# Table Saw Crosscut "Cart"



## captfoss (Apr 28, 2012)

Hey all, I was hoping to get some "expert" opinions on a table saw jig that I've been thinking about building. I've scoured the internet looking for a similar concept, but I've yet to be able to find any. I take this to mean I'm either a genius or a complete idiot.

The goal is to build a table saw sled large enough to cut a full 4×8 sheet. Obviously, everyone wants a crosscut sled that'll do that, right?

The major engineering issues, as I see them, are the stress on the extraordinarily long runners (at least 5 or 9 feet, depending which way you're cutting the sheets), the friction of dealing with that much weight in a miter slot, and then keeping the whole thing level. Obviously, you can't build and use a traditional sled this large unless you're the Incredible Hulk.

My idea, then, is essentially a sliding table / crosscut sled hybrid. A basic 2×4 cart that goes "around" your table saw, and has two runners underneath the sled surface that travel along the miter tracks of your saw to keep the cart aligned.

The cart would entirely support the weight, stay aligned with the miter slots, and could essentially make it as large as you need.

Some design drawings (please excuse my horrible SketchUp skills).

Top view:









Bottom view, showing the runners:









Rough estimates of size. These would obviously be tailored to your particular table saw / needs:









Note: I envision the legs having swivel castors rather than locked-angle wheels as depicted (couldn't model castors).

Anyway, I'd love to hear any thoughts you guys have on the concept.


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## Loren (May 30, 2008)

It would interfere with most table saw fence rail systems.

Other than that it's an interesting idea for a dedicated setup
for, say, squaring glued-up table tops.


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## Sawkerf (Dec 31, 2009)

That miter slot alignment could get tricky. If you aren't traveling perfectly straight, you'll probably move the saw. Not something I would want to see. - lol


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## DIYaholic (Jan 28, 2011)

I like the concept, but feel a more complicated, engineered design would be required. As Sawkerf said, alignment is critical. I would also think that it would need to be easily removable. I think a track or guide for the wheels should be employed. I hope you do some further R&D and keep the idea alive.

Good luck.


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## captfoss (Apr 28, 2012)

Yeah, I figure the most difficult part of actually building it would be getting the miters aligned properly, and getting the cart the exact right height.


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## captfoss (Apr 28, 2012)

DIYaholic, I hadn't planned on using T tracks, just rectangular bars. Taking it off would just be a matter of picking it up.


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## jgreiner (Oct 23, 2010)

Hi Captfoss,
Interesting design, I'm pretty good with sketchup, let me see if I can expand your idea a little 

-jeremy


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## jgreiner (Oct 23, 2010)

The design uses 3/4'' plywood and 2×4's I started out with a large table that had 2×4's going around it for bracing. It also uses a ridgid contractor saw as it's reference saw, alot of contractor saws are designed simillairly so I figured this would be a good saw to use for reference. The problem with this design is that there is no room for fence rails and removing the fence to use this jig seems pretty excessive to me. 









I removed the sides added legs wheels etc.. and had it centered on the saw.









This didn't seem good centering on the saw like that, to me it should be as far left as it can go to give you as much support on the left hand side of the cut (like a giant panel sled really).









So I was happy with that design but how do you mount it on the saw.









With this design, I immagine that the right leg is mounted with a hing, and can fold down when folded up there is another locking mechanism of some sort or a bolt that screws it to secure it to the top. This would allow the user to lift the top of the table over the saw and fence and align it with the miter slots. Once the top is down on the table saw, the leg can be lifted up and secured.









To be useful, I'd imagine it would have to be very large. The once designed uses 2 4' by 8' sheets of plywood or mdf for the top, couldn't really go any wider without stitching multiple plywood pieces together which I think would hurt the flatness of the top. From blade to fence it allows a 4' by 8' plywood piece to be cross cut, but you can't rip it along the 8' line (that would require a huge sled). It also has 36'' support to the left of the blade.

While I was happy to design this, I don't think I would ever build something like this, it would take up way too much space. You could try and make it able to be torn down, but you're still looking at storing the 48'' by 79'' table top somewhere (which would also be heavy as hell). I think it's too large and bulky for a home workshop, however if you're doing a lot of cabinets for a large project and just need to cut down a lot of plywood it may be worth build.

I can't attach sketchup files to this thing, if anyone wants it PM me I can email it to ya.

-jeremy


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## Viktor (Jan 15, 2009)

I think it will work. Here is a similar concept:
http://www.woodweb.com/knowledge_base/ShopBuilt_Sliding_Table_Saw_Jig.html


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## davidmicraig (Nov 21, 2009)

I think a sled might be overkill. However, a lift table like the one pictured on this page be very handy me thinks


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## captfoss (Apr 28, 2012)

Jeremy, your sketchup skills are far superior to mine. Thanks for drawing that up.

