how many screens/gallons of emulsion are you coating?

[blue moon]

We average about 60 screens per gallon of emulsion.  We use the glisten method, round edge of scoop coater, 23x31 screens, mostly thin thread mesh.  I've measured this many times over the years and we've used mostly pure photopolymer emulsions with fairly high solids content and it's always hovered around 60/gal. 

same here.

pierre

[DannyGruninger]

Depending on what we are doing we are around 60 on the low side and 100+ on the high side..... Personally I don't see how direct emulsion would not save you a bunch of $$$ compared to cap film

[Croft]

65 + here using KIWO polycoll crossover $56 a gallon ( really like this emulsion no pinholes ever) mix of 110-230 mesh 23x31, tried the ez orange at a supplier open house really liked the ease of use and had wanted to go from rinse to coated screens but the cost was no where near within 25% as they were trying to sell it.

[alan802]

I haven't done any really hardcore number crunching that I've done for other things in the past when it comes to cap film versus direct emulsion, but I think the film sheets for 23x31 screens would need to be about $1.50 a sheet to be about even with direct emulsion.  And that is assuming the quality of the finished stencil is equal.  I know before the EZ film came out there wasn't anything that could compete with direct emulsion but getting 50 sheets of 30-50 micron film for $100 is getting pretty damn competitive.  A shop that really struggles with coating screens and doesn't have any trouble with cap film may actually save money going with film.  I think if it weren't for the adhesion issues we've had with film I might give it a harder look due to time savings.  We could turn a screen right at the end of the reclaim process saving the time of pouring emulsion into the coater, prepping for a coat job, then the 30-45 seconds it takes to coat a screen.  And then you get into the actual reclaim time and I wouldn't be surprised if it takes half the time to reclaim a cap film screen versus direct emulsion but haven't done any testing on that.  I just know the few hundred cap film screens we've done have reclaimed really fast. 

[Orion]

we use SP1400 here... 

coating 1x1 round edge
typically running around 20-25% eom as measured with a thickness gauge

we get around 70 screens per gallon.. mix of 160S and 225S mesh counts.

cost per gallon = $31.50 == approx 45 cents per screen in emulsion cost.

Same emulsion, same mesh but throw in a lot of 255x and using the sharp edge 1X1.  We get a few more screens than 70.

Found some good comparison info on cap vs. direct....

1. Printed image quality (vs. imaged stencil quality) is superior with capillary films due to the fact that the film is coated onto a polyester carrier. The PET carrier enables the print surface of the stencil surface to dry in a much more flat state than what you can achieve with a direct coating. When you coat direct onto a mesh, as the emulsion dries the stencil printing surface takes on the contour of the weave in the mesh, leaving high spots and low spots. With capillary film, you remove the PET and a smooth, flat printing surface remains. This flat surface provides an "ink damn" on the edge of the stencil when printed, and keeps the ink contained within the image area. When you print through an emulsion stencil, you can actually see where the ink will squeeze out around the open stencil area toward a contact spot on the mesh, causing a distorted image. This is true with most any mesh count, and is the primary reason that ultra high resolution printed images are best when using a film, capillary, indirect film, or direct/indirect stencil system. This distortion in the image is best seen under strong magnification such as a 25x or 50x microscope.

Many emulsion manufacturers try to compensate for the "shrinkage" of the solids around the mesh by increasing the solids content of the emulsion, or recommending a "wet on dry" multiple coating technique, but the true flatness of the stencil surface is difficult at best to achieve with a direct emulsion, vs a film product.

2. In terms of durability, technically the direct emulsion should be more durable than a standard applied capillary film, provided that the emulsion is coated onto both sides of the mesh. Direct emulsions fully encapsulate the fabric when correctly coated and exposed, thus should be capable of higher print runs under similar conditions to a film that is applied to only the print side of the mesh.

Having said that, capillary films are called capillary films, because during the mounting process, the emulsion is softened by the water used and the emulsion is drawn up between the openings in the mesh by capillary action. Although the emulsion does not fully encapsulate the fabric, it is embedded further into the mesh than an indirect film would be.

Under most conditions, you would have a hard time proving one system was more durable than the other under the same conditions.

3. From a consistency standpoint (remember screen printing is all about control of the variables), a film stencil system is the only way to ensure consistency in the stencil with nearly guaranteed repeatability. Capillary films are sold in various thicknesses to ensure consistency in the stencil thickness. When you adhere a 35 micron capillary film to a 200 tpi mesh, your stencil thickness will be nearly exactly the same thickness on every screen. Stencil thickness is extremely important in controling color saturation and hue shifts in halftone printing, as well as controling accuracy of ink laydown in UV ink printing.

4. Both systems should be easy to reclaim using the correct ink wash and stencil reclaiming techniques recommended by the manufacturer.

