# Cross cut sled runner materials



## groland (Jan 21, 2009)

I write in search of comments from users regarding materials for crosscut saw sled runners. I have made several crosscut sleds for various purposes and have always made my own runners out of red oak. My shop is in an unheated garage where temperature and humidity fluctuate a good deal. This condition along with wooden runners simply wearing out prompts me to seek advice of other runner materials that might be more stable and wear better.
I see Incra makes aluminum Miter Slider runners and also some steel ones. There is also a plastic material UHMW plastic said to be suitable. The UHMW is claimed to be "machineable", but I don't know exactly what that means-can I cut it with a table saw, run it through my thickness planer etc. or does it require carbide edges to mill it properly? The Incras have a range of adjustments for miter slots that aren't quite .75 inches, which is appealing, but, of course, anything adjustable can come out of adjustment.
Any comments regarding these materials or suggestions for other materials to consider?

Thanks,

George Roland


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## Kazooman (Jan 20, 2013)

I also used to make runners out of wood and always ran into problems down the road as you did. I finally purchased a couple of metal runners that can be adjusted for a good fit in the groove. They come with pre-drilled and countersunk holes for mounting screws. After several years of use they still make a good fit and have never needed adjustment.

I got mine at Woodcraft. They are the Glide Lock brand.


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## kimballd (Jul 27, 2013)

I usually use scrap Ipe. It's very hard and stable. Also, Harbor freight has plastic cutting boards made from what seems to be UHMW. The are $2 bucks. Used that once with good results.

Kimball


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## bbasiaga (Dec 8, 2012)

I made my last runners out of UHMW. It cuts just fine on your table saw or band saw. I have never tried to run it through my planer, though now you made me curious. Easy to work and dimensionally stable. Holds a screw fine.

Brian


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## Cooler (Feb 3, 2016)

Try using a plastic cutting board. Cut it to strips. Good lubricity and no swelling. Sam's club sells really large ones for a very low price.


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## TheFridge (May 1, 2014)

Cutting boards are probably LDPE. It'll work.

I've cut, planed, hand planed, and jointed UHMW polyethylene. Will do zero damage to tools.

If your wooden runner swell just point a fan at them for half an hour.


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## MrUnix (May 18, 2012)

Most cutting boards I've seen are PE - LDPE, HDPE or UHMW. The only problem I've heard regarding plastic ones is that they will bulge where the screw attaches it if you aren't careful. I've used red oak without any problems, usually with a couple coats of wipe on poly and then waxed. Mine live in an unfinished garage as well, with some pretty wild humidity changes, and they haven't been a problem yet. I've also read where people have used those metal shelf bracket strips. I'm getting ready to make another sled as well, and I'll probably experiment with some HDPE since it's free and I got a bunch of it (milk jugs 

As for the workability of PE, it's mostly just like wood - except it has a tendency to melt if cut too fast. For cutting it (LDPE/HDPE in particular) on the table saw, I usually slow down the motor to somewhere between 1/2 and 3/4 full speed, so it reduces the chance of that happening. Ditto on the scroll saw. Running it through the planer is way cool as it shoots out really long curly-cues. And it turns really easily on the lathe.

Cheers,
Brad


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## MrRon (Jul 9, 2009)

I've heard of runners being made from Baltic birch plywood that stays stable with changes in humidity. Another material that works well is phenolic.


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## Rentvent (Jan 28, 2016)

IKEA is also a good source for cheap cutting boards.


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## DrDirt (Feb 26, 2008)

The plastic works - 
Just be careful when you countersink the screws, it sometimes will "bulge" the sides of the runners and cause them to bind.
No biggie - you either 
(1) 'back off the torque" a smidge.

(2)Countersink a 'pan head' screw that won't act as a wedge in the hole
or
(3) use a scraper and shave the runner right next to the screws.

I use hardwood runners. I used hard maple on my current sled, oak on the predecessor.
Arrange the strips to be 'quartersawn" where the grain runs vertical in the groove.


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## pintodeluxe (Sep 12, 2010)

I use adjustable commercial jig runners made from metal. You will use a crosscut sled for a long time, so you might as well get components that will be accurate over the long haul. Crosscut sleds need extra long runners for best results.


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## DirtyMike (Dec 6, 2015)

How awesome , I am currently waiting for the glue to dry my runners to my sled. I used some 3/4 maple flooring leftover from my floors as it was already a perfect fit. I will go with cutting board material for my big sled.


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## Redoak49 (Dec 15, 2012)

I use the Incra miter sliders as they work very well and adjustable.

When a sled gets old or chewed up, I take them off and put on a new sled.


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## maverik (Dec 30, 2015)

I used to use wood runners but they wore out to soon and got sloppy, recently I've had good luck with metal runners


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## lew (Feb 13, 2008)

steel bars. really inexpensive. never swell. little wear. re-usable. Borg. Fastenall. Welding shops. Machine shops.


