DIY Gobo Build.

[Vic]

Hi All,

And ahappy new year to everyone.

I am thinking about building some gobo's, maybe 4 in total.

I intend building one reflective and one absorbative side ( I even have come binary diffusers left over I might stick on one side).

Anyway, as I don't have a great deal of experience in using different types of gobos, I had two questions that I wondered if people might provide their advice on.

1) I was wanting to make them short, say 4ft high, so that people can see over them while playing (if standing). Does anyone have any opinions about that in terms the effectiveness if I build them taller (say 6ft). (i do have 4 sheets of glass I could use 2 on each if I were to build some taller ones.

2) My next questions is about wheels? If I sit them up on wheels is that doing a big disservice? If I were to make the shorter gobos as mentioned above, would it be best to put no wheels but maybe add a Lifting/handle hole on each side so they are easy to lift into place?

Any thought out there?

Vic

[The Tasmanian]

Hi Vic, I built quite a few of these, and then had decades to review them in sessions.
I built 6 x 1.2m high - and 3x2m high
- some were reflect 1 side & absorb the other.
- some were absorb both sides.

The double sided absorb ones ended up being used 98% of the time - I found its not often one wants another reflection from a gobo when the floor is wood.
In a carpeted booth, the reflective gobo's had more chance of being used.
Wheels were a must - as cables could be easily run underneath, and 1 person can adjust position & angles mid session.
I also used 50mm tontine and a soft cloth covering so the gobo's really absorbed. This was great for guitar amps and drums.

I have also built some see through panels, Glass seems like a good idea - but in reality, most of the time it adds problematic reflections, its very top heavy and quite dangerous if it falls over
I've found perspex lighter/safer and less harsh sounding.

Best of luck with the studio in 2015!

[Ausrock]

I have five that I built around ten or more years ago..........roughly 1200 X 900. The frames are made from approx., 100 X 20 Radiata, one side is MDF sheet (reflective) and I used 50mm rigid acoustic insulation f/glass sheet on the other side for absorb with a 50mm void between the f/glass and the MDF, the whole thing is covered with coloured hessian purchased from Spotlight. They're on wheels and have been worth their weight.

[Vic]

Thanks both,

That's really great info.

RE the wheels, did you both use standard castors? What was the rough height off the ground? Did the castors sit underneath or did they splay out to the side allowing the gobo to come down closer to the floor.

I would love if I could just use a castor underneath, for ease, but just wanting to make sure it's not going to reduce the effectiveness of the gobo.

Thanks

Vic

[Ausrock]

Vic,

I screwed two pieces of 12mm ply approx., 250 x 50mm to the bottom and attached el cheapo castors to the ply........the castors are spaced far enough apart that the gobos won't tip over.

Over time the ply has been weakening and I'm planning on doing a rebuild of the wheel set up........just haven't figured the best option yet.

Cheers.

[Kurt]

Use those steel right angled brackets sold for hanging shelves. Maximum toe and ankle carnage...

Over time the ply has been weakening and I'm planning on doing a rebuild of the wheel set up........just haven't figured the best option yet.

Cheers.

[Ausrock]

Use those steel right angled brackets sold for hanging shelves. Maximum toe and ankle carnage...

Over time the ply has been weakening and I'm planning on doing a rebuild of the wheel set up........just haven't figured the best option yet.

Cheers.

[The Tasmanian]

Vic, I would avoid normal casters - and use the 2 inch heavy duty wheels with a rubber outside of the wheel.
Normal casters get clogged up with rubbish, & drag on leads - and squash them.
They also wont last, the plastic will break, scratch the floor etc.
There is a way to build gobo's using 2-3 inch wheel, and only have a small gap underneath the panel itself for leads.

Other dodgy ones I collected and used in the past eventually collapsed at the base - hence I built heavy duty ones which were built to last - and they have.
I'll try to draw a ruff diagram and post.

[The Tasmanian]

This ruff diagram:
End view, + section view (or if gobo was cut vertically)
Leaves roughly 15mm underneath for cables - and solid bracing.
The legs need to be roughly 800mm long for smaller 1.2m high gobo's - probably 1m long legs for tall gobo's.
(Edit - this is total leg length IE: 800mm leg has 400mm hanging out each side)
Lucky I'm originally a chippie by trade (obviously not a graphic designer).
PM me if you are unsure of any of this
Cheers
CT

[seb]

thanks for the brainstorming on this one
I have been trying to work out how to do some wheels on mine.
kurt for the angles, chris for the bracing.
cheers
seb

[Senad]

http://johnlsayers.com/phpBB2/viewtopic ... light=gobo

...not sure how clear the picture is (not very on my phone) but you could also check the link out

[Vic]

Thanks everyone,

Sorry for not responding for a while, but I've been away.

The diagrams look great, I'll come back with any questions once I get the job underway

Ta

Vic

[Drumstruck]

Hey Vic,

I got some gobos from a famous colleague (o you name dropper...) that work really well.

Laminated glass in the top insulates better and doesn't rattle / batts in the bottom / one hardwood reflective side and one perforated masonite absorbtive side.

I have stained the timber to make them pretty and added acoustic foam on the absorbtive side) and draping rugs over the top if the glass is too reflective works fine. Casters as per Chris' drawing. A little skirting strip of wood along the bottom stops most of the leakage there. These ones are more than 2m high so they can sit flat against a door or window for extra insulation etc.

https://dl.dropboxusercontent.com/u/991 ... 0front.jpg
https://dl.dropboxusercontent.com/u/991 ... 20rear.jpg
https://dl.dropboxusercontent.com/u/991 ... 20side.jpg