# Counter top for a R/T?



## Jim.S (Apr 13, 2020)

I want to build a router table and feel that the top will dictate size, style and so on.

I have new counter top (sink cutouts) available for zero cost.
The largest router I am going to mount in this table is my Triton tr001.
I plan to use the same table to swap other routers in and out by using router plates of the same size.

OK - here is the question, does anyone think that the counter top is stout enough to support the triton?
If the strength of the one inch thick counter top (made of particle board) appears to be a problem I plan on increasing the strength by adding a few angle iron supports.

I would appreciate anyones opinion.

Thanks-Jim S.


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## DaninVan (Jan 1, 2012)

Jim; i guess that answerd my question in your introduction, re which router!


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## Stick486 (Jan 4, 2013)

Jim.S said:


> I want to build a router table and feel that the top will dictate size, style and so on.
> 
> I have new counter top (sink cutouts) available for zero cost.
> The largest router I am going to mount in this table is my Triton tr001.
> ...


put a torsion frame under the top...
do the joints/intersections w/ edge half lap joints...

.


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## RainMan 2.0 (May 6, 2014)

Plus one on the torsion box


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## sreilly (May 22, 2018)

Jim while a torsion box would be mega support what is important is that the surface is perfectly flat and remains so. It also needs to be supported so it can not flex. A top can be a simple flats supported piece of wood and a straight piece of wood for a fence using clamps to secure the fence. From there it can go most anywhere. What should determine size would be its likely use. Trying to route large pieces on a small table can be near impossible. Think about your usage and look at tables on the market. Generally there are 2 sizes, the small portable and the shop dedicated. From there it can go anywhere. Also don't forget the table saw add on router tables as an option. This really becomes a personal choice. I built a dedicated table which is used most often but also bought the cast iron table for my Sawstop because I have the Inca LS Positioner and Wonder fence on my table saw which evolved later on in my shop expansion.


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## mbrun (Jan 12, 2020)

You can certainly using counter top material for a router cable. However, because it is made of particle board, it will sag in time with the weight of a router set into it. 

Angle iron would be an excellent support. Others have done that. You could achieve the same net effect using strips of hardwood underneath all perimeter edges and then side-to-side and front-to-back. In effect, similar to the torsion box concept Stick suggested, but with the necessary opening for the router/router lift. Here is an underside view of the one I use. Members are 2-1/2” tall. Notice the side to side members in front of and behind the box. In my case, the dust collection box also serves to provide front-to-back support since it is attached to the front and middle side-to-side support members.











Sent from my iPad using Tapatalk


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## Jim.S (Apr 13, 2020)

Thank-you - Everybody.
The torsion box looks strong and should be a fun build for a newbie with a new router!

The other methods look pretty easy for someone like myself (used to flatwork).
I have intended from the start to put everthing in a box as MBRUM suggested because of dust collection and the orderlyness it creates.

By the way, my future posts should have my name included. My bad. I'll blame it on being a newbie.

See you folks in the sawdust pile.


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## Nickp (Dec 4, 2012)

:grin:


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## Stick486 (Jan 4, 2013)

Jim.S said:


> Thank-you -
> The torsion box looks strong and should be a fun build for a newbie with a new router!


strong doesn't quite cover it well enough...
use your table saw and a dado blade for the joints...
search ''torsion box''.. lots of hits..
*here's a thread* you might want to read...

rim joints for a torsion box...


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## Stick486 (Jan 4, 2013)

Jim.S said:


> I have intended from the start to put everthing in a box as MBRUM suggested because of dust collection and the orderlyness it creates.
> 
> By the way, my future posts should have my name included. My bad. I'll blame it on being a newbie.


thanks for name inclusion...

*DUST COLLECTION*​
There is some information on dust collection w/ your health in mind *at this here link* if you need it...


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## roxanne562001 (Feb 5, 2012)

I have been using a sink cut out for years with 3hp Hitachi M12 V with no problems.


