Mechanical reos will be seeing some upgrades
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That's unfortunate. We appreciate your updates Rob! We know this is beyond your control.
2mm is a bit on the large side for something like this, I would stay at 1/16" which is ~1.5mm, more than enough.
We aren't going anywhere Rob… duh. you'll just have to put up with us here for that much longer lol.
On my fused and pin modded Grand, I have been hung up on 26g nichrome, nice small micro about 6 wraps RM2, .40 Ohms is the perfect resistance imo… anything less and it sounds like a freeking geiger counter when you fire it sheeesh!
but at 0.40 it sizzles nicely … and in a few days the resistance creeps up in the .5+ range and then a few more days and time to change cotton and dry burn - that thick wire lasts months.
I have another Grand that's waiting to be put into the rotation ….with the new kit
On my fused and pin modded Grand, I have been hung up on 26g nichrome, nice small micro about 6 wraps RM2, .40 Ohms is the perfect resistance imo… anything less and it sounds like a freeking geiger counter when you fire it sheeesh!
but at 0.40 it sizzles nicely … and in a few days the resistance creeps up in the .5+ range and then a few more days and time to change cotton and dry burn - that thick wire lasts months.
I have another Grand that's waiting to be put into the rotation ….with the new kit
Something I'm wondering is what voltage do you see at the RM2 coil posts after your modifications and with a fresh battery? My little fuse mod only allows me to see about 3.75 to 3.85 volts at the posts.
Thanks.
I haven't done any v-drop tests although the person that modded my Grand (Pdib) did… I just know that it vapes terrific
fwiw: and never had a short
even .35 ohms fires up but too much heat (and noise) for my taste.
don't know if this helps
3.75-3.85 doesn't sound bad at all for something in the sub ohm range but it all really depends on the battery you're using and the resistance of your coil. that's not really telling much of anything because you are measuring the resistance of the mod and the battery at the same time.
the right way to measure voltage drop is: battery is 4.05 v at rest. fine, now fire the mod and check the voltage right at the battery. that 4.05 might drop to 3.85 under load at the battery. this has nothing to do with the mod, this is just what that particular battery will drop to under this particular load. you then measure at the atty coil posts for 3.75v. in a case like that the voltage drop OF THE MOD would be only .1v at a .45 ohm load in this example. don't include the battery drop in your numbers it doesn't really show the potential of the mod itself. you need to measure the difference while firing at the battery, then at the atty, the difference between these 2 is the actual voltage drop of the mod.
an example. I measured my stock reo woody the other day. battery at 4.11 at rest, under firing the battery drops to 3.88, at the atty I'm getting 3.75, so were talking a voltage drop of .13 that's my stock wood reo with tin foil shoved in the spring, without the tin foil and running it on the spring itself the atty measured at 3.58 for a total of .3v drop, more than double. this is only with a .75ohm load though, as the load increases obviously the voltage drop of the mod itself will increase too, but so will the battery drop. high drain batteries will drop less than a battery rated at less amps delivery but they all will drop some, hell even a car battery drops in voltage as the car is cranked, but there too,while cranking measure at the battery, then at the starter, the difference is the voltage drop. comparing cranking at the starter vs what the battery is at rest tells nothing absolute. sorry to get all technical on you, just trying to help
Spot on Turbo. I was going to type up a reply, but knew how long it was going to take, and abandoned it. You explained it better than I could have anyway
From those voltage measurements you gave, the resistance of the battery spring and the resistance of the rest of the mod (including the switch contacts, wiring, battery contacts, 510 connector and any resistances in the atty) can be calculated.
From those voltage measurements you gave, the resistance of the battery spring and the resistance of the rest of the mod (including the switch contacts, wiring, battery contacts, 510 connector and any resistances in the atty) can be calculated.
How do you do that in the above blue?3.75-3.85 doesn't sound bad at all for something in the sub ohm range but it all really depends on the battery you're using and the resistance of your coil. that's not really telling much of anything because you are measuring the resistance of the mod and the battery at the same time.
the right way to measure voltage drop is: battery is 4.05 v at rest. fine, now fire the mod and check the voltage right at the battery. that 4.05 might drop to 3.85 under load at the battery. this has nothing to do with the mod, this is just what that particular battery will drop to under this particular load. you then measure at the atty coil posts for 3.75v. in a case like that the voltage drop OF THE MOD would be only .1v at a .45 ohm load in this example. don't include the battery drop in your numbers it doesn't really show the potential of the mod itself. you need to measure the difference while firing at the battery, then at the atty, the difference between these 2 is the actual voltage drop of the mod.