It's interesting how things get re-engineered based on the target equipment, and funny how sometimes "nicer" equipment is harder to make jigs for. Imagine how big the cart would have to be if you'd designed it around a cabinet saw…

My original design is based on my saw (of course), which isn't a contractor saw with a nice fence system, but a crappy bench top table saw. No fence system *to* remove, so nothing to engineer around.

You hit the nail on the head about this being too big. I'll probably never build this because it'd take up too much room.

Then again, either of these could serve double-duty as a shop cart / mobile workbench given a strong enough top, so maybe someday I can justify it that way.


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## captfoss (Apr 28, 2012)

David,

That lift table cart thing sure looks useful around the shop, but in terms of using it as an infeed table for cutting plywood?

Their illustration looks like a kickback accident waiting to happen. You can stand off to the side like you're supposed to with that cart, but you're limited to cutting plywood into whatever size strips your particular fence system can handle, and I'd imagine you'd have to fight the cart the whole time to keep the sheet from spinning on you.


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## nick85 (Apr 1, 2012)

I've thought about doing something similar in the past, but you would almost need a dedicated table saw for panel ripping, as remounting the fence rails and wings would be a pain in the bootay.

Why not make a vertical panel saw? Much easier to load sheets on to, and should be quite a bit more stable, as the saw is moving over the wood, rather than a wooden cart on casters moving over a shop floor… It would take the same amount of engineering, but takes up less floor space and doesn't require removing parts from the table saw that are already calibrated. Most parts could be made from steel pipe from Home Depot, just make sure that all the pipes are square and run along the vertical supports without binding.


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## intheshop (Aug 18, 2010)

I have a large panel sled and it works fine, although it won't cut a full sheet. And somehow I managed to make it cut perfectly square. An occasional coat of paste wax eliminates the friction issue. Before I discovered this, I nearly tipped my saw over - now it slides like a dream.

However, when I need to cut full sheets, I find it much easier to use my DeWalt Track saw. The Festool saw is excellent as well. And there is an aftermarket straight edge with a carriage for a standard circular saw that works extremely well also.

I've considered something like the cart you describe, but there are a lot of issues you have to get just right.


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## captfoss (Apr 28, 2012)

nick85, whenever I'd read someone mentioning vertical panel saws, I'd always google it and see the 2,000 dollar monsters. It never occurred to me to look up a shop built version.

But apparently there are decent designs floating around for me. If I ever get to the point that I have a shop that doesn't involve have my wife's car parked in the middle of it when not in use, I'll certainly build one of those.


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## nick85 (Apr 1, 2012)

I'd bet one could be built that folds to take up less than 2-3 feet of space from the wall. If I were ripping a lot of plywood, I would put one together, but I am broke and build mainly small stuff. =S I may try my hand at designing one on the computer though, just to test my theories…


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## captfoss (Apr 28, 2012)

If you could design a vertical panel saw that operates like a table saw (you push the wood through it), you should be able to design one that's 4 feet tall and only a few inches wide that would be able to do any possible sheet cut.

I imagine some sort of vertical bracket to hold the saw at an adjustable height, and then maybe some fold down arms that form a track to push the wood though.


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## waho6o9 (May 6, 2011)

I'm glad I didn't purchase a panel saw and purchased Festool instead. Food for thought anyways.


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## Sawkerf (Dec 31, 2009)

captfoss -

The concept of the panel saw (horizontal or vertical) is that you leave the heavy part (the plywood) stationary while you move the light part (the saw). I can't imagine wanting to reverse that. - lol


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## nick85 (Apr 1, 2012)

Exactly. By moving the saw assembly over the wood, you should get a very smooth and straight cut. Moving a 4×8 sheet over the saw, and especially if the base is only a few inches wide, invites curves and binding.


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## canadianchips (Mar 12, 2010)

Good concept. Part of its success will be using good wheels and having a straight smooth floor to roll on. I would consider ripping large panels with it, I am not so sure I would trust it for making dado's


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## Bobmedic (Sep 24, 2010)

Kind of a one trick pony though. A straight edge and a circular saw with a good blade is all I have ever needed. I stack the sheets with the good faces towards the middle four at a time and clamp them flush and break them down. I get great results and I get it done quickly.


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## MrRon (Jul 9, 2009)

Here is some food for thought. Build a table larger than a 4×8 sheet of plywood, say 50"x110". Mount a track on each edge; Construct a gantry that spans the width of the table. Mount a portable saw on the gantry. You would pull the gantry toward you to cut along a X direction. A track mounted on the gantry could guide the saw in a Y direction. This type of saw actually exists and is used in production facilities where large sheets are routinely cut. They even operate along an X and Y axis, so you can rip and crosscut. I don't think it would be too difficult to construct.


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## TartanSailor (Mar 25, 2012)

I hope your floor is dead level ;-)


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## crank49 (Apr 7, 2010)

I could rip a truck load of plywood with my Skil saw and a good guide while you are designing that thing.
Why make it so difficult.


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