Sawdust

On my first, i did the binding first and purfling second and had major problems on both channels with my dremel and downward spiral. Since then, i bought a PC 7310 and the Stew Mac bit and bearings set, and i'm also thinking of making a jig that will register from the side and help me route freehanded, a bit like Michael Payne showed on a previous thread last week, i forgot to save the picture tho.