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VIVITEK QUMI LED 1280x800 - Page 70

post #2071 of 2165
Quote:
Originally Posted by Stoney Jackson View Post

I use a speaker mount. A cheap one I got at Home Depot or Walmart. The threaded part that screws into the Qumi then has another part that fits into the mount and is tightened with an Allen key.
Which I assume came with your speaker mount? I ask because I looked at a bunch of mounts online and saw no metal post that your screw into the mount so i figured I had to get the hardware for that part.
post #2072 of 2165
Quote:
Originally Posted by SubaruB4 View Post

Which I assume came with your speaker mount? I ask because I looked at a bunch of mounts online and saw no metal post that your screw into the mount so i figured I had to get the hardware for that part.
I should have taken a pic last night. There's a part that goes over the mounting hole with a "male" end and a screw that fastens the part to the speaker (or Qumi!) then the male end fits into the female end of the part that mounts to the wall or ceiling. Held together with Allen screw.
post #2073 of 2165
Quote:
Originally Posted by crashbot View Post

ALERT!!!

I have noticed slight cracks appearing around the camera thread mount in the base of my Qumi (I have it upside down, suspended from the thread mount). At first I thought these were simply the weight of the Qumi hanging from the thread insert, but now I realise they are because the mount is not in line with the centre of gravity of the Qumi, so there is a torque being applied continuously.

The torque can be relieved crudely by adding counterbalance weight, but this adds to the force being applied to the thread insert. My recommendation is to add a baseplate (eg plywood) the same size as the Qumi footprint, secured to the thread mount with a 0.25" Whitworth screw and a spacer, so that the existing rubber feet are in contact with the baseplate and remove the torque on the thread insert. The spacer on the screw is to prevent the screw being tightened beyond the stand-off created by the rubber feet (otherwise over-tightening could "extract" the thread insert).

A replacement camera thread mount can be provided by drilling and tapping a hole in the plywood baseplate in line with the centre of gravity (this will make it easier to suspend the Qumi without it wanting to twist the mounting). This is easily done by drilling the hole slightly undersize (eg a 5.5mm diameter instead of 6.5mm) and then screwing a 0.25" Whitworth bolt into it to cut the thread. However, with a plywood baseplate, many other mounting options become available (eg magnetic catches). The fastidious may want to let in a proper metal thread insert (eg glue a nut into a counterbored hole with epoxy resin).

OK folks, here's what I've made (design objectives: eliminate the stress on the Qumi mount; provide an alternative mounting point in line with the CoG SOS there is no tendency to twist; provide machinable surfaces for alternative mountings - eg quick-release dovetails or magnetic catches):



I'll talk you through it. There is a base plate and a top plate made from 8.5mm plywood, connected by four 50xM5 countersunk screws and four 36.5mm spacers made from 8mm aluminium tubing. These corner posts are threaded into the top plate by drilling the holes 4.5mm and then cutting the thread using the screws.

Photographs below show the parts and views of the assembly. Manufacturing details for the base and top plates are in the attached PDF. Note that the details given are for how it should be made, not exactly how my prototype turned out.

The base plate has a 6.5mm hole to take a 0.25" Imperial screw (Whitworth) and thread into the base of the Qumi Q2. The screw is shown with a washer to go under the head, and a tap (faucet) washer acts as a spacer to compensate for the Qumi's feet and also makes the screw captive. Without the spacer it would be possible to over-stress the base of the Qumi by tightening the screw too much. I had to thin the tap washer slightly, and of course the screw had to be trimmed to the appropriate length.

Also in the base plate is a 50mm hole for the fan air intake, and four rubber feet attached by woodscrews. The feet allow the assembly to stand on a surface without worrying about recessing the Whitworth screw head. The feet came from my local discount store as a pack of 6 "seat buffers" for under 1 GBP - if bought from the "traditional" DIY outlets they can be expensive. Delta tap washers could also be used.

In the centre of the base plate and the top plate are threaded holes for tripod screw mounting. These are simply holes drilled at 5.5mm and then the 0.25" Whitworth screw forced into them to cut the thread. The centre of gravity of the Qumi is very close to the centre line. Having both means the Qumi can be stood on or suspended from a camera mount either way up (which I need as my bedroom requires the Qumi projects from a low position but suspended, and my lounge is suspended from a high position).

