Improving T4x chassis design (anti-flex)

[Jiro]

When I get my TP back, I am going to mod the inside of the case so it does not flex, thus preventing any further damages flexing can cause the system board... I am quite annoyed with the fact I had gone through 2 motherboard replacements in less than 2 weeks with normal use of the thinkpad!!!

This idea is still premature, and may not be possible because of the limited space inside the thinkpad to mount in some sort of "roll-cage" inside the case, So im really open to some suggestions right now!

[christopher_wolf]

Look at the design of the roll-cage of the T60, then get out a drafting board, drawing implements, chair and light...Then get to engineering it.

After looking the chassis over and estimating the feasibility of the project; do the following in a loop

1.) Decide what material you want it made out of; if price is no object, get the sturdiest and, possibly, the lightest you can find...To budget, take a good look over the spec sheets from materials manufacturers; figure out how much warping/changing of the material will be induce by working it, get to see if you can easily make it in a machine shop and/or get them to make it for you.

2.) Decide where you want to anchor it; what other stresses this will introduce; how much weight will it add; so forth.

3.) Come up with a Plan B (e.g. " roll cage is not feasible, build roll/torsion bars." etc)

4.) Look over it, take some breaks, come back and look over the design again and nit pick some more; criticize the hell out of it (especially what it is going to do to the airflow, how easy will field maintenance be, etc.)

5.) Build a model with an old T4X Thinkpad Chassis and model planar. and toy with it; keep it on the bench, next to your bed when you sleep and stare at it when you are eating breakfast in the morning (this part isn't all *that* necessary but it puts the mind at ease ). Bend and try to warp that model and estimate where the stress points. It would be good to have FEA and CAD programs available at this point.

I would think the roll bar/torsion bar is the best bet as there isn't enough room for a full plate and cage structure that could be squeezed in.

In any case, this is a pretty big mod; good luck

[Jiro]

In the mean time, I think I will use a ThinkPad Port Replicator II as it may add to the stiffness...

[draco2527]

Answer to original post

+

In the mean time, I think I will use a ThinkPad Port Replicator II as it may add to the stiffness...

=

LOL!!!!!

[cmarti]

Is his going to carry the laptop with the port replicator attached?

[mdarnton]

I don't quite understand what you're doing to have this problem that none of the rest of us do, but nevermind. What about armoring the exterior underneath with something like graphite/epoxy board? Or even 1/8" sheet aluminum. It doesn't seem like you'd have to do something too exotic to stiffen things up quite a bit.

[K. Eng]

I'm not sure that chasis flex on the T4x is responsible for system board failures.

I'd like to do a study on T4x failures, but it seems like the T40s have higher incidence of failure than the 41/42 and 43 models. Since they all share the same chasis, I'm not sure the chasis is the problem.

[JohnV]

Hey guys I work for a school that has a contract with IBM for our computers. We have had a number of laptop motherboard failures. Here is some info that came up recently from a meeting regarding the Lenovo laptops. I am not sure which models this is reffering to, though we are still running the T43's.

***Lenovo is putting yet additional reinforcement into the laptop cases (a titanium cage over the system board, under the keyboard) to make the machines less susceptible to abuse. We will se if this helps to reduce the hardware issues that officially don’t even exist.***

John

[cmarti]

Maybe holding it with both hands?
The cage will add more weight to you lappy

[davidspalding]

When I get my TP back, ... I am quite annoyed with the fact I had gone through 2 motherboard replacements in less than 2 weeks with normal use of the thinkpad!!!

Hrm.... "Normal use" ... "2 motherboard replacements in < 2 weeks" ... "normal use" ....

I think something's wrong here, either with your TP, or your "normal use," that a roll cage/strengthening home project will not cure. Either way, yes, a Port Replicator II or MiniDock will help support the bottom (and improve cooling, btw). But not if the force which is damaging the mainboard is coming from ABOVE. (And I would strongly discourage carrying the TP while docked; the docking connector and locking mechanisms clearly aren't designed to handle that kind of stress.)

All snarkiness aside, you may want to discuss the big picture with your support rep(s). Also considering how you're using it - are you carrying it in a book bag? are you carrying in a non-rigid, unpadded sleeve? are you possibly flexing the case in transit or during use?

All of these avenues will cost less time and expense than the one you're proposing.

[Jiro]

"normal use" as in sitting on my desk... stationary... If it happens again with the new motherboard i have not yet recieved I hope those guys figure out something else with it or replace it.

[darrenf]

It would be cheaper to upgrade to a T60, no?

-darren

[NovaxX]

I personally think that your normal use, i.e. sitting on a tabletop could not be an issue of flex unless your house sits on a fault line or u are frequently experiencing tremors of some sort.

I do think however, that you may have a faulty power supply or battery that my be causing the problem. I am suggesting that it may be caused by electrical fluxes that causes a power surge that is too much to take for your system.

If indeed that is the case, do consider either using a power-surge protected socket, or using a Uninterruptible Power Supply (UPS).

[davidspalding]

"normal use" as in sitting on my desk... stationary... If it happens again with the new motherboard i have not yet recieved I hope those guys figure out something else with it or replace it.

That is certainly NOT outside the bounds of gentle, normal operation. I like the Targus Coolpad Traveler as a cheap alternative to a slanted docking station. If by chance you are using a keyboard wrist rest at the back or something to slant the TP (I do that from time to time), that may be a cause of case flex,... but at this point, I think others are right, either you are working with dirty power (which a good AC adapter ought to insulate you from), or have a different internal problem -- bad power supply, short in the case, faulty fan,.... Your support org ought to escalate repairs from just endless planar replacements.

Best of luck....