why do guide rails warp?

[dklent16]

[attachimg=2]Why do track rails warp?

 

[Gregor]

Most likely for the same reason why with your ruler tape looks damaged around the 2.75" mark:
Application of excessive exterior force.

 

[Naildrivingman]

Most likely for the same reason why with your ruler tape looks damaged around the 2.75" mark:
Application of excessive exterior force.

That damage would take an excessive amount of force. I can’t comprehend how that’s user error...on the other hand, most of my tape measures ultimately suffer a similar fate.

 

[Gregor]

That damage would take an excessive amount of force.

I have no clue how it could happen without that.

Most likely it's a storage problem, like that it was squeezed into some area that dosn't have the needed dimensions to accept the rail in the original geometry or put somewhere where it wasn't fully supported and something was put against/onto it.

Aluminium isn't that hard to deform and the flat part (without the T-slots) isn't that thick and the center of the bend seems to be located right to the center of the rail (in the flat part).

Answers to questions like
- is that bend even over the whole length or only on the end?
- how is this normally stored and, in case it's not a shop-only rail, moved?
- what 'could have delivered excessive force' encounters did this rail have?
might help for further speculation on how this could have happened to it.

 

[DaveCH]

I experienced the same problem with my 1080 rail that came with the MFT.  Mine was cupped to a similar degree, but upwards at the edges, rather than high in the middle.  Mine had a very consistent radius of cupping along the full length of the rail.  I use the MFT only in my workshop and store the rail carefully, so it certainly wasn't a case of force or impact.

Given the uniformity of the cupping along the length of the rail, I can't see how any normal usage scenario could generate this kind of deformation.  Wonder if there's an occasional issue with some kind of internal stress remaining in the rail after manufacture.

BTW My dealer was great and replaced the rail free of charge.

 

[Roseland]

I suspect it is stresses from manufacture relieving themselves.

Andrew

 

[Administrator_JSVN]

Thanks for sharing this. How long have you had the rail? How and where do you usually store the rail?

(Tyler)

 

[ear3]

[member=101]Festool USA[/member] I tried to PM this, but it looks like direct messages to you are blocked?

Tyler,

I thought I'd reach out to you about a similar problem I have with my 2700 holey rail.

The rail is bowed along it's length.  Although I can still get away with using it to set the LR32 for shelf pins, it is basically unusable to me now for precision cuts.

The thing is, this is the least used rail out of all the rails I own (which is all of them up to 3000mm in length).  It never leaves my shop, and is stored in the same case where I store my 3000mm rail, so I don't know why or how it would have been subjected to stresses that didn't also affect the longer rail.  I wish I could tell you when the problem developed, but the truth is, I never thought to check it for bowing when I first got it a few years ago from the ToolNut, and since I use it so infrequently with the tracksaw, I don't know whether the problem was there from the beginning or whether it is something that developed later.    

For reference purposes, I documented the problem last year when writing about my hybrid workbench build.  It's the 7th picture down in this post:
http://festoolownersgroup.com/works...s/hybrid-workbench-build/msg488657/#msg488657

Do you think there might be remedies for this issue?

Thanks for sharing this. How long have you had the rail? How and where do you usually store the rail?

(Tyler)

 

[android]

I did a little reading on Al extrusions. They can warp because of rapid cooling after the extruding process. It seems to be more severe with water quenching vs. glycol quenching. But... It is seems to be immediate and shouldn't pass QA. I didn't see anything that would hold stress and then warp later. That's kind of uncharacteristic for Al since it is so soft and these rails don't even appear to be heat treated. Usually marketing hype would include "T6 hardened for long life" or some such benefit. My rails look like they are just anodized an are very soft.

 

[Administrator_JSVN]

I asked around about this, and it's apparently pretty rare for this to happen. Obviously, it could warp from misuse or storing them in weird/extreme ways. (I'm not implying that happened in this case. Just saying that it can.) It's clearly an older rail. (The black splinter guard suggests that it's from 2012 or earlier.)

While I can't give a good answer as to why this rail bent, it does appear to happen pretty rarely. If any of you experience something similar, let us know.

(Tyler)

 

[Oldwood]

Hi Tyler.

"it could warp from misuse or storing them in weird/extreme ways"

Could you describe some of those so we can avoid them?

Thanks,
Gerry

 

[Administrator_JSVN]

Hi Tyler.

"it could warp from misuse or storing them in weird/extreme ways"

Could you describe some of those so we can avoid them?

Thanks,
Gerry

I'm mostly thinking of pretty extreme, careless things like storing them underneath other objects, storing them in tight spaces/positions that would bend the rail, etc. Mostly common sense stuff.

(Tyler)

 

[Distinctive Interiors]

I have a 3000mm rail that I store flat in the original case that the rail shipped to me in. When it arrived, the case was a bit beaten up, so I stripped it all apart, removed all the nails and staples that held the cardboard to the softwood timber stretchers and then glued & stapled it all back together again. That was 4 years ago and my 3000mm rail is still as straight as I can discern.

I use it a lot for straight cutting and routing large sheets of Corian for fabrication as well as breaking down full sheets of material.

 

[Stone Message]

There is something odd about the perspective in that picture.

Why has the OP not given more information about the guide rail, how it has been used and how it was stored ?

I would like to know if the picture has been edited with Photoshop - not that I doubt the honesty of the OP but it would explain why the image seems odd. Perhaps an image taken from a 45 degree angle (ie move the camera to the left or right and take another shot) would solve that issue.

Peter

..edited a few minutes later

I just looked up the OP. He posted this, hung around for a couple of hours and has not signed back in again ! Perhaps he is not really interested in an answer.

The picture was taken at 15.54 hours on 23rd October 2017 using a Samsung SM-J327P mobile phone. No flash was used.

 

[Coen]

Most likely for the same reason why with your ruler tape looks damaged around the 2.75" mark:
Application of excessive exterior force.

That damage would take an excessive amount of force.

No it doesn't. Look at the profile of the rail... it's just a few mm of alu. Any adult can bent and break that with their bare hands. Bending around the centerline of the rail (or any line parallel to that) is very easy. The notches only provide resistance to bending in the other two directions of bending.

Now what comes to mind is picking up a long rail (or coupled one) on that one edge.

 

[Stone Message]

Where has the OP been ?

That rail should look like this...

[attachimg=1]

Peter

 

[Svar]

Where has the OP been ?
That rail should look like this...
Peter

First, why does it matter were the OP has been? Second, arbitrarily manipulating the original picture is not a good way to prove your point.
Regardless, you can clearly see that the saw does not sit flat on the rail and the gap under the shoe is considerable.