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I took my first sides out of the bender yesterday and today and I think I see why you should use distilled water to wet them. They bent really well, had them thinned to .08, but there is some greenish staining on the outside and a lot of green spots on the insides. I don't think it will matter overall but do ya'll think using tap water caused it? I soaked them for 10 minutes in room temp water and used two new stainless pieces for the sandwich. After bending, I left them in the bender with the lights on for about 30 minutes then let them cool overnight before removing them.    


Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Ron, there's a lot of mis-information going around about soaking sides. It simply doesn't need to be done. Have a spritz bottle, give it a light spritz to prevent it from charing and bend away. You really don't want to introduce that much moisture into the whole equation.
As for your spots: what kind of wood is it. Some woods will discolor due to heat. It's basically the resins oozing out from within the wood. Try a light sanding to see if they sand out easily.

it is better to use distilled to spritz the wood. minerals in the water can reat with minerals, acids, etc in the wood and cause discolouration.

Black Acaica and Koa will exhibit green streaks and spots after bending but will sand off.

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tim...
http://www.mcknightguitars.com

I can`t vouch for the spots you`re taliking about, but a couple years ago I did some bending on a different type of project using just tap water, and the lime, calcium, and sulfur in our "lovely" smelling water left me with wood that looked like it was impregnated with chalk. I would stick with distilled water.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Here is a question, I have dehumidifiers running in my workshop, and they generate alot of water. Would this water be suitable for use when bending, I have always wondered. ?

The wood is cherry. I think next time I will use distilled water and just use the spray bottle.

Thanks

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Thanks, Tim
This is cherry and looks about like what you've described.
I haven't tried sanding yet. I trimmed the ends in the form and glued on the tail and head blocks. I'm going to go ahead and install the kerfing and inside side braces (I forgot the term for those vertical pieces) and sand the top and bottom contours before I sand the outside of the sides to remove the stain. I guess I'll wait until I've installed the top and back, actually, so it will be more rigid, before I sand.    I'm so excited about the bend going really well and it fitting into the form right now.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

[QUOTE=RussellR] Here is a question, I have dehumidifiers running in my workshop, and they generate alot of water. Would this water be suitable for use when bending, I have always wondered. ?[/QUOTE]

Absolutely it is distilled water with a little sawdust in it from your shop.

Thanks Keith

Russell that's a great idea.

Ron: I find it is a lot easier sanding the side(s) interiors BEFORE gluing in the blocks, linings and side braces. You can sand them pretty easily with a 5" RO sander with 220. This will remove all of the fuzz left from the grain raising during the bending process.

Another tip: Sand the sides (inner and outer) while they are still in the FLAT down to 220 BEFORE bending. Remove all of the subsequent sanding scratches from the thicknessing operation. It's MUCH easier sanding in the flat and then all it takes is a quick cleanup after bending.

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tim...
http://www.mcknightguitars.com

I wrap my sides in a thin paper towell, then aluminum foil and then spritz the paper towell on the side that is getting the heat....this leaves few if any stains and works for most woods.

[QUOTE=Tim McKnight] Black Acaica and Koa will exhibit green streaks and spots after bending but will sand off.[/QUOTE]

Some times more than others    

Thanks, Tim

I did sand the sides to 220 before bending, I was just thinking about the sanding needed to try and remove the stains.      You're right, of course, about sanding the inside to remove the fuzz before gluing anything else to the sides. I don't know if I have the nerve to use the RO sander on the thin sides at this point, I'll probably do that by hand.   
   My wife picked up a gallon of distilled water this morning and a spritzing bottle, so I'll try that next time.

Ronold man38604.5521527778

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Is your bender covered with stainless or flashing. I bent some cherry not long ago on flashing and it looked horrible, covered with green and black stains.It was a chore but the stains did sand off. The second side I used strainless and there were no stains . I think my stain was the zink in the galvanize coating reacting with oils in the wood. Cherry is very oily wood! One caution! Better sand the inside before you line and brace the sides or it`s going to be an impossible task!

Thanks, Dale
No, I'm using stainless. It's good to know that yours sanded out. Did you soak your cherry or just spritz it?

And, did you use distilled water?


Ronold man38604.5977199074

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Just another suggestion for sanding the inside rim. You can pick up a oscillating spindle sander these days for $70-100. They make quick work of sanding the inner and outer rims.Don A38605.7665740741

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Don Atwood
Arlington, VA

You can sand rims with a R/O sander easily and quickly. Just be creative and make sure the wood is backed up and supported on your bench (or in the mold) while sanding it.

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tim...
http://www.mcknightguitars.com

Tim, I assume your RO sander has a flexible pad, I only have the rigid pad with mine, so I couldn't very well sand the bent sides. I guess I need to go ahead and buy the flexible one.

Thanks,
Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Ron: No, mine has the rigid Hook & Loop pad but the outside perimeter edge will flex (maybe 1/2"). Remember all you need to do is knock the raised grain fuzz off and the wood has been previously sanded good and flat, right? When sanding 90% of the rim's inner & outer surfaces you can use most of your pad but when it comes to the outer waist area and inner upper / lower bout curves then you will need to use more of the edge of your sander. Don't be shy, it works quite well. Use carpeting, carpet padding, router grip mats, etc... on your bench surface to back up your work while sanding.

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tim...
http://www.mcknightguitars.com

Before you think your dehumidifier is producing distilled water, which technically it is, consider that the water is condensing on coils that are usually aluminum or copper, both of which oxidize easily. Aluminum and copper oxides will be collected in the water, so the product will have that contaminent plus whatever contamination (often microbial as well as dirt) exists in the collection bucket.

Distilled water is VERY cheap, usually ~$2-3/gallon at the supermarket.

Gotcha, Tim
Thanks,

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

[QUOTE=Jerry Hossom] Before you think your dehumidifier is producing distilled water, which technically it is, consider that the water is condensing on coils that are usually aluminum or copper, both of which oxidize easily. Aluminum and copper oxides will be collected in the water, so the product will have that contaminent plus whatever contamination (often microbial as well as dirt) exists in the collection bucket. [/QUOTE]

Is that why it tastes so funny?

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CVT Inc.
A tour of our shop (Somewhat outdated)
My Personal eBay profile. BCWoodBug

Hi Jerry

That is an interesting point. I used to work for a chemical company and we produced distilled water, as far as I remember both the condensing dome and heating coils were copper ?

I only have experience of one plant so I don't know if this was the norm, but wouldn't that mean that the same elements would exist in commercially available distilled water ?