New to me Olec 5k - need quick help

[IntegrityShirts]

According to these calculators you only need 12# to go 50ft with 24amp draw at 208v or 240v

http://www.jhlarson.com/resources/wire-size-calculator.html

http://www.paigewire.com/pumpWireCalc.aspx?AspxAutoDetectCookieSupport=1

a 24amp draw according to the NEC charts would require a 30amp breaker... the minimum 'rated' gauge would be 10AWG, up to around 100 feet, at which point you may have to start de-rating the wire and go with a lower gauge, depending on how well the load will tolerate voltage drop.

Good point. Adding 20% to the amp load for those calculators yields 10gauge copper for 50' run.

[markdhl]

Douthitt does stock all the parts for that light unit.  The distance back will vary on which reflector and how many screens you are exposing at once.  Rule of thumb with the Superwide reflector ($395.00 includes inner reflector and outer reflector and new bulb holders installed).

With the superwide reflector you want to be back .6 of the diagonal of your screen(s) OD.  With a standard reflector in good condition about .75 back from the diagonal.

The old 1.5 times the diagonal is from the old dark room film days and not applicable to exposing screens.

It is very important to make sure your voltage selector switch is set in the proper position (wrong position can damage components or cause long exposure times).

For technical questions, call or email me anytime direct since I am not on the board too  often.

Mark Diehl
313 515 8635
Douthitt Corporation

[Frog]

Wow! Only a 15% difference in distance between the two different reflectors. That's hardly anything on the screens we use.

[ZooCity]

Double thanks.  I didn't realize this was the service manual, good to have on hand.

[markdhl]

If you were doing larger screens the superwide become much more important.  No matter what reflector you use be sure it is clean (alcohol wipe) and still shiny.

Inverse square law of lights does make 15 % a bit more important for shorter exposures but not critical.

[ScreenFoo]

MimTX:  Just check continuity from ground to the chassis with an ohmmeter on the lowest range.

It just ensures that if there is a fault, loose wire, or short circuit that the breaker will trip instead of the chassis becoming 'hot' (i.e. electrified).  With the kind of voltages in those power supplies, you do not want the chassis hot.

If you're not familiar with safety grounds and are trying to learn more about electrical, it's a good subject to start with.
https://en.wikipedia.org/wiki/Ground_%28electricity%29

[mimosatexas]

Everything is up and running and amazing.  In the process of exposure testing now.

I'm a little concerned about my integrator though.  It is a Magic 83. I followed the calibration instructions in the manual and everything is working exactly as it supposed to, but I am running diazo emulsion on frames that have a diagonal of 70+ inches, so my lamp is about 54 inches from the glass.  The issue is the integrator only goes up to 99.9 and the instructions had me basically calibrate so one light unit equals a second, but it is looking like I need a longer exposure.  Does anyone know how to calibrate it so a light unit is something like 10 seconds instead?  the SP1400 has a pretty huge exposure latitude when it comes to going over, so I am not really concerned with getting it down to tenths of a second (lol).

edit:  Also, does anyone have any "best practices" when it comes to these things?  I tend to batch screen making into long single sessions.  Is there any issue with the unit being on for a few hours at a time?  All fans seem to be working etc, but it is still pretty hot to the touch on the lamp assembly after a while.

edit2: looks like 240 light units (about 4 minutes) is close to the sweet spot currently.  I'll move up the unit when doing standard screens, or possible shoot 2 or 4 up depending...

[mimosatexas]

Figured out how to make one LTU = 10 seconds!  Everything is working awesomely now.

Now to send off a film and shirt to Pierre to get everything calibrated!

[markdhl]

Also on the Magic 83 you do not need to use the decimal.  Use the 1/10 button to eliminate that and then goes up to 999.

If you are ganging up screens, you may find it a lot faster to do less at a time. Inverse square law of the point light.

Mark Diehl
313 551 8635

[mimosatexas]

Great tip!  I'll recalibrate it today.  I was wondering why it felt limited.  I'm still trying to figure out the best way to shoot big screens vs my standard shirt screens.  Right now I'm leaning toward making a small wall mounted vacuum frame from my current floor unit (already a DIY build) and just turning the light 90 degrees when shooting one type vs the other.  My large frame is fine for large frames, but for shirts I want the "pros" of my current smaller unit: thinner glass, better vacuum, easier to handle etc.  Plus I think I'll be able to have the light about 24"-28" from the glass which would end up at around a minute per exposure.  That would keep my exposure process nice and streamlined with no waiting times.

[Frog]

Great tip!  I'll recalibrate it today.  I was wondering why it felt limited.  I'm still trying to figure out the best way to shoot big screens vs my standard shirt screens.  Right now I'm leaning toward making a small wall mounted vacuum frame from my current floor unit (already a DIY build) and just turning the light 90 degrees when shooting one type vs the other.  My large frame is fine for large frames, but for shirts I want the "pros" of my current smaller unit: thinner glass, better vacuum, easier to handle etc.  Plus I think I'll be able to have the light about 24"-28" from the glass which would end up at around a minute per exposure.  That would keep my exposure process nice and streamlined with no waiting times.

most folks with this light have it mounted on its wheeled stand with marks on the floor corresponding to the size of the area to be exposed

[mimosatexas]

I marked the floor for both my large frame and the light unit (it is on wheels).  My large vac frame isn't ideal for shirt screens though.  The glass is very thick and there are some random scratches on it, and the blanket is pretty beat to hell.  It works GREAT for what I need it for (flag printing), but not so great for the 55lpi stuff.  Also just a lot more work to load, vacuum, flip, etc than a small frame will be.  I'm literally going to chop the legs off my current unit and drop a bolt on each side and make it flip-able.  I actually already have a wheeled "cart" that will only take one 5 minute modification to hold it up at the right height.