Uneven planing with HL 850

[Viljo]

I bought an HL 850 from local Festool (Black Friday sales). Finally tried it last week. I noticed that it takes a much deeper cut on one side. When put in the park position it still cuts about 0.5mm from one side and none from the other. I, obviously, took it back for service and I just got a call from them. They claim that it cannot be fixed. Their assumption is that there has been a defective batch of moldings and all current planers are affected by it. Their suggestion is rescission of sale. Which of course would be fair, but I would rather have a working planer.

When I was checking it before taking it back, I noticed the groove for the blade in the planing head is deeper on the other side. There is actually over 0.5mm difference from side to side. Could someone with an HL 850 check if the groove is constant depth or sloped? To my understanding the service did not check this even though I told them about the possible problem.

 

[luvmytoolz]

I'm trying to understand what the issue is, but not really getting it. The HL850 blade is curved so it takes a shearing cut. I'd find it strange they produced a batch of HL850's, which haven't been available for years, that the head has a manufacturing defect that hasn't been discovered till now.

Has the blade actually been correctly seated in the head, it's not sticking up one end a bit?

 

[Viljo]

Although the actual sharp part is curved the bottom of the blade is straight. If the groove is sloped, then to me it seems that the planing will most likely be uneven.

The blade was seated firmly into the groove. I noticed that one side of the blade was protuding above to the back of the sole, whereas the other side was below that (checked by having a straightedge on the back of the sole and rotating the planing head).

 

[luvmytoolz]

So is the issue just the planer head/blade, or is it the base?

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

The HL850 is by far the best planer I've ever owned and is very highly regarded by loads of professionals, so it's  well worth spending a bit of cash on if it will sort the issue out.

 

[Viljo]

So is the issue just the planer head/blade, or is it the base?

I don't know. I think it is the head, but the service thinks it is the base. I have asked them to try it with another head, let's see if they do it.

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

Cool, I didn't know something like that was available.

 

[luvmytoolz]

There is a little wiggle room on the adjustable plate due to the way the height mechanism and the inner sleeve is designed, but this shouldn't present any issues as once you press down on the planer to use it it levels out.

If it was the head shaft you'd see some wobble I would expect.

So it could possibly be the head shaft is intact but is not co-planar with the base? But Festool should be able to have detected that, and from memory of when I pulled mine apart I think that's really unlikely given the design.

Hopefully Festool find what the issue is.

 

[alltracman78]

So is the issue just the planer head/blade, or is it the base?

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

The HL850 is by far the best planer I've ever owned and is very highly regarded by loads of professionals, so it's  well worth spending a bit of cash on if it will sort the issue out.

It's cheap for a reason.
That's not really a spiral cutter.
If you look at the inserts the cutting edges are all exactly perpendicular to the axis of rotation. Basically instead of 1 big straight edge you have a bunch of little ones.
That's the cheap way out (the manufacturer).
They should be set at an angle so they cut at a true angle/spiral.

 

[luvmytoolz]

So is the issue just the planer head/blade, or is it the base?

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

The HL850 is by far the best planer I've ever owned and is very highly regarded by loads of professionals, so it's  well worth spending a bit of cash on if it will sort the issue out.

It's cheap for a reason.
That's not really a spiral cutter.
If you look at the inserts the cutting edges are all exactly perpendicular to the axis of rotation. Basically instead of 1 big straight edge you have a bunch of little ones.
That's the cheap way out (the manufacturer).
They should be set at an angle so they cut at a true angle/spiral.

I think you're confusing helical with spiral, this is most definitely a spiral cutter.

And there's nothing cheap about the performance, I use other cutters of theirs and are in the process of ordering more they're so unbelievably good. For my Jet combo they'll be making a helical for it after a mate had them make one for his Felder AD410 and they did a flawless job.

 

[alltracman78]

So is the issue just the planer head/blade, or is it the base?

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

The HL850 is by far the best planer I've ever owned and is very highly regarded by loads of professionals, so it's  well worth spending a bit of cash on if it will sort the issue out.

It's cheap for a reason.
That's not really a spiral cutter.
If you look at the inserts the cutting edges are all exactly perpendicular to the axis of rotation. Basically instead of 1 big straight edge you have a bunch of little ones.
That's the cheap way out (the manufacturer).
They should be set at an angle so they cut at a true angle/spiral.

