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  #1  
Old 01-04-2020, 12:33 PM
WilliamTK1974 WilliamTK1974 is offline
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Default Bridge Pin Hole Reamers

I've been doing some work on my Recording King RD-A9M. I bought it an unbleached bone saddle and nut, and a set of Iveroid bridge pins. I also have a fret file and crowning set coming so I can even up some of the frets closer to the sound hole.

Something I've noticed is that the bridge pin holes on the current bridge don't seem to have been drilled perfectly straight up and down. The Iveroid pins are a slightly tight fit, too.

Would some light and careful reaming take care of that issue? Also, StewMac sells a tool for this that's close to $100US. I've seen others that are quite a bit less. Is it really necessary to spend that much on the tool from StewMac to get usable results?

The RD-A9M is a decent guitar that seems to have some poor workmanship issues. I hope the company does a better job on their higher level instruments.
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Old 01-05-2020, 02:55 AM
nikpearson nikpearson is offline
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Default Ream the holes or sand the bridge pins

You’ve got a couple of choices: ream the bridge pin holes or lightly sand the pins themselves. Some brands simply drill the bridge pin holes so they have parallel sides rather than a taper. Reaming the holes with a taper will give a better fit.

I’ve also found that adding a (very) short slot at the front of the bridge pin hole allows the pin to seat more neatly. The slot can be made longer if the string break angle is flat.

If the pins a fairly standard I’d be tempted to try sanding these first. Replacements aren’t expensive when compared to a reamer. If you find you really do need a reamer then I got a pair Philadelphia Luthiery Supply. Better price than Stewmac and the quality is excellent. You’ll only need one reamer, 3 or 5 degrees, to match your bridge pins. 3 degrees seems more common. Readers suitable for this task need to be a specific size and they’re relatively hard to find.

Hope that helps.
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Old 01-05-2020, 05:27 AM
Bax Burgess Bax Burgess is offline
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The Stewmac Ivoroid pins are 5 degrees. When they are in place, do they rock back and forth when pressed from underneath, or an acceptably firm fit? If acceptable, then a sanding, if too loose, then a reamer and Ivoroid oversized pins.
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Old 01-05-2020, 07:31 PM
WilliamTK1974 WilliamTK1974 is offline
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Quote:
Originally Posted by Bax Burgess View Post
The Stewmac Ivoroid pins are 5 degrees. When they are in place, do they rock back and forth when pressed from underneath, or an acceptably firm fit? If acceptable, then a sanding, if too loose, then a reamer and Ivoroid oversized pins.
No, no rocking back and forth when I touch them from underneath. They seem in there pretty firmly.

The photo is a comparison between the factory pin and the Iveroid. The Iveroid is the longer one.

Even the factory pins don't sit straight up and down in the holes. I bought the 5deg pins because I thought that was common for Martins, and that RK designs tended to be copies of older Martin designs.
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Old 01-05-2020, 08:54 PM
Bax Burgess Bax Burgess is offline
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The factory pin's slot extends through the neck, whereas the Ivoroid's doesn't, and that might be why it's a bit tight, the string blocking a proper seating.
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Old 01-05-2020, 09:25 PM
WilliamTK1974 WilliamTK1974 is offline
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Here's what the factory pins look like in place. Irregular heights and leaning.
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Old 01-06-2020, 04:23 AM
ClaptonWannabe2 ClaptonWannabe2 is offline
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Quote:
Originally Posted by WilliamTK1974 View Post
Here's what the factory pins look like in place. Irregular heights and leaning.
Heck, practice sanding those pins first. Seems to me that sanding is better for risk/reward than reaming the bridge and top of your guitar. You can buy new pins easier than gluing material back into 6 holes you've made too large.
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Old 01-06-2020, 05:52 AM
slide496 slide496 is offline
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Pin apparently come at different angles - it took trying several different types to get ones that fit ok on the 2 machines I replaced them - one being a recording king which I no longer have. The other is a supertone 37-38.

I've both sanded pins and used a reamer. The one I got in 2015 (cheaper then) and just used when I replaced my Supertone bridgepins when one broke is from grizzly.com.:

https://www.grizzly.com/products/Gri...n-Reamer/H5808
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Old 01-06-2020, 12:42 PM
printer2 printer2 is offline
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https://www.ebay.com/c/1631533527
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Old 01-06-2020, 12:48 PM
Howard Klepper Howard Klepper is offline
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Originally Posted by printer2 View Post
Those cheap mechanics' reamers are not 5º--more like 7-8º. But the sellers have discovered that people are shopping for guitar pin reamers, and that there is always someone who believes they can get a free lunch.

They also will not keep the hole round because they are fluted all the way around, which tends to make the hole hexagonal and sometimes oval.
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  #11  
Old 01-06-2020, 01:19 PM
WilliamTK1974 WilliamTK1974 is offline
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Yeah, I knew better than to buy the cheapest of the cheap, but thought there had to be a good alternative to spending $100 for one.

I'm having issues getting good pics, but I did some practice sanding on the factory pins. Overall, they seem to fit better now.
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Old 01-06-2020, 03:58 PM
leew3 leew3 is offline
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Am I the only one who thought the title of this thread was the name of a new acoustic roots group?
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  #13  
Old 01-07-2020, 12:19 PM
printer2 printer2 is offline
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Quote:
Originally Posted by Howard Klepper View Post
Those cheap mechanics' reamers are not 5º--more like 7-8º. But the sellers have discovered that people are shopping for guitar pin reamers, and that there is always someone who believes they can get a free lunch.

They also will not keep the hole round because they are fluted all the way around, which tends to make the hole hexagonal and sometimes oval.
Just thought it a better alternative than holes which were drilled straight. I did not think the OP would have sprung for $100. Glad he has it resolved.
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Old 01-07-2020, 12:22 PM
WilliamTK1974 WilliamTK1974 is offline
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Quote:
Originally Posted by printer2 View Post
Just thought it a better alternative than holes which were drilled straight. I did not think the OP would have sprung for $100. Glad he has it resolved.
Well, sort of resolved. The factory pins look mostly correct. I did some sanding on the Iveroid pins, and while they look better than they did at first, they still seem to have a bit of sideways lean to them like the factory pins did prior to sanding them.
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  #15  
Old 01-07-2020, 04:47 PM
ClaptonWannabe2 ClaptonWannabe2 is offline
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Quote:
Originally Posted by WilliamTK1974 View Post
Yeah, I knew better than to buy the cheapest of the cheap, but thought there had to be a good alternative to spending $100 for one.

I'm having issues getting good pics, but I did some practice sanding on the factory pins. Overall, they seem to fit better now.

So I gave a decent suggestion on this site?
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