Official Luthiers Forum!

Greetings,
I've been using the neat jig Tony Karol described for making bridges and drilling bridge pin holes for about a year now. It's a great design. I can't find the post where he describes it but maybe someone else has it. Here's a little mod to make lining up the starting points for drilling the pin holes easier. First rout the saddle slot (mine are 3") and mark the centerline of the slot.

The mod is two pieces.

1. A surrogate saddle with a centerline mark

2. A spacer to mark the set-back from the saddle slot with marks for the starting point for holes 1 and 6 for a given string spacing. A nice feature of his design is that the bridge pin holes parallel the saddle slot and this helps you be sure they are parallel. I use a distance of 0.3" from the back of the saddle to the center of the bridge pin holes so the spacer is 0.3" wide. The bottom of the spacer has the same radius as the top of the bridge.



Put the saddle in the slot



Line up the spacer with the centerline and clamp to the saddle




Draw a reference line along the edge of the spacer and mark the starting points for holes 1 and 6. Transfer to the Karol pin hole drilling jig and line up starting point 1 and off you go. Marking the last hole allows you to verify your drill press jig is set up right.

Terry

_________________
It's not what you don't know that hurts you, it's what you do know that's wrong.

Now why didnt I think of that ..... BRILLIANT . Will be making one of those maybe tomorrow !!!!

wont need it all that soon though .. I whipped up the rough ins for 14 bridges last week as I needed one for a new guitar .... when you are in the mood ... just do it !!!

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

Thanks a million Tony. 14 bridges would almost last me 2 years. I don't make that many at a time because at my age I might not be around to use the last one!
Terry

_________________
It's not what you don't know that hurts you, it's what you do know that's wrong.

Thanks for sharing that. Where can I see the Karol drilling jig please?

Right here !!!!

So, I use a bearing bit and the template ot create the back ridge. Then the slot is done with either an 1/8 or 3/16 downcut bit - the fence is set to give the right angle required for the slot, and the stops set hte length. Then the bridge holder keeps the pin line parallel to the slot. The last is too allow the holder to slide, using the planed and measured spacers to give the proper hole spacing. Not in this pic is the latest one I made - it precuts the ends from the centreline on the TS to give a 6 1/4 inch length to the rough blank.

Like I mentioned, once you get set up, its easy to bang off a bunch .. so thats how 14 got roughed in (back egde, slots, and pin holes)- took about a hour max.

Edit - I have added lockable (1/4-20 knobs and threaded inserts), movable stops to the slot jig now - no more blocks and clamps. Also added a depth gauge to the edge of the slotting jig - easy to set - I route down and leave about 1/8 inch on the bottom of the slot.

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

Thanks Tony.