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What pencils/markers to use on rig materials?

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PRH and Poynter Vol. II recommend using Dixon #134 pencil (was Para Gear S7967) for marking canopy material. Unless it's called something else now, I can't find this type of pencil in the usual places. Is there a good alternative that I can buy at the local Jo-Ann or another arts & crafts store that's known to be safe on ZP fabric?

Should something else be used when marking a fabric pull test? TS-108 recommends "approved ink or a black Sharpie," but I'm not sure about the latter being free of potentially harmful chemicals (as far as I know, most Sharpie ink is acidic).

In general, what pencils or markers should be used on various line types and nylon tapes/webbing? I know that some riggers don't like seeing Sharpie on the reserve bridles, but is it considered safe for things like closing loops and different line materials? What do the manufacturers use for marking the reserve bridle?

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I wouldn't choose to use any grease pencil. By the simple nature of it it can migrate.

I have some of the old Dixon pencils that were good. While they have some binder they are more like chalk pencils. Besides those some testing a long time ago determined that Staedtler Lumicolor were the least destructive. It took a trip to austria to find them. I've sense found them in the US but haven't looked in a long time.

I know lots of folks and some manufacturers use regular Sharpie's but I wouldn't chose those either.

I'm pretty sure there was a non Dixon equivalent to the old Dixon pencils. Trying to find the reference.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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A variety of tailors' chalks work well and brush off easily. The key is finding soft chalk that brushes off easily.
For marking suspension lines and closing loops, I have use a variety of alcohol and toluene-based markers (e.g. "Sharpie"). I have also used various felt markers to write on reserve bridles. The incidence of chemically-degraded reserve bridles is below one percent.
I have also seen canopy fabric (both F-111and ZP) marked with a variety of inks ... again zero degradation over time.

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I just used black sharpie in marking my line as I built my new lineset. I'm not worried about degradation of the line. It's basically plastic. I would worry more about nylon but there are better options that don't bleed into the material for marking canopy fabric. I'd stick with my marking pencils for that.
www.facebook.com/FlintHillsRigging

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Experiment, part 1a: Regular Sharpies, an "acid-free" Sharpie, and plano china markers. I'll post more photos next week to see if these china markers make stable lines or grease spots.

Experiment, part 1b: Same set of markers on ZP. Photos to come. The Sharpies did not bleed as much on the ZP. The first ZP try with plano china markers wiped off pretty easily, so I re-did the sample. Wiping off easily is good or bad, depending on how long you need the mark.

Experiment, part 2: Still in process. My plan is to make two identical samples of reserve bridle 2" polyester, one clean and one contaminated with mass quantities of Sharpie ink. Once the ink dries, we'll pull both samples to destruction.

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Nice for someone to do some testing. For experiment 2, part 2, how about some intermediate stages that might more easily find an effect:

Can one do any sort of test for acidity, where acidity is a good indicator of possible damage in the longer term? (Still got fresh enough Bromocresol blue for old Phantoms etc?)

If looking for strength loss, even though polyester isn't the same as nylon, one might be more likely to find a measurable effect if using the sharpie to blacken something with less strength to begin with (e.g., F-111)?

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This work was already done in the early 90's, I believe by Dan Wilcox at the same time he.did the webbing damage testing. I've been trying to find the info but haven't yet. At that time the dixon 134 pencils and a Staedtler lunicolor pen were the best. Everything should some degradation.

The effect will not be instantaneous. Simply waiting until it dries is not.enough. Suggest several samples made and test over at least a year, enough samples for several years would be good. I found several military papers in my stacks on material aging. They did accelerated aging at several temperatures for periods of months. That would be good also except you would need to age unadulterated samples for each time point also to account for purely environmental changes. In the military papers they also used real world samples take from new old stock decades old. I certainly can find a reserve bridle that's had three feet of sharpie writing on it for twenty years. I have to believe Natick has already done this testing. Might contact Natick PIA rwps.and ask.

I used to design stability studies as part of my job.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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It would be nice to see how the old studies were done, but if we can't easily obtain the same products today, then I think it's time to repeat the experiment (thanks mark!). I assume it was never determined which chemical properties of the dixion lead made it safe(er) than the alternatives? That information would have been more useful than just a specific production recommendation.

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Bromo cresol green is a very crude test of pH and doesn't change color until pH 4.5 to 5.5. (Neutral 7 on a scale of 1 to 14) It worked for the mesh but not good for much else. Nylon is actually fairly resistant to mild acid damage and any measurement of a marking device would not be predictive. You could say neutral better than not but other properties of the marker may be important. The "acid mesh" problem was never just acid. On one canopy two panels of white material sewn next to the same single piece of mesh were completely different. One with a strength of about 1lb and one full strength at 40 lbs.

That being said some measurement could be done but I no longer have access to a lab.

Interesting enough the military papers found a spectroscopic indicator (by FTIR) of long term nylon 66 degradation that I didn't see when I tested samples of degraded and non degraded material. I may have missed it or more likely the damage was of a different chemical nature.

I don't recall if bromo cresol green is still being sold by paragear but I do have a stock of dry powder and could make some up if anybody still wants some.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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