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From my first acoustic guitar fifteen years ago, I have used a Fox-style side bender that I bought from LMI. It has often done a fine job. But I have ruined quite a few sides as well. Getting the moisture content precise is difficult -- too little water and you get cracks, but too much water and you get ripples. There's always some percentage of sides that crack in cutaways because different pieces of wood bend differently, and you don't get any meaningful feedback during the bend from a side bender.

Over the past couple of months, for the first time, I tried a bending iron. It's too early to make any final judgments, but this thing makes side bending easy. I can bend at almost any radius I choose. Not a single crack or grain lift anywhere, even though I have done some pretty tight bends with highly figured maple. Using your hands gives you immediate feedback from the wood about whether you are pushing the wood too hard. And you don't have to do some complicated calculus to figure out how much moisture to slather on the sides before wrapping them in paper/foil/etc . -- all you have to do is spritz a little more water on in the spot you are bending when the wood starts to look too dry.

So far, my bending time is a little slower than what it would take to set up the side bender and run sides through that. However, as I keep working with the iron, it's pretty clear that I'll get faster than what I can do on the bender. And when you take into account the near elimination of cracks and ripples, the iron is already faster.

I turned on Bob Benedetto's video the other day, and when he demonstrates side bending (which he does with an iron), he explains that one of these days he needs to build a bender, but he hasn't gotten around to it yet. He's pretty quick with that iron, and I can't imagine how he could set up a bender faster than what he's already doing with the iron.

I'm not telling everyone that irons are better than benders -- use whatever works for you. But unless I run into some problems that I'm not seeing so far with the iron, I may have a Fox bender up for sale soon. I'm already struggling to justify the space it's taking up in my shop. And for those who have had some of the same inconsistencies I have with the bender, you may wish to consider picking up an iron.

One more thought -- what a treat it is to be able to finish bending one side, clamp it in the mold, and immediately start bending the other side. No more leaving the sides sitting in the bender for an hour and having to wait to bend the second side.

Different strokes for different folks. When I first started there were no bending machines. We bent by hand for years. Then I discovered the blankets and forms. What a delight to get away from bending by hand.Whatever works for any given person at any given time.
Tom

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A person who has never made a mistake has never made anything!!!

I have much more trouble with an iron than a bender. I get impatient with the iron, and the much broader heating area with a bender and blanket loosens up the entire board in one shot - no worries about moving to spots that haven't heated up enough.

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Jim Kirby
kirby@udel.edu

I bent my first 50 sets of sides on an iron before I got a bender. I now use a fox style bender with 2 heating blankets and have put about 40 sets of sides through it with only 1 crack (try to bend the side too thick). I have virtually no lost sets of wood on the bending machine but have lost a lot of sides to hand bending. I don't try doing cutaways on the bending machine, but do those by hand. Any wood which I can't hand bend into a round cutaway I do as a florentine cutaway (I now only offer florentine cutaways so that is not an issue).

Hand bending is a skill that every builder should have, and I use it all the time touching up sides that may be a little off coming out of the bending machine. I'm pretty quick hand bending, but I can't come close to matching the speed of my bending machine. It takes me about 5 min to bend a side in the bending machine, and probably 15-20 hand bending (depending on the wood). Also I haven't had any real trouble with moisture content. I spray both sides of the side lightly before sticking it in the bender. Once the blankets heat up to 240 I start my bending. The sides come out near perfect, never broken and in 1/4 the time it takes to bend by hand. I think the two blankets really helps (a tip from John Mayes).

Josh

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Josh House

Canadian Luthier Supply
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I admire people that get consistent precise bends by hand, but I could never duplicate the results I get on the machine. Using the moist wrapping paper and two blankets has pretty much eliminated problems for me too. I also thank John Mayes.
I've been using double sides on my tight cutaways so I can bend thinner and that's helped a lot.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Hand bending is a useful skill but machines make things more consistent. The heat source will be the most important thing. Light bulbs just don't do it as well as a blanket. You are relying on refracted heat and a blanket is contact heat , more controlled. Also what is the amount of time you are spending to bend ?
Most times that is the biggest issue. If you are taking more than 5 minutes you are going to slow.
http://www.youtube.com/results?search_q ... 87l2j1l3l0.
I use a paper like Todd as a separator and moisture container. In the Vids I may not show the paper but may mention it. Too much water on some woods can me worse than not enough. It is all about working the wood cell structure. Also wood bending success is as going to be based on wood selection.
Some woods will bend flat sawn better than others. Be aware of run out and look close for wind break and other structural issues. I have been using super soft 2 on the woods that appear problematic. , High figure , off quarter . It all comes down to process so. keep a log and you can dial in that pretty fast.
No need to let sides in over night , just allow them to cool to room temp. I am done bending in about 4 minute and with the heat and cool down cycle , it takes about 45 min to complete a set. I use a temp range of about 275 to 400 depending on the wood. Maple and Mahognay like a bit more heat and just a little water. Maple if made too wet will bend after it comes out of the machine.
Most rosewoods bend well at 325 . As Todd points out , no need to douse the wood. I will give it a light spray but neve make it drippy but will wet the paper well.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Funny how this same discussion comes up over and over. I enjoy both methods but always feel more pleased with myself when I do a successful bend on the iron.

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We are all in the gutter but some of us are looking at guitars.

I'm noticing more and more folks using two blankets, which seams like it might be a wise choice. My question is whether you need to adjust the profile of your bending form to accommodate the added thickness of the additional blanket. Or, is the affect on the shape of the bent sides insignificant?

I've never used a bending machine with only 1 blanket so I'm not sure if it normally goes on the top or bottom. But if you are going to use a blanket under the side then your side will be out the thickness of the blanket when bent (assuming you haven't compensated for that on your pattern). I made all my own patterns using the molds I have as a guide. I traced the profile and shrunk them by the thickness of the side + 1 blanket and slat. My sides generally come out bang on and only needing the occasional touch up on the iron. My guess is that for shapes with shallow curves (Dread) you may get away with your regular profile, but may run into issues with tighter bends like on an OM.

Josh

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Josh House

Canadian Luthier Supply
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House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Thanks for your response, Josh. That's what I figured, but wanted to make sure I wasn't overthinking it.

I bent with one blanket for quite a while but put it on the bottom and allowed for the thickness so when I added the second on the top there was no problem. Two blankets and the wet brown wrapping paper and you can kiss most of your troubles goodby. Based on something I think I read here I put a thin sheet of blue tempered shim stock over the second blanket to protect it from the cauls and that works fine.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Can you talk more about this, Todd? I've been struggling getting binding to bend around the horns on two of my electric models (shaped as in my avatar). I haven't successfully made it around yet though I can almost make it around the upper horn. The lower one seems impossible but I know it's not. Maybe SuperSoft will help me.

+1 on both of these comments. Do the initial shape in the Fox bender and any tight bends and/or tough ups on the hot pipe.

I have been bending with the machine for about 12 years. There is a difference in heating blankets . 5 watts per inch is what I use , 2 1/2 watts per inch are out there and while they do get hot will not reheat as fast. If you think using 2 blankets will work better , than as long as you control the temps and don't leave the machine unattended use them,
I have started to use super soft on some bending when I feel there may be issues. Wood selection is still the most important variable in the process. It is all about process and control for the best results

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it