Incra Fence and router bits

[Josh Bowman]

I just got a new to me Incra Ultra router fence. I've been playing around cutting box joints and find with my hodge podge of bits, he joints are either too tight or loose. Is there a brand that had better results with the Incra? Should I buy a set like the Whiteside 605 for $88? I have a Leigh dovetail jig and will most likely use it and my Leigh bits to cut drawer dovetails.

[Jay Jeffery]

If you have a Leigh jig, why do you plan to cut dovetails on the Incra? I've never used a dovetail jig, and myself just recently got a new to me Incra Pro jig (prety old actually) that I haven't set up, but it seems to me the Leigh would be better suited for dovetails.

From what I can see, it looks like the Whiteside Incra set just has standard 1/4" and 3/8" straight bits. You might want to measure the kerf of the cuts you get with the bits you have now. Also check the alignment of your router bits to the table top to be sure it's perpendicular in all directions. If the bits are off, you could just get the Whiteside bits you think you will use. Maybe that's the whole set.

[Ben Davis]

I just got a new to me Incra Ultra router fence. I've been playing around cutting box joints and find with my hodge podge of bits, he joints are either too tight or loose. Is there a brand that had better results with the Incra? Should I buy a set like the Whiteside 605 for $88? I have a Leigh dovetail jig and will most likely use it and my Leigh bits to cut drawer dovetails.

Josh,
The Whiteside bits are top notch... no doubt about it. An added benefit is that most (I would say all, but then I would be proven wrong) of their bits are made just up the road from me in North Carolina. I like to keep my dollars in this country thank you...

I have never once had a problem with Whiteside bits failing. Perhaps it's just my good luck

[Jerome Hanby]

I haven't mounted my Incra joinery system yet, so I can't give specific details on how well everything works together, but I bought a set of bits (8 I believe) marketed for use with the Incra system. I'm pretty sure it's the
Freud 96-102 8-Piece Dovetail Incra Jig Bit Set with 1/2-Inch Shanks (http://www.amazon.com/gp/product/B0000225YY/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B000CS7DB4&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0XR4MG8DWS9FTH41CF0C)

That's an amazon link. If you buy them be sure to go through SMC's link.

[Chip Lindley]

The LEIGH D4R jig rulez. I got perfect results the very first time. That, of course was with a set of brand new, sharp bits.

If dovetail bits are resharpened, they are smaller by a very few .001"s. That could certainly make a difference. BUT the Incra stuff touts adjustment down to .001"! So, that would lead me to believe you could adjust out the deviance.

Other cause of inaccuracy when routing a line of box joint or dovetail slots, is that the bit can often "pull" the wood if not "seriously "clamped". Sandpaper glued to the hold down device can help here.

[Josh Bowman]

No way would I have believed this, but run out was most of the problem. I checked it at 9/1000, not much, but when the joint was 12/1000 from tight, which meant the joint would just fall apart if let go. So I pulled the 1/4" collet and blew all the saw dust out and rechecked the run out at 3/1000. The first box joint attempt, I ran only one pass for each cut......a real slow pain. The joint was acceptably tight. The next try I ran two passes, iaw made the cut and just moved the wood back over the bit. That one also a very good fit.

[Jim O'Dell]

I have the Infinity set for mine, although I haven't used them yet. I did cut my fingers on on of the dovetail bits putting in the holder in my bit drawer...it even still had the protective rubber goo on the bit! Not THAT'S SHARP!!! Jim.

[Alan Schaffter]

Box joints require precision cutting.

Router bit and dado blade sizing can unfortunately be imprecise- and not what is published. A box joint requires the width of the spaces cut by the bit be exactly the same as the width of the fingers. Template or incremental type box jigs rely on a perfect match between the template and the bit/blade. A jig which can be precisely adjusted for a less than standard bit/blade sizes is needed. A new solution will be available later this year.

Collet and blade runout, as you found, can also affect box joint fit. Bad user technique will also affect joint fit- especially when using a box jig on router table. If you don't hold or clamp the stock securely against the fence, the router bit and its rotation will cause the stock to move sideways resulting in a skewed notch or one that is too wide. This is especially true if you are using a dull bit. Also, if you feed the stock into the bit too quickly the bit can flex making a slot that is also too wide.