Vacuum Frame Question

[MCohn]

I’m in the market for a vacuum frame, and looking online I came across these: https://www.dennis-ramos.com/portable-vacuum-frame. Does anyone know anything about them? Are they any good? The price seem right (from what little I know). And if anyone knows of a better, similarly affordable option, I’d be eager to hear it. (The Edwards Engineered ones are very nice looking but wayyyy out of my price range.) Thanks!

[Jim Jones]

I worked several years at making half-tone duplicates up to 32x40 inches on vacuum frames. The original and copy were sandwiched between fairly thick glass and thick strong air-tight fabric. This allowed a working vacuum of about -25 PSI. The frames linked to in the original post appear to work at a much lower vacuum, which would limit the closeness of contact between original negative and copy. Perhaps it suffices for copying continuous tone negatives, but half-tone copying with large UV light sources demanded very close contact. Upon second thought, the porous nature of alternative prints should permit much less vacuum for adequate draw-down.

[Drew Wiley]

Remarkably little vac power is required if there is no leakage around the perimeter. Depends on the efficiency of the frame design. A more common problem is too much vac drawdown. Too powerful a pump requires a bleeder valve - a good feature in any event.

[Kiwi7475]

I have the medium one. Works well, I use it to make 11x14 carbon prints. I have no real complaints. The vacuum is sufficient although not amazing, but you don’t need much to make good exposures; the pump requires adding oil frequently as it leaks. This has nothing to do with the seller, most cheap pumps will do that but I have no desire to upgrade it.

[Duolab123]

That's pretty neat. No glass definitely would help with UV

[esearing]

Consider this - Noisy oil splattering energy consuming pump vs quiet glass contact print frame for a salt print at 30 minutes to 1 hour.

[Tin Can]

I hate those crappy oil filled and leaking Air Conditioner vac pumps

Garbage!

I agree, use a glass plate leaf spring pressure box

Cheap and simple

[Drew Wiley]

Quiet Oilless vac pumps have been around a long time.

[Tin Can]

I use one


Quiet Oilless vac pumps have been around a long time.

[Drew Wiley]

There were millions of them made for industrial line applications. The ones adapted for graphics applications were just a small percent.

[Tin Can]

I have a Nuarc Vac frame with perfect OE glass and OE rubber seal full of good holes

My Nuarc vac pump came with a vane kit, my glass bottles are very clean, the bleed off works fine as proven by the vac gauge

I have the pump hooked up with stiff vac hose. The pump switch is mounted on the wall in easy reach, the pump is quiet

I usually have it under a 5X7 Enlarger, but it moves easily

I have all parts for a 20X36" 1/2" tempered glass ALT contact printer with 365mm LED lamps

I have a dedicated bench for it

I like to plan ahead and can prove it with pictures

[Drew Wiley]

I no longer use vacuum pumps, though I have them in storage. I do have several high quality domestic made oilless compressors from the same outfit that now makes those pumps only for industrial vac lines. My current drawdown vac easel system is based on plug-in hose ports on the wall, with the vac isolated in another room. All high quality stuff, variable-power, bleeder valves, HEPA filtered air going out, quiet if needed. Footswitch triggered at the workstation. My two largest vac easels handle up to 30X40 inch paper. But I don't do any UV work.

[MCohn]

Some cursory googling shows a fair number of reasonably priced ones for sale on Amazon and the like. Obviously, something that doesn’t leak oil is appealing. But what should one look for in a pump? Is there a minimum amount of power, or will essentially any of them do?

The point about traditional contact printing frames is well taken—and indeed, I currently use an 11x14 split-back one. But I’d like to go larger, and I’m not convinced they can generate enough pressure, hence my original question about the vacuum frames.

I appreciate the feedback. And certainly envy some of your setups!

[Erik Larsen]

This is what I have used and is what is in my Nuarc plate burner. It’s a diaphragm oilless design. Those pumps shown in your original post work good also but you will need to install an oil mist filter on the exhaust which will cost about as much as the pump. Without the filter a fine mist is exhausted and unless the pump is in another room or preferably outside you’re living and breathing oil mist. I’ve never used a frame like the one you linked to but it looks like it could work fine, my only concern would be poking a whole in the membrane or how to safely clean and dust the membrane without scratching it up?
https://www.ebay.com/itm/163632269458?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=163632269458&targetid=1263433204294&device=c&mktype=&googleloc=1014526&poi=&campaignid=14859008593&mkgroupid=130497710760&rlsatarget=pla-1263433204294&abcId=9300678&merchantid=6372274&gclid=Cj0KCQjw1N2TBhCOARIsAGVHQc5Y-_-76TcGxADIZfA1pj9E7wvpnyC7_jb7uvvnNsc2oJZI2R1A9PwaAjXOEALw_wcB

[Drew Wiley]

Amazon and the like - you me the toy store? Unfortunately, good pumps aren't cheap, but might turn up quite reasonable on the used market under Graphics Supply and Industrial listings. You can get good diaphragm pumps from an outfit like Grainger fairly reasonably. But they do pulsate, so I'd never use them for a vacuum easel below and enlarger column, at least for fussy work (been there, done that). Might be fine with a contact frame.

[aaron_mcfarlin]

Seeking some clarity/consensus on this topic.
I'm considering building one of these frames myself, similar to what Dennis Ramos is selling. The construction seems easy enough, and the material cost relatively inexpensive. But I'm stuck at this point of the pump.
1. The thought of oil vapor spraying everywhere and into the air and breathing that, if this is really true, then that turns me off. Can someone verify that these should really only be used outdoors, or perhaps inexpensive ways to keep it out of the air?
2. The proper pump to use seems to be an oilless rotary vane such as ones made by Gast. But new ones are too expensive for me, and I can't seem to find any cheap second hand ones.
3. Someone here recommended a Cole Parmer Air Cadet 7530-40 which can be had for cheaper, but that i think is a diaphragm pump. Several suggested NOT to use diaphragms due to pulsing or vibrating; but it's not clear if thats more of a concern for vacuum easles rather than for vacuum frames, and that these might be ok for vacuum frames. Any one can confirm that a diaphragm pump such as this is ok for frames?

[Tin Can]

Buy the $50 one now on eBay

[Tin Can]

OK looks like you bought the $500 pump for 10%

Use automotive VACUUM hose from auto parts store

I would add a cheap vacuum gauge and a way to adjust it, called a bleed off valve, the car parts guys will have no idea

This is too expensive, go eBay https://www.amazon.com/Control-Devices-Brass-Vacuum-Relief/dp/B0081TJQVQ/ref=sr_1_21?crid=OGN2ZY211GPY&keywords=vacuum+bleed+valve&qid=1661289066&sprefix=vacumn+bleed+valve%2Caps%2C77&sr=8-21

[Drew Wiley]

Poor man's bleeder valve : just use a Y to branch off from the vac hose a section of smaller diameter tubing that goes nowhere except into the air, and that will reduce the pull force. Fifty cents of common vinyl tubing at the hardware store, and maybe another buck for the brass barb fitting.

[aaron_mcfarlin]

Thanks for all the help guys (gals?)! The pump is on it's way. I'll let y'all know how it goes.