I think you're confusing helical with spiral, this is most definitely a spiral cutter.

And there's nothing cheap about the performance, I use other cutters of theirs and are in the process of ordering more they're so unbelievably good. For my Jet combo they'll be making a helical for it after a mate had them make one for his Felder AD410 and they did a flawless job.

Yes the cutters are in a spiral shape.
But the idea of a spiral cutter is to have the cutting action slicing at an angle, not impacting straight on.
For the same reason chisels and hand planes tend to cut better when they're used at an angle.
Why do you think spiral cut router bits work better than straight cut ones?

I'm sure it works great. I have a cheap 3 inch slab flattening bit that works absolutely fantastic (though they copied an Amana design, so I guess it's a little different).
There's a reason you don't see the high end tool makers using that setup.

 

[luvmytoolz]

So is the issue just the planer head/blade, or is it the base?

If it's just the head, you can replace it with a spiral insert head for it very cheap, I did that with mine and it's absolutely sensational.

If you use insta this is a short video and pics of it in use:
https://www.instagram.com/p/Cyh_eBvL_T9/?img_index=1

The HL850 is by far the best planer I've ever owned and is very highly regarded by loads of professionals, so it's  well worth spending a bit of cash on if it will sort the issue out.

It's cheap for a reason.
That's not really a spiral cutter.
If you look at the inserts the cutting edges are all exactly perpendicular to the axis of rotation. Basically instead of 1 big straight edge you have a bunch of little ones.
That's the cheap way out (the manufacturer).
They should be set at an angle so they cut at a true angle/spiral.

I think you're confusing helical with spiral, this is most definitely a spiral cutter.

And there's nothing cheap about the performance, I use other cutters of theirs and are in the process of ordering more they're so unbelievably good. For my Jet combo they'll be making a helical for it after a mate had them make one for his Felder AD410 and they did a flawless job.

Yes the cutters are in a spiral shape.
But the idea of a spiral cutter is to have the cutting action slicing at an angle, not impacting straight on.
For the same reason chisels and hand planes tend to cut better when they're used at an angle.
Why do you think spiral cut router bits work better than straight cut ones?

I'm sure it works great. I have a cheap 3 inch slab flattening bit that works absolutely fantastic (though they copied an Amana design, so I guess it's a little different).
There's a reason you don't see the high end tool makers using that setup.

Yes, they're presented in a spiral, hence the term spiral cutter, as opposed to a helical shape, which is why it's not called a helical cutter.

Sorry but a spiral cutter is orders of magnitude better than straight knives cutters in every way, power, noise, smoothness, and quality of finish. With the spiral router cutter I use I've taken single pass cuts 15mm wide by 32m in Jarrah which is renowned for being brittle to machine and has fairly wild grain, without even a hint of tear-out!

I would challenge anyone who says they can do the same AND get the same results with a straight knife cutter!

And CSP Tooling actually supplies these and many other cutters in spiral, straight, and helical so your last point makes zero sense as they are a high end tool maker supplying to large scale industry all over the world.

 

[Viljo]

I forgot to update this earlier. Festool had the plane a bit over a month and they ended up replacing the motor housing and the front plate mechanism. Now it works as I would expect. Maybe not completely even but close enough.

 

[mino]

...
Yes, they're presented in a spiral, hence the term spiral cutter, as opposed to a helical shape, which is why it's not called a helical cutter.

Sorry but a spiral cutter is orders of magnitude better than straight knives cutters in every way, power, noise, smoothness, and quality of finish
...

I guess the point alltrackman was trying to make is that the HL 850 has a helical cutter from factory. So swapping that for a spiral (but non-helical) segmented cutter is both an upgrade (it is segmented) AND a downgrade (it is not helical).

To be fair, this is reflected in the price of the segmented head being in the same ballpark as the original Festool heads. Just a different middle-ground option priced accordingly.

This, in turn, makes what is a fabulous upgrade to a straight-knife tool into a bit of a "meh" for the HL 850.  A spherical segmented head will produce better or worse surface compared to a simple helical head depending on what material, what depth, etc. A hit/mis type result.

On the other hand, a helical segmented head is superior to both options and thus can be seen as a true upgrade.

ADD:
Just to add, the chinese friends at CSP do offer a helical head for a bit more than the straight one .. so if anyone was looking .. those $30 more are well worth it.