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## DesertRatTom (Jul 3, 2012)

I have a plarticle board outfeed table on my table saw. I have 1x3 hardwood trusses crossing underneath and it has stayed perfectly flat for 12 years so far. Another method is to add a second layer of very flat ply or MDF (which is very flat). If you use MDF for the second layer, you must pre drill for any screws you might use to attach it. You can add trussing as well, but don't crowd the trusses too close to the router, they can get in the way of your Triton when you reach for the lock lever or on switch.


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## kp91 (Sep 10, 2004)

I used a counter top cut off for a couple of years, no issues.


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## ger21 (Feb 10, 2019)

The strength of a torsion box comes 100% from the strength of the glue bond between the ribs and the skins. The ribs can be butt jointed, and don't even need to touch. While rabbets, dadoes, notches, and any other joints might help in assembling the box, they add zero strength, but may add a lot of time.

One thing to consider with a torsion box is that you need to make sure there's enough clearance underneath. I just got rid a torsion box table saw extensions table / router table, because the thickness was too restrictive, due to the thickness of the top.

If the countertop has laminate on both sides (unlikely?), then it will sag. It need laminate on both sides for stability, in effect making it a thin torsion box.

My new extension/router table is 3/4" baltic birch with laminate on both sides. I also plan on attaching some 1/4" thick aluminum angles on the bottom to increase stiffness.


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## Stick486 (Jan 4, 2013)

a simpler image of a torsion grid...

.


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## Cherryville Chuck (Sep 28, 2010)

A few years back I built a temporary table that got used for about 6 years. It was a scrap piece of melamine coated particle board maybe a hair bigger than a sink cut out. I wanted to try t tracks for holding the fence in place so that only left 1/4” of material where they were but I added supports under them and that strengthened those sections enough. I laid the sheet onto a ladder style frame with supports close to the cut out for the plate too. Joined the top to the frame with biscuits. It sat in a shed that went from -40 in winter to plus 40C in the summer and was still dead flat after 6 years. 

The short answer is yes it will work. Sometimes a small table is preferable to a large one. A piece with some warp may bridge across a long table but be okay on a shorter table. Lee Valley made a steel table top that had a slight rise to the centre that was there to prevent bridging.


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## JOAT (Apr 9, 2010)

Stick486 said:


> put a torsion frame under the top...
> do the joints/intersections w/ edge half lap joints...
> 
> .


Yeah, my router table has a sort of torsion box, and a 1/2" plywood top. Hasn't sagged a bit in the 10-15 years or so since I made it. My torsion box is made of chunks of 2X4 glued together tho. Longest chunks is maybe 8", looks like a spider web under the top. I glued them together (still haven't figured out how I did that, on a flat surface, then when the glue dried, flipped so had a nice flat surface to glue the plywood on. The top is in 3 pieces, and the plywood router plate sits in the cut-out, with a perfect fit. And still trying to figure out how I did that too. All I actually know is, I knew I needed a router table, no idea how to do it, so grabbed a chunk of 2X4 or plywood, and the rest is a blank, until it was finished, and not a clue how I did it. Zen woodworking.


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## RainMan 2.0 (May 6, 2014)

I forgot all about this ,but here was my attempt at making a torsion box router table replacement wing for my tablesaw . 
Unfortunately it failed because I used pocket screws to attach the torsion box to the top . It caused some warping and ended up being a wright off, as I had glued everything not knowing I had distorted the tops level ness after I had screwed them all down . A lot of work and time down the drain,as I done my first laminate job to , and it turned out great . 
If I did it again I’d only glue the boards and not even use pocket screws , or add the screws *after* the glue had dried . 
Also, I’d spend more time getting the lap joints just right , as they ended up being a little on the tight side when I went to assemble them . 

You’ll notice I got lazy and didn’t add some of the cross members, but I believe it would have been plenty strong . 
It’s only holding up a PC690 and a plastic duct collector. You’ll notice I didn’t cut in the aluminum plate yet , as that was the last step , but as I mentioned the top had a minor warp so it was discarded


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## Jim.S (Apr 13, 2020)

I have viewed all of the wonderful comments regarding a router-table top. My original concern regarding strength has been answered quite well.

I am going steer away from the counter top approach. I live in Virginia and we have humidity that is awful in this part of the country. I have been told of unused counter tops swelling over a few years because of humidity in an unconditioned garage.

