# Methods for attaching Tomy track to plywood from below



## Rolls (Jan 1, 2010)

Has anyone perfected any methods of attaching Tomy track to plywood from below? 

Long story short, my track will absolutely require at least some parts to be secured in place. I have 1/4" ply (luan) under much of my track and all the elevated sections. I'll certainly use track clips for certain parts and I've been looking at the usual suspects for securing other parts (caulk, countersunk screws a la Greg Braun, carpet tape, sinking the track into the table so it's flush, etc.).

Elevated sections on luan or other thin support seem unsuited to screwing down with wood screws because there's not enough wood to bite into. Countersinking is a lot of work on a long 4-lane and screw heads can be hidden, but not having them in the first place seems even cleaner.

Discussing options over beers, my brother suggested maybe screwing the track "up" from below. Has it been done? Any words of wisdom from those who've tried it so far?

Curious in California,

Rolls


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## 1976Cordoba (Sep 20, 2000)

Maybe use a dab of clear silicone at the screwposts to secure it to the table top.


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## Rolls (Jan 1, 2010)

Smart, 'doba. Good for sound insulation, too. Do you know if silicone comes off pretty easy down the road or does it become part of the track? Not a dealbreaker, but I'm curious if siliconed track pieces would clean up easily.

Thanks!!


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## Rolls (Jan 1, 2010)

*I can't believe it works!*

Apologies for my excitement in case this has been done a hundred times before, but it works!!!

And it's too easy. It'll take more time to post it that it did to do it.

I just laid a random piece of track on some luan:










Got some #8 machine screws and washers:










Marked from the top with a mechanical pencil with lead extended (this is key because it makes alignment of the screw from the bottom a piece of cake). (If you have a pin-sized bit you could just drill, but marking is just as good.


















Drill a hole. I did 3/16. Oversize lets the track move a little if it needs to. 










Screw the #8 machine screw through the luan or other material into the bottom of the track, using a washer or two for strength and to get the right depth. The screw self tapped perfectly into the plastic sleeve on the bottom of the track. Sweet.










And presto! Lovely attachment of track to plywood:










From above, there's only the tiniest hint that the track is secured - see the speck of silver visible through the hole. Sherlock Holmes could miss it.










Tomy track must've been designed for this, but it's under-publicized for sure. Some advantages as I see it are it takes no prep of the plastic and doesn't show from above. Works for 1/4" and thicker substrates, too. Use a plastic/rubber washer for sound insulation. Very precise control of the final height of the track bcs of the fine thread pitch of the machine screw. Handy for setups with carpet, sound insulation or other squishy stuff under the track. It doesn't muck up the track pieces at all, either.

A downside is it requires access to the track from below. It's not right for every situation, but it's good to have in your bag of attachment methods and it really shines for elevated track sections or any section you build as a module and then put into the overall track. I'm sure there'll be a piece or two that have holes bigger or smaller than the norm, too. 

I think it'll really help on parts of my track. I'm glad I listened to my brother on this one. Hope it helps someone else sometime, too.

Rolls


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## AfxToo (Aug 29, 2003)

This is a very good idea when it's an available option, especially for ultra lightweight luan-on-foam table construction. The _"A downside is it requires access to the track from below._" point is probably what excludes it from the vast majority of potential users. 

Another alternative for top-down attachement would be to use flat head threaded machine screws with washers and nuts underneath. Yes, this would require making countersink holes in the track. However, this would work where you do not have the ability to screw up into the target hole from underneath. McMaster Carr even sells black plastic (or nylon) screws/nuts that may work and not require painting.


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## slotcarman12078 (Oct 3, 2008)

The countersunk option can be tricky depending on the type of track though. There's a fine line between getting it just right and taking off too much (from first hand experience ) and having a big gaping hole where the small hole used to be! Good thing I tried with a 9" curve. :lol: The silicone does work, and using small dabs makes for less clean up if you decide to change the layout later. It does take a bit of time for the silicone to set up, but this gives you time to make sure everything is positioned correctly.


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## tjd241 (Jan 25, 2004)

*Sometimes no holes are needed...*

In my case, my track is permanent. The elevated section is adhered with Liquid Nails. Rather than take the chance of silicone giving or screws loosening... I shot a squiggle bead down with a caulk gun, weighted it down, and let it dry. On the right you can see that I even got the Tomy 15 inch straight to do a pretty nice dip to conform to the descent from the elevated overpass. It ain't comin up.


