Custom seat bracket

Just bought GTI golf seats for my Ford fiesta mk6 and of course the mounting points to the floor dont line up I was thinking of getting 4mm aluminium checker sheet and attaching the checker sheet plate to the seat with lock tight nuts and bolts and fastening the sheet down to the floor with the original bolts would this be secure enough

Only a qualified mechanical engineer, armed with the right CAD tools and background engineering information of the original car design would have any chance of providing that information. Do you have any background in materials science? Do you know which material or hardness grade bolts would do best under those stresses?

It’s not what happens under normal usage, it’s what’s going to happen in a severe accident. And if your seat or worse yet your occupied passenger seat fails, the result will be on your head. No insurance company will cover you for a modified seat mount either.


In addition to TwinTurbo’s on-target comments, I have to wonder if the “new” seats have passenger sensors that can be connected to the airbags, and–if so–if VW seat sensors are compatible with the SRS system of a Ford. Somehow, I doubt if they would be compatible, thus potentially making the airbags useless in the event of a collision.


I dunno but I’ll be a little more permissive. Having repaired and replaced the seat channels in my Buick several times, I can tell you that factory seats in themselves are no great engineering feat designed to keep the seat in the car during a crash. Often they are thin aluminum. Now the seat belts themselves will be anchored more securely so that in a crash the belt will hold the seat, not the seat anchors. So I guess I’m saying if you at least exceed the strength of the original track, it should be OK but understand the plate may not be the same alloy as the original. Might want to see if just drilling new anchor holes would work or using channel or something more substantial.

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Can’t speak to your question directly, not enough experience. But if I were making a diy’er adapter for that purpose I’d use steel rather than aluminum. Just to be on the safe side. Same thickness of steel as is used on the oem bracket. Same grade of bolts too.

Because of the length of my legs I have made custom seat brackets for some of my cars. don’t know if the steel I used was 3/16 or 1/4". It was just some I had laying around.

And you’re basing this on…?
It looks like thin aluminum to you so it can’t possibly hold up in an accident? Is that it?

Do you know how many alloys of aluminum there are?
Do you know the various strengths of these alloys under the stresses they are expected to endure?
Have you looked at the shape they are formed into and determined how that might affect their deformation under load?
I can assure you the mechanical engineers that designed the seats and their mounts know every single detail. They have not only modeled it, but they have examined those seats and their mounts after empirical crash testing. And the seat is designed to remain attached to the chassis under all but the most unusual stresses…

I don’t even know what to say about this. Imagine where the stresses of the seat mass will be transferred if it departs from the floor. Who might be between the seat and the belt? Is that how you would expect them to design it?


I would drill new anchor bolts but one of the rails doesn’t reach the hump the seat sits on (shown in photo if it loads) my original plan was to use 6mm mild steel bar on all 4 coners but I read that it will be hard to work with but that’s also the reason why I want to use it was maybe thinking use the mild steel and 2mm sheet metal connecting the coners for more rigidity

Well they might have known every single detail but I can assure you after I welded up the cracked floor mounts, they were twice as strong as the original.

If you were in a third world country your vehicle may not be equipped with passive restraints.

From that coin on the carpet it appears that you are in Canada, your car should be equipped with an occupant classification system. This includes seat track position sensors, an occupant classification bladder w/module in the passenger seat and other important components. I don’t believe that you will ever get the passive restraint system operating with VW seats installed.


It’s a 20p I’m from northern Ireland

George you seem like you have more experience than me with materials what if I used 6mm thick and 3 inches wide mild steal on all 4 corners would that be sturdy enough base for a seat to sit on

Nobody in this forum would recommend that you steal anything.
Surely there must be a supplier from whom you can buy the correct-spec steel for this project.

However, that still doesn’t address the issue of the seat sensors, and the likelihood that this modification will render your airbags useless.

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Seat sensors can be on i dont mind not a road car also the air bags are took out

I just want to know would my method have enough structural integrity to hold my seat in place while I drive or if anyone has any other way to do it looking to spend under a 100 pound the universal seat brackets are 140 each


If you can actually acquire universal brackets then why would you even mess with a make shift solution that might not be safe. Not a road vehicle then what is the thing to be used for ?

Demolition Derby?

I dont have that sort of money is the case just looking for another solution metal will only cost about £60 £70

Like I said, the weak points are those tabs that bolt to the floor. They are really not very heavy metal. I’ll concede with Turbo that they may be a higher alloy but when mine broke, they welded up just fine. I think you can use metal similar but I’d make them a little heavier. If you want you can weld up the platform as shown or similar using decent thickness steel. Contrary, I don’t believe it is rocket science-just trying to secure the seat.

If I were making it, I’d probably use steel flat stock. Drill and bend the mounts and weld the tabs on another length of flat stock, then weld two cross lengths to make the platform with the holes drilled to mount the new seats. Seems like a lot of money for steel though. I usually get a load of angle and flat stock for about $50.

Yeah I’m not an engineer but do make stuff in my spare time.