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## BurlyBob (Mar 13, 2012)

Yeah, I'm going follow Lew's lead…Metal.


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## ddockstader (Jun 21, 2009)

One last option you might consider. I was building a jig for the table saw and the guy who built the original recommended buying some of the plastic wood that the big box stores sell. It's generally for painted molding around the house, but you can buy a 1" x 3" x 8' for really cheap and it makes really nice runners. I've had the oak runners and the UHMW runners, but for quick cheap runners, this stuff works very well.


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## OggieOglethorpe (Aug 15, 2012)

I LOVE 1/4" BB plywood…

Orient the center ply so you're looking at end grain. Birch end grain is remarkably tough, and wax burnishes in with use, it's super stable, and really easy to install.

Make one cabinet, and you'll probably have a lifetime supply of stock for free… :^) Rip a bunch of strips slightly oversize and gang plane them on edge 'till they press fit into your saw's slots. Toss 'em on a shelf and you can whip up specialty jigs in minutes. You probably won't ever have to make more.

I learned this from a long-time North Bennet Street School instructor, and many New England schools and pro shops use BB ply runners, they last for years in constant use. If you take a close look, you'll notice there's no reason to ever make runners deeper than 1/4", due to the washer slot.

Have fun!


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## oldnovice (Mar 7, 2009)

I use UHMW and steel runners.
I bought some precision ground 3/4" stock and worked it until it fit the grooves.
I blue them to reduce the rusting.
I also use tye UHMW because it is temperature stable and can be machined easily.
The UHMW is very good for short runners as can add a little bow when mounting them and reduce play.


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## xeddog (Mar 2, 2010)

Aluminum bar stock


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## splintergroup (Jan 20, 2015)

Several times I have posted my gripes on the 'adjustable' miter bars. My early 2000's vintage Unisaw has the typical over width miter slots. Most of the aftermarket adjustable bars are designed to fit well into undersized slots (like some older Craftsman saws), and then adjust to fill wider slots. The problem is with the adjustments being so far out for my situation, it becomes critical how the adjustment is done. My Incra miter gauge is a fantastic device, but the expanding nylon 'buttons' to take up the slop just really suck. I ended up drilling, threading, and installing 6 roller spring tipped set screws to take up the slop.

For my sleds, I've used two methods. The crosscut sled uses both miter slots so I used commercial aluminum runners (Rockler) and forced them to ride on opposite sides in their corresponding slots. This takes up all slop, works smoothly, and there is joy in my world. 
For my single runner panel sled, I use a 1/4 sawn strip of oak. I get a tight fit (since I can cut it to the size I need), but it does wear.

In desperation, my replacement will be two parallel steel bars, 3/8" x 3/8". Since my slot is 0.009 over 0.750, I can add shims between the bars to get the spacing I need (and protect the shims from wear). If I had a mill, I'd cut down some 7/8" bar to size.

My impression is anything that is softer than the Iron tabletop will eventually need to be replaced or adjusted, I'm beginning to prefer metal that does not need adjusting.


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## HokieKen (Apr 14, 2015)

If you're using a runner in both miter slots, hardwood is fine. Just cut them undersized and make the sled so the runners only contact the inside edges of the slots. That fully constrains the sled and also leaves the runners room for expansion.

HDPE/LDPE/UHMW are good choices but, as noted above, the material will bulge where screws are located so make sure to file/sand/cut those bulges down.

One note on metal runners… metal is obviously the superior choice, no noticeable expansion/contraction, stable and not wearing. BUT, make sure your runners are softer than your saw table. Something is going to wear if you have a tight fit. Better that an aluminum runner wears a little over time than a steel runner causes your miter slots to wear. Go with aluminum or mild steel if you go that route.


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## Cooler (Feb 3, 2016)

> If you re using a runner in both miter slots, hardwood is fine. Just cut them undersized and make the sled so the runners only contact the inside edges of the slots. That fully constrains the sled and also leaves the runners room for expansion.
> 
> HDPE/LDPE/UHMW are good choices but, as noted above, the material will bulge where screws are located so make sure to file/sand/cut those bulges down.
> 
> ...


Someone mentioned earlier to use flat head screws. Countersink with a small forstner bit so it is flat too. No bulge will occur.

Indeed this is a good tactic to use when screwing down easily split wood. A V-shaped countersink is not good for for that either.


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## oldnovice (Mar 7, 2009)

Be aware, aluminum on steel has a fairly high coefficient of static friction and a higher, almost 3X, thermal expansion coefficient than steel.


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## dschlic1 (Jan 3, 2013)

I use UHMW, cut to fit the miter slots in my table saw. I have not had a problem with screws bulging the material, UHMW is fairly stiff material. It is also extremely wear resistant, used in industrial settings for rub plates. It is however flexible, so I cut a shallow groove on the bottom of the sled, and mounted the runner in that slot, eliminated all possibility of flexing. McMaster-Carr sells 3/8" thick UHMW in four foot long sheets.


