How to Shim a Bass Guitar Neck.

[@MRegah]

awesome, that was very helpful! I'll have a look at more of your videos! one remark: the calculations could have been much simpler: (intended hight change at bridge)*((length of pocket)/(distance end of pocket to bridge)). No angles needed. That's because the hight is proportional to the length of the base in a right triangle : )

[@RobMods]

OMG, you sir are a genius! I've been doing it this way with trig for years. But you are absolutely right. Thanks for your comment!...

[@MRegah]

Rob Mods. Haha, glad I could return a favour : ) Greetings from Berlin.

[@Homs86]

yooo thx mate, was thinking about an easier way too - but 3 points in maths....

[@aydencamdyn5152]

instablaster.

[@nathansweeneymusic]

I know I'm years late to this but can someone please show me this formula relative to robs measurements? I dropped out of year 10 😢😅

[@mattliebenau9083]

This is it! The moment your teachers warned you about when trigonometry could save your life! Seriously, very exacting and meticulous work. Good job.

[@danielirvine7468]

Man you’re a pro !! I love watching these kind of vids

[@beefyjoe]

my eyes glazed over as i experienced ptsd when high school math appeared 🤣

[@peadookie]

WAIT! A _pro_ player playing a squire?!?!? 🤯😂 Gotta say - I’ve got a squire Classic vibe P bass sitting directly next to a couple boutiques that are each worth more than moving the decimal on the squire 😂 A great setup like this makes a massive difference. This is the bass every beginner (and pro!) deserves!

[@davidglass6027]

I have to shim a fellow player’s pseudo Jazz bass for the exact same reason you needed to shim the P-style bass in your video. Your step by step instruction will be very helpful indeed; thanks Rob!

[@sarahdop4071]

You don't need to know the angle, you can work out the intermediate height (h) by similar triangles - x/96 = 2.5/359, thus h = 96 x 2.5/359 = 0.67mm

[@iggynub]

Could someone explain this more? Its very interesting. I've tried looking up similar triangles but have lost how it connects to the bass.

[@joepalooka2145]

Really nice work, Rob! I recently had to do the same with a Fender Custom Shop Telecaster. I just could not adjust the bridge properly. The problem was exactly the same as your video. I installed a shim of about the same thickness as yours, but I did not taper it. It plays perfectly now. This is a much more common problem in all electric guitars than people realize. The reason is that bodies and necks are mass produced in huge volumes. The neck pocket is cut with CNC. Then they're sanded, then they are painted. Necks are installed that are also mass produced on a production line. The thickness varies between parts, shrinkage happens, add sanding and paint thickness and wood quality----- it's all about quality control. You have to do the fine tuning yourself.

[@perrysar5954]

Thanks Rob,you're a Pro! Im a big fan of the 70s Jazz bass that had a slot in the neck plate to adjust the angle with an allen key.

[@DougHinVA]

Regular electric guitars usually need a shim at the rear of the neck pocket. I find a standard business card marked to match the neck heel curve means 1/32" at fret 12 lower string gap (fret top to string bottom). If 2 are needed, make a bottom shim double the length of the rear one (to provide a tapered shim). I also replace the standard offshore 10mm length saddle adjustment Allen screws with 8mm ones to lower the saddle heights and allow screw tops NOT to chafe the right hand when playing.... and eliminate shimming sometimes!

[@AnthonyONeillandtheMurde-xc2di]

Thanks for this - I managed to get the action down from something you could comfortably fly a 747 under to just a few mm.

[@peterjosvai9804]

wow, totally brilliant! the way it has to be done :) the way it can only be done with good results -- I'm convinced of that having seen this video... love the calculation method... and love the intermediate shim idea!!!!!!! way-way better than attempting to create a wedge shape, angled shim, which I didn't dare to try... really like the sanding part... including the pencil trick... and then the small LED light trick :) ("tricks" like these, I guess, can mean a fail / success difference) one note for all of us: digital calipers like this only have an accuracy of 0.2mm now I can shim my beloved P-bass!! :) thank you!

[@RobMods]

Thanks Peter. I'm glad you liked my video. If you've ever reset the dovetail on an acoustic neck, you have to make calculations like this to get the angle as close as possible before you go to all that trouble.

[@bassboy000]

Nice work as usual Rob.

[@johnnyb3376]

Thank you for this very useful and thorough instructions. I have this exact problem with my Fender P-bass . Great video !

[@JamesZarubin_64]

Always enjoy your videos. I am designing a circuit after watching your other rotary switch video. I don't have a neck problem so far...which is good.

[@luke.gill49]

Love the trig for precession... eyo! Thanks for the video

[@pabloortega5872]

Great video

[@burningkarma]

Didn't have much laying around other than a piece of card stock. 1 shim wasn't enough, made it 2 and now we're good. Amazing what so little can do when adjusting the neck angle.

[@ant_yep]

Very fine detail. I really liked 👍 Beautiful job

[@gardenofnightmare]

You're a genius!

[@sarahdop4071]

Great video - proper job!

[@robwillox7033]

Just discovered your video shimming up a horrible 82 Hamer "Slammer" Korean made guitar with the merest of materials to actually call it a guitar. I'll have to review the trig or learn how Mr. Hager's method works. Thanks so much.

[@Belman5]

Nice intro! And great video as usual. I'm going to try this on one of my basses which has a similar problem.

[@RobMods]

Cheers mate!

