Hey kiddies-
I've been reading on here and plan on building my own projector whenever I get some bankroll but I have a question/suggestion -- From what I gather, it seems like these projectors would produce a fair amount of noise. Those of you that have made one - is that the case? Is it bothersome? I know the OHP's we used in class in High school were very loud and I couldn't imagine having that noise in the room when I'm trying to watch a flick. My xbox was kind of loud so I took the case apart and put dynamat inside the case and that brought the volume down a few dB to a more acceptable humm. Has anyone attempted this with a projector or would it work? Would there be problems with the heat from a bulb and the tar? Am I completely off my rocker?
~Jason
I've been reading on here and plan on building my own projector whenever I get some bankroll but I have a question/suggestion -- From what I gather, it seems like these projectors would produce a fair amount of noise. Those of you that have made one - is that the case? Is it bothersome? I know the OHP's we used in class in High school were very loud and I couldn't imagine having that noise in the room when I'm trying to watch a flick. My xbox was kind of loud so I took the case apart and put dynamat inside the case and that brought the volume down a few dB to a more acceptable humm. Has anyone attempted this with a projector or would it work? Would there be problems with the heat from a bulb and the tar? Am I completely off my rocker?
~Jason
Sounds like an idea that would work mate...although the noise don't bother me greatly to start with it aint that loud to be honest...
From a recent [H]ardforum thread :
Use thick, dense foam, ideally in the peaks/valleys shape.
Try to find something that doesn't burn easily(I see this being a major hazard if you line the area near the bulb)
Also, make fan shrouds - 3" elevated pieces of wood w/ foam on them that are 2-3" wider than the fan itself. These are supposedly quite effective.
Before you do any of this, though, see how loud your PJ is - using two or three 120mm quiet case fans running on half the normal voltage should be virtually silent in the first place.
Also, Dynamat smells.
Use thick, dense foam, ideally in the peaks/valleys shape.
Try to find something that doesn't burn easily(I see this being a major hazard if you line the area near the bulb)
Also, make fan shrouds - 3" elevated pieces of wood w/ foam on them that are 2-3" wider than the fan itself. These are supposedly quite effective.
Before you do any of this, though, see how loud your PJ is - using two or three 120mm quiet case fans running on half the normal voltage should be virtually silent in the first place.
Too true i use 2x120mm in mine plus a 100cfm blower fan and shes whisper quiet all fans on approx 1/2 speed. Big blade fans at slower speed move lotsa air and dont make a racket..
awesome. thanks for the feedback. I hadn't considered the heating plus the smell of the dynamat effect. that could have disasterous implications
! Do you guys splurge on the nice "phantom quiet" 120mm fans or just use regular cheapo run of the mill 120mm case fans?
~J
! Do you guys splurge on the nice "phantom quiet" 120mm fans or just use regular cheapo run of the mill 120mm case fans?~J
I use Sunon & Evercool myself coz they are readily available and reasonably cheap but you could use anything that takes your fancy bud the depth of your pockets, the length of your arms and how much cash is in them pockets is really the only limitation 🙂
Get cheap sleeve bearing if you're willing to replace them every 6-12 months, cheap ball bearing if you're willing to tolerate slightly more noise.
Sleeve bearings have a much lower life expectancy, and ramp up in noise as they die(The deathknell, while it MAY last you at least a year more, is horrendously loud/uneven), whereas ball bearings start out louder, and stay there.
Sleeve bearings have a much lower life expectancy, and ramp up in noise as they die(The deathknell, while it MAY last you at least a year more, is horrendously loud/uneven), whereas ball bearings start out louder, and stay there.
You know you can oil and grease fans...........
A typical well looked after sleave bearing fan will last upto 4 years silently, but you have to oil or grease them every 6 months, (grease longer). Ball bearing fans are silent when greased.
Trev🙂
For quiet fans, sewing machine oil is your friend. In a pinch 5w30 motor oil will do, but it will reduce the fan RPM for a while, until it thins.
Keep a nice smooth air flow path, and that will help keep the noise down, too.
Keep a nice smooth air flow path, and that will help keep the noise down, too.
fan mounting
I mounted a 120 VAC 65 CFM fan directly on my plywood PJ box, and it made a sounding board. Just like the difference between strumming an electric guitar with the power off versus strumming an acoustic guitar. It was so loud you could hear it from the other side of the house!
So then I mounted my fan on a piece of aluminum plate cut to give me a 1" lip all around. I wrapped that aluminum in 3/8" high density foam and cut some aluminum angle extrusion to clamp that against the wall of the box. Much much quieter! (The foam is from a $1 piece of pipe insulation from the home improvement store.)
So if your fan runs much quieter in your hand than it does mounted in your box, you can gain a lot by working on the mounting.
I mounted a 120 VAC 65 CFM fan directly on my plywood PJ box, and it made a sounding board. Just like the difference between strumming an electric guitar with the power off versus strumming an acoustic guitar. It was so loud you could hear it from the other side of the house!
So then I mounted my fan on a piece of aluminum plate cut to give me a 1" lip all around. I wrapped that aluminum in 3/8" high density foam and cut some aluminum angle extrusion to clamp that against the wall of the box. Much much quieter! (The foam is from a $1 piece of pipe insulation from the home improvement store.)
So if your fan runs much quieter in your hand than it does mounted in your box, you can gain a lot by working on the mounting.
Nice work Guy...I usually cut four squares approx 10mmx10mm out of rubber (old neoprene mouse pads work well) and epoxy them next to the fan mount holes before mounting the fan....stops all the virbration for me 🙂
fan mounting
I was think about doing something like that, but I thought the mounting bolts would conduct the sound just as well as solid mounting. So I came up with a design with nothing but foam between the aluminum plate the fan is mounted on, and the wall of the box. A cross bar at the top and bottom each hold another piece of foam against that aluminum plate to clamp it to the wall of the box. So nothing that vibrates is connected to the box.
Normally, this is all inside an air duct. I removed the front piece to take the photo.
I was think about doing something like that, but I thought the mounting bolts would conduct the sound just as well as solid mounting. So I came up with a design with nothing but foam between the aluminum plate the fan is mounted on, and the wall of the box. A cross bar at the top and bottom each hold another piece of foam against that aluminum plate to clamp it to the wall of the box. So nothing that vibrates is connected to the box.
Normally, this is all inside an air duct. I removed the front piece to take the photo.
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