How do you deal with non standard miter slots?

[Alex Zeller]

I just discovered that the miter slot (not a T slot) isn't a standard size. It's 3/4" wide but only 5/16" deep. I was going to use my miter gauge with it but obviously it wouldn't work. Being for a miter gauge wood or plastic seams too weak. I looked into getting a piece of precision ground steel or aluminum but the steel seams to only be in tool steel (which would be much harder to drill and tap). So far I can't find any aluminum 5/16" thick. Does someone have a source?

[ChrisA Edwards]

Will not 1/4" work for depth?

[Robert Hayward]

I do not have a source for 5/16" but I believe 1/4" should work. You do not want the miter bar to drag on the bottom of the miter slot. There are plenty of hardwoods that would be strong enough for a miter gauge bar.

[Jim Becker]

Make it from scrap oak flooring material. It's plenty strong enough. Mill it exact width so it's actually tight and very carefully sand off the edges with a hard block or abrasive stuck to a hard surface to relieve it just enough so it slides freely. Countersink for your fasteners and you'll be up and running.

[Alex Zeller]

It's actually slightly deeper than 5/16" so 5/16" wouldn't drag. The main reason for going with that size was to have a little more thickness for threads. But I could use a flat headed screw from underneath and counter sink it with a lock nut on the top side. I had thought about making a coping sled for it.

[Jim Matthews]

As suggested by JB above, make a glide and countersink it.
If you can afford to give up some depth of cut, UHMW plastic fixed to a plywood "tray" is handy.

My sliding table for my bandsaw is indexed this way.

https://m.imgur.com/a/bLrcA2V

[Richard Coers]

Ive never purchased anything for a miter gage slot. All my jigs and fixtures are made with wood runners. Waxed hard maple last an incredibly long time.

[Bill Dufour]

My tablesaw slider uses a oak runner. been fine for 20 plus years so far. Tee nuts can help attach things together.
Bil lD.

[Bobby Robbinett]

I never have liked the idea of using solid wood miter bars due to the expansion and contraction of the wood. Even if it still fits good with the changing seasons it could quite easily end up not being square over time. If it were me, I would talk to a local machine shop about making one out of steel. You can even drill and tap for small set screws to make it fit tighter and have some adjustment for squaring things up. I am having a local machinists make one for me for my big Delta 12/14 table saw that has a 1.25” or so slot since non were available on the used market and Delta no longer carries parts for their older stuff. I think he quoted me something around $100.

[Will Boulware]

My Crescent saw has a 1" by 1/4" slot. I ordered a piece of steel from McMaster and had a local machine shop drill and tap it for an Incra gauge. Works great!

[Tom Bender]

I haven't used a mitre gauge in years. This sled is much better and safer. It has an Oak runner glued to the bottom. 3/16" Lluan ply and a Basswood fence make it a one handed install.

sled.jpg

Lots of ways to make angled cuts.

[Lisa Starr]

McMaster Carr has "tight tolerance" low carbon steel available in a 5/16" thickness. It is +/-.003", so pretty likely to fit without requiring any machining.

[Alex Zeller]

I did look at McMaster's products. Everything they had was tool steel and harden steel except for their "low carbon" steel. I actually was going to order a piece but in their description they say it can be heat treated. Normally low carbon steel can't be hardened. I was going to call them and ask for more information but got sidetracked. They don't say if both sides are precision ground or just the thickness. The 5/16" dimension doesn't need to be too precise but the 3/4" side does. If both sides are precision ground how flat are they over a distance. What I was thinking is that for less than $60 you can get a 1/2" x 1" steel bar 3' long which would be useful for setting up tools as long as it's flat enough.

[Lisa Starr]

Alex, The "tight tolerance" Low Carbon steel from McMaster Carr probably isn't machined at all. Cold Drawn steel is in the +/-.003 range when purchased from a reputable mill.

[Alex Zeller]

I assumed it was precision ground steel since it's listed under "precision ground steel" on their site. But there's nothing saying it's actually precision ground. Sounds like I need to call them for answers. Thanks.