ROC and FMP questions - GW464

[ProudMarineMom]

Hi all,

New to the forum and to Candlemaking. Started this as a hobby earlier this year because I couldn't afford my Yankee habit. Now I'm really enjoying this and trying to test and learn the right way to make a soy candle. So, probably investing more than what I was spending on tarts!! Anyway, finally found this forum and it has an overwhelming wealth of information.

From what I have read, I probably initially went about testing backwards but now I'm trying to tie everything together that I have learned. I have a wax (GW464), wicks (ECO's), and some good fragrance oils that I like, and a jumble of jars (I know, problem #1, need consistent containers, working on that). And, found a good pour temp. But, I really need to get some good test data on how the wick is performing. Thanks to Stella, Top and others, I've put together a form to track data, I already had my notebook, have some how-to's and other docs (did I mention I was anal?) And, being a Developer as my day job, I do understand the importance of testing.

So, my question is about ROC. I have the weights of the jars empty, full, weigh after each burn, etc., and calculate my hourly rates. The wick chart for ECO 12 wicks, for example, has a ROC of .28 ounces. Is that number what is optimal for that wick during each burn or do you take an average of all the rates after the burn test is complete? Is there an acceptable over/under percentage? Also, what exactly does the Pool Diameter mean on the chart?

Wick Yield ROC Flame Ht. Pool Dia.

Designation (yds./lb.) (oz./hr.) (in.) (in.)

ECO 12 262 0.28 2.2 2.9

Also, after reading some of the posts, I wonder if I've been working under a misconception. What I had read in other articles and forums, Soy Wax needed to obtain a full melt pool on the first burn because it has 'memory' and would continue to tunnel inward if a fmp did not happen intially. The advice I have seen here is that it's not necessary to have fmp on the first burn, slight hang up is ok, wick for the bottom of the jar and the wax should catch up. Is that the better approach?

Currently, my candles are just for friends and family but have had some people ask if they could buy one. Want to make sure the candles are safe before I do that. Sorry about the long post and thank you so much for any help. Still trying to get the hang of the forum/google search so I apologize if this has already been covered... :smiley2:

[topofmurrayhill]

Hi Proud, welcome to the board.

The numbers in the wick data aren't directly meaningful to candle design. They come from a standard test that's intended for comparison of wicks relative to each other. This doesn't tell you anything about how a wick will perform in any specific candle design, or how it should perform. The wax and many other factors will be different.

You may find that when you have a particular candle design working to your liking, you'll tend to see the ROC in a particular range. That is really the only benchmark you have for what numbers to look for.

The short end of test burning time is typically around 3 hours. When you do the short tests, the candle should burn down acceptably -- no drowning out, excessive hangup or other problems that indicate the wick is too small. However, you don't need to have full melt pools or clean glass from beginning to end. You have to experiment and see what results you get, but wicks that clean up too well all the way down are often prone to smoke at the bottom.

At this point it might be a good idea to limit yourself to a 3 inch diameter container. Wide jars often need two wicks to burn well.

[Stella1952]

GOTTA love that OCD!!! Just funnin' ya, PMM - you are on the ball bigtime.

First, before addressing your points of concern, most wick charts I have read are based on paraffin wax tests, so the ROC, etc. will not be the same as for soy wax. It's nice to have some ballpark idea of the values, but don't fixate on testing data based on a wax type different from the one you are using. Your results will probably vary from what you read.

my question is about ROC. I have the weights of the jars empty, full, weigh after each burn, etc., and calculate my hourly rates. The wick chart for ECO 12 wicks, for example, has a ROC of .28 ounces. Is that number what is optimal for that wick during each burn or do you take an average of all the rates after the burn test is complete?

