How do you make short, repeated cuts with the Kapex?

[Allano]

When this "rule" can't be followed (e.g., due to workflow consideration), I use a spring-loaded flip stop:

I had to look at that image for several minutes, being fooled by perspective in two different way before it finally clicked. And ironically, I have a piece exactly like it in my own workshop. This is a hardwood patio plank, which you have split longitudinally, right?

But I still don't get how the spring loading works. Could you explain a bit more?

 

[MikeGE]

I had to look at that image for several minutes, being fooled by perspective in two different way before it finally clicked. And ironically, I have a piece exactly like it in my own workshop. This is a hardwood patio plank, which you have split longitudinally, right?

But I still don't get how the spring loading works. Could you explain a bit more?

 

I had to look at the image for a while before I realized what it was.  I assume the spring is providing enough friction on the flipper to keep it in place once it is moved out of the way.

 

[Packard]

Snip
The one rule to never brake though is simple. Clamp the piece that is between the stop and the saw. This is where the potential bind takes place. The other piece is "loose", so no bind exists there.Snip

When this "rule" can't be followed (e.g., due to workflow consideration), I use a spring-loaded flip stop:

[attachimg=1]

I've seen that rule broken by some YouTubers, and viewers who unknowingly copy them are at the mercy of the kickback God.

This resembles my DeWalt chop saw.  Mine does not have a zero clearance insert and even if it did, it would not prevent tear out at the rear of the cut.  When I need clean, repetitive cuts, I make a sacrificial zero clearance fence.  And if it is repeated cuts, I build in a stop, usually screwed in place. 

By making a zero clearance fence, I can get clean cutoffs on both sides of the blade. 

I’ve tried Fastcap’s zero clearance tape, but it gradually opens up.  I don’t know why.  I checked for run-out on the blade and I am not seeing any. 

If the tear out is not a concern, then I will skip that step.  Or I will cut it on the table saw which gives cleaner cuts. 

Making an L-shaped fence for the chop saw takes just a few minutes and uses scrap that I generate anyhow.  I unusually use. 3/4” sheet stock and assemble with screws or pocket screws.  I don’t think this would work for a sliding chop saw though.

 

[Cheese]

When this "rule" can't be followed (e.g., due to workflow consideration), I use a spring-loaded flip stop:

[attachimg=1]

I've seen that rule broken by some YouTubers, and viewers who unknowingly copy them are at the mercy of the kickback God.

Interesting Chuck...I wonder if a torsion spring would be a better application?

I've noticed recently that several metal working chop saws have added clamps to secure the material on both sides of the cut.  I presume this works well because there is no spring-back associated with metal stock.

[attachimg=1]

[attachimg=2]

 

[rmhinden]

You also have one of those "million dollar sticks" in there too, no "clamp".  That is what I do with smaller parts too, except mine is wood (and shop-made) It is rare that I use the clamp (for parts anyway) I mostly use it for holding jigs/fixtures, like the 45degree stop

The tape is ok, but not as "positive", plus you have to struggle with moving it to the exact point. Micro adjusting is not so easy either.........price is very attractive though.

The "million dollar stick" was not needed in the picture.  I would only using that if the board was too short to clamp.

I was concerned about how accurate using the tape would be too, but I found it works surprising well.  Also, what I was doing, it was more important that all of the pieces be the same size vs. some exact measurement.

Bob

 

[ChuckM]

When this "rule" can't be followed (e.g., due to workflow consideration), I use a spring-loaded flip stop:

I had to look at that image for several minutes, being fooled by perspective in two different way before it finally clicked. And ironically, I have a piece exactly like it in my own workshop. This is a hardwood patio plank, which you have split longitudinally, right?

But I still don't get how the spring loading works. Could you explain a bit more?

This illustration is from the Australian Wood Review magazine:

[attachimg=1]

I made mine with a hardwood flooring left-over piece. Any hardwood lumber scrap will do.

Hope it helps. I also use the flip stop on the table saw crosscut sled.

 

[ChuckM]

snip.
This resembles my DeWalt chop saw.  Mine does not have a zero clearance insert and even if it did, it would not prevent tear out at the rear of the cut.  When I need clean, repetitive cuts, I make a sacrificial zero clearance fence.  And if it is repeated cuts, I build in a stop, usually screwed in place. 

By making a zero clearance fence, I can get clean cutoffs on both sides of the blade. 

I’ve tried Fastcap’s zero clearance tape, but it gradually opens up.  I don’t know why.  I checked for run-out on the blade and I am not seeing any. 

If the tear out is not a concern, then I will skip that step.  Or I will cut it on the table saw which gives cleaner cuts. 

