seat track removal success

[mnexpress2]

oi!
so, i've been struggling with the seat tracks on a wheel chair accessible bus. anyone who's struggled with button head cap screws embedded in L-tracks knows how tedious it is. The best method i had before was getting under the bus and angle grinding the nuts off and hitting them with a punch upward. however, it's pretty cramped down there and the majority of the bolts are tucked neatly under gas tanks or other apparati. so, i was searching a way to stay in the bus and getting them out from above.


note - my bolts were rusted and there was unremovable black gunk around the nuts below. deep well sockets below and an impact wrench above with an allen key head had no effect for me.


so, i began with a 3/4 inch hole saw. the hole saw cannot have it's auger ... grade bolts are like gandolf ... even cobalt bits shall not pass. however, aluminum is a soft metal and the bi-metal hole saw it pretty useful. (pic 1) when i started i could drill around one bolt every 45 seconds or so. but after about 40-50 i spent minutes drilling around the bolt. i found that putting a claw hammer or crow bar under the L-track helped me to know when i passed through the aluminum (i didn't want to cut through the sheet metal and make a bigger hole in my floor(pic 2)). it makes a pretty satisfying pop once you get through. after you cut around all the bolts in track you can just lift it out.

then i tore up the plywood with a crow bar. as the tracks were counter-sunk in the plywood, i could cut the bolt heads with neither an angle grinder nor a sawzall. however, after getting rid of the plywood, the angle grinder demolished everything. (progression of this process pic 3-5)

use the punch to pound the headless bolt through.


the whole process took me about 2 hours, 4 hole saws and 4 angle grinder discs. thanks doost rooskie and shane!

[Native]

Seems like you have thought up a very decent way to handle those tracks!

[jofred99]

Looks like a great way to remove the floor rails!


Assuming that you also had shoulder strap rails, how did you remove those? Mine are bolted above the windows and there is no space for a socket to fit in.

[Mountain Gnome]

Originally Posted by jofred99

Looks like a great way to remove the floor rails!


Assuming that you also had shoulder strap rails, how did you remove those? Mine are bolted above the windows and there is no space for a socket to fit in.

I had the same problem. You have to find thin-walled sockets. I used one from a set of uncommon impact sockets. You might try to find a Snap-On brand socket.


One or two of the bolts were just off-center enough that no socket fit. I used a Dremal with a mini cut-off wheel to hack away at the aluminum rail around the head of the bolt. In my case, I wanted to save the rail and re-install it. I'm building all modular stuff in my bus that bolts to the wheelchair tie-downs on the floor and my shelves use the ones on the walls above the windows. In the future, I can move things around. I can add or remove things without adding or filling additional holes in the bus body.

[EastCoastCB]

I wonder how well it would work just to take a $2 socket and sand it down enough to get those fasteners out.

[Mountain Gnome]

Originally Posted by EastCoastCB

I wonder how well it would work just to take a $2 socket and sand it down enough to get those fasteners out.

The clearance was just micrometers out.
That is a good idea!

[EastCoastCB]

That may a good use for a Harbor Freight socket.
Attach it to a drill or something that spins and sand it down.

I'm just glad I've never had that seat track stuff. Mine have always just been plates bolted to the floor like the seats are.

[jofred99]

Originally Posted by Mountain Gnome

I had the same problem. You have to find thin-walled sockets. I used one from a set of uncommon impact sockets. You might try to find a Snap-On brand socket.

Great idea!

This is one of those times that I wish I had a metal lathe in the shop. Might be able to remove enough side wall on the socket to remove the bolt.

[jofred99]

Almost feel a little slow about posting my solution, but here goes.

First, I lined up my socket points with the bolt head that I was attacking. Please remember from here out that I use Harbor Freight tools, not Snap On. Also remember that the socket is just millimeters from fitting in the space where the bolt head is. Then I gently tapped the socket into place with a 10 lb. hammer and removed the bolt.

Worked for all 10-12 bolts that held the rails in place.

Sometimes ya have to get a bigger hammer.


Now on to the floor rails...

[o1marc]

Make sure the socket is a 6 point and not a 12 point.

[EastCoastCB]

Originally Posted by jofred99

Great idea!

This is one of those times that I wish I had a metal lathe in the shop. Might be able to remove enough side wall on the socket to remove the bolt.

Should be do-able.

[Native]

I really like the "sand it down" idea and the "bigger hammer" idea. Thank you all for sharing your great inspirations.

[joeblack5]

Great solutions to write a wiki about... Love the gentle tap with a 10 lbs hammer.

Johan

[gibgib]

Hi! I'm having this same problem, what kind of hole saw bit doesn't have an auger?

[musigenesis]

Originally Posted by gibgib

Hi! I'm having this same problem, what kind of hole saw bit doesn't have an auger?

He meant a hole saw without its pilot bit (they're usually removable by removing a small set screw). The pilot bit would be stopped by the bolt head so it needs to be removed first.

[Rivetboy]

I feel your pain as last weekend we removed all off my channel also. The method we used was one guy on the bottom with a 3/8 drive impact, 1/4 ratchet etc. The guy on top grabbed the bolt with a pair of vice grips and the bottom guy removed the nut. On the ones that were not accessible, they were just ground off on top with an angle grinder. It took most of the day but now it is done, Amen. On a few of them it was easier to cut the track with the grinder and unscrew it from the top PITA any how.

[Delos356]

I had some good luck with a slightly different method. I used a sawzal with a carbide demo blade (a longer one) under the track to cut the bolts, but with a buddy with a long pry-bar to lift up on the tracks to relieve some of the pressure. I put the blade in the saw horizontally instead of vertically, and then used the saw upside down so the blade was horizontal (parallel to the floor) and very close to the floor.

We had 16 tracks in our bus, and it took over 4 hours to remove the first 4 while I struggled to figure out a method. Without a pry-bar to lift up on the track the compression just kills the reciprocating saw. Once I figured that out, it took 2 hours to get the other 12 tracks out!