I suspect that is an average derived from testing non-dyed or fragranced paraffin wax. Because I, too, have distinct tendencies toward anality, I calculate RoC after each test burn period for my own amusement and information overload (does the candle burn more quickly at the beginning, during the middle or at the end?), but I calculate the RoC at the end of the candle using the beginning weight, ending weight & total burn time. I don't average the intermediate RoC figures to arrive at the end result, although it seems like they'd be about the same...

Is there an acceptable over/under percentage?

I'm sure there must be, but I don't know what that value is nor whether knowing it would make a huge difference in the scheme of things.

Also, what exactly does the Pool Diameter mean on the chart?

I believe that's the maximum diameter of the melt pool for that particular wick & size. If you scroll down a little past the "Wick Selection" section on THIS PAGE from the Heinz Verhaegh website, you'll see a photo of their "slab test." The "Pool Diameter" is the size melt pool that wick will achieve over the duration of the test. Since most of us don't do slab tests, but rather test in the containers we are using, and we are using soy wax rather than paraffin, the expected size of the melt pool achieved by a particular size wick may vary from the results you are reading.

What I had read in other articles and forums, Soy Wax needed to obtain a full melt pool on the first burn because it has 'memory' and would continue to tunnel inward if a fmp did not happen intially.

I don't agree with that statement, although I will say that if the wicking is off, tunneling can certainly occur. When a candle tunnels, the wick is consumed more quickly than the wax. The wick & wax consumption have to be balanced to work together so they get to the end of the candle at the same time. The depth of the MP is important, too. Soy wax tends to burn down, then out. The "FMP on the first burn or tunnelling occurs because of some memory issue" is a myth.

The advice I have seen here is that it's not necessary to have fmp on the first burn, slight hang up is ok, wick for the bottom of the jar and the wax should catch up. Is that the better approach?

Yes, IMHO, it is. Depending on the wax, FO, size/shape of container & type/size of wick, a candle might not achieve FMP until the second or third test burn! So long as the hot throw is pleasing and the candle "catches up" toward the end (when the interior temp of the container is usually hottest), it's all good.

a jumble of jars (I know, problem #1, need consistent containers, working on that).

Well, maybe yes and maybe no. Working wiith a "jumble" of containers will teach you a lot about how size & shape affect wicking a candle properly. Some shapes are just a PITA to wick - cubes come to mind... Balancing the wick size, the wax, the FO & the temperature of the container (especially at the end of the candle) can be quite challenging sometimes. When trying different shapes/sizes of containers, you will quickly learn which ones are easiest to wick, which ones to avoid like battery acid in the eyes & which ones are soooo pretty you are willing to spend hours of testing (not to mention wear & tear on your last nerve) JUST to make a pleasing candle in THAT container!

Want to make sure the candles are safe before I do that. Sorry about the long post and thank you so much for any help. Still trying to get the hang of the forum/google search so I apologize if this has already been covered...

No apologies needed - you are doing your homework, asking intelligent questions and trying to learn how to make quality candles! HTH Have fun!!

[ProudMarineMom]

Thank you Top and Stella, great info!! I really appreciate it.

:smiley2: Top - I was wondering if those numbers were actually meaningful or applicable to Soy. And, I should have realized it was a comparison test between the wicks as opposed to how it performs in wax. Newbie mistake.

Since I was trying to get the fmp on the first burn, that is exactly what I was seeing at the bottom, smoke and soot. So, I just need to make sure I'm comfortable with how the wick is performing, I'm getting the scent throw I want, the flame isn't too high or the container too hot. Need to work with it until you get the results you want, kinda like a recipe. I agree with the size of the container, especially since I don't want to double wick.

:smiley2: Stella - No problem with dissing me about the OCD. I once took vacation so I could clean the baseboards in my house. Ridiculous right? Working on it...

Thanks for covering the ROC, I appreciate the additional info. And, that the "fmp memory issue" really doesn't apply. Wonder why that seems to be so commonly stated on the web. Anyway, I can move on with life.

