Can i use PVC for table saw runners?

[Nick2cd]

i've been thinking about building a cross-cut sled for my table saw and eventually and miter splining jig. anyways, the runners are my current dilema. the hardest, toughest wood i have on hand is cherry. so i started thinking, why can't i buy one of those solid dimensional strips of PVC from lowes and make my runners out of that? i imagine they would be low friction, would not expand/contract, and should be pretty durable. im just wondering if they will hold a screw. what say you, gentlemen?

something like this http://www.lowes.com/pd_238343-99999-282608003_0__?productId=3195345&Ntt=pvc+trim&pl=1&currentURL=%2Fpl__0__s%3FNtt%3Dpvc%2Btrim&facetInfo=

[sbarton22]

interesting. Let us know it you try it. It sounds like a cool idea. I wonder if it bows. The high density plastic that are used as fence guides bow all over the dang place. I suppose if you anchor it that isn't an issue.

I would just question if you are going to lowe's, why not just do it out of MDF?

[Nick2cd]

interesting. Let us know it you try it. It sounds like a cool idea. I wonder if it bows. The high density plastic that are used as fence guides bow all over the dang place. I suppose if you anchor it that isn't an issue.

I would just question if you are going to lowe's, why not just do it out of MDF?

i don't think it'll bow if properly secured with countersunk screws. im thinking of using marc's plan to make the sled, with a possible addition of these PVC runners. i don't really have an answer for "why not MDF"....more stability? i know MDF is stable, but in theory, these runners shouldn't expand or contract at all.

[jhl.verona]

i've been thinking about building a cross-cut sled for my table saw and eventually and miter splining jig. anyways, the runners are my current dilema. the hardest, toughest wood i have on hand is cherry. so i started thinking, why can't i buy one of those solid dimensional strips of PVC from lowes and make my runners out of that? i imagine they would be low friction, would not expand/contract, and should be pretty durable. im just wondering if they will hold a screw. what say you, gentlemen?

something like this http://www.lowes.com...trim&facetInfo=

At the price, I think it's worth experimenting. As for screws, I have my doubts. Most plastics need to be drilled and tapped as you would for a metal, otherwise they deform, can develop cracks, or even chip if they're higher density. If you screw the runner to the sled, you'll only need to drill and countersink, the screw will go into the wooden sled.

HTH

John

[KsSlim]

Use Ultra High Density plastic. Drill through, countersink, and screw UP thru runner into sled.

Works at my house. If you have difficulty finding material, discount store, kitchen area, look for cutting boards made of that material.

[Ben@FineWoodworking]

I think you're on to something here. I'm finding that all of my Mdf jigs are strarting to bow now that there is excess moisture in my from the house duct work sweating.

I'd put an old blade in your saw before cutting it. I used some PVC molding in our dining room and there is still residue on my chop saw.

[Nick2cd]

I'd put an old blade in your saw before cutting it. I used some PVC molding in our dining room and there is still residue on my chop saw.

good to know. i hadn't considered this.

[joestyles]

Teflon works good for that and it slides nicely you can get it from old cutting boards or new one if the wife dont catch ya :)At about 1/2-3/4" thick it is easily milled by a table saw I am not sure what you are talking about with the PVC It is rigid and strikes me it might shatter if it cam into contact with a spinning blade (bad exp with PVC pipe and a miter saw)Never dealt with flat stock though so dont know. I was considering phenolic stuff like for a router table insert as runners I have one that is cracked on one corner and have been considering using it for runners on a sled that stuff is tough and stable was gonna try the band saw to cut it but am waiting for a time when a blade is near the end of its use in case it ruins it. Also the new insert is larger so I have to redo the top of the table first always something else needs doing it seem. Anyhow good luck with the experiment and let us know how things come out pics are nice too

[Onboard]

Nick, as an alternative you could go here and purchase some UHMW Slick Tape (scroll down). Make your runners out of a hardwood like maple, oak or whatever, and apply the Slick Tape which has self-adhesive on one side, to the bottom of the runner. Or, you could buy solid UHMW strips to fit in a standard 3/8” X 3/4” miter slot (same webpage). Or, you might consider using these.