The main purpose of the top plate is to take the stress off the Qumi's thread mount when suspended, by supporting it from underneath. Any slight gap between the fitted Qumi and the top plate can be filled with packing, eg paper or card. If you don't care about this, and only plan to mount the Qumi from the base anyway, the top plate and corner posts can be dispensed with, and the dimensions of the base plate can be reduced to 160x102mm (no corner holes required). If you require access to the Qumi's control pad, a suitable aperture will need to be cut in the top plate (but I always use the remote).







QumiMount.pdf 27k .pdf file
Edited by crashbot - 8/22/13 at 2:43am
post #2074 of 2165
Quote:
Originally Posted by Stoney Jackson View Post

I should have taken a pic last night. There's a part that goes over the mounting hole with a "male" end and a screw that fastens the part to the speaker (or Qumi!) then the male end fits into the female end of the part that mounts to the wall or ceiling. Held together with Allen screw.
If you can get a picture that would be great!
post #2075 of 2165
Quote:
Originally Posted by SubaruB4 View Post

If you can get a picture that would be great!




Wow, I had to dust after I saw that picture!
post #2076 of 2165
Quote:
Originally Posted by Stoney Jackson View Post





Wow, I had to dust after I saw that picture!
I'm going to have to see if they have that mount in home depot on the website I don't see it

Oh wait I found it on Amazon!
Edited by SubaruB4 - 8/21/13 at 8:18pm
post #2077 of 2165
Quote:
Originally Posted by SubaruB4 View Post


Oh wait I found it on Amazon!
Have you got a link?
post #2078 of 2165
This is my top mount (until I replace it with quick-release) - it's a camera adapter, and is screwed into the ceiling (actually an overhead cupboard) on yet another Whitworth thread. The locking ball joint allows for adjustment. The screw at the bottom is on a quick-release plate, but it is not very convenient.

post #2079 of 2165
Quote:
Originally Posted by mihaid View Post

Have you got a link?

http://www.amazon.com/Universal-Satellite-Speaker-Brackets-Ceilings/dp/B000XWMVT8/ref=wl_it_dp_o_pC_nS_nC?ie=UTF8&colid=2SL806KMBHAVY&coliid=I2FKNW0324IPOD

It's in white too which looks a bit better IMHO.
post #2080 of 2165
Are these the same? You only have to buy two (presuming you only need one!):

http://www.amazon.com/VideoSecu-Satellite-Brackets-Ceilings-MS20W2/dp/B002WN8NHA/ref=pd_sim_e_5
post #2081 of 2165
Quote:
Originally Posted by crashbot View Post

ALERT!!!

I have noticed slight cracks appearing around the camera thread mount in the base of my Qumi (I have it upside down, suspended from the thread mount).

I was thinking of bastardizing a tripod I have by just removing the legs and screwing the rest in a ceiling beam. similar to this photo(mine does not have the rack thing), the handle thing is useful in rotating to a different wall.

Was yours moved frequently by manhandling the projector or suspended in situ and left there until cracks appeared.
post #2082 of 2165
It wasn't moved much, but I admit that is a possibility. Having a tripod head with a handle is definitely an advantage.
post #2083 of 2165
Quote:
Originally Posted by crashbot View Post

Are these the same? You only have to buy two (presuming you only need one!):

http://www.amazon.com/VideoSecu-Satellite-Brackets-Ceilings-MS20W2/dp/B002WN8NHA/ref=pd_sim_e_5
Yeah this works too I was just looking really quick
post #2084 of 2165
Qumi Q2 PSU Replacement

In my pursuit of being able to move the Qumi between two situations quickly and easily, I wanted to provide a replacement PSU for the second location. The Qumi PSU has a "19V 3.42A" rating and centre pin positive on the label (if you look at it under a microscope!).

Through eBay I found an Acer Aspire replacement PSU "buy now" for a whole £5.30 (GBP) delivered, but then discovered that although I had estimated the outside diameter correctly, the centre pin was too small. I replaced the DC connector with a 5.5/2.5mm x 14mm plug from Maplin (HH63T) for £1.99 and it works - my Qumi Q2 is running from it as I write. The original plug is 11mm long, but the next size down available from Maplin is 8mm.

