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young-lecky
12-01-2013, 02:08 AM
I've decided to take the step of making my own ukulele.

I'm a carpenter by trade so I'm used to working with wood and my hands, although I've never made an instrument before.

I don't want to buy or make the type of bender I see a lot of on here which includes the heat blanket, instead I'm going to use a metal pipe to heat and bend the wood around it. (I've seen it done on the internet a few times and thought it would be better than steaming)

My question is, ruffly what temperature would the pipe need to be so it heats the wood enough to make it bend but not char it?

I know every wood is different but I'm looking for a ball park figure.

Thanks :)

bigphil
12-01-2013, 03:45 AM
I can't help you with the actual temperature, but I think you'll find that if the pipe isn't hot enough to char the wood then it will also not be hot enough to bend it. You must achieve a balance in your technique, getting it hot enough to bend without scorching it. That is part of the skill required to use this method. Even folks who have lots of experience will occasionally scorch wood on a pipe. Practice on scrap before attempting your actual instrument sides.

I recently started my first uke build but I made a simple side bender that uses light bulbs instead of a heat blanket, it has a lot lower learning curve to obtain excellent results. You can find pictures of my bender in my build thread.

Rob-C
12-01-2013, 04:45 AM
You should make up a bunch of practice wood to experiment with - bending wood by hand is a very tactile process and you need to develop a "feel" for how the wood is reacting. I'd recommend maple as an easy wood to learn with.

I use a gardener's water-spray bottle to dampen the wood before bending. You can also use this spray to judge how hot your bending pipe is - squirt some water on the pipe and it should flash into steam instantly, rather than wetting the pipe and boiling away gradually (too cool) or blast into steam violently (too hot).

You need to get a bit of experience with it - it does take some skill.

Rob.

jcalkin
12-01-2013, 05:04 AM
300 degrees is plenty in any sort of bender. 375 degrees seems to be a favorite temp for hot pipes. But the above advice is excellent. If you're going to go low tech you might as well go as low as possible. Stew-Mac and LMI sell contact thermometers, but you really don't need one. They really aren't practical unless your pipe is electrically heated and will hold its temp well.

young-lecky
12-01-2013, 05:14 AM
Thanks for the help :)

Phil, I take it you work/have a hobbie with woodwork projects that require a lot of detail?

The quality of your work is amazing. I'll just say now that mine will be nowhere near as good as that come the end lol.

As this is my 1st ukulele build I don't have many of the required power tools so most stuff will have to be done by hand.

I will be looking at your thread through out my build to make sure I'm doing it all middling right :P

Timbuck
12-01-2013, 07:08 AM
I find 290 F is about just right on dry Mahogany 315 F and it starts to scorch if you don't move it about..but my bending set up is shop made and the temp gauge may be a bit out of calibration :)

Moore Bettah Ukuleles
12-01-2013, 07:14 AM
You can get the pipe as hot as you want if you lay a wet, folded hand towel over the pipe. Keep spraying the towel with water as it evaporates.

Ken, I'm sure you mean Fahrenheit, not Celsius. I don't really think you want the pipe glowing red! ;)

Timbuck
12-01-2013, 07:34 AM
Ken, I'm sure you mean Fahrenheit, not Celsius. I don't really think you want the pipe glowing red! ;)

Yes! you are correct Chuck..So I edited my C's into F's . :o.

bigphil
12-01-2013, 04:26 PM
Thanks for the help :)

Phil, I take it you work/have a hobbie with woodwork projects that require a lot of detail?

The quality of your work is amazing. I'll just say now that mine will be nowhere near as good as that come the end lol.

As this is my 1st ukulele build I don't have many of the required power tools so most stuff will have to be done by hand.

I will be looking at your thread through out my build to make sure I'm doing it all middling right :P

I have build some dulcimers in the past, I also do N scale model trains (which are very small) and RC model planes. Working with any wood has some overlap no matter what the end product turns out to be. I still have a lot to learn about ukulele building, but I am fussy and try to do the best I think I can on everything I try. The uke build has been fun so far and an enlightening experience. When I see the masterpieces turned out by a great many of the builders here I am humbled though. Thanks for your comments!

ksquine
12-02-2013, 07:47 AM
I don't know how hot my pipe gets....I use a spray bottle to check it. The water from one spray evaporates in about 1 second when its good to go. If it drips off the bottom of the pipe....too cold. If it instantly vaporizes or drops bounce off....too hot.

FYI, this is a cleaning solution type spray bottle from Home Depot. Very highly calibrated and scientific method

Liam Ryan
12-02-2013, 08:23 AM
That's exactly how I do it. A little sizzle, then evaporation rtather than an instant "poof" of steam.

young-lecky
12-03-2013, 07:05 AM
thanks for everything folks :)

Another question... i received my pieces of wood today, and one of the back pieces has about 2mm of a camber in it :( whats the best way to take it out, and that will keep it out?