MFT welds failing

[cfullen]

Has anyone had these welds just break?  I seem to have noticed it just a week ago or so and then yesterday the first weld just came apart.

To be clear, I’m referring to the cross member that connects each set of legs. 

 

[ear3]

That's not good.  I've never seen a complaint about this since my time on the FOG.

How long have you had your MFT, and what's your usage like (lots of setting up/striking/moving, or do you tend to keep it set up for long durations)?

 

[cfullen]

I have it in my shop most of the time.  Either set up, or put away in a corner.  20% of the time it comes with me to the job site. 

I’ve had it for about 3 years now.

 

[Peter_C]

Good excuse to buy a welder?

 

[McNally Family]

Is that steel or aluminum?

 

[tjbnwi]

Looks like the metal failed not the weld. Rust issue?

Tom

 

[grobkuschelig]

That should be steel, I think.

 

[peter halle]

I agree with Tom that it does not appear to be a weld issue.  If you look at the the outside of rim of the break there are rust stains.

That being said I have one of the ugliesr MFT's out there.  Mine has sat in the driveway with the top covered by rubber roofing membrane and the legs have been used as fire hydrant substitutes by the neighborhood dogs.  But my joints haven't failed.

Your local situation and weather are different than mine.  As a moderator I can get a general idea of where you live.  Was your shop flooded?  Any other environmental issues that you might think be part of the problem?

Peter

 

[ArtisanWoodworksAndDesign]

That little bit of rust showing in the picture doesn't look like it had anything to do with the failure and probably happened as the weld was breaking.  It looks like it was improperly welded and almost blew through the thin metal leg during the process, but was hidden until stress took it's toll.  I'd push them to send you a new leg or legs no matter what the warranty state is.  If you were rough on that, the weld should have been strong enough that the tubing would have bent first as an indicator.  Just my 5 cents worth.

 

[Bohdan]

Looks like a fatigue failure possibly caused by flexing the joint each time that you folded up the MFT legs.

Still shouldn't have happened as the legs are designed to be folded up.

 

[TinyShop]

[member=11438]cfullen[/member] - not sure if you know., but if you're in the U.S. or Canada the MFT/3 is covered by the standard 3-year warranty (it's an exception to the "must have a cord" requirement).

 

[peter halle]

[member=64030]TinyShop[/member] beat me to a follow up post.  I would contact Festool on Monday and take to them.  That is an issue that I don't remember being mentioned here (if might have been and I am not perfect obviously).  Whether or not it would be under warranty they might be interested to get your legs back for examination.  More MFT's are sold here than in any other country.

Peter

 

[cfullen]

I do live in the gulf south region. But no, my shop has never flooded.  I don’t think this is a rust issue.  Guess I could be wrong.  The other welds are showing the same signs of failure.  I will take some pics of them tomorrow.

I’m going to try to contact festool and see what they have to say. 

 

[junk731]

Could be just the lighting but looks like it had a pretty good impact just above the weld. If the tube is deformed at all, that's your answer. The weld didn't fail the 2 were ripped apart.

 

[Rip Van Winkle]

Judging by the photo, I would say that is a weld issue. While weld metal is supposed to be as strong or stronger than the metal being welded, the heat of welding can effect the molecular structure of the material being welded, causing weak areas around the weld. There are ways to reduce this problem, but even carefull welds done under strict protocols can have issues, and I doubt Festool is ussing the same procedures as would be used on a commercial jet plane or nuclear facility. If you look at were the joint broke, it’s right by the welded material. Since it’s steel I presume any decent bike shop could weld it back, or possibly a garage, machine shop, school shop, etc. It might be cheaper just to buy a new leg though, if the part is no longer under warranty.

 

[Tom the Remodeler]

The welds failed on one of my MFT/3 tables, but only after many years of use outdoors in the snow and rain. There must have been some pin holes in the paint and the joint eventually rusted and failed when I removed the legs to permanently mount the table on a rolling cart.

In my mind, the legs are a consumable, something to be replaced after many years of service.

 

[Gregor]

I’ve had it for about 3 years now.

Call Service, describe problem and ask (if >3 years: nicely) for replacement.
This shouldn't happen that early in the life of an MFT/3.

 

[BJM9818]

Could be just the lighting but looks like it had a pretty good impact just above the weld. If the tube is deformed at all, that's your answer. The weld didn't fail the 2 were ripped apart.

X2 unless it’s just the pic it looks like a decent Impact above the cross member probably followed by the object hitting the cross member.

 

[cfullen]

Here are pictures of the other welds.

 

[cfullen]

All 4 welds are showing some signs of failure.