# Cross Cut Sled



## scott lindsay (Jun 22, 2010)

I am making a cross cut sled so I can make shelves to go into a mobile cabinet I am making. I got some plastic UHMW runners from WoodCraft and they are just a hair tight. I do not want to file the cast iron slots of my table saw so I just want to reduce the with by may be .010". I have tried using coarse grit sandpaper but that is not doing it, or at least it is not going as fast as I would like. Any suggestions? Maybe stop fooling around with these plastic runners and get some 1 X 1 Maple strips from Lowes or Home Depot? I am open to suggestions. Am the cross cut sled, I would like to make a couple of other table saw jigs but they too will need runners. Keep in mind my shop is limited on power tools, no band saw and no router table, no planer or jointer.


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## TomCT2 (May 16, 2014)

UHMW you will have to use a sharp scraper.

do you have groves in the sled? I mounted the slides in the sled groove then started scraping at one end, advancing the scraping little by little as the slide fit the table. scrape only one side....


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## Maylar (Sep 3, 2013)

A block plane would shave them too.

I used 3/8 x 3/4 steel bar stock for mine.


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## Larry42 (Jan 10, 2014)

A hand plane like stated above will work fine.


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## GeorgeC (Jul 30, 2008)

I just used oak that I cut on my table saw to the correct size.

George


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## Tool Agnostic (Aug 13, 2017)

GeorgeC said:


> I just used oak that I cut on my table saw to the correct size.


George is right. 

I am about to build my own crosscut sled. Take any advice from me with a grain of salt, because I am a novice. Still, I have been doing a lot of book and internet research about crosscut sleds, among many other things. Despite my lack of experience, I know what I intend to do when I build my sled in the near future, so I will share my plans with you:

* Use the table saw to cut strips of scrap wood for the miter slots. 
* The strips of wood should fit in the miter slots of the table saw. There should be no side-to-side wiggle or play, but the strips should slide back and forth smoothly in the slots.
* When the strips are in the miter slots, the tops of the strips must be below the height of the table saw's table. 
* Remove the strips and insert identical coins along the bottom of the miter slots. Place the wood strips on top of the coins. With the coins in place, the strips should protrude evenly above the height of the table saw table.
* Brush a thin layer of glue on the top of the strips. 
* This is the tricky part: Use a square to position the crosscut sled so that it is a perfectly aligned with the miter slots. You want it to make perfect 90 degree cuts. 
* Place weights on the crosscut sled and leave them in place until the glue cures and dries.
* Remove the coins from the miter slots and start using the sled.


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## scott lindsay (Jun 22, 2010)

TomCT2 said:


> UHMW you will have to use a sharp scraper.
> 
> do you have groves in the sled? I mounted the slides in the sled groove then started scraping at one end, advancing the scraping little by little as the slide fit the table. scrape only one side....


TomCT, No grooves in the sled part.


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## TomCT2 (May 16, 2014)

Scott - having it mounted in a groove makes it stiffer - otherwise it may tend to bow under pressure and that really complicates a scraping process.

alternately you could use set screws - 10-24 x 5/8 length is the usual size (get 24 count thread for plastics; the alternative 32 thread is so fine it often strips out...) in a soft plastic you can usually get away without tapping the hole but you'll need a set of numbered twist drills to get the proper 'fit'

use a oval/round pointed set screw (not a 'cup end' type) or if you can find them in that size, a plastic tipped end. you can tweak the set screws absolutely perfect for the width. don't be surprised to find the miter slot width varies a smidge along it's length . . . . 6-8" spacing between set screws eliminates wiggle due to the width variations.

Tool Agnostic: plastics are my preferred material because wood swells/shrinks with humidity - which makes their sliding effort vary from loose to 'it's stuck and can't get up' - I use scraps from solid surface counter tops aka Corian - it will take hand sanding with fine paper without the fuzz....


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## Tool Agnostic (Aug 13, 2017)

TomCT2 said:


> [...]Tool Agnostic: plastics are my preferred material because wood swells/shrinks with humidity - which makes their sliding effort vary from loose to 'it's stuck and can't get up' - I use scraps from solid surface counter tops aka Corian - it will take hand sanding with fine paper without the fuzz....


I get it, but it seems like a lot of trouble for a couple of guide rails. Still, your plastic/Corian would be better than wood. 

I note that many people are using scrap wood for crosscut sled rails, and it works for them. Some have used plywood. 

The authors of several books I recently read all suggested wood rails in their designs. There may be temperature/humidity expansion and contraction effects on the wood rails, but I suspect that it is not as much of a problem (for crosscut sled rails) as was implied. 

P.S. I remember now that some people use hex nuts instead of coins in the bottom of the miter slots to raise the rails for alignment and attachment. They are size consistent and somewhat higher than coins.


