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Tips & Tricks

Most of us in the BANG! club are beginners, still learning to bend neon.  This page is a collection of things we have learned that make bending neon easier.  There is the concept of "I plus 1", meaning it's easiest to learn from someone who is only one step ahead of you.  Sometimes masters forget what's difficult when you're first learning, because it's been too long.  Whereas, someone on the path just ahead of you can turn and say, "look out for that tree root sticking up there!"

That is the idea of this web page.  If you have a tip for learning something that was difficult, contact Kiki and she'll add it here!
Mark the inside of your bends:

I find I easily get lost once the tube is heated -- I'm concentrating so hard on heating the tube that I forget which way I'm supposed to make the bend!
So I've started making my marks on the side of the tube that will become the saddle of the bend. This way, when I heat, I need only look at the glass to know which way I'll be bending -- I don't have to look at the pattern and reorient it in my mind to figure out again what I'm doing.
Drop and raises are another matter, but you can make up your own indications of which way the drop or raise goes -- *before* you heat!
Contamination of tubes:

Been chatting with California Sign Supply and they made an interesting off-hand comment about uncoated tubes.  He referred me to an article that I found on the web:

It's a bit long-winded, but the gist of it is: sign companies often have this weird problem where a perfectly processed clear red tube will start to turn pink in the middle, and become hot to the touch.  There is no discernable reason for it.  [Or, you're welcome to read the long-winded tome that says basically the same thing "we don't really understand what's happening." :) ]

The solution is a bit extreme: test your box of glass when you buy it, and if it happens, return the glass and change manufacturers.  The more simple solutions are: repump the tube, and/or let it burn in for longer -- often the problem will go away in a few days.

Anyway, this is something we should keep our eyes peeled for, esp. since we think we've been having troubles with contamination in our manifold.  [Note: this problem is *not* related to snaking, so we probably have other problems than this. :) ]

I started scanning so I didn't read all the details, but the guy at CSS seemed to think that coated tubes have less of this problem.  [The article begs to differ.]



PS Actually, there is a good bit of interesting technical info on what is probably going on.  But save yourself the time and scroll down to where it says "Read on:"

>Weathering is the product of sulfur dioxide and carbon dioxide combining
>with the soda in the glass and water in the air to form crystals of sodium
>sulfate and sodium carbonate. This process begins as soon as the glass is
>cooled down after the initial manufacture.
Blue phosphorus makes glass weak:

Mr. Foo and I have been having an interesting conversation about coated glass, in particular the blue phosphor coated clear glass.

Foo said this:

>The rate at which the coating fuses to the glass varies with the
>temperature.  Hotter is faster, cooler slower.  That means that
>working fast is good, slow is bad.  A large cool flame is good,
>a small hot flame is bad.

And I replied this:

>But if the fusing temp is only a *little* bit beyond the melting temp, then
>working cooler *is* better, because you're more likely to heat only just
>enough to bend and no excess heat.
>BTW, this might make a *lot* of sense with the blue unleaded glass vs. the
>leaded glass for the fuck sign -- the unleaded glass requires more heat, and
>so the coating might more easily fuse and make the glass brittle.
>The leaded blue still has some troubles -- the U bends keep breaking on the
>u in fuck.  But now that makes sense, since I have to heat the U bends much
>more.  They crack on the table...
>I will try bending with cooler heat and see if that helps or hurts.

Coated glass tends to have troubles like this anyway, but it looks like I got stuck with a particularly hard color to work with. :(  Esp. in unleaded glass. :(

I'm sure the coating is fusing to the glass -- and noted this before -- because I could not wipe off the coating in areas that had been heated.  That was kinda suspicious.

Lumpy welds: When welding, there tends to be a thick spot right at the weld where you push the glass together.  You might also get thick spots at other times too.  Heat the glass until glowing red and molten, then take it *out* of the heat and *do nothing* for a moment, then stretch or blow [depending on the diameter.]  This allows the thinner parts to cool, while the thick parts retain their heat.  This works so amazingly well!  I have recovered some really lumpy welds with this trick!  It's really amazing feeling the thick parts doing the stretching, while the thin parts remain rigid.  [Note: this is why blowing hard makes a thin soap-bubble -- the thin part suddenly cools and becomes rigid, while the still-hot thick part is fluid.]

To recover thin parts in a lumpy weld is far more tricky, but I'm getting better at it.  Since thin parts heat faster, *gather* them.  Heat and let them "fall" together, while being careful not to *fold* the glass.  This actually works, but it is *very* delicate process.

