New Member

Talk about musical instrument construction, setup and repair.

Moderators: kiwigeo, Jeremy D

Post Reply
Bwalker15
Gidgee
Posts: 6
Joined: Sat Aug 14, 2021 3:27 pm

New Member

Post by Bwalker15 » Tue Aug 31, 2021 3:48 pm

Hi everyone,
I just want to introduce myself, just joined the forum a week or so ago. I'm a retired Engineer who now has a guitar building hobby.
I built a guitar with the Australian Guitar Making School down in Hobart in 2015 and ever since I have been wanting to make another but up until now I've not had a suitable space to do it in. But recently I've finished building "the shed" and managed to fill it up with a few woodworking toys and I'm into my first guitar build. It is a mix between the plans/instructions in Jonathan Kinkead's book and my own Maton CW80 acoustic guitar. Progress has been slow since every step of the journey seems to require at least 1 new tool or jig but it's a very interesting and rewarding journey.
An issue that I've really found challenging is humidity. Today, for instance, in Dapto NSW where I'm located, temp is 26C & RH is about 40% (depending on which meter I believe but I think this is a fairly accurate reading). Under these conditions I am now seeing some lovely guitar sides which I have stored, starting to curl up across the short side. Can anyone advise on how best to cope with this or do I just have to live with it and work on the wood when weather conditions are ok.
Anyway, many thanks to all who share their expertise and hard won knowledge on this site, it is very much appreciated.
Cheers,
Colin

User avatar
WJ Guitars
Blackwood
Posts: 372
Joined: Thu Jan 26, 2017 4:28 pm
Location: Sutherland NSW
Contact:

Re: New Member

Post by WJ Guitars » Tue Aug 31, 2021 4:24 pm

Welcome Colin to the forum.

When I was investigating and planning to build guitars I had no understanding regarding humidity issues. Fortunately, about 10 years ago I met Gerald Gilet at his Guitar building factory at Botany and when I told him that I was setting up my own workshop the first thing he strongly recommended was to install a humidify that was set around 43%. I gratefully received his advise and purchase a humidify, cost around $650.00 (Brand 'Moisture Cure', Model WDH-735EA 30R).

To prevent the curly issues it is important to have the humidity under control while preparing the top and back bracing until the box is closed. If you decide to install a humidify I would recommend running an outlet pipe from the humidify to the outside though your shed wall to drain the water moisture and avoid having to emptying the storage compartment.

Wayne

User avatar
ozziebluesman
Blackwood
Posts: 1529
Joined: Wed Oct 10, 2007 9:12 am
Location: Townsville
Contact:

Re: New Member

Post by ozziebluesman » Tue Aug 31, 2021 4:35 pm

G'day Colin and welcome to the forum.

I live in Townsville and have the opposite issue with humidity to you.
Up here 60% is ok as long as the instrument is going to live here other wise, I use a dry box. The box is big enough to lay a dready out in with cam clamps on for example if you are going to close the box on a build. I have my shop with an aircon and can take the humidity down to 45%, do my work and then put the project in the dry box at 45% and turn off the aircon. The box has a globe socket in the bottom with a dimmer switch wired in the circuit. I use a fairly low watt globe around 40 watt and then I can adjust the globe up and down which adjusts the heat inside the box. There is an intake air hole down the bottom of the box and a small computer fan up the top but a small hole usually works well as an exhaust and the fan is really an overkill. I also store my wood for the next two builds in there as I like to try and get two builds in a year. I have a shelf in the box and keep the keep the future build woods under the shelf. On top of the shelf I can then store stuff I am working on presently.

I have seen many use an old single wooden gents wardrobe with a globe installed down the bottom and that work well. I made a mdf box with a sealed lid.
The other method is a humidifier.
Hope to see your builds on the forum.
Cheers
Alan
"Play to express, not to impress"

Alan Hamley

http://www.hamleyfineguitars.com/

User avatar
TallDad71
Blackwood
Posts: 190
Joined: Thu Jan 19, 2017 6:20 am
Contact:

Re: New Member

Post by TallDad71 » Tue Aug 31, 2021 5:36 pm

Humidity is the invisible enemy!
The goal is to match the Relative Humidity in your workshop to the RH in the room where the instrument will live.

The ideal is to store your timber in the room where the guitar will spend its days. Takes the wood out when it is being worked on and bring it back to settle at the correct humidity in between jobs.

Depending on where you live you’ll need to invest in a humidifier or dehumidifier for the shop. Over time you can get a sense, using meters, of how closely you can keep the two rooms matched. If the match is close then that saves a lot of faff with moving materials.
Alan
Peregrine Guitars

User avatar
kiwigeo
Admin
Posts: 10580
Joined: Sat Sep 29, 2007 5:57 pm
Location: Adelaide, Sth Australia

Re: New Member

Post by kiwigeo » Tue Aug 31, 2021 6:01 pm

My approach to humidity has always been to maintain shop humidity at a level equal to or lower than that in which the guitar will be eventually living. A guitar taking on a bit of moisture is better than a guitar that is drying out.
Martin

Bwalker15
Gidgee
Posts: 6
Joined: Sat Aug 14, 2021 3:27 pm

Re: New Member

Post by Bwalker15 » Wed Sep 01, 2021 11:17 am

Thanks for the detailed advice everybody.
I'm starting to get a bit of an understanding of the RH problem.
Firstly I don't think I'm storing my wood very well, at the moment I have had layers of sides and front/back sitting on top of each other & so, of course, the top surface of the top layer dries out the quickest & so curling takes place. I have now stored each layer on packers so there is a gap for air movement which will hopefully result in more uniform moisture content during temp changes.
Secondly, I should try to store new timber at constant lowish RH conditions (approx. 40%) to allow moisture stabilisation for a period prior to using & then keep it at this condition during manufacture (especially during bracing front & back) & up until boxing the guitar.
Up until now I have assumed that to achieve this I would need to humidify the air during the day, especially during summer but now I realise that during nighttime when the temp drops the RH can rise substantially & so the timber is always taking in/losing moisture when stored under these conditions & some dehumidifying is also necessary.
I think the humidity stable storage cupboard/box sounds like a good way to go & I will now look at that.
Thanks again,
Colin

Bruce McC
Blackwood
Posts: 395
Joined: Thu Apr 07, 2011 1:29 pm
Location: Canberra ACT Australia

Re: New Member

Post by Bruce McC » Wed Sep 01, 2021 6:57 pm

Hi Colin welcome to the forum.
Are your sides well quarter sawn? If not they will tend to cup in storage, particularly
if they are not separated or "stickered". Sides that are not well quartered also have
a tendency to ripple when bending. See the recent post by Robbie O'Brien on this forum.
Bruce Mc.

Bwalker15
Gidgee
Posts: 6
Joined: Sat Aug 14, 2021 3:27 pm

Re: New Member

Post by Bwalker15 » Fri Sep 03, 2021 11:40 am

Thanks for that Bruce,
further to your post, I looked at a video from the Woodworking Guild of America on this subject and then studied my timber closely & found the growth lines running through it at about a 30 degree angle rather than 90 degrees. According to WGA this means my timber is Rift sawn rather than QS. I assume that most guitar timbers vary between QS and RS with the most expensive being QS.
Colin

Post Reply

Who is online

Users browsing this forum: No registered users and 35 guests