Vacuum lid vs compression lid w/ foam

[stranddog]

Hey guys. I've been having a tough time with inconsistent exposures and extremely long burning times with my home made table/hallogen set up and I've been looking at some table top exposure units. I was looking at the X vactor from Ryonet vacuum exposure unit versus just the compression lid exposure unit w/foam piece. Just wondering if you guys have had any experience with either of these units or something like them and if its worth going the extra mile and spending the extra 700 bucks for the vacuum lid. Any help would be great.
25x36" Auto UV Screen Exposure Unit w/ Compression Lid

The X-Vactor Digital Vacuum Exposure Unit 25x36"

[washy21]

I'm interested in this too because the exposure unit is the last item on my list before I 'get started'.

Enquiries I have made suggest that a vacuum unit is the way to go, particularly for work of finer detail. My trouble is that here in the UK vacuum units are hard to source at reasonable (used) prices.

I'm on the verge of really getting stuck in and building my own unit based on a large office desk (as a base). I'm just hanging on though hoping ebay turns something up.

[goodnightsweetprints]

I have had the bare bones Ryonet unit for about 6 months and stack a couple paper boxes on the piece of black foam they supply for compression and it works amazingly well. The work I am doing requires consistent exposure and very fine detail (AKA not punk posters) and it works incredibly. The only bit of frustration I have had is with smaller screens when I was unable to use the big piece of foam as a backer. The black shirt I uses for some reason lets light behind the film. Obviously, the compression/vacuum lids will help but that extra money is better spent on other things in my opinion.

As a side note, my unit showed up with a broken glass top and they covered the cost of a local glass shop to replace it. A month later, a bulb went out and they sent me a replacement bulb too. I won't buy ANYTHING from them besides hardware but their service is pretty hard to beat. Watch for specials--they were selling this unit for about $300 off in December.

[strawberryluna]

We went fully DIY and built very heavy blocks out of multiple pieces of MDF, all cut to the same custom size to fit inside of a screen, with foam attached to the bottom and then the entire block is wrapped in felt on 3 sides, with cabinet door handles on the top so that they are easy to pick up, move, and place on the exposure glass.

MDF in stacks of 2-3 pieces is heavy as hell. A little industrial foam to prevent sharp edges and then a tight wrapping of felt = perfect. No problems with fine detail. The blocks are always way larger than the art being burned, but are sized to fit on the inside dimensions of my screens.

We built the exposure unit too, for about $200 in total.

[goodnightsweetprints]

Dang! Great idea!!!

It amazes me how much money the 'extras' on exposure units cost.

Don't be fooled into getting the digital timer by the way. Mine has the analog dial and it is dead-on. If it wasn't, I'd just flip the switch when it went past time.

[Fools Gold]

Night and day . . . vacuum exposure is probably one of the best investments you could make.

[bwiley]

It is night and day. Maybe your situation makes it difficult to build your own, but for $1,500 bucks seems like a lot for something you could build for 1/10th the cost. I've used manufactured single-source exposure units, and home-brew kits, and for the price of a manufactured unit I'd spend my money on other things...

[Andymac]

i thought fancygoat or someone put up some pics a long time ago for a cheapass vacuum top. Wood frame, a sheet of 3-4mil closed cell neopreme attached (wet suit material), some car door edge strip to seal it, a flange in the corner to hook a vacuum cleaner to, and you are done. You want to get fancy, get a real vacuum pump, but that will cost you $3-400.

compression lids will give you 80-90% of the same result as long as you are getting good contact. if you are not doing fine line or halftones, it's good enough. I used the Coronado exposing unit, they do really fine detail stuff, they just have 3 foam pads with black cloth, 3 different sizes. You place the pad on the screen and film, which is sitting on glass, then close the lid. the lid squishes the foam and compresses the glass/emulsion/foam. If you spend more than $30 making the lid and foam, you are doing it wrong or not much of a scrounge.

Re the question of safety....wire it bad, it might catch on fire. put a hot lamp (halogen or metal halide) close to glass it will crack it. flourescent tubes don't give off much heat, so they are safer, but all that wiring....hope you know what you are doing.

[stranddog]

thanks guys. I think its best to just got the DIY route.

[edwardo_machino]

I use an old blanket and put bricks on top of it to weigh down (exposed from bottom). I print some pretty fine fucking stochastic dots and they all come through.