Results 1 to 5 of 5

Thread: Grover 409 Tuner Installation Guide for Eastman F-style Mandolin

  1. #1
    Registered User Mando Esq's Avatar
    Join Date
    Sep 2022
    Location
    New Hampshire
    Posts
    105

    Default Grover 409 Tuner Installation Guide for Eastman F-style Mandolin

    Christmas brought this very good boy a new set of Grover 409 tuners.

    I have had my 2016 Eastman 515 for over two years now and I have no major complaints about the tuners that came with them (either Schallers or Pingwells, I have never been able to figure it out). However, I wanted tuners with a higher turning ratio to make fine-tuning the instrument (especially those damn A strings) easier, and avoid the bouncing-back-and-forth-over-the-tuning each time you turn the tuner juuuust a little bit. The current tuners are approx. 1:14 or 15 ratio. The Grover 409s are 1:18.

    I did as much research as I possibly could about which replacement tuners would fit the Eastman without needing to do any major drilling or surgery ("Dammit Jim! I'm a lawyer, not a luthier!"). Forum topics about replacement tuners for Eastman mandolins are fairly common, but I didn't find as many detailed posts or answers as I was hoping. A very common recommendation was Grover 309 and people seemed to be able to install those with only needed to add a couple new screw holes. Unfortunately, Grover seems to have discontinued the 309, but StewMac recently started stocking their apparent replacement, the 409. So I took the plunge, cracked out the tools, and documented the installation process with some pictures in the hopes that this will help the next person.

    First, when we are talking about replacement tuners for F-style mandolins, it is critically important to correctly identify and order "worm-over" or "worm-under" tuners. Eastman F-style mandolins use WORM UNDER tuners, meaning the tuner knob shaft connects to the gear below the axle for the tuning peg that extends through the headstock (this can be seen in the pictures below). This specific model of tuner is the Grover 409FVN.

    The first thing I noticed when I took them out of the packaging was that the tuner head shafts are noticeably shorter on the Grovers than on the stock Eastman tuners. The distance between the outside of the plate and the inside of the top-most tuner knobs on the stock Eastman tuners is about 27/32 of an inch.



    On the Grover, that shrinks to only 17/32 of an inch.



    This didn't turn out to be an issue with the Eastman headstock, but you should definitely check the spacing on any mandolin that you may consider putting these tuners on as headstock sizes may vary.

    Taking the Eastman tuners off is as simple as removing the five screws and pulling the tuners straight out of the back of the headstock.

    The Grover tuners slide right in. The tuner peg holes are perfectly lined up and spaced. No issues! In the below picture, the tuners on the left are the Eastmans, the tuners on the rights are the Grovers. Note the difference in knob shaft length. The Grovers clear the headstock, but the knobs are a fair bit closer than the stock Eastmans.



    How do they fit up on top of the headstock? Really well. The Eastman bushings were firmly entrenched in the wood and did not want to be budged. I had a bad experience last year replacing tuners on my tenor banjo where I damaged the front of the headstock by forcibly removing stuck bushings, so I let these ones stay put. I checked the Grover bushings on the Grover tuners, and they did not seem to provide a tighter fit than the stock Eastman ones, so I didn't see any need to remove the Eastman bushings.



    Time to screw them in.

    Second major difference that I noticed between the Eastman tuners and the Grover tuners is that the screws that attach the Eastman tuners are significantly longer than the screws that come with the Grovers. (Eastman on left, Grover on right)



    As you can maybe see on the above picture of the back of the headstock, both tuners use 5 screws. The screw holes on 3 out of the 5 are identically placed. Specifically, the middle three. The outside 2 screw holes are too narrow for Grover tuners. Given that the existing middle three holes were going to be deeper than the Grover screws, I opted to re-use the longer Eastman screws for those three holes. They fit well.

    The outside two screw holes needed new pilot holes. Time to crack out the power tools!