I am going to use two layers of middle grade plywood covered by a ½ inch sheet of MDF. Then I am going to cover the MDF with Formica or hardboard. I know that this may not be the flattest outcome, but I do word working for fun. Besides If what I make goes bad, I can learn from the first attempt.

I thank the following contributors because their comments gave me a lot to think about. I do not wish to step on any toes, so if I did not use your suggestion / approach and you feel like I am making an apparent bad move please let me know.

DaninVan --- Stick486 --- RainMan 2.0 --- sreilly --- mbrun --- Nickp --- roxanne562001 --- DesertRatTom --- kp91 --- ger21 --- Cherryville Chuck --- JOAT


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## Cherryville Chuck (Sep 28, 2010)

I’ve seen a number of posts by people who laminated plywood together and it warped on them. I personally believe it was the glue that did. Glue sets when the water dries. There’s no where for the water to go in the middle of a plywood sandwich but into the plies at the Center of it. That causes the warping I believe. I personally would never do it although some have and been successful. I’ve found no need to since if you attach one layer to a level frame you’ll be fine. Think of the floor under your feet and how it’s built.


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## Jim.S (Apr 13, 2020)

Wow, that is major interesting! Now I have to rethink my approach. 

The laminate shouldn't cause any issues because it uses contact cement, therefore no H2O.

I may try this approach with construction adhesive and give it a shot on a small 1 foot X 1 foot sample in order to check out the plywood and MDF.
If that fails I suppose I will have to go all MDF. The only issues I have ever had with gluing MDF is that you better understand the clamping process or you will get an uneven surface.

I have a feeling that construction adhesive doesn't contain that much liquid when compared to a wood glue like Titebond. 

If anybody is interested, Locktite manufactures an excellent construction adhesive.


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## Stick486 (Jan 4, 2013)

Jim.S said:


> I am going steer away from the counter top approach. I live in Virginia and we have humidity that is awful in this part of the country. I have been told of unused counter tops swelling over a few years because of humidity in an unconditioned garage.
> 
> I am going to use two layers of middle grade plywood covered by a ½ inch sheet of MDF. Then I am going to cover the MDF with Formica or hardboard. I know that this may not be the flattest outcome, but I do word working for fun. Besides If what I make goes bad, I can learn from the first attempt.


good move on the steering away from the piece of counter top...
I believe a single layer/sheet of phenolic coated Baltic Birch on top of a torsion grid made from BB also is the way to go...
all glued together w/ PL Premium construction adhesive and not wood glue...

*Note:*
high humidity is very unkind to MDF...


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## roxanne562001 (Feb 5, 2012)

Jim.S said:


> I have viewed all of the wonderful comments regarding a router-table top. My original concern regarding strength has been answered quite well.
> 
> I am going steer away from the counter top approach. I live in Virginia and we have humidity that is awful in this part of the country. I have been told of unused counter tops swelling over a few years because of humidity in an unconditioned garage.
> 
> ...


Hi Jim I live on the Georgia Florida Border talk about humidity!! I just painted the exposed area of the sink cut out with 3 coats of Polyurethane it lives out in an unheated uncooled shop and even in the back of my truck sometimes I have had my portable router table setup for 20 plus years I never had trouble with swelling. If you use MDF it is not good in high humidity areas either.


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## RainMan 2.0 (May 6, 2014)

ger21 said:


> The strength of a torsion box comes 100% from the strength of the glue bond between the ribs and the skins. The ribs can be butt jointed, and don't even need to touch. While rabbets, dadoes, notches, and any other joints might help in assembling the box, they add zero strength, but may add a lot of time.
> 
> One thing to consider with a torsion box is that you need to make sure there's enough clearance underneath. I just got rid a torsion box table saw extensions table / router table, because the thickness was too restrictive, due to the thickness of the top.
> 
> ...


I never would have thought about laminating both sides, makes sense


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## ger21 (Feb 10, 2019)

Even better is to use a rigid glue to laminate, but you'll need a press. Contact cement isn't bad, if done right. But there's a night and day difference when laminating in a press with a more rigid glue.