Making an L-shaped fence for the chop saw takes just a few minutes and uses scrap that I generate anyhow.  I unusually use. 3/4” sheet stock and assemble with screws or pocket screws.  I don’t think this would work for a sliding chop saw though.

That was my old saw, sold after I acquired the Kapex.

I have not had the issue you had with the Fastcap tape. I did replace it once due to wear and tear and making some bevel cuts. I have to fix the ZCI on my SawStop regularly compared to the Kapex tape.

I have an L-shaped auxiliary fence, too, but I use it to handle small trims and pieces or precision work.

[attachimg=1]

 

[ChuckM]

When this "rule" can't be followed (e.g., due to workflow consideration), I use a spring-loaded flip stop:

[attachimg=1]

I've seen that rule broken by some YouTubers, and viewers who unknowingly copy them are at the mercy of the kickback God.

Interesting Chuck...I wonder if a torsion spring would be a better application?

I've noticed recently that several metal working chop saws have added clamps to secure the material on both sides of the cut.  I presume this works well because there is no spring-back associated with metal stock.

[attachimg=1]

[attachimg=2]

Could you reload your images? They don't seem to show up.

 

[Cheese]

This illustration is from the Australian Wood Review magazine:

[attachimg=1]

Hope it helps. I also use the flip stop on the table saw crosscut sled.

Thanks for that Chuck...that makes more sense as you can adjust the amount of resistance when moving the stop arm.

 

[Michael Kellough]

So far I have gotten away without needing any special fixture to deal with small off-cuts when a hard stop is used to set length. Usually they are small enough that simply waiting for the blade to stop spinning before removing the piece is sufficient. The set of the teeth provides enough clearance that the off-cut is not disturbed. But you have to also remember not to let the saw rise before removing the piece.

If I needed such a fixture I think a cam would be the best way to set the stop for positioning prior to cutting and would quickly allow slack to cut safely.

 

[ChuckM]

Snip.

The "million dollar stick" was not needed in the picture.  I would only using that if the board was too short to clamp.

I was concerned about how accurate using the tape would be too, but I found it works surprising well.  Also, what I was doing, it was more important that all of the pieces be the same size vs. some exact measurement.

Bob

It probably is not suitable for stack cutting and long, heavy boards. My concern is the need to ensure the tape is perpendicular to the fence. If the material is not butting against the full length of the tape, but only part of it (the contact point), after a few cuts, there's a risk of the contact point being moved.

 

[Cheese]

My concern is the need to ensure the tape is perpendicular to the fence. If the material is not butting against the full length of the tape, but only part of it (the contact point), after a few cuts, there's a risk of the contact point being moved.

My solution to that would be to put down the 3 layers of tape and then trim the tape edge relative to the fence using a small square and scalpel.

However, I think for repetitive quantities above 10 or so, you risk slightly rolling over the top layer of tape which does move the contact point. For that reason and the simplicity of it all, I'd still prefer wood or aluminum as a hard stop.

When I use a hard stop, I put significant side thrust on the material to be cut to ensure it comes into good, firm contact with the hard stop. That method alone would not allow me to use multiple tape layers. That's the reason that despite the cutting fuzz that can be seen in the photo of the dowel, the high side force put on the dowel mitigates most of the potential dimensional issues.

 

[Packard]

I recently had to cut lengths of 1/4” diameter dowels to 1-7/8” for axles for toy cars.  I cross drilled a 3” nominal (2-1/2” actual) piece of 3/4” poplar.  The hole was one size larger than 1/4” to make slipping in the dowels easier.

I made a cut 1-7/8” from one side. 

I slipped in the dowel to be flush with the edge of the poplar piece, and made the cuts. 

Both sides of the cut were fully supported so no tear out around 360 degrees. 

It was faster and easier to use on the table saw with the fence used to hold things square and for the sliding action. 

The problem with the set ups I see, is that you will end up with tear out at the rear of the cut with a chop saw.  Which means you will have tearout at both ends of the pieces.  If it is a fussy part, a dedicated fence that prevents tearout around 360 degrees is preferred (by me).

ChuckS’ sacrificial fence being the exception. 

If I am making many cuts, then I make a similar fence and toss it when I am done. 

For reasons that escape me, my dedicated 45 degree angle sliding table miter saw leaves zero tearout even on the most elaborate picture frame molding.  It could be that ghastly expensive blade that cost $200.00 in 1982 ($665.00 in current dollars).  I don’t think I could find a miter saw blade for $665.00 nowadays.  At any rate, for 45 degree miters, i migrate the work to the sliding table saw.