    I used a 1/16 bit (don't use that one too often, now do I!) and CAREFULLY and SLOWLY drilled shallow pilot holes. (I had a bad experience this summer when replacing tenor banjo tuners on a friend's instrument. I went a little fast with the drill and cracked the headstock. I was able to fix it all up in the end, but it was a learning experience about how gently we should mix power tools and acoustic instruments).

    Pilot holes being drilled, I used the shorter Grover screws for the outside screw holes. Went in like a charm.



    One side done! Just do all of those same things again on the other side and, voila, you're done!



    The tuners turn very smoothly. I will post more of a first-hand use review in a few weeks after I get a chance to use them more, but initial impressions are very favorable. The increased ratio is noticeable and much appreciated.

    One thing to note is that some people with meatier fingers may find that they get pinched between the knobs and the headstock due to the shorter shaft length on the Grovers. I have medium sized hands and fingers, so it's not too bad for me, but I thought it was worth noting for our companions with larger hands.



    I hope this was helpful!
    Eastman MD515 mandolin
    Gretsch G9310 mandolin
    Eastman MDO305E-SB octave mandolin
    Eastman E20om guitar
    Vega Little Wonder tenor banjo
    Epiphone El Capitan acoustic bass

  2. The Following 6 Users Say Thank You to Mando Esq For This Useful Post:


  3. #2
    harvester of clams Bill McCall's Avatar
    Join Date
    Feb 2014
    Location
    Forest Grove, Oregon
    Posts
    2,775

    Default Re: Grover 409 Tuner Installation Guide for Eastman F-style Mando

    Nice job.

    I always use Vix bits to drill pilot holes. It’s easy to get one hole that wanders and that messes up the finished appearance.
    Not all the clams are at the beach

    Arrow Manouche
    Arrow Jazzbo
    Arrow G
    Clark 2 point
    Gibson F5L
    Gibson A-4
    Ratliff CountryBoy A

  4. The following members say thank you to Bill McCall for this post:

    robw95 

  5. #3
    Registered User BillWilliams's Avatar
    Join Date
    Sep 2022
    Location
    Barreiro, Portugal
    Posts
    155

    Default Re: Grover 409 Tuner Installation Guide for Eastman F-style Mando

    Very helpful thanks.
    Sounds like an excellent Christmas present. I also have a 515 and I'm now thinking
    I know what to hint before my next birthday.

  6. #4
    Moderator MikeEdgerton's Avatar
    Join Date
    Mar 2007
    Location
    Howell, NJ
    Posts
    26,874

    Default Re: Grover 409 Tuner Installation Guide for Eastman F-style Mando

    Your original tuners were Schallers. Thanks for posting this.
    "It's comparable to playing a cheese slicer."
    --M. Stillion

    "Bargain instruments are no bargains if you can't play them"
    --J. Garber

  7. The following members say thank you to MikeEdgerton for this post:


  8. #5
    Registered User Mando Esq's Avatar
    Join Date
    Sep 2022
    Location
    New Hampshire
    Posts
    105

    Default Re: Grover 409 Tuner Installation Guide for Eastman F-style Mando

    Update:

    Four months (and many hours of playing) later, I remained quite impressed with the Grover tuners. They hold tune well, work just as smoothly as the day I bought them, and I love the higher tuning ratio.

    Unfortunately, one of screws that holds a tuner button on fell off and disappeared recently.



    I contacted Grover customer service directly and asked them about a replacement. Fortunately, Grover immediately responded and agreed to send me a new screw for free.

    I got the package in the mail and to my surprise they included eight new screws and a personalized note.



    All in all, I am quite impressed with the Grover product and their customer service.
    Eastman MD515 mandolin
    Gretsch G9310 mandolin
    Eastman MDO305E-SB octave mandolin
    Eastman E20om guitar
    Vega Little Wonder tenor banjo
    Epiphone El Capitan acoustic bass

  9. The following members say thank you to Mando Esq for this post:


Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •