L- Track Install on Floor

mattporter637

New member
After a lot of back and forth on how build out the inside of my 3500 I have finally decided to use L-track as well as 80/20 aluminum extrusion.

I would like some help from all the experts here on how to attach the L- track to the floor of the sprinter. Currently I have the stock composite flooring in the van with rattle trap underneath that. There is no sub- floor.

I am struggling with how to attach the L- track to the composite flooring since there is no space beneath and am not sure about drilling through the sheet metal floor.

Has anybody done this? What are the best options?
 

220629

Well-known member
...

Has anybody done this? What are the best options?
My opinion.

I would suggest using a combination of thru bolts and sheet metal screws.

I recommend pre-drilled L-track. I drilled and countersunk the first track I installed (2004 Sprinter). It was a pain in the a$$. For the 2006 the next L-track was ordered pre-drilled. I installed thru bolt fasteners where the undercarriage allowed. I used ss hardware for the 2006. Stainless has a bit less tensile strength vs steel, but the longevity made it the better choice (for me living in the rust belt northeast).

Start with as many thru bolts as you feel is required. Fill in the empty pre-drilled holes with sheet metal screws into the flooring.

For those concerned with the number of fasteners. The NCV3 OEM lengths of L-track are installed using just 3 each fasteners per length.

I will not even venture to suggest what the proper number and type of fasteners is needed for your installation.

:2cents: vic
 

sprinterPaul

Well-known member
After a lot of back and forth on how build out the inside of my 3500 I have finally decided to use L-track as well as 80/20 aluminum extrusion.



I would like some help from all the experts here on how to attach the L- track to the floor of the sprinter. Currently I have the stock composite flooring in the van with rattle trap underneath that. There is no sub- floor.



I am struggling with how to attach the L- track to the composite flooring since there is no space beneath and am not sure about drilling through the sheet metal floor.



Has anybody done this? What are the best options?


I drilled thru the floor. Checking for clearance first below. Thru bolted with fender washers in multiple locations. Use quality hardware.


Sent from my iPhone using Tapatalk
 

ptheland

2013 144" low top Passgr
Another one who bolted through the steel floor here. Since my son's life is literally hanging in the balance (I used L-Track for a wheelchair tie down point), I cut and drilled steel bar stock to go under the van. That trapped the floor between the bar stock and the L-Track. I also went straight to the steel floor, trapping the wood and laminate finished floor under a lip on the L-track. And I used every pre-drilled hole in the L-Track that I could access from the underside.
 

220629

Well-known member
The single point L-track tie downs in my purchased used 2004 commercial service wheelchair transport van have a single fastener with appropriate size back plate.

I used those to secure my Mom's wheelchair during transport.

The continuous lengths of L-track didn't use every provided pre-drilled hole. The L-track beam system is very strong. It could withstand the failure of individual fasteners without catastrophic results.

I'm not suggesting that a proper number of fasteners isn't necessary. I'm saying that there can be reasonable spacing of fasteners without creating a safety hazard. I'd be curious to see some pictures of actual failure of an L-track installation. I haven't found any to date.

"For lengthwise installation, use a minimum of four fasteners or
fasteners at 4” intervals, whichever provides the greater number of
fasteners."

There is no minimum spacing mentioned for the "minimum of four fasteners".

"The FE200762 and FE200765 are installed lengthwise with 3/8”
grade 5 hex head bolts on 8” centers."

https://sure-lok.com/wp-content/uploads/pdf_downloads/Safety_Information.pdf


:cheers: vic
 
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Wildebus

Member
The single point L-track tie downs in my purchased used 2004 commercial service wheelchair transport van have a single fastener with appropriate size back plate.

I used those to secure my Mom's wheelchair during transport.

The continuous lengths of L-track didn't use every provided pre-drilled hole. The L-track beam system is very strong. It could withstand the failure of individual fasteners without catastrophic results.

I'm not suggesting that a proper number of fasteners isn't necessary. I'm saying that there can be reasonable spacing of fasteners without creating a safety hazard. I'd be curious to see some pictures of actual failure of an L-track installation. I haven't found any to date.

"For lengthwise installation, use a minimum of four fasteners or
fasteners at 4” intervals, whichever provides the greater number of
fasteners."

