Should I use TECs in my mini RGB projector?

[kitatit]

Hi guys,

I'm a bit unsure wether I should use TECs in my mini RGB projector.

I want to build a quality projector that I'm proud of but don't want to over complicate it if there is limited benefit for a projector this small.

Dave has been helping me out a lot, but due to my lack of experience, it's almost a full time job for Dave answering all my questions,Thanks Dave so I thought I'd ask for your ideas and opinions.

The 3 most important attributes are;

1- Very compact
2- Good graphics ability
3- As quiet as possible

The components I've bought for this projector so far is;

-DT40 Pro scanners
-Swislas dicros
-1xCNI OEM 12mm diameter 532nm 100mw Green laser.
-1xNichia NDB7352E 445nm 50-150mw blue laser.
-3x Die4Drive Pro drivers
-Die4Chill TEC drivers


Yet to buy;

-1xOpnext HL6385-E 642nm 150mw red laser.
-TEC or TECs.

Soooo..... do you think it is worth using TEC cooling in this projector?

TEC = better stability and longer life right?

If I didn't bother to use one or more TECs, how would the power instability manifest in a baby RGB like this?

Would it appear as colour fluctuations?

What are the pros and cons when deciding to TEC or not TEC?

Any advice guys?

Thanks
Kit

[badger1666]

tecs are a good idea but you will have to build everything on a big heat sink
to get rid of all that tec heat
myself i would not bother for the kind of powers your using
just put a couple of fans to vent the case and put your lasers on 8mm ali
go to my profile and look at pics of my builds i dont use tecs and have run my stuff two day solid with out even getting warm , i just build my projectors on a giant heat sink
in the first place

[kitatit]

Hi Badger,
thanks for the clues

Yes I'm looking at a heat sink like this-
http://cgi.ebay.com.au/Large-Aluminu...#ht_500wt_1154

After I've done a CAD assembly, I might use a smaller heat sink when I figure out how small I can make it.

My plan is to use this as my base plate and have the fins facing inwards while the flat side forms the outer casing to save space. I'll machine away just enough of the fins to fit in the components.

[danielbriggs]

I wouldn't bother with TEC's at those powers.

Tip: Ensure you get a suitable grade of aluminium.
Some alloys are like chewing gum and are a nightmare!

[badger1666]

that heatsink looks just the ticket for an rgb build
do you have rs components over there ? that where i got mine
find yourself an electronics wholesaler on the web local to you might find a deal
and save shipping and import costs

Hi Badger,
thanks for the clues

Yes I'm looking at a heat sink like this-
http://cgi.ebay.com.au/Large-Aluminu...#ht_500wt_1154

After I've done a CAD assembly, I might use a smaller heat sink when I figure out how small I can make it.

My plan is to use this as my base plate and have the fins facing inwards while the flat side forms the outer casing to save space. I'll machine away just enough of the fins to fit in the components.

[kitatit]

Hi Dan,

Ah, thanks for the ali tip.

Yes I once had a dud billet of aluminium.

We had to take it back.

It machined like crap.

Nice one, I'll be sure to ask about about it's properties.

Thanks mate.
Kit

[dave]

I question whether you will need much of a heatsink at all TBH. The red and blue lasers will generate a minimal amount of heat. The green will need more heatsinking, however if the case is used to dissipate the heat, you should be fine. Another thing is the green module is far from temperature sensitive.

The one thing that will be important is adequate air flow around the switchmode supplies. Even if its just well designed convection, so there is a big vent directly above the supplies and another vent beside or below the supplies..

[kitatit]

that heatsink looks just the ticket for an rgb build
do you have rs components over there ? that where i got mine
find yourself an electronics wholesaler on the web local to you might find a deal
and save shipping and import costs

Yes we do. I buy a range of stuff from them. Mostley as a last resort. They have a great catalouge but they are often very expensive. We still get ripped off for some things in Oz. Often it's cheaper to buy things from overseas and pay shipping due to much cheaper prices and you don't pay GST(VAT) or import duties on items under $1000AUD.

I question whether you will need much of a heatsink at all TBH. The red and blue lasers will generate a minimal amount of heat. The green will need more heatsinking, however if the case is used to dissipate the heat, you should be fine. Another thing is the green module is far from temperature sensitive.

The one thing that will be important is adequate air flow around the switchmode supplies. Even if its just well designed convection, so there is a big vent directly above the supplies and another vent beside or below the supplies..

Thanks Dave that's good advice, I'll incorporate that I. My design.

Well, it's settled, no TECs in this build.

Sweet, the list of variable is getting shorter.

Thanks alot guys, much respect

Kit

[dnar]

The thing you need to understand about TEC's is this.

The "hot" side must dissipate the sum of the heat moved across the TEC and the energy put in to the TEC!

ie if it takes 10W of input power to pump 5W of heat from the cool side, then the hot side must dissipate 10 + 5W = 15W of output heat....

Without a sufficient heatsink on the hot side, you go backwards and end up heating what should be to cold side of the TEC...

Food for thought...

Sometimes a simple heatsink and fan is all that is required.

My 2 cents.