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## ranman (Oct 27, 2017)

Cherryville Chuck said:


> I’ve seen a number of posts by people who laminated plywood together and it warped on them. I personally believe it was the glue that did. Glue sets when the water dries. There’s no where for the water to go in the middle of a plywood sandwich but into the plies at the Center of it. That causes the warping I believe. I personally would never do it although some have and been successful. I’ve found no need to since if you attach one layer to a level frame you’ll be fine. Think of the floor under your feet and how it’s built.


Chuck, I'm wondering if people glued the plywood with both pieces with the same side up. Plywood with one side sanded has one thin side..... The show side. In my experience, plywood warps partly because one side is sanded thinner. Had they flipped one sheet and given it a quarter turn, that probably would have helped. That said, the plywood needs to be really flat to start with.


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## Stick486 (Jan 4, 2013)

ranman said:


> Chuck, I'm wondering if people glued the plywood with both pieces with the same side up. Plywood with one side sanded has one thin side..... The show side. In my experience, plywood warps partly because one side is sanded thinner. Had they flipped one sheet and given it a quarter turn, that probably would have helped. T*hat said, the plywood needs to be really flat to start with*.


Baltic Birch is usually the answer for that...
not to be confused w/ Birch plywood


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## Cherryville Chuck (Sep 28, 2010)

ranman said:


> Chuck, I'm wondering if people glued the plywood with both pieces with the same side up. Plywood with one side sanded has one thin side..... The show side. In my experience, plywood warps partly because one side is sanded thinner. Had they flipped one sheet and given it a quarter turn, that probably would have helped. That said, the plywood needs to be really flat to start with.


There is a plywood mill near home that my brother in law worked at when young. The plies went through a drier just before being pressed together plus the glue is a hot melt resin powder so the process is pretty hot. I used to hear about press “blow outs” which I assume were caused by excess moisture turning to steam and creating too much pressure. I was told that the cause for wonky plywood as too hot coming out of the press and not cooling properly. I think that mill made mostly sheathing plywood so quality was probably secondary to price. But it does seem to be getting harder to get good quality ply that is well glued, not full of voids, and flat and stable.


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## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> There is a plywood mill near home that my brother in law worked at when young. The plies went through a drier just before being pressed together plus the glue is a hot melt resin powder so the process is pretty hot. I used to hear about press “blow outs” which I assume were caused by excess moisture turning to steam and creating too much pressure. I was told that the cause for wonky plywood as too hot coming out of the press and not cooling properly. I think that mill made mostly sheathing plywood so quality was probably secondary to price_. But it does seem to be getting harder to get good quality ply that is well glued, not full of voids, and flat and stable_.


go Baltic Birch or Apple Ply...


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## RainMan 2.0 (May 6, 2014)

Stick486 said:


> good move on the steering away from the piece of counter top...
> I believe a single layer/sheet of phenolic coated Baltic Birch on top of a torsion grid made from BB also is the way to go...
> all glued together w/ PL Premium construction adhesive and not wood glue...
> 
> ...


Never thought of using construction adhesive instead of glue . Would there still be an issue with warping if your bonding the torsion box to phenolic board with glue ?


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## Cherryville Chuck (Sep 28, 2010)

Rick is just make sure the tube is fresh and warm and that you apply it in uniform beads close together so that there aren’t hills and valleys. If the ply is flexible enough it could be a bit wavy because of a bad glue job. Maybe even better is to apply enough that it could be spread with a notched spreader or use glue from a can meant for flooring that gets spread with a notched spreader. That would give the most uniform bond. 

Where you and I live particle board, mdf, or ply are all okay. There isn’t enough humidity in either of our valleys to cause problems.


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## Herb Stoops (Aug 28, 2012)

Cherryville Chuck said:


> Rick is just make sure the tube is fresh and warm and that you apply it in uniform beads close together so that there aren’t hills and valleys. If the ply is flexible enough it could be a bit wavy because of a bad glue job. Maybe even better is to apply enough that it could be spread with a notched spreader or use glue from a can meant for flooring that gets spread with a notched spreader. That would give the most uniform bond.
> 
> Where you and I live particle board, mdf, or ply are all okay. There isn’t enough humidity in either of our valleys to cause problems.


