Building A New DIY Exposure Unit /// Screen Printing Halftones 

Hey Josh, I have a question, and if you haven't already upgraded this project I have a few recommendations as well. By way of background, I've been using exposure units on and off for decades since I bought my first mercury vapour exposure unit from Nuarc. Would you say that the additional cost of Starphire glass was worth the cost, AND how if so what is your opinion based on? Optical clarity is great for architectural glass and art pieces that are interpreted by the human eye, but since I only care about passing UV light I suspect the benefit is slight or non-existent since I can just increase exposure time slightly to account for lower UV transmission on slightly cheaper glass. The question is how uniform is the UV transmissibility on really cheap glass and will that impact the image quality? I am going to finally make a unit since UV LEDs are now cheap and easy to source. I'll use a power supply and UV strips instead of fixtures and go with a higher LED density and wattage. You should add the following, a 12v 5a power supply, a 12V Timing Delay Relay Module Digital Timer Cycle Delay Switch Module with Dual LED Display and a Single Phase Solid State Relay SSR Relay with input 3 - 32v DC, and output 90 - 480 VAC. The timer will turn on and off the UV light source that is connected to the solid state relay. This provides much greater consistency in exposure and adds about $60 Canadian to the cost, which is recouped for anyone building from scratch by not using super expensive glass. I use my UV units for photographic print processes like gum bichromate, gumoil and platinum palladium

Everything I've been reading about LED lights says they do not give off enough UV to be considered a UV light source. So I wrote off LED an an option. Now I am confused LOL

Could you please tell me more about the 2 kinds of light used in this project? Thanks

I brought a used ryonet 25x36 exposure unit for $200 and converted it to led for $150 it was really easy. You can find then on offerup for cheap.

Hello. I am going to build one myself and this video is very helpful….what thickness is the glass????

Im in the middle of rebuilding an old exposure unit (from the 70-80s). Used to run off 220v and jumped the voltage to 680v at the bulb, to which i worked on a bit ☠️ lol. And im done fixing old tech and need to modernize it with LEDs and a modern controller. Right now i slapped in a 100w 395nm led and two stage switches as to not be able to turn on the led timer without turning on the vacuum at least Long->Short; looking for a good LED source 🙃

Extremely genius, i want to establish screen printing company and your channel will definitely upgrade my skills…please keep it coming Subscribed💯

Hello 👋 😊 can i use acrylic clear instead glass? i have new one i don’t want to buy….i think should work…

Just built this unit and it's everything I needed for halftones and super fine details!

Looking back on my build. I should have bought one. Had the same amount of $ as yours..... But the time. Almost 3 months. Granted I can burn a screen in 10 seconds. But it took me what seemed like forever to figure out the wiring. The light. The distance.... Blah blah blah.

What brand of emulsion do you use?

Great vid, mate! Many thanks - will give something similar a shot!

Would have definitely been better with the inside painted flat black. You don't want the light to reflect at all so it hits the emulsion from a direct angle and not diffused. I was a pre-press 4 color film stripper in the 90's and duped film for a living for 5 years. You want light straight down for your cleanest edges and that's it...

Thank you for the video. Going to tackle this project this weekend. By any chance do you have a link to the hinges you used for the lid?

Hi, I'am french , i have a question. does this work for all types of illustrations? even those with a lot of detail?! I have 90T frames Thanks

Thank you so much for the video!! I'd love to know more about how you did the lid & latch setup! I'm in the process of building a unit, primarily for cyanotype developing, and I'm trying to figure out the best way to achieve good contact pressure without worrying about damaging the glass. Can it handle stacks of different sizes without putting too much strain on the glass? If yes, how so? Thanks again for the very helpful video!

How is the unit working now that you have had some time using it? Is there anything you would change? I’m fixing to upgrade a unit that has fluorescent tubes and would like to get your input on how well it’s doing versus just buying a new unit. Thanks for your input and keep that awesome content coming.

You could have got a professional unit for that price

i had deleted my previous comment about plans after going back and looking at your drawings at the start of the video again but WOW you responded quick. thank you a lot man, earned a sub for sure king

Awesome video. After using your unit for awhile now do you like the LEDs you used and would you make any adjustments now or love how it turned out and worked for you? I am in the process of building my own unit again with LEDs and liked how you made the cover so that it still put pressure over the foam pad. I was also thinking of building mine with a vacuum blanket but not sure If I should wait and do your approach and down the line if I needed to I can add that part later. Anyways love your content and keep up the good work.

Hey I know it's been a while but was that a 40 lpi? Great video!

Have many watts is great for that job screenpriting?

What are your exposure times and what do you use to coat your screens?

Hi awesome video. Where can I find the exact build plan for this exposure unit. Showung exact measurements and Wide and heights from light to glass?

I keep getting told that led lights will only do fine details if it a single point so I don't understand how these lights will work?

how do you reckon acryllic would do instead of glass?