 

[luvmytoolz]

...
Yes, they're presented in a spiral, hence the term spiral cutter, as opposed to a helical shape, which is why it's not called a helical cutter.

Sorry but a spiral cutter is orders of magnitude better than straight knives cutters in every way, power, noise, smoothness, and quality of finish
...

I guess the point alltrackman was trying to make is that the HL 850 has a helical cutter from factory. So swapping that for a spiral (but non-helical) segmented cutter is both an upgrade (it is segmented) AND a downgrade (it is not helical).

To be fair, this is reflected in the price of the segmented head being in the same ballpark as the original Festool heads. Just a different middle-ground option priced accordingly.

This, in turn, makes what is a fabulous upgrade to a straight-knife tool into a bit of a "meh" for the HL 850.  A spherical segmented head will produce better or worse surface compared to a simple helical head depending on what material, what depth, etc. A hit/mis type result.

On the other hand, a helical segmented head is superior to both options and thus can be seen as a true upgrade.

ADD:
Just to add, the chinese friends at CSP do offer a helical head for a bit more than the straight one .. so if anyone was looking .. those $30 more are well worth it.

While a helical head is better than spiral, to what practical degree that is for a hand planer I wouldn't say, but there's no hit or miss with the spiral head over the single shear cutter originally supplied with the HL850. As ground breaking as that was when it was released, there is no comparison between them except on light cuts. The spiral produces smaller chips and cuts orders of magnitude more aggressively while doing it far easier. I can cut full depth in Oak or Jarrah with the spiral and it's much smoother than taking shallower cuts with the shear blade.

It's a helluva upgrade for very little cost.

 

[mino]

While a helical head is better than spiral, to what practical degree that is for a hand planer I wouldn't say, but there's no hit or miss with the spiral head over the single shear cutter originally supplied with the HL850. As ground breaking as that was when it was released, there is no comparison between them except on light cuts. The spiral produces smaller chips and cuts orders of magnitude more aggressively while doing it far easier. I can cut full depth in Oak or Jarrah with the spiral and it's much smoother than taking shallower cuts with the shear blade.

It's a helluva upgrade for very little cost.

Not disputing any of that is true for you. However, all your points are about the advantages of a segmented head - it just does not bog down with a design like the HL 850 that has power aplenty on the motor side.

In theory and also my experience, the advantages of a helical cutter are in the smoothness of the resulting surface and ability to get a clean cut even when going against grain etc. Now, remembering the absolutely horrible state your cutters were in (the original thread), I have no doubts it is now incomparably better *for you*.

I also agree that for a hand planer taks many people do not care about the smoothness of the surface. I mean, I cannot imagine using the cutters in the state yours were. So definitely different use cases, hence my points it depends on what one uses the planer for.

When I had the HL 850 borrowed, (with new cutters) I would get absolutely smooth surface even around knots in softwood. I could not achieve that with my Narex that has straight cutters. Had nothing to do with power, both have aplenty of it, and all to do with straight versus helical cutters.

---
Now thinking how good the segmented helical head will be at such a small diameter. Would be great if someone can do a 3-way comparison of the Festool head with fresh blades and both the CSP segmented head options. Getting the cutters aligned on a helical head is no joke. I can imagine them producing a dented surface if not perfect - compared to a straight version.

/end OT

 

[Coen]

While a helical head is better than spiral, to what practical degree that is for a hand planer I wouldn't say, but there's no hit or miss with the spiral head over the single shear cutter originally supplied with the HL850.

Do you know when they switched the cutter on the HL 850?

My brother got one recently and I was surprised it had a spiral cutter. I thought it had a straight cutter (it was one of the reasons I didn't buy a HL 850 when I bought my EHL 65).

 

[luvmytoolz]

While a helical head is better than spiral, to what practical degree that is for a hand planer I wouldn't say, but there's no hit or miss with the spiral head over the single shear cutter originally supplied with the HL850.

Do you know when they switched the cutter on the HL 850?

My brother got one recently and I was surprised it had a spiral cutter. I thought it had a straight cutter (it was one of the reasons I didn't buy a HL 850 when I bought my EHL 65).

I got mine when it was first released in Aust which I think was roughly around 1984-1985 from memory,and it came with the shear cutter then by default. I didn't know it shipped any other way as that was the huge marketing and selling point at the time.