Credit card thickness?

Discussion in 'Hardware, Setup & Repair [BG]' started by ByF, Jun 28, 2009.

  1. ByF


    May 19, 2009
    Hi all,

    I often see "a credit card thickness" mentioned here as a goal for neck relief. I've even repeated it myself, because more people have credit cards than have feeler gages.

    But I started wondering, how thick is a credit card? Are they all the same? What kind of neck relief are we recommending when we say "a credit card thickness?"

    So I got out my dial caliper (I used to work as a QC inspector) and measured all the credit cards, grocery store club card, auto club card, Red Cross donor card, everything in my wallet. To my surprise, they ARE all the same, about .030 inch (.75 mm). That's slightly under 1/32 inch, for those of you with fractional rulers.

    But .030 inch is a LOT of relief! All of my basses play very well with about half that much relief. I have two feeler gages that I keep in the "everyday" bass case, .015" and .017", and I try for relief in that range. I just checked that bass with a credit card, and .030" would be way too much relief for me.

    One thing I have noticed is that some people suggest using the string as a straight-edge, fretting at the first and last frets. That works, but I've read that the truss rod really only acts on the free length of the neck, the part that isn't attached to the body. So I've always fretted at the 1st and 17th frets, because the 17th is the first fret on the body.

    I tried my Ibanez with a credit card, fretting at the 17th and then at the 24th, and a credit card was still too much either way.

    So, I've been walking around my house measuring things, looking for the perfect "standard" for neck relief.

    Business cards seems to be too thin, about .010", so one is too little, two is too much. The top off a box of Wheat Thins is close at about .018".

    I found a glossy post card that was perfect, right at .015". But the odds of you all having an advertising post card from the J&M Landscape company are small. I couldn't find any more postcards around to measure, but I'll keep looking.

    Sorry for such a long post on such a trivial subject, but I have always felt that instrument set-up is first a measurement job, THEN an adjustment job, and finally a tactile test-- does it feel right? I wonder about "de facto" standards like "a credit card thickness."

    So what do you guys use if you don't have feeler gages or some fancy tool from StewMac? Do you really use a credit card?

  2. Jazzdogg

    Jazzdogg Less barking, more wagging!

    Jul 29, 2006
    San Diego, CA
    Most of the professional woodworkers I know keep a deck of playing cards in the shop to shim dado sets for odd-size plywood, router fences for jointing, and so forth; IIRC, they're consistently 0.010" in thickness.
  3. Slowgypsy

    Slowgypsy 4 Fretless Strings

    Dec 12, 2006
    NY & MA
    Just something to consider.... a basic no-frills feeler gauge at my local auto parts store is $2.95. I have no idea why folks bother with anything other than the real thing....
  4. Jazzdogg

    Jazzdogg Less barking, more wagging!

    Jul 29, 2006
    San Diego, CA
    There are times when feeler gauges aren't as convenient as other "tools," and other times when there's no substitute. :)
  5. ByF


    May 19, 2009
    I agree, but from some of the questions on this site, I get the idea that some people have no more tools than the two allen keys that came with their bass. Some don't even have that.

    Not to change the subject, but I have formed the opinion that we world has come to be so dependent on software that some people have no idea how to use a real tool. If something goes wrong with a bass, the first action of many people is to post a question on a web site. And quite often, the first response is "Take it to a pro and pay the money to get it set up. You might screw something up."

    I think some people are afraid of using tools, because they have never needed to use them. Last year I went to my high school for a class reunion, and learned that the machine shop, wood shop, and auto shop have all been replaced with computer labs, teaching CAD design. No wonder I work with so many young engineers who can use Unigraphics, but have no idea how to handle a wrench or a caliper. Real hardware is foreign to them.

    radicaldreamers likes this.
  6. cassanova


    Sep 4, 2000
    That's basically all I have and all I've ever needed to do good setups on most basses

    Before I started doing my own setups I used to hear that a lot. The most common that I heard was "don't touch the truss rod because if you break the neck you'll be covered and they'll have to replace your neck, if you do it yourself you'll be out a neck."

    The reason I bought into that hype when I was younger was because I never did truss rod adjustments and thought I might muck something up. Doesn't take much brains to use an allen wrench but, if you don't know what you're doing it is easy to over tighten and what not.

    Through a recent experience that you know about, I am going to be purchasing some feeler gauges, though I still say that setting up a bass is all about how it feels in your hands and you don't need tools to determine how good something feels. However, due to the occasional problem child bass like the one I just had worked on, which has also been a rarity, only 2 in 23 years, I can also see some value in owning gauges.
  7. stflbn


    May 10, 2007
    I've used business cards, sand paper, and playing cards to shim bass neck pockets.