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## Dwain (Nov 1, 2007)

I have done many things, plywood, hard wood, plastic and metal. I bought some aluminum and made some runners out of that. It has worked really well.

Honestly, i find I can spend my $16.99 on other things than fancy guide runners. That being said, if you don't wan to put up with the issues, you can buy them. When I made my aluminum runners I had to countersink but with aluminum it isn't a big deal. Steel isn't either if you take your time and use the right tools.

The matter is simple, but the commercial runners if you don't want any issues, Buy metal or plastic if you want fewer issues. Just remember to wax the living heck out of it.

My two cents…


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## Cooler (Feb 3, 2016)

> I have done many things, plywood, hard wood, plastic and metal. I bought some aluminum and made some runners out of that. It has worked really well.
> 
> Honestly, i find I can spend my $16.99 on other things than fancy guide runners. That being said, if you don t wan to put up with the issues, you can buy them. When I made my aluminum runners I had to countersink but with aluminum it isn t a big deal. Steel isn t either if you take your time and use the right tools.
> 
> ...


All the aluminum runners I've see have been anodized. Anodizing substantially hardens the surface of aluminum an makes it a fairly hard wearing material.

Race car versions of production engines do not have the cast iron liners for wear resistance. They use hard anodizing instead. It is hard enough to last 500 miles and they have fewer issues with expansion and contraction without the cast iron liners.

Anodizing is a penetrating finish. When you look at the surface of an anodized piece you are looking at aluminum. The longer the part is left in the anodizing bath the deeper the penetration and the harder the surface.

All of which is to say any experience you have with mill finish aluminum (the stuff you see in the big box stores) will not resemble the experience with anodized aluminum.


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## rick1955 (Jun 26, 2014)

Cutting boards are made of hdpe not uhmw. Hdpe is a good choice for sled runners. A lot cheaper than Uhmw plus you can get the cutting boards at Walmart.


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## Cooler (Feb 3, 2016)

> Cutting boards are made of hdpe not uhmw. Hdpe is a good choice for sled runners. A lot cheaper than Uhmw plus you can get the cutting boards at Walmart.
> 
> - rick1955


That was my point in suggesting it. I buy them from Sam's Club where they sell commercial grade cutting boards which are much thicker (about 1/2" thick) and much larger (about 15" x 20") and cost $16.00 for two. For those with math challenges that is $8.00 each. I find that the 20" length is a better for some runners.


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## TajBuilder (Aug 6, 2008)

I've used UHMW plastic to build everything from riser blocks for my lathe to runners for jigs and sleds. Its very easy to machine but will melt when cutting thick pieces like when I made my riser blocks on a table saw. I made them 1/8" oversize so I could trim 1/16" off each edge for a good finish cut. The saw marks sanded out with 100 grit sandpaper on a ROS. I also made a transom saver for my boat to mount transducers.


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## groland (Jan 21, 2009)

Thank you!! to all responders. What a wonderful collection of experiences! I greatly appreciate your contributions.
I live a good two-hour drive from the nearest Woodcrafters and drove there last Friday to pick up some baltic birch plywood for my crosscut sled and some other jigs.

One of my purposes was to look at the available materials for runners, and I ended up purchasing three products-a set of 30" Kreg aluminum guides, a couple of Incra steel ones that are shorter and a sheet of the HDPE material, so now, I am going to try them all out. Should be fun.

I am going to begin with the Kreg runners to make a pretty sizeable sled, since they are long enough to fit the dimensions with which I plan to work. I have already fitted them into my saw's miter slots, adjusted for a smooth solid fit. Just need to make the sled now.

I anticipate better results than I have had so far with my earlier wooden runners.

Cheers,

George


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## leslie88 (Apr 16, 2014)

I use shopfox t-track. https://www.amazon.com/Shop-Fox-D2725-36-Inch-T-Slot/dp/B0000DD1O9/ref=sr_1_1?ie=UTF8&qid=1474916119&sr=8-1&keywords=t+track. It fits perfectly well on my craftsman 22124 saw.


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## Lazyman (Aug 8, 2014)

I usually use hard maple for mine and I have had no problem as long as I remember to apply paste wax every few months.  I bought a strip of UMHW specifically designed to fit standard miter slots on Amazon last year when it was reduced but it is still sitting in the corner because the maple ones I made are still working fine.


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## shankapotamous (Jan 14, 2019)

Bringing back the dead here.. but I used some maple and I live in FL. They were fine right after cutting them just a week ago. Now it's slightly cold and they have shrunk down causing quite a bit of movement. I bought Microjig brand slides but I guess my measurements were off cause they bound up on me as soon as I drilled them in. Talk about frustrating stuff. I'm wondering now if these wooden slides are still the way to go or if I should go to some plastic ones with super glue and then some screws?


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