While many of you may have noticed this before, I have not seen reference to it here on this forum since joining the site 6 years ago, hence wanting to share my observations in hopes of possibly enhancing your epoxy “lenses” over threadwork, especially the longer ones which are more susceptible to waves and irregularities. Although not a “solve-all” method to achieve that perfectly level, flat lens covering our threadwork, it has improved the appearance of the epoxy covering my 3in long / wide inscriptions by a noticeable amount. I cannot afford any scientifically derived data for the few who insist on such, but for everyone else it may just improve the “looks” of your epoxy.
I purchased, modified and employed the triple CRB 9RPM drying (curing) motors (110VAC) in my dust-free curing cabinet; they work OK. I immediately noticed that the motors have a reversible, directional mind-of-their-own, randomly rotating in either direction when turned-on. I am uncertain if ALL curing motors are the same! At first, I did not pay much attention to it and just considered it the-nature-of-the-beast (Only Roger Wilson can explain exactly what’s going on {if it is even important}). But since I had to deal with the phenomenon anyway, why not use it to my advantage!?!?!?
I decided to experiment with rotating my curing epoxy in both directions, changing every 5 minutes for the first hour, every 15 minutes for the second hour, and then when convenient or I thought of it after that. I am convinced there has been a noticeable improvement in the leveling of the epoxy; maybe not a milestone, slap-in-the-face difference, but an improvement nonetheless!
Again, I do not have any quantifiable data to support my observations; I do not have optical comparators or other sophisticated equipment. But the human eye can depict a difference of less than a thousandths of an inch at the proper angle. Do your epoxy coverings require such? Maybe, maybe not. But with all the hair-splitting involved with rod building, why not apply such to our epoxy “lenses” as well? I hope this might possibly help.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

Mark Talmo Wrote:

> I decided to experiment with rotating my curing
> epoxy in both directions, changing every 5 minutes
> for the first hour, every 15 minutes for the
> second hour, and then when convenient or I thought
> of it after that. I am convinced there has been a
> noticeable improvement in the leveling of the
> epoxy;

I am leaning away from your conclusion because when a rotation of a liquid epoxy is reversed, depending on the viscosity of the curing epoxy, a bulge will develop on the bottom side at the time of spin reversal due to gravity.

If this process is continually repeated throughout the curing process, it could actually cause one side to be thicker than another.

I truly believe spinning in one or the other direction continuously is best for leveling out the epoxy.

I view reversing the rotation as detrimental to this leveling process and the epoxy could begin to harden beyond leveling ability during this reversing situation that could cause the gravity bulge that cannot be undone.

My opinion of course- and unproven and no empirical data or test results to back it up.

My experiences seem to correlate with Mark's. For those who finish by hand or with finishing motors or drum dryers that don't reverse, concentric and level finishes can be improved by periodic 180 degree rotation of the rod until the finish no longer moves.

Then in respect to this, regardless of the direction, a slower rotation should allow the flow or movement of the finish to cover an entire rotation lending to a better leveling of the finish

Ron Weber Wrote:
-------------------------------------------------------
> Then in respect to this, regardless of the
> direction, a slower rotation should allow the flow
> or movement of the finish to cover an entire
> rotation lending to a better leveling of the
> finish

This is a subject that is very difficult to judge and accurately determine what is the correct rotational speed as it would depend on the weight and viscosity and size(Length, width & depth) and temperature of the coating meaning that the rotational speeds should be as varied as the viscosity changes are. I see no way to measure such a thing, but can only watch the epoxy and adjust speed based on what I see happening.

Am I on track here?



Edited 4 time(s). Last edit at 01/17/2022 08:56AM by Kent Griffith.

If you truly want a perfect epoxy, you're going to have to ditch the mechanical rotation units and turn the rod by hand, 180 degrees, as often as needed. This will give you the most perfect finish possible, but requires that you baby sit the rod for 2 hours or more. The key to hand rotation is to only turn the rod as needed and always by 180 degrees. Later in the process you can orient the rod so that the finish can more evenly cover higher areas and edges such as the guide feet.

Unfortunately most builders do not have the time to spend doing this and thus mechanical rotation is the fact for many. 18 rpm is probably the most versatile speed and works with a wide variety of finishes and viscosities.

.............

Mark,
Another method to consider is to get yourself a variable timer. I have one connected through the power supply to my drying motor. The timer has the ability to turn on for your defined period, turn off for your defined period, and stop after a defined period. I have mine set up to rotate for a period of 20 seconds, turn off for a period of 80 seconds, and stop after 4 hours. The stoppages occur at a different point on every rotation, giving the epoxy a chance to flow over the wrap and release bubbles. You could calculate the times to stop on every 180 degrees as Tom suggests if you choose. This method seems to work well for me. When I'm done applying epoxy, I set the timer and walk away. The timer does the rest.

Ed Kramer Wrote:

> The stoppages
> occur at a different point on every rotation,
> giving the epoxy a chance to flow over the wrap
> and release bubbles.

Ed will you share with us how you apply your epoxy that causes bubbles?

I've never really had an issue with this so I am curious.



Edited 1 time(s). Last edit at 01/17/2022 10:41AM by Kent Griffith.

