Home made vacuum fame plans and a question

[mark]

At some point on this site someone posted their homemeade vacuum frame. I am looking for plans.

Vacuum pumps are expensive and noisy. I was wandering if a modified foot pump and close off valve would do the job just as well as an electric pump? I was also wondering if anyone knew what kind pressure is needed to ensure ultimate contact?

 

[richard ide]

Hi Mark
As I recall anything over 20" on a vacuum guage was OK. I would always wait at least 15 seconds beyond that before exposing in a small frame and up to a couple of minutes with my big frame (high volume pump and 66" x 96" glass size). The material behind your negative and print can also make a difference. I bought an Agfa colour print system which included a vacuum frame which used a thin polyester sheet instead of glass and the pump looked like an aquarium air pump but used in reverse. Not very high vacuum but it worked. With the plastic curtain, a rubber roller helped a lot. Withy any of them vacuum was broken when the pump was turned off so I think a foot pump and shut off would not be satisfactory.

 

[Luseboy]

I got my vaccum system with an enlarger and a bunch of other stuff that i was given. One is a home-brewed wooden guy that's basically a wooden box with one side being that type of board that has holes in it (for storage and organization stuff, i forget the name), and one of the sides has a hole in it for the vaccuum tube. The other board is best described as a portion of an air hockey table. They both work well, and i have used them quite a bit. The thing with using vaccuum boards is that you have to mask off the vaccuum where the paper isn't so that you don't lose pressure. Also for a vaccuum motor, just keep your eye out at garage sales/etc. I was just looking online, and walmart sells a small shopvac for 25$. This would be a good option because the shop vac will have a good amount of power. The vacuum that i currently use is a beseler "blower" which was an accessory for the dichro heads. The guy who used it for vaccuum board stuff had flipped the polarity on the motor so it is now a beseler "sucker". Unfortunatley, i find it doesn't have enough pressure, particularly for fiber paper. However it does work ok for RC paper. I plan to pick up one of those wal-mart shop vacs soon, to use that. I will report back on how it performs if you'd like.
-Austin

 

[mark]

Sounds like the vacuum motor would burn out.

 

[Luseboy]

Sounds like the vacuum motor would burn out.

with what? If you're reffering to the cheapo wal-mart shop vac, i wouldn't think so as you really wouldn't be using it for as harsh things as it was designed for. and for the beseler "sucker" that i have, well i believe that the previous owner did this about 20 years ago. It still works great.
-Austin

 

[Bruce Osgood]

At some point on this site someone posted their homemeade vacuum frame. I am looking for plans.

Wasn't me but this is what you are referring to:

Dead Link Removed

 

[tim k]

I built one a short while ago. Just used a shop vac, that sits in another room. Works great. I have no plans but its pretty simple, just a piece of plywood covered with formica, with a little hollow space below.

 

[Steve Roberts]

I have use a vacuum frame that I made myself. My darkroom/dark cupboard is upstairs and so the vacuum part of is provided by a conventional vacuum cleaner that sits in the loft so that the noise doesn't drive me mad and the "exhaust" doesn't stir up dust. My baseboard is 12" X 10" aluminium plate, in which I drilled (very laboriously) holes of about 2,5mm dia. on (I think) a 1cm grid. It works very well, and even when only using postcard size paper there's no need to mask off the unused area to maintain sufficient vacuum.

Steve

 

[DanielStone]

some of these "frames" look more akin to an easel(for keeping a piece of enlarging paper flat) rather than a vacuum FRAME(which sucks a negative and paper together).

I got mine(18x22" Nuarc) w/ a pump from Craigslist for $50. I had to re-wire the cord with a new one and a new plug, but it runs like a champ and pulls about 35# at full force, probably more if the gauge wasn't topped out already . So all in all with new parts, about a $65 investment.

-Dan

 

[tim k]

some of these "frames" look more akin to an easel(for keeping a piece of enlarging paper flat) rather than a vacuum FRAME(which sucks a negative and paper together).
-Dan

Dan, you are absolutely correct. My bad for not really paying attention.

 

[DanielStone]

no worries Tim,

they've both got their uses, and both are very helpful at keeping things flat

-Dan

 

[holmburgers]

Something I've always wondered, how can a vacuum frame keep a paper flat and the negative flat? It seems that no suction would get to the negative, unless it was much bigger than the paper and had vacuum holes around the edges??

Confused in Kansas,

 

[jorj]

Something I've always wondered, how can a vacuum frame keep a paper flat and the negative flat? It seems that no suction would get to the negative, unless it was much bigger than the paper and had vacuum holes around the edges??

Confused in Kansas,

The frame sucks a rubber or vinyl membrane against glass, with the paper and negative between the two.

I had similar questions until I dove in and built one myself from two large picture frames, a piece of glass, a sheet of vinyl a vacuum pump, a pack of weatherstripping, some rubber tubing and a stapler. I've subsequently added hinges. Fairly economical, works exceedingly well.

-- Jorj

 

[holmburgers]

Thanks Jorj,

This brings me to my next question... what is the advantage over a standard contact printing frame, since there's still glass in the path?

 

[mark]

Good question. I think it is perfectly even contact between paper and neg.

 

[Steve Roberts]

Something I've always wondered, how can a vacuum frame keep a paper flat and the negative flat? It seems that no suction would get to the negative, unless it was much bigger than the paper and had vacuum holes around the edges??

Confused in Kansas,

That's easy - holes in the paper!!!
Steve

 

[greybeard]

If you use a vacuum cleaner as a pump, make sure that the motor has its own cooling air (as do most or all shop vacuums) instead of blowing the air from the filter bag through or around the motor. In the latter case, operating for too long without airflow may overheat the motor. This would be particularly bad if the thing was in another room to isolate the noise (and, eventually, smell of burning insulation...)

 

[jorj]

Good question. I think it is perfectly even contact between paper and neg.

Right. For small prints it shouldn't make any difference one way or the other. I like to print ~17x22, and the vacuum frame gives me perfect contact between the negative and paper.

 

[Leigh B]

some of these "frames" look more akin to an easel(for keeping a piece of enlarging paper flat) rather than a vacuum FRAME(which sucks a negative and paper together).

Dan,

Vacuum FRAMEs are commonly used on process cameras to hold the original in firm contact with the back of the glass, ensuring its flatness.

The film in this case is on the other side of the lens/shutter.

- Leigh

 

[olleorama]

Hello. I haven't used a vacuum frame or easel. But I have built my own pump for laminating composite stuff in a diy project (don't ask..) I used an compressor from an old refrigerator. It was rather silent and produced enough vacuum to laminate fiberglass. You can find them in scrap heaps for free or a modest sum. Just a small advice.