Restoring an antique parlour guitar part 22: Flattening the top

[@Mick_Harrison]

This is a great series, I could spend all day watching, infact I have spent the whole day watching!

[@steveharris2589]

Nice work, I don't know why I have not found you before now. 🎸👍🏼😊

[@jholmessiedle]

I am enjoying taking the journey with you!

[@lalainaichane319]

You did an awesome job :) Subscribed!

[@robertkibbler1564]

Snap! Susan, I have just done a very similar repair on an oldish no name acoustic guitar I bought from a charity shop just to play around with. Even down to the little chip, but mine was below the bridge. I glued the loose fibres with tight bond and clamped the area between two Perspex shaped cauls one where the bridge plate was removed ,one the same footprint as the removed bridge. After removing cauls the area is flat and smooth. I was thinking of roughing it up with sandpaper before regluing the bridge,. I experimented trying to glue two pieces of wood previously coated with titebond and clamped between Perspex together . When I glued the two glued surfaces together with more titebond and let dry overnight I tried to separate them twisting and pulling but they are glued fast. Try it yourself? Titebond doesn't stick to Perspex end leaves a glass type finished when removed.!

[@SusanGardener]

Which Titebond did you use? Titebond 1 breaks down with moisture - not sure if it needs heat too. The moisture of the wet glue may break down the glued surfaces and help the glue to glue bond. The accepted wisdom is that a glue to glue bond is weak compared to a glue to wood bond. I should point out that I still have a fair amount of wood showing on the wings, particularly after the sanding I've done to get the finish off - oops spoilers! :-)

[@StansburyStudiosInc]

Great video! Just a thought - the reason why a lot of older classical (nylon string) guitars have a soundboard that dips between the bridge and the soundhole and then bellies up between the bridge and the tailpiece is because of the twisting action that the tension of the strings impart to the bridge (and thus to the wood beneath the bridge, in this case the soundboard) over the space of time. I have several guitars from the 70's that all exhibit this slight bellying/dipping effect and have made my own inquires of the original luthiers, several of whom have confirmed that they originally built the guitars with flat soundboards.

[@SusanGardener]

+StansburyStudiosInc It's not just classical - my 70s 12 string does the same - it's a design flaw usually - not enough bracing for the tension. Having finished this guitar there's no sign of bellying yet :-)

[@Joe_Sant]

The axe is coming along nicely.. Great work.

[@Joe_Sant]

By the way, what do you think of the bench now you've used it for sometime?

[@SusanGardener]

+Stokie Joe Bushcraft It was a good purchase after I did the mods. It's not so easy to clamp stuff to the surface though, due to the lack of depth and the 15mm edge strip. I might invest in a dog-hole clamp, or I might glue some extra strips round the inside of the top so there's more to clamp to on the edge.

[@RandySchartiger]

Pretty sure the guitar needs properly humidified from inside the body and that sink that's not flat near the sound hole will fix itself, if it's that flat just behind the bridge it should be flat around the sound hole too, being that old and knowing how long it can take to get a dried out instrument to "maintain" humidity inside at the right level, I would bet on it. Wood can absorb humidity for a long time before it gets to the level of safety. :) Great video's I had to go back a bunch to get caught up once you hooked me lol cheers!

[@SusanGardener]

Are you in North America? I've just replied to Thomas Tommy on a similar point. I think we have different perspectives on humidity.

[@RandySchartiger]

Susan Gardener Yes WV state. I've seen Thomas Tommy in several comments and other channels but not sure how much he knows. Different perspectives is a good thing, it can help us all learn in the end. :) Love your videos!

[@santosbay]

HEllo Susan, I just like your videos . and have a tip for you. when you used a block of pine with that tape and super glue on the rose wood.. if you make the tape hot with a hair föhn it wil loss easily. also the masking tape that blue one. with the greetings from the netherlands.

[@scottreeves6932]

White glue [sold in the USA under the Elmer's brand] does not darken so much as yellow glue. Also the white glue and sawdust mixture may be thinned down with water and used to fill small gaps in place of CA glue.

[@Tom345guitar]

Love these videos. I think the spots on the top were from welding splatters.

[@michellek5789]

I am really enjoying this series. May I ask where you sourced that Spruce.

[@SusanGardener]

I got it from a local luthier supplies

[@robertkibbler1564]

Hi,again sue. On the bottle is says professional tight bond original wood glue. Mind you it's possibly over 18months old.....ps. The wood I glued together was pine,I suppose I should have tried rosewood like the bridge is made of!