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## Rolls (Jan 1, 2010)

Hmmm... been thinking. The "requires access from below" actually might not be as restrictive as I thought at first. 

Stepping back from my original luan-influenced thinking, it occurs to me that even a flat track on a Greg Braun style table with 3/4" plywood does have some sort of access from below. So couldn't I secure, say, one of his 4x12 designs to a heavyweight table from below? I'm guessing so, though I sure haven't tested it.

To me, the real key to making this method viable is the ability to mark the hole to be drilled from above with the pinhole in the Tomy track, then drill down. That's what makes feeding the screw up into the plastic cylinder easy. Of course, that a #8 machine screw self taps pretty securely is pretty sweet, too.

So where does this non-traditional attachment method really make sense? Probably for any track design where these criteria are near the top of the list: 

1. invisibility of attachment when viewed from above
2. quiet (secure attachment to underlayment with sound insulation)
3. precise height adjustment for track smoothing or squishy material like carpet under the track
4. no clean up of track sections required when changing layout
5. works on very thin substrates (but not only thin substrates!)
6. unexplainable fear of machinist's t-handles or perhaps a strict objection to countersinking on religious or other grounds.

In that light, it's benefits are probably closest to silicone caulk in the portfolio of attachment methods. It's different from silicone in that it works with squishy tabletop coverings and requires no cleanup if track is changed/reused. Thoughts/opinions welcome.

Still might be useful to less than 1% of track building, but nice to have in the set of options. Hope it helps.

Rolls


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## slotcarman12078 (Oct 3, 2008)

I'm adding it to my memory banks!!! :thumbsup:


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## NTxSlotCars (May 27, 2008)

Well, eventually, the track gets secured down pretty well accidentally on purpose.
We usually have someone spill a Coke or sweet tea, or a tall thick syrupy cup of Dr. Pepper on the table, 
and that track ain't goin nowheres.


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## Rolls (Jan 1, 2010)

10, 2 & 4, as everyone in Dallas knows, right?


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## rbrunne1 (Sep 22, 2007)

This is absolutely brilliant :thumbsup:

Nice work Rolls 

I can't believe how nicely a #8 Machine screw taps into the plastic sleeve  

I think I know how I'm going to attach my track :freak:

Bob B.


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## Grandcheapskate (Jan 5, 2006)

This is a terrific idea. Thanks for giving it a try and sharing.

Here's another thought. The problem with using this method would be the need to have access from below. Assume you built a table with a thick solid plywood top. Would it not be possible to mount your track on a thin piece of wood (such as luan) and then secure that piece of wood to your plywood table top once the track is screwed down? This way, you can work on the track seperately from your table. Maybe even put a sound absorbing material between the luan board and your plywood top, although I do not know if that would deaden the sound.

I use Tyco track, but I'm sure the process is the same (I would have to check the size of the plastic sleeve. I'm guessing you could also fill the sleeves with something like Plastic Wood and then tap out a thread.

Joe


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## Rolls (Jan 1, 2010)

Grandcheapskate said:


> Assume you built a table with a thick solid plywood top. Would it not be possible to mount your track on a thin piece of wood (such as luan) and then secure that piece of wood to your plywood table top once the track is screwed down?


Hadn't thought of that. Sure would be possible. Nice idea, too.



Grandcheapskate said:


> Maybe even put a sound absorbing material between the luan board and your plywood top, although I do not know if that would deaden the sound.


I think that really makes the luan on tabletop concept sing. It seems the possibilities for sound insulation would really open up with your approach.

Nice!

Rob


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## slotcarman12078 (Oct 3, 2008)

*Just a thought....*

Sound deadening for a door track might be closer than we think with this method. It'll be a little tricky, but here's the thought. Prior to laying down the track, cement your vinyl covering to the door. Then mark out the holes of your track after laying it out on the door. Remove the track, and drill the holes with the appropriate drill through both sides of the door. Flip the door over and drill larger holes through just the bottom of the luan, big enough to get the whole screw/washer in and be able to get it in the hole. Instead of using a metal washer, use a plastic washer to snug the screws up to the track side of the luan. If my gut is right, between the vinyl covering and the plastic washer, the sound should be deadened considerably. Might be worth a try????


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## TopDogger (Apr 17, 2010)

I really like this method for hiding the screws. Well done.


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## slotnewbie69 (Dec 3, 2008)

wow.great thinking!dfeinately never thought of that before!thanks rolls!


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## rbrunne1 (Sep 22, 2007)

Bump...a must read for any new track builders


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