44 replies to this topic
Posted 02 January 2008 - 06:59 AM
Their has been a spate of posts concerned with supply shortages and various problems with eyes. Over the last year I have read a lot of articles about making eyes. The most promising being white base, black dot with a blob of epoxy for the lens. Without having made one myself, I can imagine a problem attaching them to the lure because of the complex curvature. So I decided to explore the subject for a solution myself and this is what I came up with.
In order to fit to a compound curvature, the eye needs to be manufactured from a soft, flexible material. I decided on silicone, with the pupil made of black card and a hole punch, simple and very quick. But the flexible material is not enough as it is always trying to return to the flat, leading to the edges pealing. The solution is to make the back of the eye concave. This means that although the back face does not necessarily match the mounting face, it is a lot closer, but in addition, the flexible eye, trying to return to its original shape, is flexing into the mounting face rather than pulling away.
A mould would be required for the eye, consisting of a convex lens and a concave back. To achieve this mould shape, I chose glass marbles. Generally available in toy stores in two sizes, which suit our application perfectly. Should a deeper or smaller diameter eye be required, ball bearings are available in just about every size imaginable.
Next, the mould material was considered. RTV would probably not work well, due to the adhesion of the silicone, being a similar material. Also, RTV is expensive. As the mould would be fairly simple, it seemed overkill to use RTV, so I explored Plaster of Paris (plaster of Paris), sealed and coated with epoxy or polyester resin for a smooth finish for the lens.
Next, I did some adhesion tests. This proved to be a big problem. The silicone stuck firm to everything. Clearly the smooth finish of the mould surface was not going to be good enough, even smooth plexiglass material was adhering so hard, it was impractical. I then performed a few tests on wax. This was the best solution. Not perfect, as the mould surface would have a very limited life due to erosion, but with a master pattern, the moulds could be re-melted an re-cast.
Unfortunately, I have been unable so far to obtain the marbles, to complete the test. But have decided to publish these findings, should any of you care to try the method.
Roll a lump of soft clay or plasticine into a sheet about 5mm thick.
With a small marble coated with pam oil or similar, make depressions in the clay. Space them such that a large marble can sit in each dish with clearance from each other.
Form a retaining box and pour Plaster of Paris. This gives a positive mould. When fully cured, repair any faults, bubbles etc. This should be sealed and coated with epoxy or resin for a smooth finish.
This is now the master mould, from which all the working wax moulds will be formed.
several wax castings can be poured in an hour, with the use of a freezer.
Place a blob of clear silicone in each dish. With a piece of plastic (plastic bag material) covering your index finger, dipped in pam oil, spread the silicone to cover the area of the dish shape. Excess is not a problem, in fact, desirable.
With the tiniest touch of silicone on the handle of a brush, pick up a black card pupil and place it onto the silicone, centre or off centre as required. Next, add a blob of white silicone to the pupil.
Place a large size marble, previously dipped in wax onto the silicone. Excess will be squeezed out. This is OK and does not need to be cleaned away.
The silicone eye will dry in a few hours, as the thickness is not too great. But leaving over night is a good idea.
Once dry, the eyes will peel very easily from the mould. Wash in soapy water to remove any wax deposits.
To cut the eyes out, a suitably sized round metal tube is required. Using a file or dremel, sharpen the end to a cutting edge. Using a rubber mat as a backing, the eyes can be quickly and simply trimmed from the waste, giving perfectly formed eyes, ready for use. The eyes may stack inside the tube, but this is not a problem, as they can be pushed out with a pencil or suitable rod.
Rather than using hundreds of marbles for the back, they could be half cast in wax. As I said, not tested to conclusion, but I am confident that the method will work. After a short learning curve, I estimate 300 - 500 per hour is a possibility. I suggest that you lay some wax down and test the silicone materials out for finish etc.
Posted 02 January 2008 - 09:08 AM
How about painting the eyes on the lure, and then putting drop of epoxy on them one at a time, to give the epoxy time to set so it doesn't sag or distort. Then coat the whole lure.
Posted 02 January 2008 - 09:11 AM
Or using your marble method to make convex epoxy eyes, out of the extra epoxy that's left over after you coat some lures. Once the epoxy sets, you can paint the back with the black dot, white overlay, and there you have it.
Posted 02 January 2008 - 09:37 AM
Yes Mark, that would work.
One problem with the silicone is finding a clear that is truly clear. Also, the finish given by the wax is not perfect. But, the final top coat takes care of that.
The concave rear face in epoxy would be better than a flat face, but a gap will still exist when the eye is fitted.
Design is almost always a compromise of some sort. Hopefully, more ideas will come to light. 3D eyes is begging for a better solution. After using all that expertise to create the masterpiece of fish traps, it seems ludicrous to buy the eyes.
Posted 02 January 2008 - 09:52 AM
I posted this before but i will do it again.I took the 3d eyes we all use and stuck them on the underside of a plastic cap.I filled the cap with rtv(it doesnt use much) You end up with a nice mold.Im just looking for the right material to make the eyes.
Posted 02 January 2008 - 10:47 AM
Vman, I was reading your post and when you dismissed using RTV had you considered trying the mold release they sell? It works great for creating a two part RTV mold, so the silicone shouldn't stick ( I am pretty certain all it is is wax dissolved in some sort of solvent).