Agree on the jars. When I first started I bought a bunch of those 16 ounce apothecary jars. Hobby Lobby had them on sale for half price, looked like the YC containers. Then spent the next 2-3 months trying to get a wick to work. Wanted to single wick, but did try double wicking without much success either. Drove me absolutely crazy. So, bought different jars with smaller diameters and started to really read what I could find on the net. Getting a better feel for Soy. I think I should probably find a jar with straight sides that I like and test with that until I really understand how the wax and wick work together before using the shaped ones I seem to be drawn to (like wine glass shaped).

Again, thank you to both of you for your advice and patience with such a long post. Keep the hints and tips coming! Judy, USMC, thanks for the email and look forward to seeing you on the forum.

J

[Stella1952]

I once took vacation so I could clean the baseboards in my house. Ridiculous right?

Not if your baseboards look like mine!

When we began this Great Obsession, after pouring into anything around here that would hold wax and not burn, I sat down one day and made a decision on what container I was gonna work with first. I chose the 8 oz. widemouth canning jar because they were readily available locally, were not terribly wide (about 3"), had only a slight taper toward the bottom and would not hold so much wax that I would grow cobwebs testing all the way to the bottom. It was a good decision for us because it allowed us to get up to speed more quickly. There's nothing like having a little success at first to boost your confidence... Most of the containers we pour nowadays are still no more than 10 oz. We sell more quantity of the smaller containers than we do the larger of our stock. I see Big'Uns when I visit folks sometimes, but not too many. By the time some folks burn them halfway down, they look as wreched as a kitten left out in the rain all night!

If you are going for a "country" look, the canning jars are great. If you want something classier, but simple, both in looks and to wick, Libbey makes some nice, straight sided tumblers, etc. Was oogling them at Lone Star yesterday morning... They've done a very nice job with that area of their site, BTW. There are measurements & capacities for each container, lid suggestions, a FAQ that tells you HOW they measure their jars, suggestions for how to get the most bang for your shipping dollars, AND good prices!! Cudos to them!! Am TRYING not to look too much - next thing, I'll be whipping out the ol' credit card if I don't stay away from there!!:undecided

Wonder why that seems to be so commonly stated on the web

Probably the same principle as " a lie repeated often enough becomes the truth." It really pays to read a LOT and compare notes with others.

I've been testing some fancyschmancy layered palm wax container candles yesterday and most of the night - JEEZE!! Will these things EVER burn all the way down?!!! *faint* Good thing I'm busy doing chores today or I'd be pacing like a caged tiger... They do smell good, yeah!!

OK, back to dusting - what joy. :rolleyes2 Hope you have fun testing yours!

Edited December 30, 2009 by Stella1952

[ProudMarineMom]

Great Obsession, love that! Understand what you mean there...

I have some of the mason jars around the house and probably should make myself focus and test with those. Just get like a kid in a candy store and want to try everything. I'm thinking the smaller sizes would be better. I was trying to get the large apothecaries to work more for me because I do have a love affair with candles. Have them all of ther house. But you're right, would take for-ev-er to test!

I like the look but my decor isn't really country so stayed away from the canning jars. And for some reason, I don't like the threading at the top of the jar. Can't give you a good reason why, just hard-headed probably. Although, I did see those 8oz square mason jars and like those real well.

Love what Lonestar does with their containers on the site. It is so convenient and you know the measurements of the jar before you buy it. To continue my compulsion of wanting probably impossible to wick jars, I love the Interlude, Vibe, Roman and Whisper. Glass Supply Depot has those as well, along with Anchor's small Curve and Martello DOF. Can't seem to like a straight sided jar can I??!

I actually bought some Glass Glow a couple of weeks ago (I know figure out Soy first ) because I saw a pic of a candle and just fell in love with it. I poured a few containers and the CT is absolutely awsome. Now I need to find a wick that is the right size and has the scent throw I'm looking for. The first ones I did I remelted because I thought I didn't have enough wick. I started reading more on this forum and found out about Palm not needing a fmp and does look like it's tunneling. That's when I really started to notice the same advice for Soy. Learn something new every day. I've tried CSN, HTTP, RRD, LX and ECO wicks and haven't been much impressed so far. Waiting on some CD's and trying to find somebody that has CDN sample packs in stock.