Nice. For an easy timer I just connect to a wifi plug "Hey Google turn my light on for 3 minutes" ✌️

that music man, it's so bad. other than that thanks so much for the video

Hello by any chance can you show you the wiring part because I'm having a hard time?

Is this regular LED lights or UV lights..?

If I buy a low iron glass , but it's got a UV coating on it , I shouldn't use it , as I'm using UV lights and want it to go through ?

Not to criticize your effort, but building an exposure unit is trivial. A real challenge is building an affordable direct-to-screen printer to lay down black ink onto emulsion. This is much more efficient than using transparencies. These machines exist but needlessly cost thousands of dollars.

Awesome stuff. The halftones look good.

Very cool. The link you give for the LED's off Amazon are blacklights. That's not what you used, is it???

Thank you for your video!!! very great job look cool 😎 exposure 💡very helpful Have a good day

Wow, nice job. I’m starting out and trying to figure things out. I have 100 watt led flood light and Get no image no matter how long: 2 minutes, 3,5,7,8,10. Zero image. You did it so quick. Very puzzling.

Anyone know what the hinges on the lid are called?

Nice one bro. I built my A3 UV LED strips E.U for under 50 euros. Exposes in 1min 37secs. Gona upgrade to A2. Defo worth the time to DIY this. Good luck

Have always wondered why we can't use an old projector for an exposure unit. Vacuum screen to film with clear plastic, hang it on the wall, project bright light? Projectors use lenses to concentrate and distribute light evenly. Any thoughts about this?

Does the same plug into wall outlet power both uv lights and safe lights after wiring to rocker switches?

Really cool video man, idk if building one is for me, you did a great job though

its weird that i retro fitted my exposure unit with the same uv leds... yet i use aqua sol hv and my exposure time is 4 seconds?

Could you please tell me your source of the glass you used in unit ? Thank you in advance ?

Hi. this is awesome video. I built one following this and got lights from the link in your video, except I build 20x26 so half the size and got only 4-light pack. I am having hard time figuring out exposure time with pre-sensitized emulsion, 110 mesh and 240 mesh, 1-1 coating. How did you arrive at 40 seconds? TIA for your help.

Would clear glass affect this build?

which emulsion should i use with the 50watt uv if im using plastisol ?

What are your dimensions for the lid? Thanks

Did the lights hold up? Have you had to replace them?

Do you have a link on where to get the foam you put on screen when exposing

bless you this is so helpful. keep printing!!!

pretty cool….. nice build…

Did you bypass the balces or how did you wire the underneath??

Whats up Josh love your channel bro. Exposure unit came out great led is a game changer. Just wondering if your thoughts on the D-100 have changed now that youll have to cure larger prints? I already know its not ideal for large production. Just wonder if you feel youve outgrown it? Because i cant decide between that, the D-1000, the little buddy or the Riley Jr.

how thick is the glass ? great vid btw

Centimetre and feet 🤔🤔🤔

I used a timer from Amazon for mine works great.

Love it! Thanks

2 months 😅

Not sure why I missed this, but I went looking to see if you had made a vid recently and viola... you did! Great job on the build and your getting the same times I got with that emulsion out of my $1300 RH exposure unit. Nice!

Glass 160? Why??

Hi! Thank you for this video! I am just starting out and was looking into making an exposure unit. I was just going to hang a bulb but i think the time for exposure will be a while. Would you recommend this same style for 20x24 screens? Or should I stick to the original one you created? Thanks!

Wow nice 👍

The led bulb is it uv or just normal led white light?

Super !!! Un gros gros merci !!!!!!!

Did you buy the glass from a local supply or online

How far apart did you space the LED strips?

COOL

YES! ☑️☑️☑️

How bad is it to use regular tempered glass?

what's the label maker you used there??

Did you use 1" thick plywood for the outer shell of the box?

can you please tell me website that you get glass..

Hey! What size should the glass be for screens that are 20x24?

Where did you purchase the led light strips?

Where did you get the foam?

Just finished mine using the same LEDs. Should make for a nice even exposure! My box is 30x20 so my spacing was a bit tighter than yours to cram all 8 in there. Thanks for the instructions I appreciate it!

Hi Josh!!! This is the most inspiring video on constructing a DIY exposure unit. You really are terrific. Thank you. I am wondering if you have tried Baselayr Complete emulsion with your exposure unit? I am using water-based inks. Ryonet says that black-lights should not use Complete.

$500 is too much i built my exposure box for only $180 with digital timer and automatic shutoff

Hi Josh. Have you ever experienced saw tooth / poor bridging in your designs? I've built essentially this exact unit and I the first emulsion I've tried is a photopolymer (polycol multi-tex) and while I've read that a switch to a dual cure may give me better detail/bridging... i've also read this style of exposure unit could also be to partially blame. What emulsion do you use? I've tried a wide range of exposure times / degrees of washout aggressiveness and still always see the saw tooth. The only difference between out units is I did not build a vacuum top so I'm simply using a lot of weight on foam. I have 8 of the same UV strips as you under my 24x20 frame. Thanks.