Crack in the back. Any advice?

[MandoNina]

So my beautiful "first bought" has started to show signs of her old age and my tropical location. There are some small but ominous cracks building up in the back and it seems they wants to go from one end to another if given the chance.

Any advice on what I can do? There are no decent mandolin luthiers close by unfortunately.


Harder than expected to get a good picture of the crack

[billhay4]

Can we get a little more information about the instrument? What is the wood? How old is it? What kind of finish is on the instrument?
Basically, you'll have to stop the cracking from getting worse and stabilize what is there. Gluing and cleating the crack is the normal way to do this.
Frets.com has a number of pages on repairing cracks. So do other sites.
You can do this yourself UNLESS the cracks get so bad that special clamping setups are needed.
Good luck.
Bill

[Paul Busman]

I can't tell from the pictures-- does that crack go all the way through?

[MandoNina]

It's a German Hofner 545 from the 50's or 60's. I bought this instrument used and I cant say for sure if it's original or not, but assuming it is, this is the description of the instrument that I have found online:

Symmetrical tear drop-style body, arched mahogany top, arched mahogany back, mahogany sides, two bound cat's-eye soundholes, wide top and back binding, mahogany neck, 17-fret rosewood fingerboard with large block inlays, slotted elaborate headstock with four-per-side open-style tuners, rosewood bridge, trapeze tailpiece, pearloid pickguard, in Natural finish.

The cracks has not gone all the way through. Far from it actually. They seem merely superficial for now, but they weren't there 3 months ago so I can only imagine how they will be in 3 months from now if nothing is done.

[pops1]

It may be finish coming off, if the crack doesn't go thru now. If you can move one side from the other it is thru. With Mahogany it is common to find cracks with age. If they are hairline cracks, which these may be should the go thru, I will make a thin glue and Mahogany dust and rub it into the crack with my finger. Wipe all residue off with a damp cloth immediately. This has worked good for me to solidify the crack, I don't worry about cleats, and have had no problem. If they don't go thru , don't worry about them and play, play, play.

[multidon]

Mahogany? It looks more like rosewood to me. And most likely rosewood veneer, as you can see much lighter wood through the “crack”. I don’t believe the cracks will ever go through. Notice how the specs don’t say solid mahogany? I am 99 percent certain your instrument is laminated. Cleating would not be possible, there would be nothing on the other side to cleat. Cross grain laminations prevent true cracks, what you see is just in the first layer of laminate.

If it were mine I would try to find a furniture touch up pen of the closest color, just touch them up so they aren’t so obvious, and move on. Your damage is cosmetic only, not structural. And frankly, these don’t get a lot of interest from collectors so while you wouldn’t do that to a more valuable instrument, on this one it’s perfectly acceptable, IMO.

[Paul Busman]

I'm thinking that a drop of water on the crack would wick all the way through a full thickness crack for diagnosis purposes.
If it's just a finish flaw, I'd leave it alone if it were mine. Any repair would probably make it look worse. I've never tried this, but maybe some beeswax melted and dripped onto the crack, excess scraped/wiped off would make it less obvious. You could pretty safely scrape with a plastic putty knife or even a credit card.

[John Kelly]

I too think as Don does here, that it is rosewood rather than mahogany, and most likely a veneer over a ply (laminated) back. The specs do not mention solid woods, and generally manufacturers will tell you where they have used solid woods - usually for the soundboards. If it is laminated there should not be a problem of the crack going all the way through. Try a touch-up wax crayon (from furniture restorer) to conceal the damage, or leave it alone if you are not bothered by how it looks.

[MandoNina]

Thanks guys!

I suspect your right. The few Hofner 545's I've seen have all had some kind of Hofner marking on the headstock which mine doesn't so it's probably not original. And it is likely that it is rosewood and not mahogeny.

Not bothered at all by how it looks.
I don't mind wrinkles on my instruments. Especially not if I was there as they happened

And I only payed $60 for it, so having someone just look at it would cost me around what the mandolin did, but I love it and wouldn't let it go for ten times that now.

[GrooverMcTube]

I seem to recall seeing a video on StewMac where he used #10 cyanoacrylate to fix a chip on a guitar. The #10 is super thin and can work its way into small cracks by capillary action. Might work in your application if you mask it off carefully. Here's a link to the video where he touches up after the repair. You might need to modify the method on an arched back and put the tape on the mando rather than the razor blade. Of course there is always the possibility you could bugger up the finish in the process of trying to fix the crack.

Or, if it is just a finish crack maybe it's just mojo and you should wear it with pride?

[multidon]

Just because it doesn’t say Hofner on the headstock doesn’t mean it’s not a Hofner. They were, and are, a huge instrument factory who made instruments to order as well as under their own name. Yours was probably made to be a house brand bynthem for some wholesaler or retailer.

Rosewood veneer over plainer laminated wood is a hugely common instrument construction technique in Germany, Austria, and possibly other European countries. You see a lot of concert zithers made with similar materials.

[pops1]

I didn't look at the pic before talking about Mahogany, my bad, but it is rosewood. Laminate construction was used in this country back almost 100 years ago. I had a 1930 guitar that was laminated back and sides.

I wouldn't try the super glue, it can make quite a mess, prevent future gluing and not work as well as HHG or another wood glue.

[MandoNina]

Cheers!

Ok so I think I'll just keep an eye on it but leave it in peace for now. I really don't mind scars on my instruments. I actually think it makes them look better (provided the sound isn't affected) I was just worried it might grow into something big and expensive.

I love how my mandolin sounds and plays. Don't really care if it's original or not. I'll never sell it anyway.

But I did think that there would be some kind of mark somewhere if it was original... And wouldn't the 545's" Cat Eye Soundholes" make it too recognizable for them to pass it off to other companies for them to sell it as something else?
(as I wrote that last question, the fact that I know nothing about this prosess became clear to me (and probably you:))