Kapex frustration

[GPowers]

Trying to make a flag case for my mother to hold my deceased father flag. 

I'am using the Kapex to make 45 degree bevel cuts. BUT i'am not getting a square cut when the saw is placed at a 45 degree bevel (see the first photo with pencil). But when I move the saw to 90 degrees I get a nice square cut see second photo (with out pencil).

The last photo shows the position of the Kapex for the 45 degree bevel cut.  Plus the material is being held in place with a clamp to the base the the cut is being made. The cut is being made the same for the 90 and beveled cut. The saw is pulled out then pushed down and back toward the fence.

What am i doing wrong??

Glad I was experimenting with inexpensive pine on a prototype before using the black walnut.

 

[nclemmons]

Potentially the weight of the saw motor is deflecting when you tilt to the side.  Is the piece too wide to cut in an upright position at a 45 angle??

I have seen others that have had this error on the FOG.

Might try tilting to the other side to see if it occurs there as well.  That would suggest it is weight deflection rather than an alignment issue.

Neil

 

[GPowers]

Potentially the weight of the saw motor is deflecting when you tilt to the side.  Is the piece too wide to cut in an upright position at a 45 angle??

My thought is that the bevel cut would be more accurate then a miter cut. The piece is only 3 1/2"  high so it could be cut as a miter.

 

[Harvey]

I think the original thread was this one:
http://festoolownersgroup.com/festool-tool-problems/kapex-120-inaccuracy-with-bevel-cuts/

 

[wrightwoodwork]

You should be able to cut out the flat out of curiosity is piece you are trying to cut perfectly flat. Quite often a piece of wood will be capped and can cause the mitre to be off the square especially if it it is placed with the cap down so the timber ever so slightly rocks causing the cut to go off the square even though at 90 the saw cuts square. If the timber is capped the cap should face up so the the timber does not rock pine at times can be bad for being capped, you want to try fitting 225mm facia boards with a scarf joint and they are both capped different directions you need to use a block plane to fine adjust the mitres to make the fit

 

[Jonhilgen]

Dull blade?

 

[GPowers]

Might try tilting to the other side to see if it occurs there as well.  That would suggest it is weight deflection rather than an alignment issue.

Neil

The error is less when the bevel is cut on the right. The gap is about the size of a business card over 1/3 of the width.

When cut as a miter, there is still a gap see bottom photo

 

[peter halle]

Greg,

I have had the exact same thing and said things under my breath.  In my case it was a filthy and dull blade.

Just giving some insight.

Peter

 

[Kev]

I'm interested in knowing how much downward pressure you're applying. I've made cuts like this with no noticeable error, so there's certainly a problem - either the saw or the technique.

A point that may be interesting, I cut with my left hand - so on the same cut I'm possibly lifting a little instead, not potentially compressing (obviously the error could be exaggerated further down the slides).

 

[Kev]

Just another thought - have you sighted this with the laser? I'd be interested to know it the laser line is true before the saw head is touched.

 

[GPowers]

Greg,

I have had the exact same thing and said things under my breath.  In my case it was a filthy and dull blade.

Just giving some insight.

Peter

Would this be considered filthy? I'm just a Diy'er so the blade does not get used that often.  Only cut Maple, Oak and pine

 

[greg mann]

Greg,

If the guide tubes are not parallel to the table you will get the situation as described. This condition would not show up at 90 degrees but would on a bevel. Can you make the cuts as miters? If not, it should be less evident if you don't use the slider function but would still show up to some degree. I hesitate to suggest this is the problem because it might be difficult to measure. I will take a look at my saw to see if there is a good way to determine this parallelism.

 

[Gregory Paolini]

That blade, while probobly due for cleaning, doesn't look too bad.

In my experience, 99% of out of square issues which occur during bevel cuts, are operator induced.

We have a tendency to muscle the saw during a bevel, rather than guiding it.  And instead of pulling the saw down in a angled vector, we still pull straight down, at 0/90' forcing the saw out of desired square

Right bevel, right hand sawyers tend to push too hard at the beginning of a cut, and as the saw travels in, and has more rigidity, the error subsides

Try concentrating on the angles the saw is moving, and follow those like a robot

Let me know if that helps at all

 

[GhostFist]

Just a thought but is it possible the piece you're trying to cut is moving during your cut? Is it possible to plunge the saw beyond the workpiece and push it into the wood?

 

[stevep]

Are you clamping the pine down before you push the blade through? If it is not clamped, the blade will move the wood as it goes through when doing a mitre cut. It happens on bandsaws as well.

 

[zapdafish]

Greg,

I have had the exact same thing and said things under my breath.  In my case it was a filthy and dull blade.

Just giving some insight.

Peter

Would this be considered filthy? I'm just a Diy'er so the blade does not get used that often.  Only cut Maple, Oak and pine

It wouldn't actually be the wide flat area that gets dirty but the sides of the teeth. I can see a brown build up on the sides of your teeth. I've cut 2x4's and it doesn't take much for pine to gunk up blades and router bits.

 

[GPowers]

Not much time overt he holidays to work on this.

I did get time to clean the blade. Cleaning did make a difference.  Plus as Gregory Paolini said I relaxed and tried not to force the cut. Results were better but not perfect. I will be working on this project more this week, and will see what happens.

I have also been talking to Festool Customer service.

Thanks everyone for you help. 

 

[fshanno]

Greg,

If the guide tubes are not parallel to the table you will get the situation as described. This condition would not show up at 90 degrees but would on a bevel. Can you make the cuts as miters? If not, it should be less evident if you don't use the slider function but would still show up to some degree. I hesitate to suggest this is the problem because it might be difficult to measure. I will take a look at my saw to see if there is a good way to determine this parallelism.

Difficult to measure and impossible to fix.  That is really scary.  I'm going to check mine right now.  I don't think it's happening but man, that's spooky.

 

[fshanno]

Greg,

If the guide tubes are not parallel to the table you will get the situation as described. This condition would not show up at 90 degrees but would on a bevel. Can you make the cuts as miters? If not, it should be less evident if you don't use the slider function but would still show up to some degree. I hesitate to suggest this is the problem because it might be difficult to measure. I will take a look at my saw to see if there is a good way to determine this parallelism.

Difficult to measure and impossible to fix.  That is really scary.  I'm going to check mine right now.  I don't think it's happening but man, that's spooky.

It's not happening on mine.