CT36 Top Cover Failure

[agrimson]

The top plastic black cover of my CT36 extractor had a catastrophic failure.  I was moving the unit and the plastic just snapped apart.  This appears to be a brittle material failure and I think the plastic is ABS per the molded lettering on the inside of the part.  It is about ten years old and it has never been exposed to any chemicals or solvents as I know that can cause brittleness in ABS.

Has anyone ever seen anything like this?  The unit is still working fine and I am curious about it as I spent much of my career in the plastics industry and worked a lot with ABS.

 

[peter halle]

Welcome to the forum.  Sorry to read about your situation.  Yes, we have read here about extractor top failures.  You might be able to get the replacement top from Festool thru their ekat (spare parts) catalog if you have your extractor model number.

Peter

 

[onocoffee]

I've been trolling the used market quite a lot lately and it seems that this is not terribly unusual - basing this on the number of older CT22 I see online missing their hose garage or in other states of plastic disrepair. Sometimes, you even see replacement hose garages for sale online. But Peter's advice to reach out to Festool is the simplest option.

 

[cpw]

My CT26 had a similar problem.  It wasn't catastrophic, but pieces kept chipping off creating sharp edges.  In my case, I the EKAT part for a newer CT26 has the T-Loc instead of the old style latches so it was an upgrade.  US Tool and Fastener sells the hose garage drop shipped, which can save on shipping.

I also needed to replace my socket from EKAT directly, because the contacts have worn.

 

[Cheese]

When you moved it, did you by chance grab it by the front of the cover/hood?

That's how I broke the hood on my MIDI. I learned my lesson to only move it by using the handle or the Systainer on top of the hood.

Unfortunately, it's a $76 lesson.  [blink]

 

[RJNeal]

On a another note…
The painter showed up last week with his 26 that rolled out the back of his pickup on the way to the job site and down the bank a bit.
I imagine not much of a hose garage left.
It was pretty much intact with only scars on one corner.
Go figure

Rick

 

[Packard]

A google search “what can make ABS to become brittle” gets many mentions.  Most seem to be complaints from 3D printers.

But universally, exposure to UV can be a culprit, as is extreme cold.

Also noted was ABS is known for its mechanical properties; its chemical resistance is not particularly good.

 

[Crazyraceguy]

I'm pretty sure that those kinds of parts are available on the EKat system. Maybe not for the CT22, because of its age.
I have also heard that some have up-sized the tub on their machines too. If they had damage to the original tub of say a CT26, they might get a replacement for a CT36.
I think I remember reading that you can install an actual hose garage in the smaller units like the CT15 or CT25, replacing the flat-top original? (the one from a Midi?)

 

[Holzhacker]

Over the years the hose garage on my CT22 broken repeatedly. First time or two I was able to buy a new one. After that I started repairing it with fiberglass and mesh tape. Worked really well until it broken at other spots.
Now I have a sys 1 mounted on top of the ct22 with the bottom cut out. This acts like the hose garage sort of. Not big enough for the house but big enough for nozzles and sandpaper. I guess I could cut the bottom out of sys 2 for more room but haven't wanted to do that.
Probably would have been better if Festool had made the tops / hose garages thicker, more heavy duty given they abuse they get.

 

[cpw]

When you moved it, did you by chance grab it by the front of the cover/hood?

That's how I broke the hood on my MIDI. I learned my lesson to only move it by using the handle or the Systainer on top of the hood.

Unfortunately, it's a $76 lesson.  [blink]

The first breakage was not in front or grabbing it from front.  I think I was maybe a little rough with setting the wand or a tool down on it.

The breakage that got me to rplace it was in the front, I did grab it and had a bit flake off.  The next time more of it flaked off and the bits of plastic are sharp enough to cut you; which is why I spent the $76 to actually replace it.

The vac is expensive, at $607.50 when I bought it in 2016; but it has been in service for 8 years now.  If it was another brand, I'm not sure if I could have spent the ~$200 in repair parts over those years (cord, the hose garage, socket) to keep it running in proper condition.

 

[Packard]

I know that metal will fatigue.  Most of us do.  Did you ever take a wire coat hanger and bend it back and forth until it cracks.  That is one form of fatigue. The bending also created heat and the metal gets harder just before cracking. 

So I was wondering if ABS does too.  Apparently it does and it also apparently is affected by the environments temperature (both high temperatures and low temperatures have an impact).

I am not enough of an engineer to understand what the nature of the fatigue source was.  Was it high cyclic rate vibrations, low rate, large displacement, etc. 

I would assume that there are some vibrations in this application (I don’t have this equipment).  So perhaps ABS was a poorly chosen material.  Maybe fiberglass reinforced nylon would be a better choice.  In general, I think of ABS as a relatively tough resin.