The nice thing I see about this is that the RTV could be flexed allowing you to "Plaster of Paris" the lenses out. Also could create a mold with enough holes to make a bunch of eyes at once.
For the lens material I see they sell a solution to create clear water for model train scenes. Wonder if that would work? Here it is on Micro-marks' website, they don't have the easiest site to navigate, but they have a wonderful catalog. The PDF of it is online. It is on page 107. http://www.micromark...pdf/100-109.pdf
Posted 02 January 2008 - 11:08 AM
Troul Hawk and Bravepiper, I have just done a silicone test on RTV, without any release agent and to my surprise, it did not stick! On other tests that I did on other materials with Pam oil, the silicone went through the oil like it wasn't there and stuck hard. So, yes the RTV works with silicone. That would give a better finish.
I think the most important thing, or what I am looking for is a flexible eye. I'll try the link later, my line is very slow at the moment.
Posted 02 January 2008 - 01:10 PM
Vodka,Hawk is right I used epoxy for the eyes and when flexed,the eyes fall out of the dimples.Epoxy was so-so as far as the material to use...Still looking.
Posted 02 January 2008 - 01:24 PM
Great ideas Guys . Who says you cant teach an old dog a new trick. This site is great !!!! I'll have to give it a try............just as soon as I wake up from my afternoon nap
Posted 02 January 2008 - 02:16 PM
How about a thick brew of Propionate or DN poured into the mold- when these dry they shrink and Dn remains semi flexible, I think you would finish up with that concave back also. Dn and some Prop is also super clear and 'left overs' could be used here.
VM- again, I don't know where you get the time with all these plastic molds, for eyes and those rubber creatures, but you deserve to be 'knighted' for your efforts. pete
Posted 02 January 2008 - 02:30 PM
To get rid of bubbles in Plaster of Paris, use a vibrator (personal massager) strapped to the mold platform. You could borrow the wifes/partners in the daylight hours or as I have done, buy a small 1.5V DC motor $3-4 and glue a small ,offset lead/steel weight on the shaft, works ok- or for excellent 12 motors, pull apart your old VCR or record player, they are full of them. Personal Massagers would probably be the best , with variable speeds, but you can always add a dimming device to a 1.5V or 12 V motor (car dash light dimmer works) and have the best of both worlds.
Another one (I'm on fire here) instead of Plaster of Paris, use 'Gyprock' ('Rockboard' there I think) top coat, its very fine , slow setting and does not shrink as much as Plaster of Paris. pete
Posted 02 January 2008 - 02:39 PM
C'mon Pete.............personal massager
Posted 02 January 2008 - 08:43 PM
Yes, Pete that is alternative to plaster, quick setting drywall compound works good!
Posted 03 January 2008 - 07:34 AM
Another possibility is a clear epoxy or resin lens, black card dot and white silicone backing, moulded as above. This gains the best of all the materials, chrystal clear lens and flexible, concave mount.
I am working on the moulds and will report back in a few days.
Posted 03 January 2008 - 12:21 PM
I am getting this mental image in the back of my mind of a discussion starting at Nathan's house, continuing through dinner, and around 3:00am, looking for a Walmart that's open 24 hrs a day. Having found the reuired materials, 5, 6, 7, maybe even 8 TU members from around the world, working to build a bigger, better mold... the new material of choice… you guessed correct, Quikrete Hydraulic Water-Stop Cement because it sets hard in 5 minutes and stops leaks in cracked Plaster of Paris, masonry, or concrete surfaces.
Since 20lbs is the smallest size, we create theQuikrete Plaster of Paris mold ever, filling an area of 7.5 square ft. In desperation, we opt for a 2 part mold with a vacuum tube. Suddenly, around 6:27am, we (the group of 8 has grown to 14) realize that nobody actually brought a vacuum pump with them and in the haste of the moment, pile into Vman’s rented Mini Cooper looking for an impromptu vacuum source. Finally we see a vacuum at a do-it-yourself carwash and all 17 (when 3 others pasted through the breakfast bar and wanted to join the discussion) TU members pile out. A small collection of pocket change is collected, after 15 minutes, we had the $1.50 in quarters to start infernal machine.
We (all 17 TU members and 4 TU wanta’ bes just “lurking” at the carwash) watch in amassment as the new experimental liquid RTV compound, aka: “TU4U RTV” (standard RTV mixed with 3ozs of instant coffee and 1 Gal CPC 1207 Soft Plastic) flows through the 16.2kms of mold passages in .743 nanoseconds (darn, we had factored a design spec <.7 nanoseconds) with out a trace of a leak. We continue to watch the timer count off and at 5.56 nanoseconds, we unseal the mold and remove the top…
Oooops, I must have dozed off and subjected everyone to a dream-state post. Sooorrrry
Posted 03 January 2008 - 12:47 PM
The most alarming aspect of the dream-state scenario is there is no mention of beer or any fermented beverage, Bruce I thought better of you!
Posted 03 January 2008 - 04:30 PM
What do you think induced that dream state.
Bruce. Funniest thing I have ever read!
Posted 03 January 2008 - 04:55 PM
This should be in the tutorials under, "The dangers of painting and clear coating without adequate ventilation".
Posted 03 January 2008 - 05:56 PM
With all the talk of vibrators....vaccumn pumps and alchohol Man I think you can count me out. Does kinda sound like fun though but you have to factor in some females.
I guess this threads gone to hail in a handcart.