Using a Router as a Jointer

[dusty]

The router jointer idea works, been there, done that.

My question would be are you sure you need to do that operation. Using plywood, mdf core or what ever should cut up pretty well if you can use the table saw, as in no need to joint.

If you have to first cut up the sheets then I can understand that a circular saw might leave edges that need work but then they need to be fixed before you start doing sizing cuts. The point the edges get damaged is the the first point to attack in the process. Unlikely the router is the solution but rather a tool of last resort. Meaning that the better you start off the better you can end.

Just trying to lend some perspective to the process.

Ed

I guess my real problem, ed, is that I am cheap. I don't use my better saw blades to cut MDF and the saw cuts I am getting with the blade chosen for sacrifice are not real clean. I single pass across the jointer cleans them up well. But I also do not relish the damage done to my jointer blades by the MDF.

An inexpensive router bit sounded like the way to go.

[curiousgeorge]

I guess my real problem, ed, is that I am cheap. I don't use my better saw blades to cut MDF and the saw cuts I am getting with the blade chosen for sacrifice are not real clean. I single pass across the jointer cleans them up well. But I also do not relish the damage done to my jointer blades by the MDF.

An inexpensive router bit sounded like the way to go.

You got that right, Dusty. A router bit is a damned sight cheaper, not to mention easier, to change out than a Jointer blade.

[dusty]

You got that right, Dusty. A router bit is a damned sight cheaper, not to mention easier, to change out than a Jointer blade.

It does seem as though this should be easy (easier). However, I have imposed constraints that are making it not as easy as it seems it should be.

On my router table I use an Incra Fence. It is not one of the newer ones that can be "fine tuned". I can move the fence only in increments of 1/32" (or multiples thereof).

Sounds easy. If I want to joint off 1/32" all I have to do is shim the left hand fence so that it sets proud of the right hand fence by 1/32" and then adjust the entire fence so that it aligns "exactly" with the cutting edge of the router bit (here is where my problem begins).

My router table attaches to a Main Table on extension tubes (a 520 configuration). The physical relationship of these two tables is a variable.

The Incra fence attaches to the Main Table and its position on that table is a variable. I can loosen the mounting screws and move the whole fence in all directions about 1/8".

The Incra fence can be positioned in very accurate 1/32" increments.

Put all of these together in exactly the right position and I have a perfect jointer...but...don't change anything.

If anything changes, you have to start all over to the the relationships right.

I did that. I changed the value of the offset (the amount that I wanted to joint off). It happened that that amount was not in 1/32" increments and I now have snipe at the end. The snipe is small but it is noticeable.

It can be eliminated by simply correcting the offset between the two fences and setting the left hand fence to align with the cutting edge of the router bit (the bearing).

Simple in theory but not so simple in practice.

It is a good thing I enjoy this sort of challenge. If I didn't, I might not go back into the shop.

[fjimp]

On my router table I use an Incra Fence. It is not one of the newer ones that can be "fine tuned". I can move the fence only in increments of 1/32" (or multiples thereof).

Simple in theory but not so simple in practice.

It is a good thing I enjoy this sort of challenge. If I didn't, I might not go back into the shop.

Thanks for making me thankful I have the newer version of the Incra fence. In fact two of them. One for the table saw and a smaller unit on my router table. I have often marveled at how easy it is to set or reset accurately. Jim

[dusty]

Thanks for making me thankful I have the newer version of the Incra fence. In fact two of them. One for the table saw and a smaller unit on my router table. I have often marveled at how easy it is to set or reset accurately. Jim

My old one sets and resets easily. The downside is that all I get is 1/32" increments where you can dial in between those and you still have the same transportability and repeatability that I have.

There is no doubt, Incra has done wonders for the wood working world.

[keakap]

...
The Incra fence attaches to the Main Table and its position on that table is a variable. I can loosen the mounting screws and move the whole fence in all directions about 1/8".

The Incra fence can be positioned in very accurate 1/32" increments.

Put all of these together in exactly the right position and I have a perfect jointer...but...don't change anything.

If anything changes, you have to start all over to the the relationships right.

I did that. I changed the value of the offset (the amount that I wanted to joint off). It happened that that amount was not in 1/32" increments and I now have snipe at the end. The snipe is small but it is noticeable.

It can be eliminated by simply correcting the offset between the two fences and setting the left hand fence to align with the cutting edge of the router bit (the bearing).

Simple in theory but not so simple in practice.

It is a good thing I enjoy this sort of challenge. If I didn't, I might not go back into the shop.

Having a hard time envisioning the setup, but my thought is to pin an element once the proper positioning is achieved. Like once left fence aligned with bit edge and mounting screws (base?) tightened, drill for a tight fitting removable pin in addition so you can return to that exact spot.

This probably doesn't fit to your configuration but I'm sure you get where I'm heading with it. Idea being to return to sweet spot, whether with align pin, dedicated shims, template, whatever.

??

[Cavediver]

Having a hard time envisioning the setup, but my thought is to pin an element once the proper positioning is achieved. Like once left fence aligned with bit edge and mounting screws (base?) tightened, drill for a tight fitting removable pin in addition so you can return to that exact spot.

This probably doesn't fit to your configuration but I'm sure you get where I'm heading with it. Idea being to return to sweet spot, whether with align pin, dedicated shims, template, whatever.

??

IMO, a single piece plywood or MDF fence is the way to go for jointing operations. Cut a piece to width and length on the saw, move the fence in 1/16" or 1/32" for a cut that's stopped half-way through the board. Drill a clearance hole for the bit at the end of that stop cut and you've got a perfectly good jointer fence.

Granted, this setup is not adjustable, but it works well for most jointing tasks. I'd rather sharpen a blade sooner than deal with the math and precision required to joint opposite sides of the stock.

[dusty]

IMO, a single piece plywood or MDF fence is the way to go for jointing operations. Cut a piece to width and length on the saw, move the fence in 1/16" or 1/32" for a cut that's stopped half-way through the board. Drill a clearance hole for the bit at the end of that stop cut and you've got a perfectly good jointer fence.

Granted, this setup is not adjustable, but it works well for most jointing tasks. I'd rather sharpen a blade sooner than deal with the math and precision required to joint opposite sides of the stock.

Either I don't understand what you are describing OR what you describe doesn't work. Well, no - it works but it creates a taper.

There needs to be a dividing point (at the cutter location) between the infeed table and the outfeed table. The outfeed table needs to be forward of the infeed by an amount equal to the intended depth of cut (1/32" on my setup).

If I am missing something, please let me know that. You don't even need to be nice about it.

[Cavediver]

If I am missing something, please let me know that. You don't even need to be nice about it.

Lol.
Sorry, my description is lacking a bit.
If you take a piece of MDF, say 6" by 48", and shave 1/32"-1/16" off of one half of one long side (the stopped cut), you're left with a 48" board that's 5-15/16 wide from one end to the middle, and 6" wide from the middle to the other end.

Bad keyboard art to follow:
___________________________

___________O--------------------

Position your router bit at the center, and align the left half of that fence (outfeed side) flush to the cutting edge.

The infeed and outfeed sides are parallel. It's the same effect as shimming out the outfeed side of a fence, except you don't have to worry about keeping the infeed and outfeed sides parallel (assuming your saw is up to the task).

[Gene Howe]

Before I got my present adjustable fence, I just used an mdf fence about 3" high with about 2" of material on the back side for clamping and stability. Then, I laminated a piece of Formica to the out feed side.
It then became a dedicated jointer fence. Easy enough to clamp one end and adjust to the bearing on the out feed side and then, clamp that side.
Worked for me.