Alan B wrote:Very nice. Very dangerous. Not really the right tools for the job. Glad it didn't blow up on you in the saw.
Fine tooth carbide blades cut aluminum in a table saw much better than this, but it is still dangerous. I had a block of plastic move just a little and it ruined the blade and the saw, bent the axle and threw the workpiece.
Get a friend with a mill.
Don't try this at home, folks.
And, how is this heatsink working out? Did it solve the problem?spinningmagnets wrote:If you don't mind me asking, what are your max amps?With the thinner baseplate of those heatsinks, they overheat after multiple starts at my power levels
Ah yes... heavier load on direct drive motors designed for higher speeds - forgot how peaky those amps get. I'm 72kg, pedal on start and have been using exclusively geared motors. I also have the phaserunner to ease in over 1000ms, so the only time I get heat issues is long hills at full throttle.MrDude_1 wrote: Sunder:
There are a couple problems with those heatsinks. I already tried them.
First problem is the phaserunner itself. You use the most power pulling away from a stop. That is also when there is the smallest amount of air. The reason I started using big chunks of aluminum, is that it can draw all the heat away and absorb it... then before it really warms up you're moving with airflow again. With the thinner baseplate of those heatsinks, they overheat after multiple starts at my power levels. This may not be a problem for you, depending on how you're using it.
To be honest, I've never had a problem with that. I just put it in a vice and drill with a hand drill. The ones I've used, the fins aren't quite as fine as in the photo, but an M3 bolt with a screw head had no problems fitting. A hex head might have.MrDude_1 wrote: The second problem with putting that heatsink on is drilling the fins.
If an accident was going to crush the fins and damage the phaserunner behind it, I'd be more worried about my own health than my kit. as I said, it would only be against loose stones - more cosmetic than functionally damaging.MrDude_1 wrote: The final problem is your mounting idea. While its nice to have the fins forward and I know the idea is to protect the phaserunner,
the phaserunner is set as high as the BACdoor software will let me. I forget what it is. I see 65+a peaks on the CA but they are brief. WOT from a stop. at full speed it sustains between 40 and 58 constant depending on wind, slight uphill/downhill (so slight, you cant see it or tell when walking) however I go with traffic, so usually not flat out once I catch a car.spinningmagnets wrote:If you don't mind me asking, what are your max amps?With the thinner baseplate of those heatsinks, they overheat after multiple starts at my power levels
Hey, just wanted to congratulate you on a pretty sweet job of a DIY heatink build, having cut my share of aluminum stock on a table saw I know that's doable but no small feat.MrDude_1 wrote:So this is how I made a custom heatsink for my phaserunner controller.
Thanks, it means a lot to hear that from you.justin_le wrote:Hey, just wanted to congratulate you on a pretty sweet job of a DIY heatink build, having cut my share of aluminum stock on a table saw I know that's doable but no small feat.MrDude_1 wrote:So this is how I made a custom heatsink for my phaserunner controller.
This makes complete sense to me.. since I had it "warmed up" from rolling down the road, pulling away from a stop I am well over that 50a mark... and it cuts out on me. With the heatsink it stays cooler from the start, and then it can take the full amperage starting off again. I'll go checkout the main thread now.justin_le wrote: Anyways I had mentioned quite some time ago that we would be doing thermal rollback tests on the Phaserunner controllers inside the wind tunnel to quantify how long it takes for them to overheat at full phase current with and without extra heatsinks, and also determining what the resulting continuous phase current is like, and we finally got around to that this summer.
I'll have the full test details and results in the main Phaserunner thread, but the quick summary is that with a heatsink as shown here at 30-40kph ebike speeds, the continuous phase current capability is about 70 amps, while if you just have the bare phaserunner strapped to a tube then it's more like 50 amps.
When we ran the controllers with 80 amps of phase current, they would take 2 minutes to go from room temp to thermal rollback on the bare controller, and more like 4-5 minutes with the extra heatsink. I actually was expecting the bolt on heatsink to make a more substantial difference than this in the time to reach thermal rollback, but results are results! Anyways I'm glad to hear that this has completely eliminated thermal rollback on your own setup. It's good to see firsthand that the phaserunner so modified copes will with setups that are in the 2-4kW continuous power range.
These are AWEsome results! Heatsinks have no moving parts, they never "wear out", and they are completely water-proof in a monsoon. Not all frames are aluminum, but alloy is the growing frame material of common bicycles. This opens up the option of the frame becoming an additional heat-sink.I actually was expecting the bolt-on heatsink to make a more substantial difference than this in the time to reach thermal rollback, but results are results!
The cranks cant weigh that much.. they're plastic!skeetab5780 wrote:Nice DIY heat sink and nice bike! I have the same one
Need to upgrade that shock next and the crankset weighs like 10 pounds so it needs to go!
what is the controller max volt and amps? neat little thing
Wow, that is quite the hunk of aluminum Spinningmagnets!spinningmagnets wrote:More pics to come. The plan it to mount it to the aluminum seat-tube on the frame. I assume the mass of this heat sink is enough it wouldn't matter if it was bonded to an aluminum frame, but it couldn't hurt, right?
Yeah, we were actually trying hard to fit an M5 thread for mounting but the tolerances across the board were a little too tight unless we expanded some other dimensions which we didn't want to do. However, for people in the US who can't easily access metric hardware, you could probably drill and retap the hole to the #10-32 thread size without issue. It might poke through a bit on the sideways through hole for zap straps but that wouldn't matter:Just a side-note, the threads to the holes on the underside of the stock baseplate are 4mm X 0.70, not easy to find at the corner hardware store.