[@6022]

15:28 - 22 episodes in, and you're just scratching the surface. :-D

[@alext9067]

Susan, I have a question about filling in the tearout and other voids. Is it possible that a liquid could be used that would travel down into the voids and solidify to form a smooth surface appropriate for gluing other pieces (the bridge) onto? I had used a marine product years ago which I think is still available. It soaks into the wood and hardens. It was similar to the low viscosity cyanoacrylate, but came in two parts and was available in larger quantities and is very strong.

[@SusanGardener]

+alex tworkowski Alex, you're talking about something which is used to stabilise wood, rather than simply fill it - to be used on difficult to process woods which might look great but be very weak, due to spalting or rotting, or simply due to their structure e.g. burl. The wood here just needed filling, but I wanted to keep the use of filler to a minimum, as gluing to filled wood isn't as strong, and the filler would change the acoustic properties of the wood - potentially dampening vibration.

[@TheCookofthehouse]

Don't worry about the cork trees. Here in Portugal is where you'll find the majority of the European Cork Trees. The demand of cork is increasing very quiqly and a Cork tree can only produce so much cork every nine years. so, prices are going up fast. A cork tree takes circa 80 years to become an adult tree. After that it decays fast and not many are known to to live longer than 120 years. Many end up dying long before reaching adulthood. We have a saying about the type of plantation you want on your farm: "Vineyards for me, olive trees for my children and corktrees for my grandchildren". A cork tree is not really a tree. it has to be guided for at least 20 years otherwise it will remain and grow close to the ground. Cork is actualy the peal of the tree and the wood is only "relatively"tight bundle of otherwise loose fibers. You can't use the wood of a cork tree for anything but to feed up a fireplace. people are now growing millions of new corktrees everywhere in Portugal. unfortunately cork shall only be available from these trees in a distant future (I don't know exactly how old a tree must be to allow extracting cork but never before it becomes, at least 30 years old and the first two productions are of a low quality product so, I estimate that a cork tree has to be at least 55 years before it starts producing a reasonable quantity of top quality cork. In its life a cork tree will produce cork five to six times only. Its an extraordinary natural product for hundreds of different aplications, including war tanks internal accoustic and temperature insulation. Your videos are very good and allow us to follow the whole restoration process. Thanks for all the usefull information you share.

[@SusanGardener]

+Mario Tulio Thank you. Very interesting

[@MrDunosan]

Susan where did you get this “old” spruce within the UK? thanks

[@thomastommy1192]

I agree with Randy. That guitar needs to be humanity. The wood has dryed out. that is why the braces has pulled away in the center. causing the bow at the bottom of the sound hole.

[@SusanGardener]

I've been monitoring humidity over the past year and in the UK it never varies between 60-70% all year round, at least in my house. The guitar may have been stored in damp conditions at some point, but I think most of the damage was caused by putting modern steel strings on it. Problems with guitars drying out is more of a continental American issue I think - we're surrounded by water here.

[@thomastommy1192]

Maybe you should put a gauge inside the guitar for a few days. Then see what the humidity is

[@SusanGardener]

+Thomas Tommy it was around 60% when I did that a few months ago

[@thomastommy1192]

+Susan Gardener OK, I am sorry. If I upset you. it must I have worked out for you.

[@aliciapoppe2194]

Does the potassium peragomate age wood filler also?

[@Sysiphistication]

Where did you get that little Lucite block you are sanding with? Did you have to cut it from a larger piece?

[@SusanGardener]

+Sysiphistication yes, I cut it from a sheet of 10mm acrylic I bought on eBay

[@Sysiphistication]

We seem to be on a parallel wavelength. I just did the same thing, but I opted for 19 mm, thinking that with my stubby thick fingers it might be easier to hold on to.

[@esa062]

I wonder how glues stick to PVA-dust filler. PVA doesn't stick to dry PVA, but the dust may make a big difference. That's something to consider.

[@SusanGardener]

I wonder too. I'll be scratching the surface to provide a key. It's not as critical a bond as the main section, but any extra bonding strength would be useful.

[@esa062]

Scratching doesn't help with PVA glue. It works by penetrating the material. If it can't do that, then it doesn't hold. Roughening the surface helps with surface bonding glues, like epoxy. The force comes mostly to the clean wood-wood joint, but the top flexes and I think the sides do have a role in distributing the twist to a wider area. I would test glue a piece of rosewood on a sanded filler surface just to avoid surprises.

[@SusanGardener]

+esa062 I might film a test of bonding strength on glued surfaces

[@tristanpopowski2516]

lighter fluid didn't dissolve the finish, it was most likely so thin that you rubbed it off. just my thoughts, do what you will with them.

[@carlrudd1858]

Next time dilute your Titebond by 50% with water. Not only will it smooth better, it won't dry so dark.