LumberJocks

Getting a straight fence for cross cut sled

  • Advertise with us

« back to Jigs & Fixtures forum

Forum topic by Lookwow posted 05-14-2018 04:05 PM 1599 views 0 times favorited 4 replies Add to Favorites Watch
View Lookwow's profile

Lookwow

11 posts in 467 days


05-14-2018 04:05 PM

So I have tried several times using multiple pieces of 3/4 in plywood to get a straight fence without bow/warp and every time I end up with some amount. Maybe not right away but over 4 months or so it warps some.

I’ve been debating between doing a one miter slot sled with some extruded aluminum or getting a after market miter gauge.

Any tips on getting and keeping a straight fence or what you would do.


4 replies so far

View Loren's profile

Loren

10477 posts in 4100 days


#1 posted 05-14-2018 04:28 PM

I had one where I used a piece of angle iron
with a board bolted to it and shims in between
to square it. Both steel and aluminum angle
are quite straight generally.

MDF or melamine may stay straighter than
plywood in this application. Plywood still
has intact wood cells in it that absorb moisture
through the exposed end grain and may
“wave” with fluctuations in ambient humidity.
I don’t know why plywood does this really,
but it’s definitely not a material that can be
relied on to stay dead flat if it isn’t fastened
down or evenly supported.

View Robert's profile

Robert

3482 posts in 1933 days


#2 posted 05-14-2018 06:52 PM

Screw vertical fence to the factory edge of plywood and add a few 90° braces. Screw this assembly to sled base.

Screw one end tight and then do your 90° adjustment.

Try using AZAK for runners. Lotsa screws/best with a shallow dado.

-- Everything is a prototype thats why its one of a kind!!

View bbain32's profile

bbain32

33 posts in 1628 days


#3 posted 05-29-2018 02:09 PM

I made the fence for my main crosscut sled by laminating 3 pieces of 1/2” plywood together.

When I did the glueup I clamped it down to the top of the tablesaw (with wax paper in between) as it is the largest flattest surface in my shop. it seems to have stayed true enough for my purposes.

View jonah's profile

jonah

2075 posts in 3751 days


#4 posted 05-29-2018 02:18 PM

Look at using aluminum extrusions. They’re dead flat (or close enough for our purposes, anyway), and you can get them delivered to a Grainger store for free. You’ll spend maybe $30, but you get a very flexible, easily adjusted fence that is definitely dead flat and will stay that way.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com