There is no minimum spacing mentioned for the "minimum of four fasteners".

"The FE200762 and FE200765 are installed lengthwise with 3/8”
grade 5 hex head bolts on 8” centers."

https://sure-lok.com/wp-content/uploads/pdf_downloads/Safety_Information.pdf


:cheers: vic
Vic, I think the key part of the installation note you quoted is "whichever provides the greater number" - so 4" space between fasteners is the maximum design fastener gap (unless you had a very short piece less than 14" long I guess, but could that be used for wheelchair or seat locking if so short?)
We have the same tracking (called Unwin) in the UK with the same requirements. my current T1N (previously minibus with wheelchair provision) has around 14 lengths of it and my VW Eurovan (previously converted as wheelchair transport) had it also (and it took an age to remove all those bolts 4" apart , all going through floor with spreaders underneath)
This is the typical UK install spec: http://www.johnadamssupplies.co.uk/shop/unwin-rail/unwin-surface-rail/
- Surface rail requires M8 fasteners, fixed into countersunk holes at 101.6mm intervals for a flush head finish
- A 3.66m length of surface rail requires 37 fasteners
Pretty much identical to the US one once converted metric to imperial and in both my track-fitted vans, every single fastening hole was used with a proper bolt though floor or into a custom steel subframe.

Are they all needed for non-passenger use? I doubt it as the loads and enertia energy will be much less then a wheelchair (or ordinary seat) plus occupant subject to high G in a big accident (which is when all those fasteners become vital, not when just doing ordinary driving around)
 

220629

Well-known member
... (unless you had a very short piece less than 14" long I guess, but could that be used for wheelchair or seat locking if so short?)
...
There very well may be a minimum length for standard L-track for securing wheelchairs.

The single point anchors I have include a large bolt and backing plate.

https://www.discountramps.com/wheel...cket/p/Q5-7571-A/?CAWELAID=820562990000010420

https://www.discountramps.com/wheelchair-tiedown-regular-track/p/Q5-R/


Added:
I find it interesting that the shoulder harness bracket uses sheet metal screws.
https://www.discountramps.com/shoulder-belt-mounting-bracket/p/Q5-6500A-5/

and...
Turns out there is a short L-track anchor which uses only 2 ea. fasteners.
https://www.discountramps.com/wheelchair-tiedown-floor-pocket/p/Q5-7570-A/
The difference may be that the track in the PDF was going to secure 2 ea. straps to the wheelchair. The 2 ea. 5/16" fastener short track will only accommodate 1 ea. strap.

... Are they all needed for non-passenger use? I doubt it as the loads and enertia energy will be much less then a wheelchair (or ordinary seat) plus occupant subject to high G in a big accident (which is when all those fasteners become vital, not when just doing ordinary driving around)
Securing cargo is much different than transporting people. So that does get back to the general topic and away from wheelchairs.

:cheers: vic
 
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TheHerd

New member
Is there a good write up you can recommend for an L-Track Floor installation somewhere, that maybe I am missing when doing a search?

Interests and Concerns:
  • Anchor points and undercarriage reinforcement techniques
  • Alignment and Plywood cutout techniques
  • Plus/Riv-nut flathead screw/bolt use into sheet-metal, in holes between through-bolts
 

220629

Well-known member
Is there a good write up you can recommend for an L-Track Floor installation somewhere, that maybe I am missing when doing a search?

...
:idunno:

Opinions as to what is needed from an engineering view and what is needed for practical use vary. Installing L-track for general use will require less fasteners than L-track intended for seating installations.

Some people go to great lengths to design and install complex brackets under the truck. Personally I feel that when using thru bolts any decent backing will not pull through both the sheet metal and factory flooring. I've seen where sections of Unistrut/Superstrut have been used for backing. Galvanized trailer suspension parts are a possible source for plates.

My suggestion is to read as much as you need to make a decision.

Here's a few threads.

https://sprinter-source.com/forum/showthread.php?t=39700
https://sprinter-source.com/forum/showthread.php?t=42808
https://sprinter-source.com/forum/showthread.php?t=34694

You might do an advanced search using L-track specifying T1N, NCV3, or Conversion Write-up sections.

:cheers: vic
 

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