Do you have the schematic for the above pcb design and also what are the OPS transistors?
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I only gonna cover Ostripper design's subject here he hasn't post any class H that I know also I'm only do modification of the layout that Mr. JKuteman did please keep subject relate to Ostripper design not out of subject related to other designs 🙂
I think all that he is saying is that can you combine the "power supply design" OF the green amp that Ostripper designed into the Arc welder schematic and therefore the PCB. Personally I would love to see that done. It would make a great or greater 400 watt amp. Thanks
I made the Grenamp layout a few months ago is double layer and after I tested sounds really good I like the design of Ostripper because you can try other types of IPS oh! I having seen OS's power supply design?
posting in all caps is against forum rules...
hey guys I have a question I recently purchase a drill press so I can work better the heat sinks drilling jobs the 4-40 screws can be use on power transistors like the MJL3281A On brand? or M3 screws?
The datasheet will normally give dimensions for transistor packages. Most metal tabbed transistors will have holes sized for a standard thread size plus an insulating bushing. I believe M3 is common for most packages, certainly TO247 and TO220 seem to have 3.5mm hole, which fits M3+bushing.
I prefer M3 screws and so do some of the guys who build amps in the USA.
For holes that go right through, I put the tap on a cordless drill, on a low setting.
For blind holes I put the tap in the drill press and turn slowly by hand. The drill press keeps the tap perpendicular but as you can guess it's a slow process.
I always use WD40 or a cutting fluid. Some times I stop the tapping to vacuum the junk that has fallen into the blind hole.
Experiment on some old aluminium first.
For holes that go right through, I put the tap on a cordless drill, on a low setting.
For blind holes I put the tap in the drill press and turn slowly by hand. The drill press keeps the tap perpendicular but as you can guess it's a slow process.
I always use WD40 or a cutting fluid. Some times I stop the tapping to vacuum the junk that has fallen into the blind hole.
Experiment on some old aluminium first.
i also use the singer sewing machine oil, tapmatic fluid, and wd40 when drilling ang tapping holes...
I've found the drilling is as important as the tapping. Use a sharp bit, tapping oil and go slowly. If you heat up the aluminium when drilling it will temper it and will make tapping it much more difficult.
I agree. I use soapy water for drilling, and tapping screw to fixing the transistors.
Sajti
Drill speed
Discussion here:
RPM to drill aluminum or steel?
If the formula is correct-
3mm = 0.11811"
600/ 0.11811 = 5080RPM for aluminium
Discussion here:
RPM to drill aluminum or steel?
If the formula is correct-
3mm = 0.11811"
600/ 0.11811 = 5080RPM for aluminium
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