an example. I measured my stock reo woody the other day. battery at 4.11 at rest, under firing the battery drops to 3.88, at the atty I'm getting 3.75, so were talking a voltage drop of .13 that's my stock wood reo with tin foil shoved in the spring, without the tin foil and running it on the spring itself the atty measured at 3.58 for a total of .3v drop, more than double. this is only with a .75ohm load though, as the load increases obviously the voltage drop of the mod itself will increase too, but so will the battery drop. high drain batteries will drop less than a battery rated at less amps delivery but they all will drop some, hell even a car battery drops in voltage as the car is cranked, but there too,while cranking measure at the battery, then at the starter, the difference is the voltage drop. comparing cranking at the starter vs what the battery is at rest tells nothing absolute. sorry to get all technical on you, just trying to help
on a reo it's easy, you can get at the battery while in use with the door off. on most tube mods it's much more difficult and sometimes not really even possible or practical and would take much more complicated test setups.
I have seen some even alter a mod making holes in it just to be able to get these measurements for bragging rights or to validate how low the voltage drop of the mod itself is. whenever you see claims of very low drop or some even claiming 0 loss there all measured this way, it's the only way to isolate the drop of the mod without also including the drop of the battery which has nothing to do with the mod itself. all batteries will show lower voltage under load
I have seen some even alter a mod making holes in it just to be able to get these measurements for bragging rights or to validate how low the voltage drop of the mod itself is. whenever you see claims of very low drop or some even claiming 0 loss there all measured this way, it's the only way to isolate the drop of the mod without also including the drop of the battery which has nothing to do with the mod itself. all batteries will show lower voltage under load
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other than bragging rights true voltage drop will be at the end its like a car say the car has 300 horsepower the hp at the axels will be less from drivetrain loss the loss of the exact same car with 4 wheel drive will be even more as the car is pushing more mechanical gear around 300 hp isn't gonna do squat if you can't get most of it to the wheels i.e. the coil
I don't find it very easy to get to the positive (top) contact of the battery on a Reo, do you take the delrin cover off to do this? On a Woodvil its no problem because there are tabs of metal at each end of the battery that are easy to put the multimeter probes on. And of course, a third hand to press the fire button would be nice
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I haven't tried it on a stock metal reo mine didn't stay stock long enough to test it, but I'd think a small pin probe should work, either that or pop the delrin cap out if your lead doesn't fit. it's real easy to do on the woody
of course the truth is you can measure as a whole too and it'll still give you a really good idea, especially when it's just comparing one mod to the other with same coil, same battery. that's why I said 3.75-3.85 don't sound bad at all assuming an upper range sub ohm build of .7-.8 or so.
I'm not saying you have to do this or even should, but my point is if you use a crappy battery and a higher amp load you may fool yourself into believing the mod has a lot of voltage drop even if it really has very little .
of course the truth is you can measure as a whole too and it'll still give you a really good idea, especially when it's just comparing one mod to the other with same coil, same battery. that's why I said 3.75-3.85 don't sound bad at all assuming an upper range sub ohm build of .7-.8 or so.
I'm not saying you have to do this or even should, but my point is if you use a crappy battery and a higher amp load you may fool yourself into believing the mod has a lot of voltage drop even if it really has very little .
the reason I posted this stuff is because the question was "...only allows me to see about 3.75 to 3.85 volts at the posts" seeming to imply that he should see much closer to battery at rest voltage if there is little loss. just trying to show that you should expect to see much lower and that this doesn't necessarily indicate a deficiency, it's normal even for a mod with very little loss, and heres why....
I still have no idea, sorry. I need to know where the probes go, do you fire the mod, is the rba on with a coil etc. Sorry I am ignorant but persistent.
sorry man, you place both leads at the 2 ends of the battery, it'll show resting voltage, you then fire the mod with the leads still there, it'll show battery voltage under load. you then move the leads to the coil posts and fire, reading the voltage to the coil while firing. you now subtract the coil voltage while firing from the battery voltage while firing, and this will show you true voltage drop of the mod and the mod alone.
a mod can have zero loss and still show a total of well over a .5v drop, depending on the load and the battery. you are seeing voltage drop but the mod actually has none. how can you know that when you see a .5v loss?
a mod can have zero loss and still show a total of well over a .5v drop, depending on the load and the battery. you are seeing voltage drop but the mod actually has none. how can you know that when you see a .5v loss?
Mama you just got the "chuckle of the year so far" award from me.
Got to clean the monitor off now.
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