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Chuck Pickering
01-09-2017, 2:35 PM
I'm getting ready to build some jigs and sleds for my table saw. I have been reviewing forums and videos on various jigs and makers designs. I understand why UHMW and HDE are recommended over wood for runners for jigs. My question is, wouldn't a poly finish and a good application of paste wax prevent wood runners from absorbing moisture and expanding?
I found a stash of what I think is hickory(it's quite dense, hard and straight grained) in the rafters of my garage left by the previous owner, that I am going to try making sled runners from.

Chuck

glenn bradley
01-09-2017, 2:43 PM
Geographically variable I would imagine. In my narrow humidity swing desert basin I have used straight grained white oak and ash both with success equal to UHMW and Aluminum (which I also run). The hardwoods with a bit of paste wax are just as slippery as the UHMW material. Keeping the jig base and tool top waxed is just as important.

Jamie Buxton
01-09-2017, 9:26 PM
This is one of those issues where the majority of the advice on the web is wrong. Expansion and contraction of a piece of wood that is only 3/4" wide is only a fraction of a thousandth of an inch. That is, you can run a single wood runner without any issue. Where people get in trouble is that they put two runners on their sled. If you do that, now you have to consider the expansion and contraction of the sled material over the distance between the two runners -- fifteen inches or so. For almost all considerations, plywood can be said to not expand or contract. But over the 15", a teensy percentage expansion might turn into several thousandths of an inch, which might be enough to make the slide sticky. The fix is to put only one runner on your jig. Make it from wood if you like.

Bruce Wrenn
01-09-2017, 9:56 PM
1018 cold rolled steel is my first choice. Exactly 3/4" wide. Last piece I bought (several years back) was $36 for a 12' length. Bought it from local steel distributor. MSC, McMaster Carr and others sell it in 6' lengths. Only with free shipping is it a better deal for me than local distributor.

Wayne Jolly
01-10-2017, 2:18 PM
I stopped using anything except aluminum a few years ago when I was at my local metal supplier buying steel for something else. I happened to see some AL flat bar and the price was very reasonable so I bought a 20' piece.


Wayne

Doug Garson
01-10-2017, 6:05 PM
I've used leftover engineered hardwood floor material for sled runners with success. They're basically plywood.

Chuck Pickering
01-11-2017, 4:57 PM
I've used leftover engineered hardwood floor material for sled runners with success. They're basically plywood.

Thanks, Doug. Happen to have a few pieces of that.
Going to try a zero clearance insert from it as well.
Also remembered to check for HDPE cutting boards in Walmart while I was there today picking up a few groceries.
Went to Lowes and picked up double stick tape, a forstner bit and a Kobalt SpeedFit countersink/drill and driver tool with a set of replacement bits. A sled building we will go...

Chuck

Doug Garson
01-12-2017, 2:42 PM
Great minds think alike :D, I've made zero clearance inserts from it too. Maybe we should have a thread on reusing leftover engineered hardwood!

Chuck Pickering
01-12-2017, 7:27 PM
I'll go for that, Doug, except I was pretty good with my math(read tight arsed and narrow budget) when I ordered the flooring for my kitchen/dining room makeover. I only have a few scraps left! Still, if I was to check with the big box stores and the small guy flooring shops, I bet I could come up with some damaged goods to use for projects!

Chuck

Doug Garson
01-12-2017, 9:29 PM
I have 2 1/2 boxes of leftovers. We had 1 box and a partial box left over 3 years ago when we initially installed the floor. The restocking fee was more than the cost of a box so we kept it then last year we had a flood and the floor was replaced by insurance and we had another box and partial box leftover. So far in addition to sled runners and zci's I've made a computer cabinet and shelf for a bakers rack from some of the leftovers.

Richard Dooling
01-13-2017, 4:59 PM
+1 on Jamie's recommendation to just use one runner for most sleds.

I also have a cut off sled with one narrow runner. I push the sled to the right for the cut, slide to the left and draw the sled back without further engaging the blade. I use this for final trimming cuts on modest size pieces with usually no scrap to the right that would impact the blade.

Tom Lathrop
01-16-2017, 10:02 PM
Certainly a stable high density wood will work as will a single runner on a sled but, if done very carefully, twin runners of synthetic material will be better. I used some 3/8" phenol fiber that I happen to have and cut it in multiple passes to creep up on the exact width. Then press the runners into the slots sandwiched with one mill plastic and double face tape the sled on top of that before screwing it down. This is, by far, the most friction free and accurate sled of those I've made. Wax is always a good thing too.