I'm sure
One last thing. If you are only shallow drilling, you may like to clear out the tapping hole with a flat bottom drill to get maximum thread length.
All the best.
These flat bottom drills are more like a router bit?
Can you use them handheld?
I can see you are from GB. From my father I have some vintage Eclipse tools. E.g. like these:
Eclipse from Sheffield.
Think everything will succeed with Eclipse!
This type of tap wrench often gives a bit more control (e.g to get the 1st tap (taper) to "bite").
I think the tool brand Eclipse still exists.
The tools above could be 50 years old.
Can you use them handheld?
I can see you are from GB. From my father I have some vintage Eclipse tools. E.g. like these:
Eclipse from Sheffield.
Think everything will succeed with Eclipse!
This type of tap wrench often gives a bit more control (e.g to get the 1st tap (taper) to "bite").
I think the tool brand Eclipse still exists.
The tools above could be 50 years old.
Yes, those small tap wrenches allow for good 'feel'. The automatic centre punches are nice. Re the flat bottom drill, the hole is mostly made so it's just clearing out the point angle from the drill to get half or one more pitch of thread in the hole. Your father and you clearly know good engineering. We just grind it carefully by hand on a pedestal grinder. It will self center in the existing hole.
PS.
Yes, it's a bit like that, or like an end mill/slot drill. HSS will be fine. SKF I would imagine make some. Remember, for Ali anything will do.
This is just to show the approximate look.
https://www.ebay.co.uk/itm/354299337582?hash=item527de2db6e:g:zhcAAOSwRzFjMX4T&var=623693207873
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These "end mills" are very nice. I must remember that I should not drill 4mm hole for M4 but something like 3.3mm and maybe not easy to find a 3.3mm "end mill"? ......probably everything is possible if I find the right tool-store. Not much effort in aluminium to make the hole flat at the bottom.
Probably "real pro's" don't use automatic centre punches 🙂 ......but I like them. I also have a Starrett which also makes nice tools.
Probably "real pro's" don't use automatic centre punches 🙂 ......but I like them. I also have a Starrett which also makes nice tools.
Found a 3.2mm "end mill"
https://dk.rs-online.com/web/p/endefraesere/7287831
Just a bit expensive at 60 USD or so. A cobolt-steel powder-metallic type. Just hard enough for aluminium.
https://dk.rs-online.com/web/p/endefraesere/7287831
Just a bit expensive at 60 USD or so. A cobolt-steel powder-metallic type. Just hard enough for aluminium.
Hi.
RS is always expensive. You could buy a 1/8 inch End Mill which is 3.175 MM they are common.
https://www.ebay.co.uk/itm/39326222...XovI6IhAK4nVSgItAAMyAFR4UX|tkp:Bk9SR663gbCOYQ
Any engineering tools supplier will have them I would think.
https://www.zoro.co.uk/shop/cutting...ziz15YDOi-QlZkJ0BEnaQXS_t3qP5NqEaArTPEALw_wcB
So probably less than 5 Euro.
RS is always expensive. You could buy a 1/8 inch End Mill which is 3.175 MM they are common.
https://www.ebay.co.uk/itm/39326222...XovI6IhAK4nVSgItAAMyAFR4UX|tkp:Bk9SR663gbCOYQ
Any engineering tools supplier will have them I would think.
https://www.zoro.co.uk/shop/cutting...ziz15YDOi-QlZkJ0BEnaQXS_t3qP5NqEaArTPEALw_wcB
So probably less than 5 Euro.
I have worked on my alu panels, and they are now fine and even. I have also cut a transparent acetat foil to mark the holes on so it can be used as a template to transfer markings for the holes on heatsinks and panels.
I have placed some nuts by eye to show where holes could be placed to secure the panels to the heatsinks.
I prefer the outer placement of the holes so it will not interfere with PCB and components. It will also look better. But the inner placement will probably be more technical correct to ensure best contact between panels and heatsinks. I will use heat paste so it should be ok with outer placement.
The heat paste I have is so old that it has split into "two phases".
Is there a recommended heat paste to use or just the usual "white stuff"?
I have placed some nuts by eye to show where holes could be placed to secure the panels to the heatsinks.
I prefer the outer placement of the holes so it will not interfere with PCB and components. It will also look better. But the inner placement will probably be more technical correct to ensure best contact between panels and heatsinks. I will use heat paste so it should be ok with outer placement.
The heat paste I have is so old that it has split into "two phases".
Is there a recommended heat paste to use or just the usual "white stuff"?
MEPER, Make sure the screws that you use to secure the Mosfet and SIT to the heatsink go through the aluminum panel into the heatsink. That will apply pressure and provide good contact for thermal transfer to the heatsink. As for other screws, placement for function (thermal transfer) should be prioritized over placement for looks. 🙂
And as Zen Mod has advised many times before and I concur, locate the screws between fins so that you can drill and tap through and use longer screws, to minimize the chances of broken taps and stripped threads in the soft aluminum.
