String ball ends don't fit thru bridge holes

[southgate409]

I have an Recording King RO-318 that the string ball ends don't fit thru the bringe holes from the top to inside the guitar. As a work around, I strung it from the inside out. Just wondering what the best longer term solution might me. I was thinking about taking a round file and making then slighty larger so the ball ends would fit.....

[runamuck]

You need a reamer that's tapered to the same degree of the pins you use. Don't use a file or you will have big problems.

[Piercast]

Originally Posted by runamuck

You need a reamer that's tapered to the same degree of the pins you use. Don't use a file or you will have big problems.

^^This. As those are $$$, you’ll be better off taking it to a reputable luthier. You'll avoid ruining the bridge AND the top.

[southgate409]

Interesting, I may just live with it. Its only an issue for a few of the strings during string changes. I found the easiest solution is to work all 6 strings thru from the inside. Just makes fiddling with the saddle during the setup process a little difficult. Once I get it to where I want it it won't be an issue.

[phavriluk]

One person's opinion/take:

OP: do the bridge pins fit well? Can you get a lighted mirror in the soundhole so you can see if the installed pins fit snugly at the bottom? If so, then using twist drills in a pin vise one step at a time, enlarge the bottom of the pin hole
until the string ball passes through from the top.

If the bridge pins sit proud, then ream the bridge pin holes until the bridge pins seat well and see if the string ball end now passes through from the top. If not yet, see above.

While it's nice to be careful, I think agonizing over reamer angles approaches overkill. A 'General' brand reamer from the hardware store has done me well.

Like somebody mentioned already, stay away from files.

[DickHutchings]

No need for an expensive reamer. Just get a drill bit slightly larger than the ball. You won't be removing much wood and the taper will still be there.

[southgate409]

Originally Posted by DickHutchings

No need for an expensive reamer. Just get a drill bit slightly larger than the ball. You won't be removing much wood and the taper will still be there.

Thats an interesting solution as well. Makes me wonder how the strings were installed at the factory. I actually cut the factory strings ( used guitar I purchased and the strings were certainly the orginals ) and pulled thru from the bottom. Next string change I will take a touch off the saddle and look at the bridgepin holes more closely.

[Rudy4]

Most Martins (for the last several years) have been drilled straight through, no taper added to the pin holes.

I won't comment on what I think of this. You can find the right taper reamer normally sold for violin pegs on ebay for around 10 bucks.

Do NOT use a general purpose 7 / 8 degree shop reamer if your guitar is important to you.

[John Arnold]

Many modern slotted thermoplastic bridge pins are too small. If you drill and ream to fit the pin all the way to the bridgeplate, the hole will be too small to pass some string balls. While the diameter of most string balls is the same, some have rounded corners (example D'Addario) that will pass through a smaller hole (0.182" across the corners).
There are multiple solutions. If you insist on using the throwaway pins and strings with sharp corners on the balls, you can use a proper size drill (usually around 0.190") and enlarge the bottom of the tapered hole. I prefer unslotted pins that are slightly larger....1930's Martin style with a 5 degree taper (examples are Waverly and Antique Acoustics). Those require slotting the bridge and bridgeplate, which will also help solve the problem.
Most modern Martin pin holes are step drilled, rather than taper reamed. The hole in the bridge is 0.202", while the drill typically used to drill through the top and bridgeplate is 3/16" (0.1875").

[runamuck]

Originally Posted by John Arnold

Most modern Martin pin holes are step drilled, rather than taper reamed. The hole in the bridge is 0.202", while the drill typically used to drill through the top and bridgeplate is 3/16" (0.1875").

When you say, "stepped drilled", do you mean that the bit they use is tapered or that they use use various sized bits?

[Bob Womack]

Well, now. Has anyone considered that the balls probably had to fit through the top for the guitar to leave the factory? Don't raise the bridge, lower the water. Has anyone considered looking for strings with ball ends that will fit?

Bob

[southgate409]

Originally Posted by Bob Womack

Well, now. Has anyone considered that the balls probably had to fit through the top for the guitar to leave the factory? Don't raise the bridge, lower the water. Has anyone considered looking for strings with ball ends that will fit?

Bob

I was replacing the factory strings with EJ16 strings. When replacing, the low E string came out fine and the new EJ16 went in from the top. The A string ball would not go thru the top, so I snipped it and the rest of the strings and removed them from the bottom.

It is quite likely that the factory strings all went thru the top fine.

I was thinking that I would get the string issue figured out before I glue the pickup sensors to the bridge plate.

[John Arnold]

Originally Posted by runamuck

When you say, "stepped drilled", do you mean that the bit they use is tapered or that they use use various sized bits?

Two sizes of regular drill bits. The bridge is completely made before it is glued on. That includes the pin holes in the bridge itself, which are a slightly larger size. The holes through the top and the bridgeplate are drilled after the bridge is glued on, using the slightly smaller bit. In other words, the bridge acts as drill guide for completing the holes.
Note that these two sizes create a hole that is a bit small for the standard Martin pins, which often stick up above the bridge as much as 1/8" when Martins leave the factory. But a few turns using a quality 5 degree reamer will improve the fit, allowing the pins to seat down to the collar.
When I make a bridge, I drill the holes to the smaller diameter, which better guides the drill when drilling through the top and bridgeplate. It does require more reaming time to fit the pins, but IMHO, it gives better results.

[runamuck]

Originally Posted by John Arnold

Two sizes of regular drill bits. The bridge is completely made before it is glued on. That includes the pin holes in the bridge itself, which are a slightly larger size. The holes through the top and the bridgeplate are drilled after the bridge is glued on, using the slightly smaller bit. In other words, the bridge acts as drill guide for completing the holes.
Note that these two sizes create a hole that is a bit small for the standard Martin pins, which often stick up above the bridge as much as 1/8" when Martins leave the factory. But a few turns using a quality 5 degree reamer will improve the fit, allowing the pins to seat down to the collar.
When I make a bridge, I drill the holes to the smaller diameter, which better guides the drill when drilling through the top and bridgeplate. It does require more reaming time to fit the pins, but IMHO, it gives better results.

Thank You.