By using these two methods together, I have recovered from some really knarly lumpy welds!  If you have a weld that's so bad you're ready to give up on it, then give this a try just to work on your skills. -- you've got nothing to lose at that point anyway, and skills to gain, even if you fail miserably. :)

Reworking bends, I'm finding, is still too difficult.  You really must do a good job the first time.

Tips from the Neon Workbook:

Side-welding or tubulating coated glass: I'd wondered how to do this, but the book says, "No need to wipe away the coating because it is baked into the glass at this point."  I've not tried it, but you can bet I will be!

"Try over-bending an L-bend.  When adjusting back, the backside gains thickness."

"Form a sharp curve between two shallow curves -- heat the sharp curve first, then all.  Don't heat the first curve to *melting* though."  This is good for something like, say, um, bending a lower-case script "f". :)  I've been using this trick to make curves that are purposely uneven -- heat one part some first before heating the rest and it will bend more.  Very handy trick!

"If using a form, bend then remove -- the glass shrinks!"  Something to keep in mind for anyone going that route.

"Neon is most efficient at 1mm [of pressure] but causes sputtering.  Single-ended tubes like 1/3 - 1/2 recommended pressure."  [Meaning if you should fill at 12mm for the given diameter and gas, then fill at 6mm for single ended stuff.]

Now this lower pressure stuff is *very* interesting.  i need to go re-read that part again.  It seems like I read that single ended neon has far less worries of sputtering.  [I wish I had written down the page number... :( ]  This is significant for plasma work, and it might be worth experimenting with.  if this is the case, there's no reason we can't use pretty much anything we like as an electrode.

Another note, specifically for Doug.  Note that the cheapy plasma globes have no metal in the chamber.  The electrode is a glass nub stuffed with a metal dishwashing scrubby.  I kid you not!

I have been thinking a lot about reversing the electrode *into* the vessel -- this is why all that weird inside-side-welding I was playing with.  if this could be done, there are two advantages: first, the electrode does not stick out and it's easier to mount.  Second, we can fill with *any* gas we like, since there's nothing to corrode.

Doug, let's compare notes on this.  I want to design some "drop-in" electrodes for bottles.  Note also, that with this same idea, you could "drop-in" a piece of glass and solder it in solely for the purpose for sealing the top of the bottle, then drill the electrode hole in the bottom.

The main issue is how do you tubulate it?  The simple answer is to tubulate separately, but I want to find a way to tubulate in the electrode itself by welding to the side wall from the inside.  I'm still trying to see if this is possible, but in the meantime, we have something to work with!

"Electrodes exceed the melting point of lead glass during bombarding."  *Very* important information.  And confirms the notion that welding a broken electrode will not damage the shell due to heat.  [The burning of the propane and all the chemical reactions going on around it, is another matter. :)  But I'm curious to try it and see how "bad" it is.]

Bending to a pattern: I find when I'm bending to a pattern, I often get lost in the heat, then forget what I'm doing, which way to bend!!  Now that I can generally make the shapes, I'm workig on perfecting my bends along these lines -- relax in the heat, and now concentrate on the bend itself.

One way to help think about how to do the bend is to practice bending with your blow hose.  Don't laugh!  Better would be to practice with wire, but you [generally] always have your blow hose.  Practice which hand goes where and which way is "down" in the bend.  Practicing bends for doing lettering is far more crucial than abstract patterns.  There's no room to mess up and go the wrong way.  Also, the shape you're often holding is convoluted and backwards, and you have to do the bend with it facing down, and so it's easy to get lost where you are.

Loops: For loops, the trick is to heat, then fold up to a double-back, *then* twist for the loop.  Do these as two distinct bends.  Also, it needs a good bit of heat, and will probably need to be blown out.

[Background to these tips: I [Kiki] was in a neon class, and my midterm was to utilize an 18"x18"x18" box, so I wrote "FRAGILE" on the side in tubulation.  The tubulation was easier to bend [though it had its own issues] so I could focus on just the technicalities of lettering.  It was a *great* lesson!  So with that, here's some things I learned.]

**Drop-bend: I've paid special attention to this bend, because, as Foo suggested, it's possibly the most important bend in neon.  Certainly true for lettering!  [Same goes for welding, but welding is easy to get the hang of -- just heat it lots.]

I asked what the trick was of students who were doing well, and asked the teacher too, and Bill had the most interesting comment: "heat as much as for a 90-degree bend.  Basically, it's a 90-degree bend."  After he said that, I kept looking at it -- it should need more hot glass than just a 90-degree bend...  But I think he's right.  I've been heating a *little* more because I can't help myself, but he's right: basically, it's a 90-degree bend.  Hmm!