 

[smorgasbord]

This resembles my DeWalt chop saw.  Mine does not have a zero clearance insert and even if it did, it would not prevent tear out at the rear of the cut.  When I need clean, repetitive cuts, I make a sacrificial zero clearance fence.  And if it is repeated cuts, I build in a stop, usually screwed in place. 

By making a zero clearance fence, I can get clean cutoffs on both sides of the blade. 

I’ve tried Fastcap’s zero clearance tape, but it gradually opens up.  I don’t know why.  I checked for run-out on the blade and I am not seeing any. 

I once ranted about SCMS and Zero Clearance Inserts here.

1) There is almost never any tear-out on the bottom of a SCMS  cut, just like there's almost never any tear-out on the top of a tablesaw cut. If you stand on your head, the geometry of the cut is the same. On miter saws, there is some cutting geometry differences between the chop action and the sliding action that affects tear-out. Basically, any time the teeth exit the workpiece without support you can get tear out, but never on entry into the workpiece. Supporting the workpiece right up to the kerf can greatly reduce tear-out on teeth exits.

2) As is noted by others, the back fence is where tear-out often occurs, yet there are very few commercial solutions (Coliflower cube is one) for this. I think people tend to focus on the bottom insert due to all the tablesaw inserts that do work, but again, the geometry is different.

3) As to why a ZCI or t ape would open up, as I said in the linked post, the only mechanisms I can see are: 1)Flex in the supporting arm and structure, and 2)Blade deflection, especially in thick cuts or cutting too quickly. But, I've learned to stop worrying about that, since there's no tear-out even with the stock wide insert openings. However, flex is not good for cut accuracy, so now I worry about that.

4) On my Bosch SCMS, there's apparently no adjustment for "crabbing." This is where the sliding action isn't perfectly parallel to the blade. This can affect accuracy if your cut is a combination of chop and slide, but if only chop the slide doesn't matter, and if only slide then it mostly adds a tiny vertical curve (and I do mean tiny), but also can affect tear out.

 

[ChuckM]

Snip.
You also have one of those "million dollar sticks" in there too. no "clamp".  That is what I do with smaller parts too, except mine is wood (and shop-made) It is rare that I use the clamp (for parts anyway) I mostly use it for holding jigs/fixtures, like the 45degree stop
Snip.

As good as the "10 Mn $ stick" is, I needed to improve it by applying hockey tape to the long handle so I can grip it well when holding the stick to use the fork end to hold down something.

[attachimg=1][attachimg=2] 

 

[SoonerFan]

[member=44099]Cheese[/member] did the cut length happen to increase sequentially by .001 each cut from 2.016 to 2.020?  Decrease from 2.020 to 2.016 by .001 per cut?  Were the cuts lengths not in a sequence and just random?  Amazing close tolerance and I am just curious.  Thanks. 

 

[Cheese]

[member=44099]Cheese[/member] did the cut length happen to increase sequentially by .001 each cut from 2.016 to 2.020?  Decrease from 2.020 to 2.016 by .001 per cut?  Were the cuts lengths not in a sequence and just random?  Amazing close tolerance and I am just curious.  Thanks.

Just random... [smile]

After I cut the pieces, I placed them on the bed of the lathe for some secondary operations, it was at that moment that I noticed that they appeared to be exactly the same length...that prompted the question "I wonder if they are?" so I hauled out the dial calipers. [big grin]

 

[SoonerFan]

[member=44099]Cheese[/member] did the cut length happen to increase sequentially by .001 each cut from 2.016 to 2.020?  Decrease from 2.020 to 2.016 by .001 per cut?  Were the cuts lengths not in a sequence and just random?  Amazing close tolerance and I am just curious.  Thanks.

Just random... [smile]

After I cut the pieces, I placed them on the bed of the lathe for some secondary operations, it was at that moment that I noticed that they appeared to be exactly the same length...that prompted the question "I wonder if they are?" so I hauled out the dial calipers. [big grin]

Thanks for letting me know.  I would have perplexed had the heights increased or decreased exactly .001 between each cut. 

 

[Cheese]

Thanks for letting me know.  I would have perplexed had the heights increased or decreased exactly .001 between each cut.

I would also have been perplexed if the thicknesses were reduced by .001" with each successive cut. That would have potentially been a rabbit hole I fell into and I never recovered from.  [smile]

It was an interesting revelation as I now feel confidant that with the substitution of aluminum positive stops, cutting hardwood instead of fir and a few additional tweaks, a tolerance range of .002"-.003' could be routine. That's pretty damn good considering it's easy peasy if your chop saw skills are consistent. But that's another factor.  [sad]