Bubble free mixing

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Daniel

Daniel

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Jan 1, 2004
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Reno, NV, USA.
I made a couple of custom fishing rods while back. in the process i found a method they use to mix epoxy. keeping bubbles out of the mix is a must for rod making as this is the stuff that will coat the fancy decorative wraps they work so hard at. this is a link to the type of machine they have come up with http://www.rodbuilding.org/library/EpoxyMixer.pdf

I realize they are mixing much smaller volumes than acrylic casting requires. but the idea could work the same. you could also use a metal rod rather than a ball bearing as the paddle.

Mainly I have thought several times of just sharing this information with the caters here in case anyone gets a brain storm as how to apply it to resin mixing.
 
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Excellent, thank you for postsing this. It should not be too hard to adapt - just seems to me we would need larger bearings depneding on how much resin is mixed.
 
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Does anyone know how fast a rotissery motor typically spins? I might have one around here somewhere. The article calls for 18 rpm.

Looking at the pictures more closely, do you know if the ball bearing completely submerged? Looks like it might not be.
 
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How about one of those rock/coin polishing machines? True it's on a horizontal plane, but would just need elevated to the proper angle. A cup big enough to handle 4-8 oz pours and keep the PR in wuld just need rigged up for on the end.

Something like this that sits up on rails to rotate, instead of a center bearing on the ends. Center the container in the one end and you may even be able to use the cap to keep the PR odor down

http://www.rocktumblers.com/rock-tu...mlerstumblertwobarrelrotaryrocktumbler6lb.cfm

Just a thought.

From Soligen, Looking at the pictures more closely, do you know if the ball bearing completely submerged? Looks like it might not be.

For PR it may not work since the bearings would be so deep and may not mix the top layer of the PR.
 
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From comments I have read you want between 12 to 20 R.P.M. with emphasis on keeping it slow. whatever you use as a paddle you want it completely submerged. that is what prevents the bubbles. you could even use a metal rod that runs up the side of the cup. I have read where several people do it that way and think it helps mix faster and keep the edges of the cup scraped off. Either way you stirring device is completely under the resin.

A rotisserie is a good choice and used often. for the small scale of rod making machines they also use microwave turntable motors. I think the Rotisserie motor would be a perfect for pen blank casting.
 
As for 18 rpms. This calibration method is simple. You can easily count them. You can go to the local good will store, buy an old turntable. The are around $2 or $3 here. Take out the motor and attach it to electrical outlet controlled by a light dimmer (simple and cheap to make). Test in motor and adjust the RPMs to 18 (under load).
 
bubble free finish

In the chemistry world they use magnetic stirers, they put in a bar coated with teflon or some sort of plastic. the device has controls, speed and heat. They are sold both ways. I haven't started casting yet but you would put a non-magnetic container on the top and place your two parts of stabilizition medium and turn on the plate to the desired speed. These are on ebay often but pricey. New from a scientific distributor they are very high priced. Dumb me gave one away about 2 years ago.
 
Amazon has the at $70.00. When I was doing a lot of pouring I was using paper cups/tubs,depending on quantity. Less clean up
 
wayno said:
In the chemistry world they use magnetic stirers, they put in a bar coated with teflon or some sort of plastic. the device has controls, speed and heat. They are sold both ways. I haven't started casting yet but you would put a non-magnetic container on the top and place your two parts of stabilizition medium and turn on the plate to the desired speed. These are on ebay often but pricey. New from a scientific distributor they are very high priced. Dumb me gave one away about 2 years ago.
Click to expand...


You can make a 'Stir Plate' DIY......

I'm getting some things together to make one myself.

Fan from an old PC.....rare earth magnet from a dead hard drive, some switches, a pot, little bit-o-wire & some solder and you should be good to go. You could make the 'Stir Bar' yourself or buy one from e-bay.


Barney
 
I've been around custom fly rod building for a long time, and built one of these with a rotisserie motor about 15 years ago. It is still in use, but about to head for retirement. 12-25 rpm will work fine for this, and one of the motors used by many of my associates is out of an old microwave that uses a turntable. I am currently looking for one of those small motors now.

The other solution is going to a rod building supplier and buy a "store bought" one for around $30.00. If you go to the following site, http://www.acidrod.com/tools_thread_fiinish.html and scroll down the page about half-way, you'll see one of the epoxy machines for $27.90.

Also check out the following to see a nicely made home made model. Not that he uses a small piece of steel rod in place of the ball bearings. I've tried both the ball bearings and the steel rod, and the rod seemed to work much better.

Hope that helps.

Rick(mtgrizzly52)
 
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