Installing picatinny rails on side of T97 FTU and custom bottom rails on handguard.

[unzari]

Any suggestions about how to go abouts doing this? The side rails on the FTU should be pretty straight forward.

For the bottom rail on the plastic handguard, any suggestions on how to mount a rail? I was thinking of filling in parts of the handguard where the screws are to be mounted with epoxy (or epoxy putty) to ensure strength and proper height before drilling and countersinking a nut on the inside.

Thoughts?

 

[F22_RaptoR]

I would use a Tee Nut of some sort to provide a wider seating area. Done this dozens of times to different guns, and never had any issues:

Epoxy the tee nut in place; and I would epoxy the picatinny rail on from the bottom as a bedding compound (use masking tape on the handguard to prevent overflow) If you really want to get froggy, add 1 or 2 layers of fibreglass cloth epoxied down between the tee nut flange and the inside of the handguard to widen the support, but this is overkill on a monumental level!

Realistically, 3 tee nuts on a 5" long picatinny rail section with the rail epoxied down and the tee nuts epoxied in, will be able to survive anything you throw at it. You'll break the gun before it'll come off

 

[unzari]

I would use a Tee Nut of some sort to provide a wider seating area. Done this dozens of times to different guns, and never had any issues:

Epoxy the tee nut in place; and I would epoxy the picatinny rail on from the bottom as a bedding compound (use masking tape on the handguard to prevent overflow) If you really want to get froggy, add 1 or 2 layers of fibreglass cloth epoxied down between the tee nut flange and the inside of the handguard to widen the support, but this is overkill on a monumental level!

Realistically, 3 tee nuts on a 5" long picatinny rail section with the rail epoxied down and the tee nuts epoxied in, will be able to survive anything you throw at it. You'll break the gun before it'll come off

Tee nuts, that's an excellent idea!
Would I be able to find these at my local hardware store or will I need to hunt them down at a specialty store? I also see one that takes 2 additional screws to secure the tee nut itself, which would make this process somewhat reversible, but since I am not planning on reverting this mod, epoxy would probably be the most simple and quick solution, and likely stronger.

Finally, do you suggest getting the tee nuts that span the thickness of the grip only or the grip plus rail and using a smaller gauge screw to secure the rail? I was thinking the former but that may introduce some play unless I use a different screw with a wider, un-threaded neck.

Thanks again!

 

[F22_RaptoR]

Tee nuts, that's an excellent idea!
Would I be able to find these at my local hardware store or will I need to hunt them down at a specialty store? I also see one that takes 2 additional screws to secure the tee nut itself, which would make this process somewhat reversible, but since I am not planning on reverting this mod, epoxy would probably be the most simple and quick solution, and likely stronger.

Finally, do you suggest getting the tee nuts that span the thickness of the grip only or the grip plus rail and using a smaller gauge screw to secure the rail? I was thinking the former but that may introduce some play unless I use a different screw with a wider, un-threaded neck.

Thanks again!

you can get these type at your local hardware store pretty easy in 10-32 (better) or 10-24 threads, but you have to cut off the tabs. I've used these kinds mostly, because they're easy to get, and if you leave a teeny bit of the tabs left, it can bite into the plastic and prevent it from rotating as you tighten it. The previous picture you can get those types at any industrial supply place like Acklands-Grainger etc... Not as common as home depot tho! (Home Depot carries the tee nuts in the rotating "fastener" bins)

Most of the time, what I do is drill the through-holes in the picatinny rail to the same size as the threaded neck on the tee nut (with the tee nut trimmed short enough that it won't hit the screw head, but still goes into the rail from underneath) so that you have a bit of a recoil lug from both sides. Once the screw clamps down it's rock solid.

You may or may not have to trim the tee nut neck down in length. If you do: having a little metal file and a tap is good for cleaning the cut end off, although in a pinch a diamond file - and putting the screw in from the opposite of the cut end - will let you clean up the end of the tee nut really well.

Then if you use the 15-hour cure JB Weld (it's stronger and more flexible than JB quick) it will give you time to clean up any overflow before it starts to cure. You have basically an hour to work it before it starts to cure.

 

[F22_RaptoR]

The Tikka in the middle has a 9" long picatinny rail added this way, 4 tee nuts and epoxied into place.

And this is my Ruger 10/22 before I epoxied the tee nuts in place, and painted the screws. A bit different with the support ribs inside.

The sling QD cup was installed prior to the picatinny rail.

 

[unzari]

The Tikka in the middle has a 9" long picatinny rail added this way, 4 tee nuts and epoxied into place.

And this is my Ruger 10/22 before I epoxied the tee nuts in place, and painted the screws. A bit different with the support ribs inside.

The sling QD cup was installed prior to the picatinny rail.

Thanks for the great advice! Will definitely give that a go and see where it takes me. Great work in those pics, looks professional! Must be doing this for a while!