TSC 55, does 18V batteries create more power, or longer run time?

WillB

Member
Joined
Sep 2, 2019
Messages
84
I use the 15v 5.2ah on my TSC 55
If I buy the 18V, will it increase the cutting power, or simply longer run time?
could use a little boost in power ;)
TY in advance...
 
I'd say you will see a more or less noticeable increase in RPM and power with the 18V batteries.

Not owning any 15V batteries, I can't test it for you.

Not sure, but I think [member=1619]SRSemenza[/member] also runs 15V in the TSC? Can you say something on this, Seth?

Kind regards,
Oliver
 
You'll see more speed/power but probably not a whole lot of extra run time.
 
Voltage should give you more power, but I couldn't tell you if that equates to RPM or torque? maybe both?
It is amperage that affects run time. That is why I use the 2ah batteries on all of my Makita impact drivers, drills, and compact routers. It makes them lighter, shorter, and just easier to handle overall, but I am in a cabinet shop using them a lot. I use them on a bench and surrounding area, not on a jobsite where run-time might be a bigger deal. If one runs down, the charger is right there and already plugged in. They charge quickly enough that it never matters in my situation.
 
six-point socket II said:
I'd say you will see a more or less noticeable increase in RPM and power with the 18V batteries.

Not owning any 15V batteries, I can't test it for you.

Not sure, but I think [member=1619]SRSemenza[/member] also runs 15V in the TSC? Can you say something on this, Seth?

Kind regards,
Oliver

When I had the Ti15 I was using 15v on the TSC55. Since I have switched to the Ti18 I am now using 18v on the saw. Unfortunately I did not / do not cut enough with it to have noticed a difference on power or run time to offer any comparison input.

Seth
 
I was working on the same general premise, i.e.  more voltage equals more rpm, torque or both.  But, I have been wrong many times..hopefully someone will ring in that has experienced the difference....
I was considering upgrading to the 18V batteries, cause too many of the 15V batteries fail.  Which is surprising to me, considering the tool can sit unused for months.  I always charge batteries while they are not in use.  Those considering the REB should think not just about the cost of batteries and chargers, but battery replacements, as the 18V are quite costly.  I keep 4 batteries so I can replace them when they drain.  This happens much faster when cutting 1" hardwoods vs. 3/4 ply.  No complaints about that, as its quite the task to ask from batteries.  The added convenience comes at a price!
 
You will get a bit more power - but not 18/15 = 20% more.

But you will stress the batteries less - 10 cells in pack versus 8 cells in 15V pack means 20% higher current load on the 15V pack cells. So longer life as well as more cycles out of the 18 packs.

If you are a heavy user, the 6.2 Bluetooth packs may be the best approach.

With higher capacity you buy not only individual runtime +20% or so, but ALSO the battery longevity is increased by more than 20%, think 25% or so. This is both a result of less frequent battery changes/cycles as well the 3.1 Ah cells being less loaded relatively ref amperage-to-capacity compared to the 2.6Ah cells in the 5.2 bats.

Overall, these aspects combined, you are likely to see anywhere from 40-60% better runtime and 60%-80% longer batteries lifespan with 6.2/18V versus a 5.2/15V packs.

On the durability, another thing that helps is to charge more often. It is better to charge the packs already when 50% empty instead of waiting for the pack to blink telling you it is spent too much. This can add a LOT of life to a pack.

A pack which will last 1000 cycles when cycled 95%-30% will easily last 2000+ cycles when cycled 95%-50% most of the time.

And even better is not to charge the bats 100% either - for most Li-Ion cells the most cycles one gets with something like 85%-60% cycles. That way the pack can give often in the range of 10,000+ cycles. The Festool chargers are smart, and never go 100% in the traditional sense. But it still means that pulling a pack off the charger when it shows
 
I believe if you look in the manual it will tell you what RPM you will get with each battery combination. Since you can mix 15 and 18 volt batteries there are a few combinations; single 18v, two 18v, single 15v, two 15v, one 15v + one 18v.
 
I just tested the TSC with 3 different pairs of battery packs.

2 each 15 vdc @ 3.0 Ah (actually 14.4 vdc)
2 each 15 vdc @ 4.2 Ah (actually 14.4 vdc)
2 each 18 vdc @ 5.2 Ah

With no-load the TSC will run on a single battery for any of the batteries listed. When the single battery is supplemented with a 2nd battery of the same type, the no-load blade speed does not change.

There's also NO difference in blade speed between any of the batteries or combination of batteries. So the blade turns at the same speed whether you use the 15 vdc @ 3.0 Ah or the 18 vdc @ 5.2 Ah.
 
Cheese said:
I just tested the TSC with 3 different pairs of battery packs.

2 each 15 vdc @ 3.0 Ah (actually 14.4 vdc)
2 each 15 vdc @ 4.2 Ah (actually 14.4 vdc)
2 each 18 vdc @ 5.2 Ah

With no-load the TSC will run on a single battery for any of the batteries listed. When the single battery is supplemented with a 2nd battery of the same type, the no-load blade speed does not change.