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## scott lindsay (Jun 22, 2010)

I took a small hand plane to them yesterday and it did the trick. They seem to work. I only needed just a few .001" of an inch off. Now I need to attach the backstops and make them perpendicular to the saw cut. First, this might be a good time to tune up the table saw and make sure everything is square and true or this exercise will be just an exercise.

First, my RC Airplanes come first. Working with Balsa Wood and really thin plywood can be challenging.

-Scott


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## GeorgeC (Jul 30, 2008)

scott lindsay said:


> I took a small hand plane to them yesterday and it did the trick. They seem to work. I only needed just a few .001" of an inch off. Now I need to attach the backstops and make them perpendicular to the saw cut. First, this might be a good time to tune up the table saw and make sure everything is square and true or this exercise will be just an exercise.
> 
> First, my RC Airplanes come first. Working with Balsa Wood and really thin plywood can be challenging.
> 
> -Scott


The sled runners will be parallel to the saw blade. Not perpendicular.

George


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## TomCT2 (May 16, 2014)

I attach the mitre slot rail to the sled - the sled flat is oversized. then I cut the sled using the rail&slot&sawblade. bingo - instant parallel edge. 

for the sled backstop, I use a carpenter's square which I've double checked for 90' accuracy to mount the backstop perpendicular to the instant parallel edge - double checking by sliding the square+backstop+sled past a single stationary tooth on the saw blade.

many other methods and madness exist to set-up sleds - some work, some don't, some are grossly inaccurate.


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## scott lindsay (Jun 22, 2010)

GeorgeC said:


> The sled runners will be parallel to the saw blade. Not perpendicular.
> 
> George


The backstop and the front fence are perpendicular to the blade. Yes, the sled runners are parallel to the blade. 

I tried making my sled again. I put the plastic UHMW runners and used a hand plane. They slide very nice in the slot. I used double sided tape and screwed them in place. Now it fits in the tablesaw groove but only slides a little of the way until it binds. I took them off and planed them again, and re-installed. The sled still binds up. It is not easy to plane them because I have little material to hold on to it. 

I tried to cut a 1/2" runner from plywood. Now the runners are to tall. If I had a joiner or a planer this probably would not be an issue. Does anyone had any suggestions? I am so new to this I have no idea how to even choose lumber from Home Depot.


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## Toolman50 (Mar 22, 2015)

scott67 said:


> The backstop and the front fence are perpendicular to the blade. Yes, the sled runners are parallel to the blade.
> 
> I tried making my sled again. I put the plastic UHMW runners and used a hand plane. They slide very nice in the slot. I used double sided tape and screwed them in place. Now it fits in the tablesaw groove but only slides a little of the way until it binds. I took them off and planed them again, and re-installed. The sled still binds up. It is not easy to plane them because I have little material to hold on to it.
> 
> I tried to cut a 1/2" runner from plywood. Now the runners are to tall. If I had a joiner or a planer this probably would not be an issue. Does anyone had any suggestions? I am so new to this I have no idea how to even choose lumber from Home Depot.


If you hade the runners sliding nicely in the grooves and found it binds when screwed into place, you did not keep the runners square when you attached them to the sled. If they were fine prior to attachment, then something failed when you attached.


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## scott lindsay (Jun 22, 2010)

Toolman50 said:


> If you hade the runners sliding nicely in the grooves and found it binds when screwed into place, you did not keep the runners square when you attached them to the sled. If they were fine prior to attachment, then something failed when you attached.


I agree with you that something failed. Since I am using the UHMW plastic, I think one of two things happened. 1) Even though I used double side tape to hold in place, the plastic is flexible so it shifts as you screw it in place. 2) If you do not use a clearance hole, as you screw into the plastic, the plastic has a tendancy to bow slightly at each screw placement causing the runner to grow in width.


I went out last night and took my hand plane again to the runner. I got the sled to slide easily. It does not bind so much now. I was going to make the front and back fence however looking at the 3/4" plywood I have and it has a slight bow to it. I thought about going to Home Depot and getting MDF but screwing into the ends of the sheet does not always go well. So, how do I take out a bow in the plywood so that the front fence is nice and flat for lining up the boards. I estimate that I cannot afford a planer until October (saving a little from my paycheck each week).


Also, I watch a You Tube video where someone put wax and some type of other conditioner (not the term used in the video) on the bottom of the sled to slide easier. The video was 3x3 Company - Tamara. I like the t-slots she made in here sled. I used 1/2" plywood for my sled, I think she used 3/4".


