runners for crosscut tablesaw sled

[Halo Jones]

This is a stupid newbie question but I cannot puzzle which way is best:

I have a length of quarter sawn oak I want to use to make the runners for a table saw sled. Which way do I want to insert the wood to minimise the expansion and contraction? Growth rings running vertical or horizontal?

Cheers,

H.

 

[Chrispy]

Wood tends to move more in the direction of the annual rings that accross so virtical, but on such a small section I really wouldn't worry either way.

 

[Steve Maskery]

+1
Vertical, but on such a small piece, it's unlikely to make a lot of difference if the wood is properly seasoned first.

A word of caution. If your saw is cast iron, don't leave the sled on when you are not using it. The oak runners will rust the slot. DAMHIKT. Maple is a good choice, or beech if you can keep it straight enough.

 

[Wood Monkey]

I spent a couple of hours this very weekend making a new mitre sled for my Scheppach TS2500Ci. The slots and the standard runners that come with the saw are so appalling - nearly 2mm of movement.

I've made several now, a couple of fixed 90 degree sleds and a couple of 45 degree mitre sleds. I've used Oak, Beech and this weekend I even used a piece of Ash as it was nice and straight. I've never had any issues with the runners expanding.

I make my sleds with double runners, i.e. one for each slot on a single sled. I make them to rough dimension, usually a little over sized, and then fine tune with sand paper. Once they fit nicely (I always make them a little tight) I then slide them in the slots, overlay the sled on the top and drill through and screw them to the sled. Pull it out, wipe on lots of beeswax and slide it in and out for a minute or so and voila.

The Scheppach slots are T shaped so a little more fiddly but still only take me 30 minutes or so to make a pair. Standard (decent) 3/4 slots will be a breeze. It's really worth doing because there is zero movement and they cut beautifully accurate over and over again.

I'll try and pop out and take a few snaps.

Jon

 

[Halo Jones]

Thanks guys. Was obviously being slightly paranoid. The table is cast iron and while I knew oak reacted with metal i did not make the link, I just saw a bit of straight, quarter sawn oak but my shop is too small to leave anything lying anywhere it should not be!

As a slight diversion from the original topic is there a good blade that will do cross cutting and ripping? My shop really is too small for both a table saw and a mitre saw, hence the need for a good sled.

Thanks again.

H.

 

[Steve Maskery]

Provided you are not cutting very thick stuff, a 40T ATB blade (assuming 10" diameter) will do a satisfactory job of both ripping and crosscutting, anything up to about 2" thick. Ask Doug Perry at Cutting Solutions what he recommends.
S