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I was bending some walnut last night for a European walnut and Italian OM when I got to thinking that I was clamping cauls directly against my blanket. OK I've been doing this for years but I got to thinking, (dangerous thing to do), does any one put an extra slat or even foil/kraft paper on top of their blanket to protect it?





ColinColin S38909.3350462963

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Colin,

I use an extra slat on top of the blanket:

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I should have made it clearer, currently my stack goes from the top; blanket,slat,wood,slat. I was wondering whether to add a third slat on top to protect the blanket. I assumed that it would be understood that I use a slat on both sides of the wood already.

ColinColin S38909.3674074074

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I use (from the top down) blanket/slat/craft paper/wood/craft paper/slat/blanket. So I have two blankets that are unprotected. Works great though, I have to give credit to Cracka-J from Norman for the double blanket stuff.

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Dave Rector
Rector Guitars

[QUOTE=Colin S] I should have made it clearer, currently my stack goes from the top; blanket,slat,wood,slat. I was wondering whether to add a third slat on top to protect the blanket. I assumed that it would be understood that I use a slat on both sides of the wood already.

Colin[/QUOTE]

Colin,

I do from top down: slat/blanket/slat/wood (wrapped in brown paper or baking parchment)/slat. The picture isn't totally clear

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Thanks Dave that was exactly what I was thinking of doing. I too wrap the wood in damp brown paper, I was just wondering whether to add the third slat on top of the whole bundle. I'll give it a go on my next one.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Colin and Dave, with all due respect to both of you more experienced people, isn't it dangerous for your blankets to get the pressure from the cauls while tightening them and also the fact that one side of the blanket is completely exposed and you not only get burnt but get your blankets overheated?

i do exactly like Dave and Hesh and it works great and i also feel that my blanket is protected from both sides with the 2 spring steel slats and the kraft paper and for more heat, i have the 3 bulbs.

John Hall's expertise would also be welcome, me curious of what he'd have to say on this!Serge Poirier38909.3950578704

Hi Colin

I do it exactly the way you are currently doing it with the cauls straight on top of the blanket, I've wondered the same thing Colin, not had a problem up to now.

Hesh

With the lay up you describe you defeating the object of the top slat which is to back the wood whilst it bends ? To my mind on some of the more tricky woods would potentially crack as the blanket can compress easily thus not providings support to the outside.

The more i read this, the more i think that the blanket does not need any protection, i might reconsider what i've been doing up untill now also.

[QUOTE=Hesh1956] The down side of a third slat has to be the extra time required to heat the wood now that the blanket is not directly in contact with the wood/craft paper/parchment/foil/etc.

[/QUOTE]

Hesh,

I don't think time is that much of an enemy. You can see anyway if you have a thermometer monitoring the wood temperature. My guess (having accidentally touched the slats on occasion ) is that the heat transfer will be pretty quick and efficient.

The other thing I don't like about the blanket in contact with the wood (even with the wood wrapped in paper) is that you can get the heating element pattern marks left on the wood.

Each to their own method if it works well for you.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

See I told you that thinking was dangerous.

I'm happy with the way I bend now and definitely agree with Russell that the wood should have a slat supporting it directly on both sides. It was only my worry about damaging the blanket with the caul, though I've bent more than 50 sides so far without any trouble. I'll add another slat on top when I bend my next set (Mad Rose) and see if I'm a happier bunny. In other words I'll copy Dave W!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I don't think John H uses a slat outside the blanket.
I was just reading his directons and he states
Blanket/slat/zoot/slat

Andy

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Andy Z.
http://www.lazydogguitars.com

I briefly discussed the subject of blankets with David Alex, an archtop builder, when he came to visit me last year. He works at a lutherie school back in Chicago or somewhere? where blankets get a lot of use.

David told me the blankets do wear out, mostly due to clamping pressure. He even mentioned a figure, as in the number of sides they typically got out of a blanket before it had to be replaced, but I don't recall it anymore.

Sounds like I'm the only one here who puts the blanket down on the mold and stacks everything else on top of it. This works fine, as long as the blanket is pulled tight at the ends to take the slack out of the waist area.

For easy-to-bend stuff, like well-quartered EIR, all I stack on the mold is (in this order) the blanket, the side, and the caul. Works great. For more difficult woods, like mahogany or padauk, I use slats and wrap the wood in foil and paper towels.

Best,

Michael

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Live to Play, Play to Live

In the USA home centers have aluminum flashing that is 6" wide that come in rolls. My slats and heating blanket measure 6" wide too. I use the flashing between my wood (covered in kraft or parchment paper) and the heating blanket, followed by the stainless steel slat. Works for me!

I bend just like John Hall with no top slat over the blanket.It Works very well.

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Anderson Guitars
Clearwater,Fl. 33755

    Okay here is my 2 cents
    I bend as much if not more than most of you guys. I have the same blanket for 5 years and never used a top slat. It still works. Last year I bent about 200 sets broke 2 repaired the one and lost one.
    The blankets that I sell are industrial grade. I can't speak for Watlow or Omega but I know they are a quality part also.
    I have had 1 blanket fail in 5 years and that was from a faulty connector from the plug to the heating element in the blanket. It was inder warranty.
   They do take alot af abuse but still be nice if you can
yours
john hall

Thanks for your input John!

[QUOTE=tippie53]     Okay here is my 2 cents
    I bend as much if not more than most of you guys. I have the same blanket for 5 years and never used a top slat. It still works. Last year I bent about 200 sets broke 2 repaired the one and lost one.
    The blankets that I sell are industrial grade. I can't speak for Watlow or Omega but I know they are a quality part also.
    I have had 1 blanket fail in 5 years and that was from a faulty connector from the plug to the heating element in the blanket. It was inder warranty.
   They do take alot af abuse but still be nice if you can
yours
john hall[/QUOTE]

Thanks John I use one of your blankets, so I will just carry on as usual. I did have a previous one from LMI, but that one stopped working when one of my chisels fell on it! Your annual bend is 8 times my total so far so I think your blanket will out last me.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

They are tough but I wouldn't use them for chisle pads or hammer testers either
john

Colin, I go slat, blanket, slat, wood, slat, blanket, slat.
Works great for me.

I just use one metal slat under the blanket, nothing on top. Works fine and I don't need different slat for different shapes.