Also, you *better* do the bend before doing the drop!!!!  This is *very* important!  [And I keep messing this up!]  If you drop first, then bend, the drop will twist, stressing the glass.  If you bend first, then drop, the bend stretches the glass, then the drop stretches the glass -- no twisting.  Folks, it is night and day!  Bend, then drop.  Wax on wax off.  Do it over and over until you don't think about it.

**Lettering: The trouble with the "R" was in doing the curved leg.  [I was *determined* that the R would have a curved leg, not a straight one.]  When do I do the leg-curve?  Well, you'd *think* you'd bend the big curve first, then double-back, then do the drop to start the leg, then do the leg bend.  Well, first of all, don't *dare* try to do the leg-curve if that drop is hot!!  It'll soften and you'll ruin it.  That was try #1-3 or so.  So I tried doing the bend first, but I did it the wrong direction.  Try #4.  I went back to trying to bend in place after the drop -- *after* cooling -- but it still heated up the glass and the drop tended to bend and stick to the top curve!!  ARG!!  That was try #5 through about #8 or so.  [I was getting snippy by then.  It was about 11:15pm, and I wanted to finish and pump it out, and the BART closes at midnight...  But Foo saved the day by saying he'd take me across the Bay to the Coliseum BART.  Yay, Foo!]  I tried doing the leg-bend separately and welding, but that double-back was just too dang close, and I kept messing it up.  I think I eventually did a double-back to see where the leg-bend would be, then re-heated and unbent it some to get it away from the other glass, then I did the leg-bend, then an attempt at the drop, then fixed the double-back, then fixed the drop.  It was hell, pure hell. :)

That probably makes no sense in text, but, trust me, it was hell. :)

Part of the problem was that even though I was bending in the 5-point cross fire, the heat spilled to glass that was nearby.  That tubulation is *tiny*!  It's pretty tight getting in there.

**Lettering book: Also, the lettering book was *invaluable* in telling me which bends to do first!  BANG! should get this set.  [Bill, would you send me the website info on ordering them?]

**Cheat by welding: Another important lesson I learned is bending two halves of a letter and welding them together.  I used this All. The. Time.  It was hard for my purist heart, but necessary in the end.  So necessary, I got used to thinking about difficult letters in two parts, and I rapidly got over it in my fits of frustration. :)

The "G" was so hard, I gave up and bent each curve separately, then welded them.  Note that the weld was tricky too, since that line that turns into the G [ie the line that's the difference between C and G] is very close if you try to weld in the middle -- so I had to off-set the weld!

**Enough heat:
Foo said he noted that it's best to heat until the glass starts to collapse, then bend.  I think, too, you might gather the glass just a tad [meaning push it together a tad, and let the surface tension pull it together and make it thicker] -- this is harder with phosphor glass, because that can cause the phosphor powder to come off inside...

At the same time, I think one of my problems is *too* much heat.  I seem to take the glass to the point I lose control of it.  I've been backing off on the heat just a tad so the glass is more plastic.  I need to find a balance, because the more you put a bend back into the fire, the more certain you'll ruin it.  Which brings me to my next point:

**Don't re-work bends:  Screwed it up?  Too bad for you.  Because if you try to re-work it, it'll just get worse.  You can when you're a master, but not now.  You're a beginner and you suck.  Throw it away and start over.  I am getting used to this... :)

I actually learned this folding origami.  I'm a little shy to admit that I've folded a thousand cranes.  I learned a *lot* about folding while doing that.  One of the big ones was: you can't fix a bad fold.  Nope, you can try, but it'll only get worse.  You just have to breathe, and fold confidently the first time.  It's all a Zen thing.  There's just no way around it.  You can't think too hard.  You can't even *look* too hard. :)  Breathe, and do it.

Neon bending feels about the same.  Skill = confidence.  Experience breeds confidence, but you can also seize confidence and skip all that tedious time. :)  I'm working on it. :)


Drop-bend: do the bend, *then* the drop.  If you drop then bend, you'll twist and stress the glass!

Be aware of what's recently heated.  Let things cool before bending again.  Good idea is to work on multiple things at once.  This can actually be the same project if you take the next bit of advice below:

Don't be afraid to bend two different parts, then weld together.  Get over your pride.  Just take a breath and use this cheat.

"Zen and the Art of Neon Bending."  Just bend.