As far as I can see, a replacement PSU for various Toshiba, Acer, HP, Dell, & Fujitsu notebooks would have the correct connector, and are rated 19V 4.74A.

* I think it is only right to point out that these cheap PSUs (even though from a "UK supplier") are of foreign origin, and although carry the appropriate standards markings (in our case "CE") there is no certainty (and indeed considerable doubt) that they are actually audited to conform to the safety standards requirements. One therefore uses them "at one's own risk", and should be sensible with appropriate consideration and care. I would not, for example, leave one powered up unattended until I had a substantial history of it not overheating, and an isolation test between mains input and DC output is advisable.
Edited by crashbot - 9/7/13 at 4:07am
post #2085 of 2165
My LED hours counter appears to have gone "around the clock". It is currently reading 489 eco and 74 standard, and I am positive the eco figure should be a lot higher than that (this is my bedroom TV, usually on for several hours a day and frequently all night, and this has been the norm for over two years).
post #2086 of 2165
I have caved in and bought a Q5. My bedroom Q2 will now remain where it is with the Q5 providing the home cinema function (and any portable requirements). First impressions:
  • Full size HDMI socket much more convenient, although I have furnished myself with adapters.
  • No physical on/off switch, only a standby button on the unit and the remote. This does not appear to stop the hours count when in standby. The only way to stop the hours count seems to be to unpower it. This is bad.
  • Even side-by-side from the same HDMI feed, the Q5 is only a little brighter than the Q2. I could not find a setting where the colours match.
  • Sound still pointless except in the most intimate of situations (and then drowned out by the fan). Why waste the space on a speaker? Anyone needing sound in a mobile situation could use some powered PC speakers plugged into the audio output socket.
  • My unit has no obvious problems with focus, perhaps this has been fixed in production (my Q2 didn't either - lucky I guess).
post #2087 of 2165
What is the resolution on Q5?
post #2088 of 2165
Same as the Q2!
post #2089 of 2165
What is, if any, fan noise difference in full normal mode between Q2 and Q5 say after they've been running in that mode for 5 min.
post #2090 of 2165
I've not measured it, but it seems about the same and no reason to suspect it is any different.
post #2091 of 2165
Quote:
Originally Posted by crashbot View Post

ALERT!!!

I have noticed slight cracks appearing around the camera thread mount in the base of my Qumi (I have it upside down, suspended from the thread mount). At first I thought these were simply the weight of the Qumi hanging from the thread insert, but now I realise they are because the mount is not in line with the centre of gravity of the Qumi, so there is a torque being applied continuously.

The torque can be relieved crudely by adding counterbalance weight, but this adds to the force being applied to the thread insert. My recommendation is to add a baseplate (eg plywood) the same size as the Qumi footprint, secured to the thread mount with a 0.25" Whitworth screw and a spacer, so that the existing rubber feet are in contact with the baseplate and remove the torque on the thread insert. The spacer on the screw is to prevent the screw being tightened beyond the stand-off created by the rubber feet (otherwise over-tightening could "extract" the thread insert).

A replacement camera thread mount can be provided by drilling and tapping a hole in the plywood baseplate in line with the centre of gravity (this will make it easier to suspend the Qumi without it wanting to twist the mounting). This is easily done by drilling the hole slightly undersize (eg a 5.5mm diameter instead of 6.5mm) and then screwing a 0.25" Whitworth bolt into it to cut the thread. However, with a plywood baseplate, many other mounting options become available (eg magnetic catches). The fastidious may want to let in a proper metal thread insert (eg glue a nut into a counterbored hole with epoxy resin).

 

Has anyone else had this problem?  I'm wondering how long crashbot had this mounted before cracks started to appear.  If I have it up for a year - is that far too long?  I have a ceiling mount (1/4-20 upside down tripod), but I'm concerned that this might damage the Qumi.

post #2092 of 2165
Bear in mind that the cracks might have been caused by stressing it while adjusting the angle. I do not think they are very serious, but the idea of moving the mounting point to the centre of gravity is an appealing one (speaking as an engineer). If yours is showing no signs of cracks, don't worry about it (unless you are a perfectionist).