Enjoy testing your layered Palm and try to contain your excitement over dusting. Maybe you should try something equally as thrilling, like vacuuming!!

[topofmurrayhill]

The wick test data is actually not applicable to soy or paraffin candles. It's only applicable to the conditions of the test itself.

Paraffin wax comes in an infinite number of variations. A wide variety of melting points is the least of it. The standard wick test specifies a particular hydrocarbon composition for the wax to be used, but obtaining a sample that matches the standard would be difficult and I doubt many companies even put much of an effort into it.

Even small differences in the composition of the paraffin will cause distinct differences in how it burns and melts. Different companies performing wick tests are also liable to have variations in procedure and equipment.

The bottom line is that the data is better than nothing, but difficult to use in any precise way. You get a vague idea of how one wick size compares to another, because they were probably all tested at the same time in the same way. You may not get a very good idea of how one wick type compares to another because they may not even have been tested by the same company.

[ProudMarineMom]

Top, I think I see your point. There are so many variables involved that it's probably impossible to get a good controlled test of every wick. Since the characteristics of wax is fluid, meaning that one slab or batch of wax will always be different from another, even minutely, there is no way to determine accurate measurements. The charts just give the information on how each wick performed during that particular test.

So, the data is based on a specific test with a specific set of circumstances (as your first sentence states) and would probably yield different results when performed again, even if all of the same steps, equipment, etc was used. Because, a basic component of the test, in this case the wax, will never be exactly the same, which causes the wicks to behave differently.

Sorry, not trying to repeat what you said, just trying to get my thought processes where you are. I really need to try to understand (i.e. keep reading) on why a wick behaves a certain way, mushrooming, no bend, too much bend, etc., to have a better shot at troubleshooting these issues. I know most of these are from impurities in the additives, fragrances, or dyes that clog the wick. Just overwhelmed on what to do to fix it. Testing, testing and more testing... And then test again!

Can I ask a silly question? Can you use smaller containers, say like 6 oz, to test a wax, wick, dye, fo, additive combination until all the components are working together. Then take that data, obviously adjusting the percentages, and apply it to the larger container as a baseline to start testing? Or, is the nature of the beast that it might work fine in the smaller jar but may not play nice together in a larger jar. So, anything learned from the smaller container doesn't really help too much with the larger container.

Not trying for shortcuts. Just want to maybe work the kinks out with a smaller amount of wax before tackling a larger container. Minimize the amount of wax I use creating candles that only a mother could love. And, sometimes even then I want to disown them! I don't live near any candle suppliers and the shipping costs do get expensive.

[topofmurrayhill]

Yes you understand perfectly. Even if the wax doesn't vary significantly from slab to slab, it varies from lot to lot and one tester may not even use the same kind of wax as another. You get what information you can out of it, but there's only so much you can glean.

Even if you're using paraffin, and even if you just happen to be using the same wax that they used for testing (which would be something like what you'd use for a pillar), you'd probably be adding fragrance and maybe additive that would change everything.

The one item in the wick data that isn't about burning is the yield. It refers to the length of wick you get for a certain weight. Sometimes that can provide a WAG for which flat-braided wick types are similar in size if you want to try an alternative type. Due to differences in materials and construction and chemical treatment between wicks, it's no guarantee but it's a starting point if you otherwise have no idea. And it doesn't work at all for cored wicks.

You might be able to learn something about how a wick performs in your mixture by making a smaller container, but I don't know if you learn enough to make it worthwhile. Just for instance, in a smaller container the wax level will drop and expose new wick more quickly. Any observations of trimming, clogging or mushrooming in that container wouldn't be valid for a larger jar.