5. Capillary film, or other stencil film system would benefit most all printing applications. Each film system has specific benefits and drawbacks, but in most cases, will provide a superior printed image under similar conditions to direct emulsion. During the early to mid 1980's, most screen printing companies around the world were using a film (capillary or indirect) for their stencil imaging. Emulsions began to take hold in the market in the late 80's due to sensitizer improvements, providing better image quality and other features.

You should explore the benefits of using an indirect film for your glass printing application also. Although the durability of an indirect film is not as high as either a direct emulsion or capillary film, there are indirect films that will allow you to go from exposure to printing within 15 minutes! and still provide controlled ink deposit, high resolution and definition images (2 mil lines, 2 mil spaces with some films), and consistency in stencil from screen to screen.

[Shanarchy]

I haven't done any really hardcore number crunching that I've done for other things in the past when it comes to cap film versus direct emulsion, but I think the film sheets for 23x31 screens would need to be about $1.50 a sheet to be about even with direct emulsion.  And that is assuming the quality of the finished stencil is equal.  I know before the EZ film came out there wasn't anything that could compete with direct emulsion but getting 50 sheets of 30-50 micron film for $100 is getting pretty damn competitive.  A shop that really struggles with coating screens and doesn't have any trouble with cap film may actually save money going with film.  I think if it weren't for the adhesion issues we've had with film I might give it a harder look due to time savings.  We could turn a screen right at the end of the reclaim process saving the time of pouring emulsion into the coater, prepping for a coat job, then the 30-45 seconds it takes to coat a screen.  And then you get into the actual reclaim time and I wouldn't be surprised if it takes half the time to reclaim a cap film screen versus direct emulsion but haven't done any testing on that.  I just know the few hundred cap film screens we've done have reclaimed really fast.

I'm at $105.05/50 ($2.10/ea) but I believe Tech Support is having a 20% off show special which would bring me down to $1.68/ea. I think I'm going to continue this route for now. Probably take advantage of the sale and really stock up. Keeping reclaim and coating to the same job definitely offers operating cost savings. It also will allow for me to not need as many screens as we can turn them over quicker. It's also been real simple to train my part timer(s) to coat screens. We are a very small volume shop (probably the smallest on here), but as we continue to grow I need to keep reviewing this one. When I get to Dave/Bimmrider's size and doing 150 screens a day, that would be an additional $58,000/yr difference.

I'm going to look into permanent block out to get rid of the time and money on tape next. But I'm sure no one wants to talk about tape on here. 

interesting tidbits on Orion's post.

[Gilligan]

I could challenge you on that lowest volume shop title.

[Frog]

I could challenge you on that lowest volume shop title.

If time spent on here is indicative of free time, you are certainly in the running.

[Shanarchy]

I could challenge you on that lowest volume shop title.

If time spent on here is indicative of free time, you are certainly in the running.

Zing!!! 

[Gilligan]

As said, I'm more of a marginal consultant in my shop.  My guy runs the show and I only step in to problem solve or to tell him how I think he's doing it wrong.

[Itsa Little CrOoked]

I decided to update my post on this thread.  Weird quoting myself, but for convenience, from page 1:

WR 25 sharp edge 2 over 2. I've not figured how many screens exactly since moving to an auto. I used to get 120 per gallon of my normal mix of manual screens. 110, 156, 195, 230, and 305. With the bulk of them being 156 and 230...all standard thread thickness. I'm going to guess I'm in the ~75 yield now, of 23x31's per gallon.


I just finished a count on only 23x31's. Usually I do a mix of auto and manual screens.

Anyway, 75 is a little high...lets call it 70--on the high end. I could only get 75 if I did it all em one session with zero waste...which never happens.

I think I get a few more that the 60 that several posts indicate, is because I use the sharp edge. I just can NOT get the hang of the round edge! It isn't consistent for me.

Another thing I do is I switch up the direction of coating with each stroke. It is for pinhole management, and it may just be all in my head.

I coat the shirt side for 1st stroke, flip the screen (top to bottom) for stroke 2, Spin the screen to the squeegee side for the 3rd pass, then "bottoms up" again for the 4th pass. All sharp edge, all the time. Some habits are hard to break.

[CSPGarrett]

I have doing a new calculation the last 3 days on a gallon I opened just for 125 mesh screens (I use a lot of them).  Santi PV with a 1/1 round coat with a really slow coat.  So far at 30 screens and I am guessing I will end at 60-70 total. 

This includes scrapping all I can out of the gallon at the end AND using it all.  That is totally fine with me for auto frames, since moving to Ulano Orange next it will be $0.50 on average (less if we go 71+ screens).

I always calculated $2.00 per screen for film, uv ink, and emulsion so it is good.