I was thinking the same thing, Const adhesive is quite thick and it would take a commercial press to get enough pressure to flatten it out.
HErb


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## Stick486 (Jan 4, 2013)

Herb Stoops said:


> I was thinking the same thing, Const adhesive is quite thick and it would take a commercial press to get enough pressure to flatten it out.
> HErb


at room temp it is quite pliable and easy to work.....
no press needed...
usual clamping or some mechanical fastening...
just remember it expands some so let it cure before removing the clamps....
and a little goes a long ways...


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## ranman (Oct 27, 2017)

Stick486 said:


> Herb Stoops said:
> 
> 
> > I was thinking the same thing, Const adhesive is quite thick and it would take a commercial press to get enough pressure to flatten it out.
> ...


I'd be thinking something like a 1/16th by 1/16th flooring trowel, then a lot of pre placed temporary one inch drywall screws.


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## Stick486 (Jan 4, 2013)

ranman said:


> I'd be thinking something like a 1/16th by 1/16th flooring trowel, then a lot of pre placed temporary one inch drywall screws.


more like a 3/8'' wide by 1/8'' thick bead.... 
you snap off 1 or more of those DW screws and thinks will go south in a hurry...
besides, DW screws aren't designed to draw down and that radical bugle head will damage your top...

use Modified Trusshead, K-lath or GRK screws instead... you won't crack the top using these styles of screws...

















drill a clearance hole for the screw in the top and a pilot hole in the torsion member...
I find a tapered drill bit is perfect for the job...


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## ranman (Oct 27, 2017)

Stick486 said:


> ranman said:
> 
> 
> > I'd be thinking something like a 1/16th by 1/16th flooring trowel, then a lot of pre placed temporary one inch drywall screws.
> ...


I was thinking the no-show side.
Before I knew better, I used drywall screws for a lot of underlayment and other things. Extremely rare occasion when I snapped one. I bought the fine thread ones. Discovered early on that if you apply a decent amount of downward pressure when screwing, forcing the screw in, they don't break. 
However if you just lightly hold the drill and make the screw do all the work to draw the materials together they snap off a lot.
Also, there are El cheapo drywall screws and ones of pretty good quality out there...... used to be anyway. I don't use em much anymore.
I fastened plywood tool racks to the structural rails on the inside of my van 30 plus years ago..... drove them through the plywood and into the metal without pilot holes. Van is rusting into oblivion, but screws are still holding fine. The tool racks are probably holding the van together. 😄
I use staples for underlayment, torq head deck screws for heavier underlayment or structural projects.


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## Cherryville Chuck (Sep 28, 2010)

The only thing drywall screws get used for up here is drywall. We can go to the hardware store and buy bulk square drive by the pound like everyone else buys nails. With drywall the driver has to disengage from the bit as soon as the head goes below the surface and a square drive wouldn’t disengage so they don’t make them in anything but Phillips. Too bad in a way because I like how sharp they are. It isn’t easy to find the regular screws with a self drilling tip. GRKs are good but a little pricey.


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## RainMan 2.0 (May 6, 2014)

Cherryville Chuck said:


> Rick is just make sure the tube is fresh and warm and that you apply it in uniform beads close together so that there aren’t hills and valleys. If the ply is flexible enough it could be a bit wavy because of a bad glue job. Maybe even better is to apply enough that it could be spread with a notched spreader or use glue from a can meant for flooring that gets spread with a notched spreader. That would give the most uniform bond.
> 
> Where you and I live particle board, mdf, or ply are all okay. There isn’t enough humidity in either of our valleys to cause problems.


I wasn’t concerned about the moisture content in the air ,but the moisture of the glue warping the ply as it drys . I thought that’s why Stick mentioned construction adhesive.

