The following articles gives a person some pretty good insight about epoxy in general, and also points out some of the specifics of epoxy use, handling, types, etc.
If any part of the article applies to you as a rod builder during your work, consider using the advice.

[bristol29.com]

Roger

Thanks Roger - a really good read. VERY informative.

I find it interesting they give the option of measuring by volume or by weight and supply the data for both.

Be nice if rod finishes supplied that information. It would eliminate a lot of waste.

Then again, it would be nice if rod finishes had easy to access MSDS sheets and technical data sheets to ensure correct use. Only a very few offer either or both.

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Alex,
Actually, if one has an accurate scale it is pretty easy to figure out the mix ratio by weight if one needed to.

One could simply take two idential measuring cups, say 1/2 cup or there abouts. Use the scale to measure the empty cup.
Then, fill both cups with each part of the mix to a predetermined level. Weigh the total amount of each cups weight. Subtract the weight of the cup. The difference will give you the absolute weight of a given amount of part A and the absolute weight of hte same volume of bart B.

The weight difference, is the % correction that you need to make when mixing by weight.

I would expect that if you called the manufacturer of your product directly, they could easily furnish the data to you if they chose to.

Obviously, the larger amount of material used in your % calibration, the better will be the accuracy of your measurements.

Having said that, for most folks the amount of finish ever used at one time is so small that it is likely more difficult to get exact mix ratios, compared to using a simple volume measurement, i.e. measuring by syringes.

Roger

Roger -

Agreed. But why can't you just get it from the chemist/company who developed it? Then you know it's spot on...

Why would System Three supply it (like in your document) and list it in their technical data sheets for other products, but others would not? Consider this - System Three makes one of the more popular rod finishes... so you know that data is known.

Granted scales can be expensive, but for a company to determine that for it's customers isn't really their business. So why not be user friendly and supply both pieces of information?

Again that also brings me back to technical data sheets and MSDS lists. I would hope MSDS sheets are made available to the production rod companies using various products so they don't violate OSHA regs. It's real easy to post them on a home web page.

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Edited 1 time(s). Last edit at 09/12/2010 09:46PM by Alex Dziengielewski.

The manufacturers try to instruct users in such a way that they'll get the best possible results with the product. Measuring by volume is the way to do that as far as most of them are concerned as it requires nothing more than graduated cups or a pair of inexpensive plastic syringes. Many have run into trouble when their users tried to weigh the parts so most have quit recommending that.

And of course you can always call the companies in question and ask them yourself.

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