There's also NO difference in blade speed between any of the batteries or combination of batteries. So the blade turns at the same speed whether you use the 15 vdc @ 3.0 Ah or the 18 vdc @ 5.2 Ah.
I presume any differences are/will be in load speed.

The same way partially-full 18V packs do not give the same power output as a full ones the 15V ones will neither as even if the 15V packs gave same amperes, the voltage will be lower and the TSC current-limiter will kick in before the batteries are overloaded.

That said, I would expect 5-10% more torque/power under load with mostly-fresh packs. Nothing one can easily perceive as the fullness of the packs makes a bigger difference than that.
 
It all depends if the battery is the limiting part of the system.  If the battery has more power available from it than the tool draws when fully charged, then it can still deliver the same power as the voltage drops.  It's unlikely they design the tool around max voltage and peak current draw of the battery.  Motor is on the other side of switches from the battery, so in all likelihood it will be able to deliver full power thru some level of discharge of the battery.
 
DeformedTree said:
It all depends if the battery is the limiting part of the system.  If the battery has more power available from it than the tool draws when fully charged, then it can still deliver the same power as the voltage drops.  It's unlikely they design the tool around max voltage and peak current draw of the battery.  Motor is on the other side of switches from the battery, so in all likelihood it will be able to deliver full power thru some level of discharge of the battery.
Not sure, but since new I can feel the difference between a fully charged pack and one with "2 lights" which should be around 60% capacity or so.

Electric motors tend to have the biggest bite when slowed down and for best performance you would do some time of an integration of the current values over time and activate protections only when an over-spec current is in place over some prolonged period.

In my experience the saw can bog down temporarily and "get out of it" without protection engaging and yet protection can kick-off with less of a slow-down but continuous over a couple seconds at least. That would indicate that the motor can take pretty much anything the bats can provide and the protections are "smart" - aka thermal-budget-based, not simple current-based.

It make sense even on the chemistry/physics side if Festool was trying to get the most out of the system. Modern Li-Ion cells can handle huge currents for short periods but couple times lower for sustained load. The same is the case also for the engine parts and electronics. So it makes sense that for shorter bursts the batteries are the limiter while for longer work the motor/tool is the limiting factor.

Either way, I do not see a reason why would Festool gimp a 18V tool at design stage only to make sure it works no better than with the 15V batteries. It makes little business or technical sense to me.
 
Remember that Festool has MMC electronics (Aka load compensated torque/speed control) in most of their tools. Therefore they newer start at full speed or torque, the design of the electronics demands that there’s a reserve that can kick in when needed.
 
some great responses here, thx guys...
learned a lot more than the question I asked.
Will put that knowledge to good use.
anything to increase the life of these batteries is very helpful...
hard to watch the charger constantly to pull em at 5%, but when I can, I will...
I imagine Festool can not put a capacitor in the tool, for consistent power, as when you store the tool, the capacitor will have stored energy in it. 
I too can start to detect when batteries drop to 2/3 on meter...
I also notice sharp blades make a big difference, but that is true on either corded or cordless.
I am curious if a fully charged TS REB is more / less powerful than the TS55 corded.  I only own the TS75 corded. 
 
Well some of my questions were answered in this video...
seems my praise of the TS55 cordless is shared by someone who has compared it to all Festool saws....  a great video if u are in the market for a track saw.


 
WillB said:
some great responses here, thx guys...
learned a lot more than the question I asked.
Will put that knowledge to good use.
anything to increase the life of these batteries is very helpful...
hard to watch the charger constantly to pull em at 5%, but when I can, I will...
I imagine Festool can not put a capacitor in the tool, for consistent power, as when you store the tool, the capacitor will have stored energy in it. 
I too can start to detect when batteries drop to 2/3 on meter...
I also notice sharp blades make a big difference, but that is true on either corded or cordless.
I am curious if a fully charged TS REB is more / less powerful than the TS55 corded.  I only own the TS75 corded.

The energy density of a capacitor is very low, both per weight and per volume. Makes no sense to put that in a tool. That is besides the circuitry required to charge the cap and the incurred extra energy losses.
 
FestitaMakool said:
Remember that Festool has MMC electronics (Aka load compensated torque/speed control) in most of their tools. Therefore they newer start at full speed or torque, the design of the electronics demands that there’s a reserve that can kick in when needed.
Yes, that "extra range" available for exigencies was what I meant one loses when going with weaker batteries. Be they just drained,  15V etc.

My feel is the electronics taps into whatever the batteries can provide for a short period and then carry on. If the load does not subside the thermal/overload protections will kick-in. Having stronger batteries makes the saw feel "stronger" simply because it has more reserve to handle the "hard" spots but it does not really affect continuous load that much.
 
Back
Top