Btw if I ever make a table , it will be with that phenolic stuff . You’ll here me curse from where your at when I screw up the opening for the plate


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## Stick486 (Jan 4, 2013)

RainMan 2.0 said:


> 1... I thought that’s why Stick mentioned construction adhesive.
> 2... when I screw up the opening for the plate


I remember you telling me to shut up and go sit down when you got pissed off because you skipped a step or two, didn't follow sequence and got in hurry on some other operations...
so this is for the readership...

1... I said to use it for it's strength, it's forgiveness, permanentence, performance and it's ability to bridge voids w/o strength compromise...
2... that is screw up proof... 
and you can bet the bank I don't/didn't use MDF... 
I ceased and desisted w/ that garbage many decades ago; it generated issues, recalls and hurt the bottom line...
for the RT's top I like Phenolic or HPL coated Baltic Birch or Apple ply... 
same for the Torsion grid but w/o the Phenolic or HPL...
stability and strength works for me...

*Notes:*
Top bearing mortising (radii to match the plate's corner's radii) bit is just the ticket to make the rabbet...

.


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## Stick486 (Jan 4, 2013)

@Jim.S...

I may have missed it or it wasn't mentioned...
seal the bottom and edges of your top w/ a polyurethane (type) non-breathing coating....
as in get as close to waterproofing it as you can...


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## mbrun (Jan 12, 2020)

BTW, I used a double (perhaps triple) coat of contact adhesive when I glued the layers of BB together for my router table extension. I definitely used three on the wood and two on the PL when I laminated the PL to the wood.











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## Stick486 (Jan 4, 2013)

sweet!!!


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## Jim.S (Apr 13, 2020)

Cherryville Chuck said:


> A few years back I built a temporary table that got used for about 6 years. It was a scrap piece of melamine coated particle board maybe a hair bigger than a sink cut out. I wanted to try t tracks for holding the fence in place so that only left 1/4” of material where they were but I added supports under them and that strengthened those sections enough. I laid the sheet onto a ladder style frame with supports close to the cut out for the plate too. Joined the top to the frame with biscuits. It sat in a shed that went from -40 in winter to plus 40C in the summer and was still dead flat after 6 years.
> 
> The short answer is yes it will work. Sometimes a small table is preferable to a large one. A piece with some warp may bridge across a long table but be okay on a shorter table. Lee Valley made a steel table top that had a slight rise to the centre that was there to prevent bridging.


That is what I would have to call common sense logic. 
I also have to remember that I am pushing 80, do I really need a R/T that will outlast me?

Thank-you for your logical information. I really do appreciate it.

I am sure that it will be part of the guide that helps me get this simple task a bit more uncomplicated.


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## Jim.S (Apr 13, 2020)

kp91 said:


> I used a counter top cut off for a couple of years, no issues.


Doug - because of yours and roxanne562001 comments this approach has not been completely dismissed.

However, sometimes my decisions are placed in a compound that is more like wet sand than cement. 
I get to change my mind along the way based on the project.

Thanks for your input.


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## Jim.S (Apr 13, 2020)

DaninVan said:


> Jim; i guess that answerd my question in your introduction, re which router!


Ideas change as time passes. 

I haven't said anything before but part of my plan is as follows.

Build the top and R/t for my Triton using the purchased plate for the Triton.
Make plates drilled for the Porter cable and the Bosh that are the same overall size.

One table for three routers. Almost a necessity in a small shop.


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## Jim.S (Apr 13, 2020)

mbrun said:


> You can certainly using counter top material for a router cable. However, because it is made of particle board, it will sag in time with the weight of a router set into it.
> 
> Angle iron would be an excellent support. Others have done that. You could achieve the same net effect using strips of hardwood underneath all perimeter edges and then side-to-side and front-to-back. In effect, similar to the torsion box concept Stick suggested, but with the necessary opening for the router/router lift. Here is an underside view of the one I use. Members are 2-1/2” tall. Notice the side to side members in front of and behind the box. In my case, the dust collection box also serves to provide front-to-back support since it is attached to the front and middle side-to-side support members.
> 
> ...


I guess one could call your approach a "non-conventional" torsion box.
I also get your comment regarding the dust collection box. I had not gotten my head all the way around Stick's approach, but now I see it.
The picture really is worth a thousand words. 

