Heat Checking in Kapex Saw Casting

[ajones]

Since when is it wrong for someone - especially a new member - to come here and express a concern?  It happens several times a day.  Whether it has been a label that doesn't stick, a peeling splinter guard, a pad that doesn't rotate, a paint or metal coating that chips, etc., we read about it and 99.97 percent of the time the members here try to help out with answers or avenues for help.

What was so different in this case?  He bought a Kapex, he noticed something he was concerned about and he took it back.  He looked at others at the dealer, noticed the same thing and decided to pass.  Then he researched, found the FOG, came and asked questions.  Then he frankly got treated basically like an idiot by numerous members for examining his saw and having concerns and asking us about it.  That isn't the way we normally do it here.  If you re-read the opening post he admits that this was his first Festool and asked that we not be hard on him.  What may not be important to you might just be the most important thing at that time to someone else and how you say something can be as important as what you say.

Peter

it is good to see that the way new members that post with issues or concerns are being met with a more positive attitude than in the not to distant past

 

[Alan m]

i have to agree with the OP about the cracks.
any cracks in any tool is bad. especially one as expensive and high quality as a festool.
maybe vibrations or knocking it around will loosen the casting and some day it will disintegrate as he is cuttting. possably causing all kinds of damage to himself and his tool.
if i found any cracks in any of my tools id return it.
cracks are a sign of movement and the bed could be distorted enough to though off the cuts.
im fairly positive that the cracks wouldnt be a problem but you never know.
if you bought a jumper etc and there were a few little cuts in the material on the inside, you know that if you baby the jumper it will be ok but deep down you know that some day something unexpected will happen and it will get bigger and bigger untill its ruined.
would you keep that jumper when you payed money for a new one in perfect condition.

welcome to the fog and festool

find anouther dealer and check theirs

 

[WarnerConstCo.]

Ok, but are they really cracks in the alloy casting (which is not 100% aluminum)?

 

[Dan C]

Ok, but are they really cracks in the alloy casting (which is not 100% aluminum)?

I must say, any crack in metal that you can see is the manifestation of cracks you could not see.  Regardless of the type of metal it is cast in, I know that I would not buy it.  Would you buy a car that had a crack in the cast wheel?  I doubt it. 

If you own a Kapex and don't care to look, then don't.  If you do, then do.  Don't blow up at a guy for asking a question.

And I must agree with Peter- Had I been treated as the OP for asking a simple question- and gotten railroaded for asking if the problem had been see before, i would have been gone in a hurry.

 

[Kev]

At the risk on being stupid - Isn't "heating checking" something that affects material through cycles of temperature increase and decrease? Causing cracking over time?

I'm not saying the bases examined don't have cracks of any sort - but I suppose I'm questioning my understanding and the probable cause.

The KAPEX base is a cast alloy and these cracks appear "out of the box".

Is there a particular spot on the castings that the cracks appear or are they just all over the place? From a fairly close inspection I can't see anything that would concern me with my KAPEX - but if there's a specific spot to check I'm happy to look.

If the saws you're looking at are a bad batch or have imperfections inconsistent with others, Festool should be made aware and should offer comments on the issue.

Kev.

 

[Dion Marriott]

Well I have been well and truly put right!

Thank you to all the people who responded.

I really didn't intend my question to taken as alarmist; really just to see if this is a common "feature" and whether I should be concerned. The answers are "no" and 'no"/"NO!"/"maybe".

A bit of background  - I work in the railway industry, and I am a bit hypersenstive to casting issues, for obvious reasons. It has become a habit to check components before operation.

Kev is right, heat checking is incorrect terminolgy - more like hot tears. They definitely appear to be in the alloy, not the finish. The ones I noted were in the right hand side of the diamond cut-out, and in some corners of some of ribbing underneath.

Anyway, I shall defer the Kapex until I have checked with other suppliers. In the meantime, I'll get onto other jobs.

Cheers, Dion.

 

[TomGadwa1]

Ahem, that is a MAGNESIUM alloy casting that we are "concerned" about. I decided to further investigate my KAPEX and used a 300 watt halogen lamp to look for these cracks. I found many cracks on the underside of the casting. As far as affecting the cutting accuracy of the saw goes it does not seem to have an adverse result. As some other posts have said the frequency and amplitude caused by the motor and cutting action of the saw do not seem to be a problem. If this was a Space Shuttle booster rocket or a nuclear power plant piping then non-destructive testing would be in order for the safety of the public which I have been involved in. That said I do not believe that there is a safety or performance issue to worry about.

 

[agehall]

If this was a Space Shuttle booster rocket or a nuclear power plant piping then non-destructive testing would be in order for the safety of the public which I have been involved in. That said I do not believe that there is a safety or performance issue to worry about.

Are you saying you DIDN'T get a booster rocket in the box and a nuclear power plant in the motor housing?  [eek] I suggest you return yours immediately!  [big grin]

On a more serious note; I don't blame the OP for asking. If you were to look at any of the tools I bought new, you probably couldn't tell they have been used at all. If I saw cracks on a new tool (especially as expensive as the Kapex), I too would worry a bit and probably try to exchange it for a specimen that doesn't exhibit the problem. If I was a professional user, using the tools on various jobsites all the time, I probably wouldn't worry but rather rely on the Festool service department in case anything happend.

 

[semenza]

Hi Dion,

Welcome to the FOG !  [smile]

Thanks for posting. You have brought to light a potential issue that people might never be aware of without looking under the saw.

Seth

 

[johnnyinnb]

Checked mine this morning real quick, found one spot about 1/8 th" or so, not to worried but will keep an eye on it.

 

[hockey_magnet]

Haven't checked mine yet. You would think these castings would be pretty carefully checked by Festool and if it was felt to be an issue, they would not let them go on the market. I'd be interested if Shane had a comment on this issue

chris

 

[Administrator_JSVN]

Chris,

I'll respond but I don't have a lot to offer. I have no expertise in metallurgy or engineering. I have no knowledge of any similar reports over the past 5 years that we've sold the Kapex in US/Canada.

I respect any customer's right to a product that meets their expectations and I strongly believe that's a commitment that Festool shares. I have forwarded this information along to Festool Australia and Germany so that they are aware of it. I have little doubt that it will be fully investigated based on Festool's stringent requirements for its parts suppliers.

I'll confirm that the base is made of a magnesium alloy.

Shane

 

[hockey_magnet]

Chris,

I'll respond but I don't have a lot to offer. I have no expertise in metallurgy or engineering. I have no knowledge of any similar reports over the past 5 years that we've sold the Kapex in US/Canada.

I respect any customer's right to a product that meets their expectations and I strongly believe that's a commitment that Festool shares. I have forwarded this information along to Festool Australia and Germany so that they are aware of it. I have little doubt that it will be fully investigated based on Festool's stringent requirements for its parts suppliers.

I'll confirm that the base is made of a magnesium alloy.

Shane

Thanks Shane. Certainly I couldn't expect anything more at this point. As I said, I'd be surprised if Festool came back and said they were unaware of this and it was a real issue. I'm certainly no expert on casting and metallurgy but I'm pretty certain that there is a way of checking castings of this type for flaws as they come through the process. So I would tend to think the bases are considered to meet specs. Just an opinion