Table Saw Infeed Speed

[onocoffee]

Last weekend I took a class at my local Woodcraft and we were cutting parts for the build out of 8/4 hard maple - both long 24" rips and 6-8" crosscuts (with a sled).

In my garage hobby-ist setup, I have the small SawStop CTS, DeWalt 735 and Cutech 8" jointer with a Ridgid shop vac. At the Woodcraft, they have a SawStop 5hp ICS, Powermatic 15HH planer, Powermatic 6" jointer and Rikon single stage dust collection.

When I cut on the CTS, I usually have a steady pace but I'm not pushing very fast or hard most of the time. I find overall that the CTS has been a solid companion and I haven't found myself wanting. However, as I watched some of the other students making their cuts, I noticed some of them had burn marks that I was attributing to too slow a feed rate. When i went to cut my pieces, I figured I would take the 5hp for a ride and I pushed my pieces through that saw with a speed and force that don't think I would use on the CTS. My thinking is that the 5hp has to be able to take it. Happily, there were no flying workpieces and no burns.

But I don't know if this is the correct approach. Should I be pushing the feed harder and faster? By comparison, the CTS is about 1.5hp.

I mentioned the other equipment because it's been awhile since I've worked in another workshop than my own and I was quite surprised at how relatively quiet it was. The 15HH, ICS and jointer are "quiet" enough that you could forego hearing protection and not feel pain (definitely not so in my shop). At one point, all of them (and both Rikon collectors) were running simultaneously and I took a reading with my phone app: 85/86db.

 

[Hipplewm]

Going from my old DeWalt contracter saw to a 3HP sawstop certainly made almost everything faster - I could def push faster and cut faster...
BUT
For me the blade makes more difference - going from a 40T blade to a 24T and then ripping wood, I can push a heck of a lot faster - I never tried to change blades on my old saw - so not sure how that would affect it.... Having the ability to clear all that sawdust quickly and effectively makes a huge difference for me.

I dunno, nothing scientific etc - my DeWalt was also 8.25", SS is 10" so it will cit 8/4 with EASE - the DeWalt was MAXED out trying to cut it....

 

[Packard]

Is your blade clean? Is parallel to the fence? Are you using a splitter?

My saw will bind and burn on long cuts unless I put a spacer at the start of the cut. My 30 year old saw does not have a splitter that raises and falls, I have to bolt is or unbolt it. I use a device that has little splitter pieces that the cut carries off as it it progressing.

My feed rate is based on “feel” (resistance to the feed). I have found that it is the least likely source of burned edges.

 

[onocoffee]

My blades are clean and sharp. I also routinely change blades to meet the cut. While everyone else was gingerly feeding their pieces, I was jamming them HARD - just because I wanted to see what a 5hp ICS could do. It never slowed down.

The CTS is a 10" like the ICS and I haven't really had any issues with it as far as power goes. I just am pretty sure that I could not feed 8/4 hard maple at the rate I was feeding it through the ICS.

 

[Frnk]

There are formulas for this.

Two formulas are used frequently in industrial settings. This one is similar to how the cutting speed for CNCs might be calculated. It applies for methods with tools that have multiple cutting edges.

The feed rate:

Vf = fz × z × n

Vf = Feed rate (in mm/min or m/min) – the linear speed at which the workpiece advances into the saw blade
fz = Feed per tooth (in mm/tooth) – material-dependent advance per cutting edge per revolution
z = Number of teeth on the blade
n = Spindle speed or RPM (in revolutions per minute)

And then this one for the cutting speed:

V(c) = d × π × n / 60.000

V(c) = Cutting speed (in m/s)
n = RPM
d = blade diameter

This formula calculates the cutting speed (also called circumferential or peripheral speed) of a rotating tool like a table saw blade. It determines how fast the blade’s teeth travel through the material at the cutting edge, ensuring material-appropriate conditions to avoid burning, dulling, or poor cuts.

Here’s an example for how it works in practice:

1. Choose material-specific cutting speed (e.g., softwood: 40–60 m/min; hardwood: 30–50 m/min)
2. Solve for n (RPM)
3. Plug n into the formula for feed rate

Now you know what your optimal feed rate would be.

Or, you can skip the math and do what you've done: adjust the feed rate based on feedback like burn marks.

 

[Frnk]

But I don't know if this is the correct approach. Should I be pushing the feed harder and faster? By comparison, the CTS is about 1.5hp.

Apologies, I got carried away by all that math and ignored your original question: how is this related to HP?

I had to look up the formulas in teaching materials. I could copy and paste them here, but they're super nerdy and complicated. And don't help much outside of industrial settings, I believe. They rely on a ton of additional data like depth and width of cut, tooth geometry, number of teeth engaged, cutting force (material specific) and something called a "blade factor" …

But what the formula would show is this: does a specific motor have enough power to allow ideal infeed speed? If it does not, the saw stalls.
Then infeed speed Vf could then be calculated to mach the motor's max output.

Just for fun, I applied the formula in an example for the CSC SYS, because that’s the saw I have available to me:

168 mm blade diameter, 6,800 RPM no-load speed, 1.8 mm kerf, for a typical oak rip at max depth ~48 mm, assume NT=42 teeth (fine cut standard), feed rate = 3,000 mm/min (conservative for battery)

Result: required HP ≈ 0.8–1.2

So, good news, the CSC SYS is suitable for this type of cuts with a feed rate of 3,000 mm/min (Festool rates it equivalent to ~1.5–2 kW)

 

[Frnk]

And since this is so much fun, here’s some Python magic for the original scenario:

For 8/4 (50.8 mm) hard maple on a SawStop 5 HP ICS (10” blade, ~4,000 RPM loaded, 3.125” max depth), ripping 24” long and 6–8” crosscuts:

Max Feed Rate (5 HP limit, no overload):
Rips: 10,000–10,700 mm/min (33–35 FPM)
Crosscuts: 7,500–8,000 mm/min (25–26 FPM)

Recommended Feed:
Rips: 6,000–8,000 mm/min (20–26 FPM)
Crosscuts: 4,500–6,000 mm/min (15–20 FPM)

That’s enough math for me today — it’s making me feel dizzy.

 

[flair woodworks]

I would like to add that the higher the hook angle (e.g. 20 vs 0, or -5), the more the blade helps feed the materials and the less you need to push. Switching from my usual aggressive ripping blade with probably a 20 degree hook angle to my -5 degree dado stack makes a BIG difference in both the feed rate and amount of effort required to push the wood through!

 

[ChuckS]

Going from my old DeWalt contracter saw to a 3HP sawstop certainly made almost everything faster - I could def push faster and cut faster...
BUT
For me the blade makes more difference - going from a 40T blade to a 24T and then ripping wood, I can push a heck of a lot faster - I never tried to change blades on my old saw - so not sure how that would affect it.... Having the ability to clear all that sawdust quickly and effectively makes a huge difference for me.

I dunno, nothing scientific etc - my DeWalt was also 8.25", SS is 10" so it will cit 8/4 with EASE - the DeWalt was MAXED out trying to cut it....

This.

You don't need a 5 HP saw to rip thick lumber. My Woodworker II 20 T rip blade looks at wood as butter on my SS PCS (1.75 HP).