And as Zen Mod has advised many times before and I concur, locate the screws between fins so that you can drill and tap through and use longer screws, to minimize the chances of broken taps and stripped threads in the soft aluminum.
ZM made all the Errors in History
and then again
tmx to ZM, History repeats itself ......... and repeats ........
and then again
tmx to ZM, History repeats itself ......... and repeats ........
A quotation by Niels Bohr (now we have the 100-year anniversary from his Nobel prize in physics):
"An expert is a man who has made all the mistakes, which can be made, in a very narrow field"
"An expert is a man who has made all the mistakes, which can be made, in a very narrow field"
The screw placement below would be about the best placement to secure the panels ("1/3 split")? (just placed "by eye")
Then I think it is best to wait for the PCBs so I can ensure that the screws will not interfere with PCB screws ect.
Do we know the aluminium quality of the heatsinks?
Could it be:
Aluminium like this has a hardness close to normal steel and used by e.g., Shimano for their Dura Ace series. E.g., chains wheels are aluminium.
I will consider again making panel holes all the way through.,,,,,,,
Then I think it is best to wait for the PCBs so I can ensure that the screws will not interfere with PCB screws ect.
Do we know the aluminium quality of the heatsinks?
Could it be:
Aluminum alloy 7075, Al90Zn5.5Mg2.5Cu1.5Si0.5 ?
If this is the case, then I think threads into the heatsinks will be quite strong.Aluminium like this has a hardness close to normal steel and used by e.g., Shimano for their Dura Ace series. E.g., chains wheels are aluminium.
I will consider again making panel holes all the way through.,,,,,,,
A very minor update.
M4 hex-screws in various lengths which should cover all need for the amp arrived (also for the panel holes all the way through the heatsinks).
So that decision has been taken. I have made a couple of templates for marking holes.
Heatsink compound has also "landed".
Nice custom SMPS PSUs is on the way also.
So far so good.........hope they produce good compound in the UK......
M4 hex-screws in various lengths which should cover all need for the amp arrived (also for the panel holes all the way through the heatsinks).
So that decision has been taken. I have made a couple of templates for marking holes.
Heatsink compound has also "landed".
Nice custom SMPS PSUs is on the way also.
So far so good.........hope they produce good compound in the UK......
I plan to drill holes in the "far" corners of the panels and corresponding M4 threads in heatsinks. This just to hold the panels in place which makes a lot of "things" easier. Marking the holes at panels after drilling "through holes" in heatsinks, final assembly after applying compound etc.
Then I don't have to fight with "gravity of earth" too much.......during final assembly.
Then I don't have to fight with "gravity of earth" too much.......during final assembly.
Now the PCBs arrived from "ZM-Labs" with pre-mounted SMD's and most of the components to be installed.
In meantime I did a little mechanical work by drilling mounting holes in each corner of the heat spreader panels. Corresponding M4 threads has been made in the heatsinks. This is only for holding the panels into place which does making the "through holes" easier and also the final assembly. When the panels gets heat paste etc. it will be much easier to do final assembly according to my "prediction". The panels have a quite tight fit into the frames (top and bottom) so they must sit quite precise.
Will drill the "through holes" with panels mounted to get the holes to "line up" as exact as possible.
A few images to show the "progress" so far........
In meantime I did a little mechanical work by drilling mounting holes in each corner of the heat spreader panels. Corresponding M4 threads has been made in the heatsinks. This is only for holding the panels into place which does making the "through holes" easier and also the final assembly. When the panels gets heat paste etc. it will be much easier to do final assembly according to my "prediction". The panels have a quite tight fit into the frames (top and bottom) so they must sit quite precise.
Will drill the "through holes" with panels mounted to get the holes to "line up" as exact as possible.
A few images to show the "progress" so far........
Great progress!
I have got ZM-kits in mail-transit as we speak. So I will follow your lead and keep a close eye on your build so i dont have to do the same mistakes. Well thats If you do make som mistakes. Inspiration is a good thing too. ❄️❄️🙂🤚❄️❄️
☕
I have got ZM-kits in mail-transit as we speak. So I will follow your lead and keep a close eye on your build so i dont have to do the same mistakes. Well thats If you do make som mistakes. Inspiration is a good thing too. ❄️❄️🙂🤚❄️❄️
☕
Next step will be to mark the holes between the fins of the heatsinks. Six holes in each heatsink.
My plan is to mark the holes on "fin-side" and then drill all the way though heatsink and panel. This way I can better ensure holes are exact center between fins. I have drill-bits long enough so fins will not "interfere" with machine. Maybe I just make a "pilot hole" like 2.5mm or so from fin-side and then make the final 4.5mm hole from panel-side.
My plan is to mark the holes on "fin-side" and then drill all the way though heatsink and panel. This way I can better ensure holes are exact center between fins. I have drill-bits long enough so fins will not "interfere" with machine. Maybe I just make a "pilot hole" like 2.5mm or so from fin-side and then make the final 4.5mm hole from panel-side.
