Anyone ever build a vacuum easel?

I want to build one that is strictly vacuum with no glass on top for copy stand use. I was going to use perforated sheet steel for holes. They have a 1/8 or 3/16 inch hole option on the steel. Some companies have smaller holes. I'm thinking 1/8 should do it. I plan to mask off areas with plastic that are not being used to increase suction. I will use a shop vac for suction. Frame to be wood. I may have to use some metal strip in the center to support the steel sheet. Will have to see how much it sags.

I was thinking of 24 x 24 inches, but may go 18 x 24 to increase suction. Steel comes in 24 x 24 as standard size. If you want max suction the best would be to build specific size easels. But it is time and $$, although the payment is mostly time as the smaller you go the cheaper it is and $$ is not a big deal. I'd rather buy one instead of making one as long as it was affordable. But all these old school tools are slim pickings trying to find them to buy.

Here is one like we used back in the 1970's for graphic arts use. Ours was bigger and more robust. It was on a stand and swiveled for vertical use with process camera or horizontal use. They were called vacuum frames. The glass did not heat in them. They were not hot presses.

https://www.bhphotovideo.com/c/product/1190287-REG/drytac_hgp360_hot_press_heated_glass_top.html?ap=y&ap=y&smp=y&smp=y&lsft=BI:514&gclid=CjwKCAjwxuuCBhATEiwAIIIz0dy9-SOcFEBlb25UvFhqGcp3TS1_nnlJiUNJ5Yf8SyCy74G58boykBoCoiUQAvD_BwE

They had an old thread at Large Format forum on a home built vacuum easel. Sadly, all the links are dead.

Here is some videos on YT.

https://www.youtube.com/results?search_query=vacuum+easel

I had built a vacuum easel when I was a kid, but it did not work good. The holes were far apart and too big.

I want to build one that is strictly vacuum with no glass on top for copy stand use. I was going to use perforated sheet steel for holes. They have a 1/8 or 3/16 inch hole option on the steel. Some companies have smaller holes. I'm thinking 1/8 should do it. I plan to mask off areas with plastic that are not being used to increase suction. I will use a shop vac for suction. Frame to be wood.

 

I was thinking of 24 x 24 inches, but may go 18 x 24 to increase suction. Steel comes in 24 x 24 as standard size.

 

Here is one like we used back in the 1970's for graphic arts use. Ours was bigger and more robust. It was on a stand and swiveled for vertical use with process camera or horizontal use. They were called vacuum frames. The glass did not heat in them. They were not hot presses.

 

https://www.bhphotovideo.com/c/product/1190287-REG/drytac_hgp360_hot_press_heated_glass_top.html?ap=y&ap=y&smp=y&smp=y&lsft=BI:514&gclid=CjwKCAjwxuuCBhATEiwAIIIz0dy9-SOcFEBlb25UvFhqGcp3TS1_nnlJiUNJ5Yf8SyCy74G58boykBoCoiUQAvD_BwE

 

They had an old thread at Large Format forum on a home built vacuum easel. Sadly, all the links are dead.

 

Here is some videos on YT.

 

https://www.youtube.com/results?search_query=vacuum+easel

 

I had built a vacuum easel when I was a kid, but it did not work good. The holes were far apart and too big.

Lots of info available online, including videos. - search with this diy vacuum easel for copying.

Never built one, but used a few.

Holes in those commercial versions were about 1/8" diameter and roughly 1/2" apart.

Only advice I can give is: Get yourself some ear defenders!

Those darn things are noisy, and you need a powerful pump unless you find some way of blocking off any unused holes.

I've also got to ask; what's wrong with a glass-fronted frame?

One of the places I worked did highly demanding copying for the aerospace industry. The copyboard used was about 6 foot across and glazed. Lit by 4 tungsten-halogen lamps on swing arms to provide front or rear illumination. Never any issue with reflections or uneven lighting.

However, the back of the massive 'Littlejohn' copy camera did have a vacuum platen.

Here's a plan you might wanna look at... Not metal, and you gotta drill your own holes, though. Minimal tools needed; looks like they designed for simplicity of construction. Presumably it's been tested, but I dunno. Best of luck...

Low-Cost Tilt-Top Vacuum Table

Some 20 years back (when I was an assistant director of a university Historic Preservation program), we were confronted with the need to photograph and digitize large historic maps and old architectural drawings.

To solve the problem, I built a 4x6' frame out of 1"x4" pine. It was fronted with masonite pegboard sheet material (9/32" holes) and solid masonite on the back. Several pieces of 1x4 were placed at 1/3rd spacing to prevent any bowing. On the right side, a 3" hole was cut to accommodate an accessory fitting for a small shop vac hose attachment. On the opposite side, another 4" hole was cut and a piece of masonite was cut with a long center groove (to allow sliding) over the hole. A light sanding of the surface is helpful to reduce bumps--but it is best to work with an aperature of f5.6 or so to eliminate any alignment issues.

The hole with the sliding baffle allowed an adjustment of the vacuum level to the front, perforated face. One must be careful with such a thing to reduce vibration to the entire body caused by the vacuum. It worked, and I figure it could be scaled to most sizes.

Thanks, Bill C

Another example of why it's worthwhile to browse Wilhelm Research (Wilhelm Imaging Research)

Thanks, Bill C

 

Another example of why it's worthwhile to browse Wilhelm Research (Wilhelm Imaging Research)

You're quite welcome (and also clippingphotoexperts).

As a note, Henry's design uses a black front which ought to minimize problems with "print through," by which I mean the situation with thin paper, like newsprint, whereby copies could be affected by what's on the back side of the paper. (If black print shows through, then backing the entire thing with black hides it.)

Many years ago (we are talking 1970's here !), I wanted a 20x16 borderless enlarging easel. Unable to afford new (according to SWMBO), and with no easy second hand market in those days, I created one using a sheet of hardboard, painted pale grey to make it easier to see the printing paper, supported beneath with 1/2 x 1/2 battens, which also provided, on two sides of the top, a corner for the paper. This was OK, but the paper did tend to ripple slightly, so I used some double sided carpet tape (guaranteed not to suffer from adhesive creep) to keep the paper in place - strips (2" wide) along the edges, and a square of strips towards the middle. First attempts were not a great success, as the adhesive was too strong, but an application of Patchouli talcum powder (well, it was the seventies !) lessened the tackiness while still restraining the paper. Worked quite well - when I could afford the paper !

Bill C's mention of print through and using black to prevent it - when scanning from a newspaper or magazine, I slip a sheet of black card under the page I wish to copy, to eliminate this - may be of help to someone.