    Just depends what I have around and how much of a shim I want/need. Usually 'want' because the shim is to reach my personal preference.
  8. mongo2


    Feb 17, 2008
    Da Shaw
    For shimming I've used masking tape layered in a step-like pattern on the neck heel with excellent results.
  9. shackled


    Jun 25, 2009
    Western NY
    My new bass has no relief, and I've been slowly loosening the truss rod to eliminate fret noise.
    The frets still hold a business card...
  10. he is talking about them as relief guages, not as shim people. I don't use cards because they are bulky to hold as compared to the slim automotive feeler one. I bought one from autozone when I was in college to do the valve adjustment on my old CRX, and I still use it 10 years later.
  12. John Wentzien

    John Wentzien

    Jun 25, 2007
    Elberta, AL
    Artist:TC Electronic RH450 bass system (original test-pilot)
    If your frets are properly leveled...use a dollar bill for a feeler guage.
  13. ByF


    May 19, 2009
    A dollar bill is about .004 inch (~.1 mm). I couldn't play a bass with that little relief, and my frets are level. But then I like to dig in a bit.

  14. I would think a credit card thickness would be a bit too much. I've always heard "several business cards" not credit cards.
  15. unclejane

    unclejane Guest

    Jul 23, 2008
    Actually you can save a lot of time by reducing it to a) an adjustment job b) tactile test. Measuring doesn't really get you anywhere that (knowledgeable) adjustment to your own preferences doesn't already get you. No fancy tools are needed (unless you discover a problem).

    Here's my general method.

    - set action as low as it'll go so that the buzz is just less than objectionable at the heel (i.e. the last few positions).
    - set height of nut (with nut files from stewmac) so that action at 1st position is to your liking (in my case that's almost at the fingerboard).
    - check for buzz and action at all positions on the neck:
    -- if action feels high in middle, tighten truss rod (I suggest 1/8 turn increments). Check for buzz everywhere on neck. Repeat until you find one area of the neck with objectionable buzz. Back off until that buzzy area is just under an objectionable amount of buzz.
    -- if action is too low in the middle, or certain areas are too buzzy, loosen rod. Check for buzz. Repeat until buzziest spot is just under objectionable.

    - recheck action at heel.
    - repeat whole process as needed until it's right on the gnats a$$.

    If you can't get the action the way you want this way, then there may be a problem. On my L2000 I could never get the middle of the neck's action low enough without having to overtighten the rod. The neck had a slight "ski jump" in the middle that the truss rod couldn't quite null out. The fix was to sand down the fingerboard at the heel to make the whole thing overall flatter so I could get the action lower.

    Don't start measuring stuff, it'll just add unnecessary steps and won't make you go less bonkers trying to figure out a problem.

    Sighting down the neck or using a straightedge can help diagnose problems like a ski-jump or other imperfection in the fingerboard tho. It can also tell you right away what direction you need to go with the truss rod - if there's a big dip, you know you might have too much relief to start with. If it's got a back bow to it, you know the rod is probably already too tight.. etc.

  16. cassanova


    Sep 4, 2000
    This is pretty much how I've always done set ups and its been very good to me over the years.
  17. John Wentzien

    John Wentzien

    Jun 25, 2007
    Elberta, AL
    Artist:TC Electronic RH450 bass system (original test-pilot)
    If you have a "proper" fret level you can have the neck almost perfecty straight..No matter how aggressive you play..with very low action.
  18. Rick Auricchio

    Rick Auricchio Registered Bass Offender

    Ed, it may have been I who said "credit card." I misread the FAQ from the MusicMan site, which recommended a business card.

    Still, I agree that feeler gauges are the way to go.
  19. My rule of thumb has always been: Enough relief to let a single business card slide out.... but hold 2 in.
  20. ByF


    May 19, 2009
    Feeler gages are not "fancy tools." They cheap and available everywhere.

    Using proper tools will save you a lot of screwing around if there is a problem. Yes, if your truss rod needs a little tweak you can do it without making a measurement. You can use credit cards or business cards, or nothing at all. What ever works is fine.

    What if you're putting on a brand new neck and want to set it up to the factory spec? What if you've dressed the frets, replaced the nut, and put on a different gage of strings, and want to dial in the setup without a lot of wasted time? What if you're not working to your own preferences, but someone else's? I've done all these things, and I guarantee it was faster to use measuring tools than to do it by feel.

    I would suggest that have a few simple, basic measuring tools will make you more "knowledgeable" than you would be without them. And they don't come much simpler or more basic than feeler gages.