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Side bending sandwich ?
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Author:  segovia [ Tue Jul 06, 2010 4:11 pm ]
Post subject:  Side bending sandwich ?

Hi

I have seen conflicting configurations of heating blankets and slats for bending sides. Such as

slat - wood - blanket - slat

slat - wood - slat - blanket

slat - wood -slat - blanket - slat

Which is correct, number three is out as I only have two slats

J

Author:  meddlingfool [ Tue Jul 06, 2010 4:24 pm ]
Post subject:  Re: Side bending sandwich ?

I use number two, from the inside out.

Author:  Jimmy Caldwell [ Tue Jul 06, 2010 5:03 pm ]
Post subject:  Re: Side bending sandwich ?

#2 for me.

Author:  Zach Ehley [ Tue Jul 06, 2010 6:05 pm ]
Post subject:  Re: Side bending sandwich ?

blanket/slat/wood in paper/slat/blanket

Author:  P@uL [ Tue Jul 06, 2010 8:13 pm ]
Post subject:  Re: Side bending sandwich ?

Zach Ehley wrote:
blanket/slat/wood in paper/slat/blanket


another vote for #2.

Author:  JRessler [ Tue Jul 06, 2010 8:57 pm ]
Post subject:  Re: Side bending sandwich ?

I too use 3 slats

Slat / Blanket / Slat / Wood / Slat

Author:  peterm [ Wed Jul 07, 2010 2:11 am ]
Post subject:  Re: Side bending sandwich ?

number 1 for me.

Author:  Foster [ Wed Jul 07, 2010 7:47 am ]
Post subject:  Re: Side bending sandwich ?

#1

Author:  JJ Donohue [ Wed Jul 07, 2010 8:17 am ]
Post subject:  Re: Side bending sandwich ?

#2...but I also use 3 light bulbs to heat the opposite side.

Author:  Fred Tellier [ Wed Jul 07, 2010 8:26 am ]
Post subject:  Re: Side bending sandwich ?

I use #2 but add a strip of 6" aluminum flashing material to protect the blanket from abrasion caused by the ram and the spring loaded bending pieces.

Fred

Author:  bluescreek [ Wed Jul 07, 2010 9:04 am ]
Post subject:  Re: Side bending sandwich ?

I use the steel wood steel blanket. I have yet to rub through a blanket. In most cases , as I bend about 250 sets a year , that is over 500 cycles and I use 2 benders . I have replaced 1 blanket that was about 4 years old and was my first prototype. I actually wore through the cord as that came off at the side of the blanket near the waist cawl. The 2 blankets I now use are about 3 years old and still work very well.
Protherm is a true industrial product. We used their equipment when I worked as a machinist in a plastics extrusion division. The silicone took quite a beating and we have very few failures as compared to other heaters. That is why I use them. They are a bit more but they are a quality item.
I agree there isn't a problem if you want to use the 3rd slat but it isn't needed . Still I know how some builders are , so I do think Alum flasing would be just fine for the top friction slat.
john

Author:  segovia [ Wed Jul 07, 2010 11:37 am ]
Post subject:  Re: Side bending sandwich ?

HI all

Thanks for your input, I'll try slat - wood - slat - blanket.

The blanket instructions do say do not use in an open environment, resting on the top slat is rherfore not cosidered to be an open environment then ?

John

Author:  Christoph [ Wed Jul 07, 2010 3:20 pm ]
Post subject:  Re: Side bending sandwich ?

spring steel/blanket/slat/wood in craft paper/slat/blanket/spring steel
for me.

Author:  Tim L [ Wed Jul 07, 2010 7:45 pm ]
Post subject:  Re: Side bending sandwich ?

I'd really like to pick up another blanket and use the same method as Christoph.

Most common method for me has been slat/wood/slat/blanket/slat
until I lightly scortched a side of Koa on the outside surface and spent way too much time sanding. For the 2nd side I
switched over to slat/blanket/slat/wood/slat to compensate for that problem and it worked fine.

Tim

Author:  bluescreek [ Wed Jul 07, 2010 7:50 pm ]
Post subject:  Re: Side bending sandwich ?

putting the blanket under the slat is a good way to scortch . I place them on the top. The key is to use the blanket to heat the slat . Check out the bending video on youtube http://www.youtube.com/results?search_q ... ues+creek+
The one thing you will see that there are many ways to do this. Wood is an idiot and doesn't care how many blankets you use. In most cases , the people that need 2 blankets are using a 2 1/2 watt per inch blanket that cannot handle the thermal load. A 5 watt per inch is what you should use. It has enough power to handle the load.
If you feel you need 2 blankets than use 2 but after 10 years of bending , I can do it fine with one. I bend 250 sets a year. A good process will give you repeatable results.

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