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I was just watching robert o'briens dvd and noticed that no temp control was used on the blanket to bend the sides. just a timer.....
one question i have is ..is it easy enough to use without a temp control

and because of the rubber blanket being made of rubber does that mean it doesn't burn your timber as much and that a temp control is not so critical??

I'm still trying to come to conclusions on the side bending...within my budget
I can afford a blanket or a bending iron but not blanket/timer/tempcontrol/
if i can do it with just a blanket i would go that way?

appreciate what info you guys can offer gratay38982.8088194444

Grant, I believe all you need to control the temp is a light dimmer from the hardware store. 12.00? I have seen the one on the lmi sight and I have the same dimmer on my wall switch. I personally use a veriac. May be overkill, but I Had it.

Mark

Yes, you can still make charcoal out of your wood with a blanket. You can do it without, but you're much better off and your wood and your shop will be safer if you use one.

Be sure you get a dimmer or other control with sufficient power handling capacity, somewhere around 800 - 1000 watts, depending on the blanket. Router speed controls work well, not too expensive. Check with John Hall.

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now known around here as Pat Foster
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http://www.patfosterguitars.com

Grant,
I had heard that the dimmers are not made for this type of wattage, but I'm no electrician. I use one blanket with a side bender, and no thermostat control neither. If you wrap the side in a wet paper towel, and use spring metal in a sandwich, you will have better luck. You can tell when the wood is ready to bend by just listening to the wood/steam sizzle. Wait about 5-10 seconds longer than the sound of sizzle, then just crank down. This should work fine.

I've toasted 2 different koa sides when using 2 blankets, so it can be done. I found that if I use 2 blankets, I soak the wood for 2 hours. It's really hard to toast a side with that much water in it. I also noticed, you can cook a little longer, and have less spring back with the side being soaked. Just my observation. I'm no expert, but just what I noticed. You should start with one blanket and test yourself. Good luck!
TracyLuthierSupplier38982.8314583333

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Tracy
http://www.luthiersuppliers.com

If you get a 2.5 Watt/sq inch blanket, you can use the cheap dimmer switches from Home Depot, as those are rated up to 600W. I'm guessing it takes a little longer to get up to full temp, but it'll still scorch wood if you're not careful, so it's plenty of heat for bending. And you can't afford to not have a timer... It's real cheap insurance against burning up a nice side set, or, more importantly, your shop/house.

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Jonathan Kendall, Siloam Springs AR

I found a 1000 watt dimmer at Home Depot.You can also find them on Ebay
http://cgi.ebay.com/Lutron-NT-1000-IV-Incandescent-Dimmer-10 00-Watts-NIB_W0QQitemZ200027877625QQihZ010QQcategoryZ20581QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem

Router speed controllers are about $15 USD on sale at Harbor Freight, in the USA. DO NOT use any contol if it's wattage rating is lower than your heating blanket is rated. THAT may overheat and cause problems. You're talking about a major potential for fire. 'specially if you distract easily

EDIT: Please don't downplay safety; remember there are people all over the world reading this, and some may be some young boys without wisdom. Because someone has not had a fire previously, doesn't mean it's safe practice. It's like drinking and driving. Set the safety bar higher and don't jeopardise someone else's safety cause you're too lazy, cheap, foolish, or cocky to take proper precautions. And if someone is that foolish, it wouldn't be wise to broadcast it here We don't want Lance's forum to be tarnished in any way

Rant over.


Terry Stowell38983.4065046296

Bottom line is, Just don't leave the blanket with,or without a timer or dimmer of any kind. Just don't leave it unattended and EVERYTHING WILL BE SAFE AND SOUND.

Hi Grant,

My opinion for all its worth...if cost is a major factor then how about a light bulb powered bender. See Jim Williams' book for a rough plan. Ive built one and can supply info on where to get the ceramic bulb holders (dont use plastic batten holders..theyll melt). A cheap timer can be used as the bulbs arent pulling as much current as a blanket. For temperature control I bought myself a roast thermometer and it pokes through a hole in the side of the bender. I dont use my bender that much preferring to do my bending by hand on an iron but it does work and it doesnt cost the earth.

Cheers

What Martin said, i built one with 3-200 watts bulbs and added the heat blanket after, the combination of both helps to keep the temperature steady on both sides of the wood, here's ma bender in operation, i have the thermometer that was supplied with the blanket by John Hall:





With the bulbs and the blanket it does get really hot!

cheers martin , that would be great if you could pass on the supplier info for the battons

and thanks for everyones input, I have been agonising over this part of the build.....

but I'm sure more agonising to come before the end or start for that matter of my first....
but preparation for the first and ease of future builds is important to get right initially

Serge that bender must put out some heat....are you building asbestos guitars???

[QUOTE=kiwigeo] Serge that bender must put out some heat....are you building asbestos guitars??? [/QUOTE]

no no, just cast iron!

Light bulbs work great, but compared to a blanket will not heat as even. I see no need to use two blankets, its overkill - with the wood right next to it, there wil be what ?? about a 2 degree difference from one side to the other - if that. too much heat wont do anything for you except potentially crack wood from drying it out. As far as the 2.5 taking longer to get to temp - its at bending temp in mine in about 2 minutes ... that too slow for you ??? You can do an EI rw side, on a form with tight waist and upper bout like a jumbo in about 7-8 minutes. Much longer than that and you are going too slow, or the temp is wrong.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Grant,

Check with John Hall to get a blanket with a router speed control to control temperature. This will work fine.
I always turn off the radio, phone etc. when bending sides and concentrate fully on the task at hand. Never leave a blanket and side unattended until you are sure that the blanket has been turned off and the plugged pulled from the wall. Safety first boys and girls!
Happy Bending

I once left a set of bindings in the bender for three days. There was a bad smell in the shop when I went back down there. It was cooked sycamore. Just lucky for me that I didn't start a fire. I believe it was right after that I installed a dimmer and timer setup. Now the timer cuts off the juice to the blanket after 10 minutes whether I am there or not. I always stay while things are cooking though, and I unplug the whole setup every time I leave the shop. Got lucky the first time, no need pressing my luck!

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Dave Rector
Rector Guitars

Thanks for the reminder guys!

[QUOTE=Serge Poirier] [QUOTE=kiwigeo] Serge that bender must put out some heat....are you building asbestos guitars??? [/QUOTE]

no no, just cast iron! [/QUOTE]

"As-best-os" he can!

(Which is very fine, indeed!)

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http://www.presnallguitars.com

are the 2.5watt/sq inch blankets the ones john hall sells or are they the lmi ones......??

i will have to look into a dimmer or speed control.....because temp control isn't available on the 220v international blankets from what i could gather...

and if its cheaper and easier to get a lower wattage dimmer the 2.5 might be the way to go

thanks guys

[QUOTE=L. Presnall] [QUOTE=Serge Poirier] [QUOTE=kiwigeo] Serge that bender must put out some heat....are you building asbestos guitars??? [/QUOTE]

no no, just cast iron! [/QUOTE]

"As-best-os" he can!

(Which is very fine, indeed!) [/QUOTE]

Where's Melony, let's sing her a song! The cast iron song! As best os i can!