[@nanimonada9860]

You didn't place the shim over the screw holes. . . . What a great idea!

[@warbirdnut9269]

Great video. Any thoughts about using the shims made by StewMac (besides being expensive?). Also wouldn't it be better to create a shim that fills the neck pocket? Seems like that would distribute the pressure across the entire neck pocket. Also with more surface area the neck makes better contact with the body (which improves the sound?).

[@martin.ilek_bassplayer]

Great video. Thank You!

[@Bob-Whiting]

Stop talking all that Maths Witchcraft! Seriously tho, excellent tutorial. Thanks a million!

[@basspoobag]

Great attention to detail Rob, would be happy to have my bass in your hands. Can you speak more as to why you chose to use two pieces of veneer to make the shim rather than a single piece on the bridge side of the neck pocket. Perhaps due to the uneven surface in the pocket / easier than trying to level the pocket? Great work as usual.

[@RobMods]

Ha ha, well, it's partly because it just feels right to do it. But I guess, it offers another mating surface with the neck heel. It would otherwise be an air gap between the back edge of the pocket and the shim. Having the main shim go back to the screws, and also having that middle shim means the heel will stop when you torque up the screws instead of possibly flexing slightly, which may lead to the screws loosening over time. You could also make a shim that covers the whole neck pocket, but this will need more sanding and IMHO, is a bit over-kill. This neck pocket was more uneven than usual, and needed a bit more sanding. It usually is just a quick kiss with the 120 grit to level it up.... Cheers!

[@marksanders8066]

The old timers like me just used a guitar pick for a shim works great.

[@RussellCatchpole]

@Rob Mods. Wow great video 👍 I need to do this on my Dean Edge fretless 6. Can you advise me what should be the string clearance at the bridge end of the neck for the low B and the high C please? It's currently 8mm at the B and 3.5mm at the C, which is as low as I can get it by adjusting the bridge right own and truss rods, but seems way too high. TIA.

[@ATMcrespo]

When shimming is it important to make sure to eliminate any air or empty space between neck and body to retain the sustain?

[@RobMods]

Good question. Some luthiers will create a full tapered shim that covers the entire pocket, but I've never bothered. Once the neck is pulled down to three contact points, plus shimmed in the sides if needed, then it is fine IME. Also make sure the screws are actually pulling the joint together. Often manufactures just drive the screws straight in. The holes in the body will often be too small, and the screw will jam and stop. You need the screw to spin in the body so it draws the heel down firmly. I will usually also put a small smear of dry lube or lanoline grease on the threads so I can feel it better as I torque up the screws. This will also protect the threads from rusting, especially in tannic timbers. Cheers.

[@donjoseph73]

Also why didn’t you just make a full pocket tapers neck shim?

[@neon_one]

I just noticed there's a piece of poorly cut sandpaper stuck under my bass neck... not sure if ibanez did that or what. it def wasn't me

[@smalldog221]

is there a factory spec for the height of the fretboard on the neck for a base starting point?

[@jazzman1954]

I've been playing a Fender Jazz for decades with very low bridge and exposed grub screws. It's never been a problem. Why bother?

[@neon_one]

I'm trying a stack of plain paper cuts. mostly because I had some I was going to throw out. I'll probably forget to report how it went

[@thadcox5298]

You did

[@WardSeward]

Could be a US vs UK thing but... wouldn't it be geometry? Not Trig? However, great video. Thanks!

[@RobMods]

Quite possibly. In Australia, we use UK english and spelling mostly.

[@cartematt]

Have you tried brass for shims?

[@Bass.Player]

Very good! I could see how uneven that neck pocket was after you finished sanding the shims...

[@llTheGoose]

Have just picked up a Sterling Ray4 about 4 months ago, and no matter what I do in regards to saddles/ bridge height, I can't seem to clear some fret buzz on most of the upper neck. Would a shim on the opposite end of the neck cut-out help resolve this? Cheers.

[@RobMods]

I doubt shimming will help for this. Make sure the relief is set correctly, then check the nut slots, then adjust the saddle heights. If the saddles run out of adjustment, then this is when you need a shim. Buzzing usually means the trussrod is out of adjustment, the action is too low, the frets need leveling (or reseating), or the neck has warped... Or, more likely, some combo of these.

[@llTheGoose]

@@RobMods Thank you for the response. Will have a look and see if I can't get it to work. Reason for thinking it might need a shim is that with the necl relieved to its current point, the feet board is bowing backwards slightly, sort of a banana shape. My thought process is to level the bolt area, will help alleviate this.

[@gilberterazo732]

How much does it cost to get a shim installed?

[@nothingheretowatch7371]

Shim alone is 10$

[@MrKenstar2]

Neck isn’t making full contact with the body which is a no no

[@danieldupuys2002]

I prefer a flat neck pocket, if problems whith too longs screws, cut the screws!

[@TheBigMclargehuge]

Oh yeah sure I'm definitely going to do all that math and sanding in order to achieve the most imperceptible improvement in playability over using a bit of credit card.

[@kevmac1230]

This guy only reminds me of what a hack I am

[@gasparepellecchia]

4:15 => 5:40 😂😂😂😂

[@MagratheaLegend]

Way to complicated for me, but great job anyway!

[@erockscott1184]

I'd rather experiment lol...math sucks

[@RobMods]

Ha ha. Fair enough. After making this video, I realised there's a simpler way to work it out. I'll make a Quick Tech update next time I get a shim to do...