# How do I size a spline



## Sparks (Nov 24, 2004)

I'm building a 1-3/4" x 4' x 6' maple butcher block top for our new kitchen island. I glued the individual boards into four 1' x 6' pieces and ran them through a thickness planer. I don't have a jointer, but I remembered seeing Bob's router workshop show about matching laminate countertops, and used the same method to match the edges.

I plan on using a 1/4" slot-cutter and splines to join the sections so that the surfaces match up as evenly as possible.

My question is: How do I size the spline thickness and width to the slot size and depth? If the slot is 1/4" wide and 9/16" deep, how thick should the spline be and how wide?

I've done a few test thicknesses, with the spline 1/64-inch under sized it seems too loose, a 1/4-inch thick spline fits great, but what about an allowance for glue? The same with the width. How much should I allow for glue with the two 9/16-inch slots? Would a 1-inch wide spline, leaving one sixteenth on each side, leave enough room for glue? I would hate to discover I didn't leave enough room for glue when everything is glued up and I can't pull the pieces together.

Sparks


----------



## DavidF (Aug 19, 2010)

I would make the loose tenon a millimeter too shallow both ends. Then heavily score the faces of the tenon, all four of them, from end-grain to end-grain (as in shop bought dowels). Then use the tighter (1/4") spline but the minimum of glue. If you don't do them all at once and use a slow setting glue you should have time to pull it apart.

Why don't you glue up the parts that you cut as a test?


----------



## dutchman 46 (May 23, 2007)

Hello n/a , I don't have an answer, and I don't know if others do. The one thing that You can do is to add Your name. and a place(area) Where You live. We are not able to answer You if You go to a different area. Thanks !


----------



## Mark (Aug 4, 2004)

dutchman 46 said:


> Hello n/a , I don't have an answer, and I don't know if others do. The one thing that You can do is to add Your name. and a place(area) Where You live. We are not able to answer You if You go to a different area. Thanks !


Please be aware of the new forum policy.

http://www.routerforums.com/routerf...23121-router-forums-personal-information.html


----------



## Quillman (Aug 16, 2010)

How do I size the spline thickness and width to the slot size and depth? 
*********************
Measure x & y of held-together pair of slots.
Subtract .005" from x & Y.
Mill thickness of spline stock to (in you case) 9/16-.oo5".
Rip said blanks to ~5/16". Plane to .245" on an MDF or flat piece of wood. Done city.


----------



## bobj3 (Jan 17, 2006)

Hi 

How about using a pair of slot cutters on one router bit arbor, pass it by the bit and presto you have splines that are true and ready to use once you rip them down to size on the table saw..you can make more than one if you stack the slot cutters up...I use 3/32" slot cutters to make 4 in one pass of the bit. 

========



Quillman said:


> How do I size the spline thickness and width to the slot size and depth?
> *********************
> Measure x & y of held-together pair of slots.
> Subtract .005" from x & Y.
> ...


----------