I have not settled what I will do to mount the new Q5 yet.
post #2093 of 2165
Quote:
Originally Posted by crashbot View Post

I have caved in and bought a Q5. My bedroom Q2 will now remain where it is with the Q5 providing the home cinema function (and any portable requirements). First impressions:
  • Full size HDMI socket much more convenient, although I have furnished myself with adapters.
  • No physical on/off switch, only a standby button on the unit and the remote. This does not appear to stop the hours count when in standby. The only way to stop the hours count seems to be to unpower it. This is bad.
  • Even side-by-side from the same HDMI feed, the Q5 is only a little brighter than the Q2. I could not find a setting where the colours match.
  • Sound still pointless except in the most intimate of situations (and then drowned out by the fan). Why waste the space on a speaker? Anyone needing sound in a mobile situation could use some powered PC speakers plugged into the audio output socket.
  • My unit has no obvious problems with focus, perhaps this has been fixed in production (my Q2 didn't either - lucky I guess).

Can you possibly take a photo side by side on the q2 and q5 for comparison, I think you are the only dude in the world that have both, or make a video much better. Because a local store here in San Francisco sells the Qumi Q2 for $250 taxed and the Q5 $387 taxed. That would help me much on what to buy.
post #2094 of 2165
I will do when I get a chance. I presume you mean the projected image; there's no point in posting pictures of the Qumis themselves because you can get those from Vivitek.
post #2095 of 2165
Quote:
Originally Posted by crashbot View Post

I have caved in and bought a Q5. My bedroom Q2 will now remain where it is with the Q5 providing the home cinema function (and any portable requirements). First impressions:

  • Even side-by-side from the same HDMI feed, the Q5 is only a little brighter than the Q2. I could not find a setting where the colours match.

500 lumens vs 300 is not a world of difference. In deciBels we are looking at less than 6dB difference. I know signal amplitudes better than luminance... It is an improvement I might like when watching 3D on the Q2 - it's a little too dark for good 3D over say 48". I still push it to 60" though and enjoy the effects and the movies. My Q2 puts out a decently bright 2D image at 60" in a dimly lit room. As an upgrade I'm looking at the Benq W1070, or minimum Benq 770st. Not LED projectors but what the heck, I want bright HD3D on a 72" screen.
post #2096 of 2165
I agree, the brightness improvement doesn't merit a 55% price difference - I only wish we could get them for those prices in the UK!
post #2097 of 2165
I too wish it were possible to find those prices here in Brazil, but it's already nearly impossible to find the projectors!
post #2098 of 2165
Here is a still frame from the BluRay edition of Skyfall, simultaneously displayed (via split HDMI) by a Q2 (many hundreds of hours eco on the clock) and a Q5 (new), both in full brightness mode and as best as I could with the same profile settings. Q5 at the top.

LEAD Technologies Inc. V1.01
post #2099 of 2165
Quote:
Originally Posted by crashbot View Post

Here is a still frame from the BluRay edition of Skyfall, simultaneously displayed (via split HDMI) by a Q2 (many hundreds of hours eco on the clock) and a Q5 (new), both in full brightness mode and as best as I could with the same profile settings. Q5 at the top.

Definitely a significant improvement in brighteness for the Qumi5 in your image . Thanks for posting the comparison. My Qumi2 at 60" seems as bright as the Qumi5 in your image, but with 3D glasses almost looks as dark as your Qumi2 image. But I do not keep my room very dark.

Cheers -
post #2100 of 2165
I don't know if this will prolong my Qumi Q2 but I did a diy cooler for it, now the top never gets warm at all, it is still cold to touch after I played BF4 for 4hrs+ and I can feel the vent beside the bulb is really sucking air, it even suck the white letter paper if I place one beside it. Please don't laugh I only made this with a USPS box duck tape from $1 store and an old fan from my old desktop and use a 12volts ac adaptor from my old wifi router thanks to comcast they gave us a modem with router on it. I did this on my old xbox 360 with the prone red ring of death defects and mine never experience the rrod so I decided to do it here on my Qumi thinking I am not gonna loose anything anyway. I only got the Qumi for $250 and some change so I need to do some safety precaution. As far as fan noise, I don't hear any of that I have 5.1 bose surround sound so even at minimum volume I don't really hear it.













Edited by KikiM - 11/8/13 at 11:58am
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