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I'm venturing for the first time into pinned bridge territory so have and will have over the coming weeks a number of questions. If they are basic to you I apologise in advance.

I'm making a guitar-cittern with 5 unison pairs of strings but will be using 5 holes in the bridge, 2 strings per hole. On Howard Klepper's advice I am using the Stew Mac ebony unslotted oversize bridge pins with 5 degree taper.

First question - what size do I drill the initial holes in the bridge (prior to reaming)? The Stew Mac spec shows the pins with a diameter of 0.235" at the top of the taper and 0.15" at the bottom of the taper.

Second question - do I use the same size drill to drill through the bridge into the top and through the bridgeplate?

Third question - when do I ream? When the bridge is glued on?

Fourth question - is the bridge slotted for use with the unslotted pins after the bridge is on and the holes reamed, or do you slot the bridge, then glue on and then deepen the slots to include the top and bridge plate?

Fifth question - are the length of slots in the bridge the same as the diameter of the string?

Thanks.

_________________
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

Dave



I would go for 4.5mm/5mm and yes same drill for all, Ream after bridge is on, I usually just drill the two outer holes for positioning and then do all the others once the bridge is on (I drill all the holes in the bridge when I make it). I do the slotting after everything is on and reamed out, at a minimum the slots for unslotted pins must be slightly bigger than the diameter, to allow free movement.RussellR38846.4171180556

Dave one other thing, ensure you have a wooden caul clamped behind where the drill will come through when you drill the holes through the top and plate or you can get nasty tearout where the drill exits, which will effect the seating of the strings.

Hope some of this helps.

[QUOTE=RussellR]
at a minimum the slots for unslotted pins must be slightly bigger than the diameter, to allow free movement.[/QUOTE]

Russell,

Many thanks for this.
In the above quote are you referring to the sideways measurement or front to back measurement of the slot. Or both!

_________________
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

You definitly want to ream the holes before slotting the bridge - the reamer won't work well after the slots are cut. After drilling the bridge pin holes through the top and bridge plate, I countersink the holes, ream, test fit the pins and then cut the slots.

                Paul









             paul harrell38846.4285185185

Both Dave

the side to side is obiously crictical that the center of the slot hits the path you want your string to take, but, you can minipulate the break angle a little with the front to back, you wan't the slots to be a tad bigger so the string can't bind.

I know that Maton Guitars angle the bridge pin holes back slightly, may be 5 degree, away from the saddle. I do not know if this has much of an advantage but my old Maton dred sounds very nice. Anyone here doing the same?

Cheers

Kim

I'm pleased of this thread Dave ,as I started a thread with a similar question. That of shared bridge holes.

Just for your interest here is a pic of a " Holzapfel " built circa 1900 's , so the idea isn't exactly new . I just wonder how the design holds out

The three rear holes were for brass dowels which have since been replaced.

Regards KiwiCraig

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CRAIG LAWRENCE of AUSTRALIA
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at a minimum the slots for unslotted pins must be slightly bigger than the diameter, to allow free movement.

That nearly completely defeats the purpose of using solid pins and slotting the bridge....

That nearly completely defeats the purpose of using solid pins and slotting the bridge....

Why is that Mario ?RussellR38847.5860185185

The main reason for using solid pins is that we are able to tightly fit the string's afterlength and pinch it tight against the bridge.

I stand corrected, I didn't know that was part of the function of solid pins.

Thank you Mario

Is the purpose to ensure the string seats cleanly ? or prevent any rattles ? or ????RussellR38847.6152314815

Not all the string's energy stops at the saddle; a lot of it goes past. If we let it flop around, it is lost as heat energy; if we capture it via perfectly fitted pins, we can put it to use. A small, tiny perhaps, detail, but get all these details working for you, and the gains are clearly audible.

Where do we place the mute on a banjo or fiddle? Behind the bridge, in the afterlength....

Thank you Mario

On some early builds I had problems with string binding in the slot so I guess from that point on I thought the string need to move completely freely though the slot.

What you are saying makes perfect sense, guess like all the work on a guitar it has to be just so, so that the string is tight without binding in the slot, you learn something new every day, I will be adapting my methods.