nestor
Well-Known Member
another idea that might work better is get some screws long enough to go through the pvc and through the fan into the heatsink. Then just mount them to the pvc frame.
4x2.5 cab outfitted with a diy cxa3070 build
- Thread starter Al Yamoni
- Start date
AquariusPanta
Well-Known Member
nestor
Well-Known Member
Clean off the grease before you drill and tap. Trying to reuse whats already there isn't going to give you the results you want and getting metal shavings mixed in will give you an uneven contact. Its not the best place to skimp on resources. You only need a drop for each chip.
Positivity
Well-Known Member
In case you ever want to use reflectors or the reflector adapter you may want to spin the holder so all 4 screw mounts are able to be tapped. Might just make it how it is though..
If you don't anticipate reflectors then how it is looks good..centered..
Tapping is easy but i'd practice on a spare piece of metal first to get the confidence up and get a feel for it
Al Yamoni
Well-Known Member
It probably wouldn't have broken if I had done this.. haha.
Al Yamoni
Well-Known Member
Yikes!110. Removal of Broken Tap.-
Taps will sometimes break off, even when used with care.
There are two ways of satisfactorily removing the broken part of a tap from a hole:
(1) by means of a tap extractor;
(2) by using a chisel or punch.
A tap extractor having 4 "fingers" that slip along the flutes of the tap is shown in Fig. 92.
This tool is turned with a wrench, which must be used carefully to prevent damage to the long thin fingers of the extractor.
FIG. 92. USE OF TAP EXTRACTOR.
Broken taps can often be removed by using a blunt cold chisel or a taper punch, as shown in Fig. 93.
103
FIG. 93. REMOVING BROKEN TAP WITH PUNCH.
If done carefully, this will frequently start the tap.
The job can then be completed with a tap extractor as previously described.
Taps often shatter when they break; the broken pieces should be picked from the hole with a small prick punch or a magnetized scriber before any attempt is made to remove the tap.
Removing a broken tap by any method is often a long, tedious job which requires time, skill, and patience.
It is therefore wise to avoid breakage by being as careful as possible.
http://www.maritime.org/doc/tools/part2.htm
http://www.waltontools.com/products/remvtap.htm
http://www.newmantools.com/walton/extrtap.htm
saludos
Abiqua
Well-Known Member
I really enjoy your pvc setup, I have all this laying around too, elbows tees and 1/2 inch pipe....so eazy!
One thought about the corners has me worried. Each inner corner that points towards your middle cob is unsupported, how about carrying over with more tees to at least support the corners from drooping at the worst moment....or maybe you had something in mind...
PS Great Job on the Sinks!
Did you do them by hand or did you have some tools? Looks great!
Al Yamoni
Well-Known Member
Excellent question! I plan on using PVC cement, and that stuff is super strong. I use it all of the time out in the garden. Gluing them will take place just before I wire them.I really enjoy your pvc setup, I have all this laying around too, elbows tees and 1/2 inch pipe....so eazy!
One thought about the corners has me worried. Each inner corner that points towards your middle cob is unsupported, how about carrying over with more tees to at least support the corners from drooping at the worst moment....or maybe you had something in mind...
PS Great Job on the Sinks!
Did you do them by hand or did you have some tools? Looks great!
Thank you! I just used a drill with the corresponding bit(that was easy as pie) and I tapped them with a hand tool(difficult part). Took several hours because I had no idea what I was doing..
I went with the previous advice of using extreme caution and loads of patience, twisting in some, then all the way out and cleaning the aluminum bits out. Re apply oil and go a lil deeper than the last twist until it was all the way through.
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Al Yamoni
Well-Known Member
Do I need to spread the drop of thermal paste over the entire backing of the chip or just a drop in the center and smooth it slightly..?
Abiqua
Well-Known Member
Al, what I like to do is drop in the center and then push the diode down and gently work pressure around to all 4 corners and a little circular motion at the end to fill in the gaps. This way I can get as thin of a line as possible of thermal paste. I try and get it so thin, that none oozes out...
My 1st tries didn't always cover the entire bottom of the diode, but were very close and heating never seemed to be too much of an issue.....after a few tries, it became clockwork....but I still think silicon pads are the future! The paste can be so inconsistent when applied in this manner......
Some brands come with a little spreader with the paste tubes, you could use a clean credit card too....
After some reading last night on thermal conductivity and thermal impedance, my feelings are that we should try to get as thin of a paste line as possible when using higher impedance paste and you can get away with less with a lower impedance paste.
Since impedance seems to be directly related to actual thickness [in this case thermal paste] of the substrate....and rises the thicker it becomes, while thermal conductance on the other hand can remain the same whether a material is 1mm or 10mm thick.....less seems to be more.....
nestor
Well-Known Member
I don't know if you have any experience building computers, but its the same principle - a drop in the center. It will spread out when you place the chip down and it will work itself into any gaps as it warms up.
If you feel more comfortable spreading it around, you can do that. The only thing that really matters is that there's enough to transfer the heat. The problem with this approach is that you can use too much.
Abiqua
Well-Known Member
Building a cpu is certainly a great experience for this kind of stuff and I do have that kind of experience as well. imho, the chips don't seem to get nearly as hot as CPU's and have different thermal characteristics as well...some of this was brought up when re-mounting diodes. I too have seen this effect, even weeks after assembly and then breakdown, the paste just doesn't seem to spread as well, unless it is manually done.
my feeling is a that a higher thermal impedance layer may be more beneficial than a equally thick layer of lower impedance substrate.
but, I think this again just leads to more argument for silicone pads which can take out some of the inconsistency of manually apply paste