Thanks


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## Jim.S (Apr 13, 2020)

DesertRatTom said:


> I have a plarticle board outfeed table on my table saw. I have 1x3 hardwood trusses crossing underneath and it has stayed perfectly flat for 12 years so far. Another method is to add a second layer of very flat ply or MDF (which is very flat). If you use MDF for the second layer, you must pre drill for any screws you might use to attach it. You can add trussing as well, but don't crowd the trusses too close to the router, they can get in the way of your Triton when you reach for the lock lever or on switch.


 I am leaning more towards the approach Charles (MBRUM) has taken. His approach appears to be very similar to yours and I am pleased that multiple router users are using similar approaches.

Thank-you so very much.


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## Jim.S (Apr 13, 2020)

Cherryville Chuck said:


> A few years back I built a temporary table that got used for about 6 years. It was a scrap piece of melamine coated particle board maybe a hair bigger than a sink cut out. I wanted to try t tracks for holding the fence in place so that only left 1/4” of material where they were but I added supports under them and that strengthened those sections enough. I laid the sheet onto a ladder style frame with supports close to the cut out for the plate too. Joined the top to the frame with biscuits. It sat in a shed that went from -40 in winter to plus 40C in the summer and was still dead flat after 6 years.
> 
> The short answer is yes it will work. Sometimes a small table is preferable to a large one. A piece with some warp may bridge across a long table but be okay on a shorter table. Lee Valley made a steel table top that had a slight rise to the centre that was there to prevent bridging.


I count this as another vote for the non-conventional torsion-bar approach.

I do have to agree with Stick regarding MDF and of course Particle board.
I have found that Phenolic based plywood is the safest and most expensive approach, sometimes you just have to bite the penny and go for it!

Thank-you very much for your input.


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## Jim.S (Apr 13, 2020)

Cherryville Chuck said:


> I’ve seen a number of posts by people who laminated plywood together and it warped on them. I personally believe it was the glue that did. Glue sets when the water dries. There’s no where for the water to go in the middle of a plywood sandwich but into the plies at the Center of it. That causes the warping I believe. I personally would never do it although some have and been successful. I’ve found no need to since if you attach one layer to a level frame you’ll be fine. Think of the floor under your feet and how it’s built.


I agree with you 100%.
I believe that another underlying cause for warping with glue is some people fail to clamp properly.

Sometimes I spend major amounts of time dry-fitting before I ever touch glue. (wood glue, CNA, Hot glue or any other adhesive).
I often (reluctantly) will use brads or screws to TEMPORARILY hold pieces together until the glues dries.

All in all, think ahead and do everything to avoid warping before the glue hits the wood.

Thank-you so much for your comments, they mean a lot to me.


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## Willji (Feb 28, 2020)

*Torsion box option*

Hi Jim,

I’m in the planning stages with a router table that incorporates an LS positioner, Jessem router lift, and dust collection. So far, my plan is to go with a torsion box assembly. Here is a demo of a torsion box build by Mark Spagnuolo (Wood Whisperer) for an assembly table. 

https://thewoodwhisperer.com/videos/episode-18-assembly-table-torsion-box/

He has a update for one which is thinner.

He uses MDF because it is more dimensionally stable and simply uses but joints for the grid. He has demos that cover making a table organizer under the top.

Hope the above is helpful. I’m researching here as I haven’t made the plunge yet on a design.

Cheers


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## Jim.S (Apr 13, 2020)

Willji said:


> Hi Jim,
> 
> I’m in the planning stages with a router table that incorporates an LS positioner, Jessem router lift, and dust collection. So far, my plan is to go with a torsion box assembly. Here is a demo of a torsion box build by Mark Spagnuolo (Wood Whisperer) for an assembly table.
> 
> ...


Willji - 

I will check out Marks method. He usually has good approaches. However, I am pretty dead set against MDF at this time. I have a lot of money in all of my tools. I believe a little more money in the materials will pay off also. I also have lung issues so I try to avoid cutting MDF inside at all costs.

I am curious to see what his table organization looks like. I hope he doesn't give up on dust collection for organization.

Thanks for your input. I will give it consideration.


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