DIY Light Table

[Laurent]

A friend of mine made one for me. He was making neon signs and just used some used ones to make the thing. It works fine, costed nothing...

It may be a gold mine for DIY if there's such a company near your home, they usually have tons of used signs, and the box itself makes a very neat table, even if you have to fix the tubes and change the panel.

[donbga]

I built a light table for a geologist friend to sperad his maps on, it was 3x5' and I used a piece of 3/8" sandblasted glass. Its strong, self supporting and when sandblasted quite uniform illumination. I put flurescent lights underneath, and had the top hinged to allow access for changing the bulbs. I can't recall the cost of the glass, but I went to a commercial glass shop and it wasn't that expensive.

Craig,

Excelent suggestions, 3/8" glass should be plenty strong.

Thanks,

Don Bryant

[David Ruby]

LED are quite expensive still, and very point source. You could use them, but you'd really have to make sure the glass could diffuse the light well enough for you.

[argentic]

I'm not sure if this is the best forum to post this question but does anyone know of any sources for building a light box roughly 3x4 feet in dimension?

Don Bryant

Just a hint. Sometime ago I bought a viewing table for X-Rays very cheap ($ 30). It turns out to be the best light box I have ever had, with very even lighting by four 6000 K tubes. I would have never been able to make such a quality lightbox for so little money myself. I think in the medical business they are called "negatoscopes".

[Shesh]

I'm not sure if this is the best forum to post this question but does anyone know of any sources for building a light box roughly 3x4 feet in dimension?

Don Bryant

Don,

I built a light table for myself and here are the details: The surface dimentions of the light table are 20"x48". The depth of the box containing the tubes is just short of 7" and the tubes are located along the base. The 2 tubes are placed at approximately 1/3rd and 2/3rds positions. Before you finalize the positions of the tubes, place the glass and acrylic on the light table, switch off all the surrounding lights to make sure you do not see any dark patches. reposition the tubes until you are satisfied.

By far the most expensive components of the light table are the acrylic and glass sheets. Before you decide on the final dimentions, ensure that tubes with the right color temperature are available in that size.

a. 2x4's = 30" x 4 nos. (legs)
b. 1x6's = 48" x 2 nos. (border between legs and light box)
c. 1x6's = 20" x 2 nos. (border between legs and light box)
d. Wheels x 4 (To help move the table around - This thing gets heavy after the glass and acrylic sheets are added)
e. particle board (3/4") = 48" x 20" x 1 nos. (base of light box)
f. particle board (3/4") = 7" x 48" x 2 nos. (sides of light box)
g. particle board (3/4") = 7" x 21.5" x 2 nos. (sides of light box)
h. 1/4" Glass = 49.5" x 21.5"x 1 nos. (top of light box)
i. 1/8" White Acrylic sheet = 49.5" x 21.5" x 1 nos. (for diffusing the light)
j. "L" shaped Border to hold the sheet down to the table slightly larger than the dimentions of the table with one of the sides of the "L" being atleast 3/4", preferably 1"
k. Fluorescent light fixtures x 2 nos.
l. Fluorescent tubes - 5000K, 90 CPI x 2 nos.
m. Wiring x 15 feet (with ground).
n. Gloss or semi-gloss white paint for the inside of the box.
o. Paint for the outside of the box.
p. Aluminium foil (slightly crumpled) to line the inside of the box to add reflectance.

Tools:
1. Hacksaw.
2. Drill Gun and bits.
3. Screw driver.
4. Pencil.
5. Ruler.
6. Spirit level.
7. Sand paper.

[donbga]

Don,

I built a light table for myself and here are the details: The surface dimentions of the light table are 20"x48". The depth of the box containing the tubes is just short of 7" and the tubes are located along the base. The 2 tubes are placed at approximately 1/3rd and 2/3rds positions. Before you finalize the positions of the tubes, place the glass and acrylic on the light table, switch off all the surrounding lights to make sure you do not see any dark patches. reposition the tubes until you are satisfied.

By far the most expensive components of the light table are the acrylic and glass sheets. Before you decide on the final dimentions, ensure that tubes with the right color temperature are available in that size.

a. 2x4's = 30" x 4 nos. (legs)
b. 1x6's = 48" x 2 nos. (border between legs and light box)
c. 1x6's = 20" x 2 nos. (border between legs and light box)
d. Wheels x 4 (To help move the table around - This thing gets heavy after the glass and acrylic sheets are added)
e. particle board (3/4") = 48" x 20" x 1 nos. (base of light box)
f. particle board (3/4") = 7" x 48" x 2 nos. (sides of light box)
g. particle board (3/4") = 7" x 21.5" x 2 nos. (sides of light box)
h. 1/4" Glass = 49.5" x 21.5"x 1 nos. (top of light box)
i. 1/8" White Acrylic sheet = 49.5" x 21.5" x 1 nos. (for diffusing the light)
j. "L" shaped Border to hold the sheet down to the table slightly larger than the dimentions of the table with one of the sides of the "L" being atleast 3/4", preferably 1"
k. Fluorescent light fixtures x 2 nos.
l. Fluorescent tubes - 5000K, 90 CPI x 2 nos.
m. Wiring x 15 feet (with ground).
n. Gloss or semi-gloss white paint for the inside of the box.
o. Paint for the outside of the box.
p. Aluminium foil (slightly crumpled) to line the inside of the box to add reflectance.

Tools:
1. Hacksaw.
2. Drill Gun and bits.
3. Screw driver.
4. Pencil.
5. Ruler.
6. Spirit level.
7. Sand paper.

I would prefer never to use particle board as it is unnecessarily heavy. And I have no limit on tools, so it's not an issue for me. Cutting wood with a hacksaw seems to rather difficult at best. Poplar or white pine would be my choice for wood for the side panels. 3/8 inch plywood for the base will be plenty rigid. I think that at least 4 tubes would be desirable. I'm not sure that the aluminum foil adds anything, rather a paint with a high albedo would work fine. Thanks for the suggestions.

Don


Don

[donbga]

Just a hint. Sometime ago I bought a viewing table for X-Rays very cheap ($ 30). It turns out to be the best light box I have ever had, with very even lighting by four 6000 K tubes. I would have never been able to make such a quality lightbox for so little money myself. I think in the medical business they are called "negatoscopes".

Excellent suggestion!!

Don

[David Ruby]

I just had an idea. In my dry area, the countertop has a location on my side (the wife has her own side of course) with a knee space below. I think this would be a great location to build in a light box from below. The glass would be flush with the surrounding counter. I'll have to add this to my to-do list!

[yeahyeah]

Keep it simple.

The xray viewer sounds like a great idea. Simple & inexpensive.

I still use the light box that my dad made for himself around 1940 when he was a teenager. 'Big Red' is VERY simply constructed and works perfectly well.

[Shesh]

There were 3 problems I encountered when I considered the x-ray viewers available via glass shops -
1. Could not find one 48" long.
2. The ones that used glass imparted a distinct dull muddy color and did not diffuse the light enough.
3. The ones which used acrylic used a very thin layer of acrylic (and hence could not support my bending over the box and viewing the film with the loupe.

I guess, if these problems can be avoided, x-ray viewers would be the way to go.