I would be disappointed, given the number of failures, if Festool didn’t make some design or specifications changes.  Manufacturers are often reluctant to redesign a product to solve a problem out of fear that they would have to offer free corrections to people who already have the affected items.

At the least, I would like to see Festool explain the premature failures.

Here is the scholarly research that was beyond my ability to concentrate.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6213121/#

 

[Duckler]

This happened with my CT26 extractor.
IMO the people at Festool abuse the clientele by making us pay obscene prices for replacement parts.
One of my newer hobbies is getting along with more reasonably priced tools. Festool has become too much of a foo-foo boutique brand for me.

 

[Packard]

I’ll ask my brother-in-law about this tomorrow.

He was a strength of materials engineer (resins) for Union Carbide before he retired.

I don’t know if we have enough data for him to make a judgment, but he has the education and background to do so.

 

[onocoffee]

I think I remember reading that you can install an actual hose garage in the smaller units like the CT15 or CT25, replacing the flat-top original? (the one from a Midi?)

It stands to reason since whenever I see the CT15 at the dealer, it looks almost exactly the same, but with a hose garage, bluetooth and brake. Even the bag for my CT MIDI is the same as the CT15: 204308

Maybe one day, when my MIDI is old and cracking, I can replace the tub with one from the CT25. Hmmm, I wonder how much that would cost now...

 

[peter halle]

I know that there were a ton of complaints on the CT22 / 33 era models.  Then when the 26/36 came out there were still complaints.  I think that once Seth and I were at Festool they showed us a redesigned top that was re-enforced.  But I think that it might have been 2017.

Peter

 

[Cheese]

I know that there were a ton of complaints on the CT22 / 33 era models.  Then when the 26/36 came out there were still complaints. 

My CT 22 still performs wonderfully after using it for 17 years, I don't think it will outlast my Milwaukee 8925 but that was purchased 30 years ago and is made from stainless rather than plastic.  [smile]  That could make a difference.

The hose garages on all of the Festool vacs are susceptible to cracking if you just grab the hose garage itself and attempt to move the vac. I'm guessing the typical wall thickness of the hose garage is around .060" or about 1.5mm. That's not a lot of material to withstand the grab & jerk gesture when you want to quickly move the vac.

I cannot state this strongly enough...if you need to move the vac, use the interior handle on the vac or if you stack Systainers on the hose garage, then use the Systainer itself to move the vac.

 

[leakyroof]

I know that there were a ton of complaints on the CT22 / 33 era models.  Then when the 26/36 came out there were still complaints.  I think that once Seth and I were at Festool they showed us a redesigned top that was re-enforced.  But I think that it might have been 2017.

Peter

  My CT 33 Auto Vac broke on me, shattered really, and the replacement part does seem to be sturdier than the original top cover. It's the only Vac that I've lost the Top Cover on. My old CT-22 never broke, and my current CT-26 which I replaced the 22 with hasn't either.

 

[Michael Kellough]

I know that there were a ton of complaints on the CT22 / 33 era models.  Then when the 26/36 came out there were still complaints. 

My CT 22 still performs wonderfully after using it for 17 years, I don't think it will outlast my Milwaukee 8925 but that was purchased 30 years ago and is made from stainless rather than plastic.  [smile]  That could make a difference.

The hose garages on all of the Festool vacs are susceptible to cracking if you just grab the hose garage itself and attempt to move the vac. I'm guessing the typical wall thickness of the hose garage is around .060" or about 1.5mm. That's not a lot of material to withstand the grab & jerk gesture when you want to quickly move the vac.

I cannot state this strongly enough...if you need to move the vac, use the interior handle on the vac or if you stack Systainers on the hose garage, then use the Systainer itself to move the vac.

I broke the hose garage on my CT22 about a week ago. Tried to pick it up by the HG and pulled the HG right off with a lot of potato chip crunching sounds.

I ordered some black ABS sheets 1mm thick and some black abs solvent adhesive to see if I can fix/re-engineer the HG.

 

[Packard]

I sent a note to my brother-in-law this morning.  He was a strength of materials engineer for resins until he retired from Union Carbide.

His specialty was films (like what they use for plastic bags).

Hopefully he can shed some light on what could be making the ABS brittle.

I will report once he replies.

 

[Cheese]

I broke the hose garage on my CT22 about a week ago. Tried to pick it up by the HG and pulled the HG right off with a lot of potato chip crunching sounds.

I ordered some black ABS sheets 1mm thick and some black abs solvent adhesive to see if I can fix/re-engineer the HG.

Good luck on the repair Michael... [smile] As a last ditch effort you may also be able to reinforce the housing with some fiberglass mat and some epoxy.

As an aside, Festool still offers the "hood" for the CT 22 at $166.40  [huh]  but they no longer offer the hose garage. [mad] [mad]