[Nick2cd]

Nick, as an alternative you could go here and purchase some UHMW Slick Tape (scroll down). Make your runners out of a hardwood like maple, oak or whatever, and apply the Slick Tape which has self-adhesive on one side, to the bottom of the runner. Or, you could buy solid UHMW strips to fit in a standard 3/8” X 3/4” miter slot (same webpage). Or, you might consider using these.

i didn't realize peachtree had that high density plastic already cut down to miter slot sizes. that stuff looks pretty good. prices aren't too bad either.

[Beechwood Chip]

Or, you might consider using these.

Incra slide $20 for 24".

Or you might consider this: Aluminum bar stock 3/4" x 5/16" x 72" for $28. You can use woodworking tools on aluminum (but if you use a Sawstop, turn the sensor off).

[BenMinshall]

PVC actually has pretty significant expansion and contraction with temperature. I don't think it would be an ideal material for anything you want to be precise.

edit: To add a little detail, PVC expands at roughly 5x the rate of carbon steel or cast iron and roughly 3x the rate of aluminum for a given change in temperature.

[Nick2cd]

PVC actually has pretty significant expansion and contraction with temperature. I don't think it would be an ideal material for anything you want to be precise.

edit: To add a little detail, PVC expands at roughly 5x the rate of carbon steel or cast iron and roughly 3x the rate of aluminum for a given change in temperature.

wow, i had NO idea this was the case.

[BenMinshall]

Yeah it's pretty staggering when you get into construction sized lengths. For example a 100 foot steel pipe will vary in length about 11/16" between summer and winter whereas a PVC pipe of the same size will vary about 3-1/2" and a CPVC pipe nearly 5". PVC plumbing systems can actually pull themselves apart if exposed to extreme temp swings.

Anyway to bring it back on topic :-) I would probably lean toward the MDF option.

[Beechwood Chip]

Ultra-High Molecular Weight Polyethylene (UHMW) at $2 a foot.

[bois]

I got a free slider when I bought my Incra miter gauge and used it in a spline cutting jig. I was very impressed, it allows you to really fine tune the fit so you get no lateral motion at all, while still being able to slide back and forth with ease. This can be difficult or impossible to achieve with wood (and potentially plastics). Yes, they do cost $30 but how much stock will you ultimately waste when your sled racks or sticks?

Incra Steel Miter Slider

[Jesse]

I've been making mine from bamboo flooring scraps. Bamboo is super hard, super stable, and I've found it to machine excellently.

I recently had to make a longer sled (7') for edge jointing, really long miters, tapers, etc, and I didn't have long enough pieces of bamboo. I used poplar on this with no problems.

Concerning PVC, I know that vinyl shrinks and expands with temperature, not humidity. Not sure if this will show any effect in something as small as a runner, but its still good to keep in mind.

[jHop]

If you're headed up to a big box retail store, skip the PVC and go to the moulding sections. Look for the pre made square mouldings, and use that instead. A little trimming with sand paper should be all that's needed.

otherwise, I'd consider the UHMW stuff, or the slickstrip stickers, or the poplar. I'm hesitant to put aluminum into the miter slots, more because of metal on metal rubbing. If i went with the metal sliders, I'd definitely coat it or cover it with the slick strips. Less likely of the metal widening the miter slot that way.

[CaptRandy]

I actually found a piece of aluminum from a wall shelf unit that was the exact size to fit the groove and used that for my sled.

[Redeft]

I got lucky, where i work we have large nylon cutting boards those cut to fit work great with no fricton.

[ChetlovesMer]

Making sleds from plastic cutting boards (purchased at the dollar store... good idea, KsSlim) is cheap and fun. Plus you cam make them in different colors. I have a few I've made for different tasks. Hang them on the wall of your shop and people will ask you about them.

I cut them on my SawStop and it did not set off the blade protection device, but you may want to check yours before you run it. I always do a quick and careful little test when ever I run anything that's not just wood. ... 2 one dollar cutting boards, plus 1 sixty dollar break equals 1 sixty two dollar sled.

[Nick2cd]

Making sleds from plastic cutting boards (purchased at the dollar store... good idea, KsSlim) is cheap and fun. Plus you cam make them in different colors. I have a few I've made for different tasks. Hang them on the wall of your shop and people will ask you about them.

I cut them on my SawStop and it did not set off the blade protection device, but you may want to check yours before you run it. I always do a quick and careful little test when ever I run anything that's not just wood. ... 2 one dollar cutting boards, plus 1 sixty dollar break equals 1 sixty two dollar sled.

So Chet,

Are u making the entire sled out of the plastic board or just the runners? How bout some pics, please?