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## Larry42 (Jan 10, 2014)

Plywood is often "non-flat" but that probably won't cause much of an issue if it is just a little off. I've made two sleds. The first just used hardwood runners and lasted a long time. Just keep them waxed and there will be vey little wear and the amount of width change with varying humidity is very slight on a 3/4" width. My 2nd one had UHMW runners. Even though I fit them accurately and pilot drilled the screws, the screws still expanded the plastic a bit. I had a rabbet plane so it was quick and easy to just take a bit off by each screw. A sharp cabinet scraper probably works just fine also. I used melamine coated MDF for the 2nd one, kind of heavy but stayed flat. I used melamine glue and only a few screws to hold the fence on. On my first one I didn't make the piece that keeps the far end of the board together heavy enough and it broke after a few weeks of use. Easily fixed but should have known better. Make yourself a nice shooting board. Screw a couple of toggle clamps to it and you can easily make perfect edges for glue-ups or just nicely finished clean edges. You can make a 45 on the end for miters. Get yourself a sturdy bench and vices. If you don't want to make a traditional woodworking bench you can just drill a few holes for spring type clamps that you just give a hit with your mallet to hold and tap up to release. It always takes two to hold. I suspect Woodcraft or Garret Wade has them. On the subject of mallets, I made a round one from a piece of Osage and it has lasted many years. The nice thing about round ones, they tell your hand how to adjust with each hit. That way you can watch the sharp end of the chisel all the time. Never a hit finger.


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## scott lindsay (Jun 22, 2010)

Larry42 said:


> Plywood is often "non-flat" but that probably won't cause much of an issue if it is just a little off. I've made two sleds. The first just used hardwood runners and lasted a long time. Just keep them waxed and there will be vey little wear and the amount of width change with varying humidity is very slight on a 3/4" width. My 2nd one had UHMW runners. Even though I fit them accurately and pilot drilled the screws, the screws still expanded the plastic a bit. I had a rabbet plane so it was quick and easy to just take a bit off by each screw. A sharp cabinet scraper probably works just fine also. I used melamine coated MDF for the 2nd one, kind of heavy but stayed flat. I used melamine glue and only a few screws to hold the fence on. On my first one I didn't make the piece that keeps the far end of the board together heavy enough and it broke after a few weeks of use. Easily fixed but should have known better.


Larry42: I am not worried about the bow being on the plywood sled base. The bow I am concerned about is the front fence where piece rest against to give a nice 90° cut. A bow would not give a nice 90° cut. I was going to glue up two 3/4" plywood 20"x5" as my fence. Now I just do not know what to use to get a flat surface. I do not have any hand planes yet nor a power planer and I did ask a local cabinet maker if he would plane some boards in his off hours but he said no. I just need to keep thinking out side the box...maybe a nice piece of angle aluminum?


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## ORBlackFZ1 (Dec 25, 2013)

*Hardwood runners with JPW (Johnson Paste Wax)*



scott67 said:


> Larry42: I am not worried about the bow being on the plywood sled base. The bow I am concerned about is the front fence where piece rest against to give a nice 90° cut. A bow would not give a nice 90° cut. I was going to glue up two 3/4" plywood 20"x5" as my fence. Now I just do not know what to use to get a flat surface. I do not have any hand planes yet nor a power planer and I did ask a local cabinet maker if he would plane some boards in his off hours but he said no. I just need to keep thinking out side the box...maybe a nice piece of angle aluminum?


Assuming your table saw top is flat....I would suggest that you put down a sheet of plastic (to protect the table top from glue) and glue up two 1/2" x 5" x 20" pieces of plywood for your fence. Make sure that you clamp the glue up to the table top. 

Most table saw tops are not flat on the bottom, so before you start the glue up, clamp a long board on the bottom of your table saw top to use for clamping.

You should find that if you orient the two pieces of plywood together correctly, the gluing process plus clamping to a flat surface will remove the bow in the plywood. The correct orientation is to have the long ends touching and the center open when you just hold the plywood together.

As for runners, I do not use UHMW material for runners due to the reasons you have found. I use a hardwood such as maple or oak for all of my runners. I have never found the wood changed enough to make any difference during summer or winter (I live in the Portland, Oregon area and my woodshop is NOT heated). Most of my runners have a good coat of JPW (Johnson Paste Wax) on them which keeps them from having any noticeable change from season to season.

Eric


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## allpurpose (Mar 24, 2016)

The good part of the very term wood scraps is the term wood scraps. They're cheap and easy to replace. 
A cross cut sled isn't the most complex piece of equipment you'll ever make. A chunk of plywood, a few pieces of 3/8" x 3/4" hardwood and a few pieces of wood for the fence is pretty much all you need and a few screws.. You really don't need state of the art high dollar materials to make a decent cross cut sled.. Unless you live in a shed right on the beach during the rainy season the amount of swelling and shrinkage aren't going to make or break you I would hope..


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## Larry42 (Jan 10, 2014)

Scott, The base material, ply, mdf ... Will keep the fence from changing shape, just glue and screw it on @ 90 to the saw's fence. Easy done with a framing square. The opposite end bridge piece will hold the two parts of the base together and keep them "square."
Don't over think this!


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