The reason hand rotation is superior (provided you have the time to do it) is that you are only rotating the rod when and where it's needed. And the most important part is that all epoxy finishes are self leveling (check your mixing cup for level) but guide wraps are not level. With hand rotation you are able to keep the rod positioned so that the un-level portions of the wrap, which is typically the thread over the guide feet, is kept so that additional finish is able to cover that area, particularly the thread on the edges of the guide feet. You only rotate as needed and for as long as needed. In effect, you are able to manipulate the finish to go where you want it to go.

But again, if you don't have time to watch the rod, stick with a mechanical device. They work fine.

............

When I first stated building I hand rotated all the rods I built. Unlike Tom, I turned the rod a quarter turn in a clockwise direction every 10 - 15 minutes for the first hour or so then every 30 minutes or so for the next hour or so. The reason I turned clockwise was so I would not forget the direction I was turning. I think turning 180 degrees should also work. I had no problems getting a nice flat and level finish. Another advantage of hard turning is you quickly realized when you use to much finish since you see sagging very quickly. The sags could be easily removed early on without any ill effects. When I moved to using finishing motors to turn the rods, I found the slowest speed motors (4-6 rpms) not only gave the best results, but also lasted longer. If you use to much epoxy and rotate at higher speeds (>18 rpm) you can easily get football formation on your guides, due to centrifugal force. Just my observations and opinions.
Norm

The reason I mentioned turning only as needed rather than at prescribed timed intervals, is that it allows precise control over the epoxy and where it goes on the wraps. By turning only when the epoxy on the bottom starts to get a little thicker than that on top, you never have any sags or uneven areas. And... that last hour you can really dial in the epoxy on the guide feet and guide feet edges.

Beginners that do not own a mechanical rotator should never think they can't start rod building without one. You can get just as good and even better results by hand turning. It's not for everybody but if you have the time, it gives great results. Otherwise a mechanical "dryer" is nice to have.

..............

This is how I did it when I started building rods...and did it like this for a long time.
I would turn the rod 180 degrees:
Every 5 min. for the first 30 min.
Every 10 min for the next 30 min.
Every 15 min for the next hour.

I will admit to having the occasional rod bumps.

My goodness - life is simple.

Apply epoxy, turn on the drying motor for a constant speed that is fixed at a speed between 8 and 18 rpm.

Come back 24 hours later and the rod is dry with a perfectly smooth and level finish.

Next subject.

p.s.
This explanation is dependent on the fact that the epoxy needs to be thin enough so that the epoxy can flow and self level as needed.



Edited 1 time(s). Last edit at 01/17/2022 02:01PM by roger wilson.

Hmmm, so you are basically telling us to sit on it and rotate!

12 RPM for me in whatever direction the drying motor wants to go. For a minute I thought we were going to be taking into account the Earths rotation in the northern hemisphere.

Cabin fever must be setting in with ideas about reversing guide placements and complex drying regimes. Put the proper amount of a well-mixed, quality epoxy on wraps and then let your eyes tell you if the speed you are turning is allowing for leveling. I have an ancient 6RPM motor that worked just fine but started to run hot. I now have an adjustable one that I use within Roger’s range with Kent’s eye-test guiding me. I turn it lower when the epoxy is fairly set, but only because there is a spot where it runs quieter. A hand planed and glued Tonkin blank might deserves more meticulous methodology, but it’s hard to see flaws from the KISS approach that are close to being meaningful on production carbon. Gen4 just rocks if you don’t put way too much on.



Edited 1 time(s). Last edit at 01/17/2022 10:49PM by Kendall Cikanek.

Let me go grab a Arduino microcontroller, stepper motor controller, some stepper motors and write up a control program - then I can have it automatically turn my rods 180 degrees on a timed interval - or if 60 degrees is the magic number we can do that - or random rotation direction & distance.....

:)

Michael Ward Wrote:
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> Let me go grab a Arduino microcontroller, ...

Thats my kind of thinking...
Maybe just an ESP32 and a relay.

Michael Ward Wrote:
-------------------------------------------------------
> Let me go grab a Arduino microcontroller, stepper
> motor controller, some stepper motors and write up
> a control program - then I can have it
> automatically turn my rods 180 degrees on a timed
> interval - or if 60 degrees is the magic number we
> can do that - or random rotation direction &
> distance.....
>
> :)

When you are done, gravity will remain very close to being a constant ????.

And there is no such thing as centrifugal force. Inertia of the mass (epoxy) tries to send that mass in a straight line, at constant speed (Newton's Laws of Motion). Centripetal force (center seeking force), in this case molecular adhesion, holds the epoxy in place, as long as the rotational rate is slow enough to not overcome the adhesive, and viscous properties of the epoxy. I'm sorry, but just couldn't stop my brain from screaming my physics professor's voice at me - THERE IS NO SUCH THING AS CENTRIFUGAL FORCE!

Now that that's out of my head, Ihave had no problems with my thread wrap coatings, usiny my dryer at about 10 rpm, and Gen4 light. it flows nicely, releases bubbles, and self levels. Depending on the build, i will apply from 2 to 3 coats.

Tight Lies and frisky fish

RJF