Accessory Table and SMT

[DJB]

My BT3100 is still in the box while I clear out enough space in the basement to set it up. In the meantime, I was wondering...

Is there room on the rails to set up the SMT next to the Accessory Table? I am wondering, because I would like to put a router in the Accessory Table and use the SMT to feed the stock into the router.

Thanks,
Dave

[LarryG]

Yep.

Yes, you CAN do that, by adjust the BT's sliding rails such that there is room for both the SMT and the accessory table on the same side (left or right, your choice) of the fixed main table.

However you may not WANT to do that, if your intent is to use a fence with the router. In that case, a sled that holds the workpiece and rides along the face of the fence would be better.

[DJB]

Explanation

Thanks for the help.

One of the first projects on my list is a small knick-knack display cabinet -- basically a 2' x 3' x 3" deep open box to mount on the wall, with a variety of shelves and cubby holes in it. I was thinking about using the router to cut dados in the uprights to support the little shelves. I thought that the fence is used when cutting a groove along the length of the workpiece and that I should use the SMT to push the piece and maintain it at 90 degrees when making a dado across the 3" dimension.

Should I be thinking of building some sort of sled, instead? Is the sled basically a right-angle mitre that slides along the fence to push the workpiece, or do you mean something that would actually support the piece from below, as well? Seems like it would have to be a 2-piece sled bottom to allow the dado cut. Are there any plans or pictures of a sled you can point me to?

Thanks,
Dave

[LarryG]

That's the way, uh-huh, uh-huh ...

Dave,

Given your more detailed explanation ... yes, you're very much on the right track. If you're doing something like exposing tenons, a sled that holds the workpiece and slides along the fence is best. For dados, any method that ensures the workpiece doesn't move from side-to-side is fine; for that, using the SMT as you describe would be a good solution. You don't need a fence at all, in this case.

"Basically a right-angle miter that slides along the fence to push the workpiece" is a good description of a sled. Usually it will have toggle clamps to keep the workpiece from moving around, and a backer block of scrap material, to prevent tearout as the bit exits.

A little tip for a project like your knick-knack cabinet ... instead of cutting all your uprights to width and then cutting the dados, do it the other way 'round: cut the dados in a single wide piece, then rip it as required to produce your verticals. This ensures that the spacing of the dados will be exactly the same on both end of the little shelves. It's also a little faster since it reduces the number of pieces you have to handle.

[DJB]

Closer, closer...

Larry,

I'm glad to see that I am on the right track. Thank you for the advice and comments.

I like the idea of a sled/mitre, because using one might be easier than re-adjusting the rails to fit the SMT next to the accessory table each time I want to route a dado. (I don't have a dado blade for the saw.) "Easier" would also mean that I am more likely to use it. If I make a bottomless sled to make the depth-of-cut measurement easier (basically just a mitre), then I'll have to think about how to clamp down a 3/4"-thick piece of wood that would lie flat and yet still allow the piece to slide on the table top.

I need to think about how to build a sled that I could butt up against the fence and how to ensure the 90 degrees between the side of the sled that contacts the fence and the "pusher" side that contacts the workpiece.

I really like your tip about cutting dados before ripping!

[linear]

I need to think about how to build a sled that I could butt up against the fence and how to ensure the 90 degrees between the side of the sled that contacts the fence and the "pusher" side that contacts the workpiece.

I just finished my sled yesterday, so no pics yet, but I used some dowels to pin it through the holes in the SMT that the pivot pin for the SMT fence fits into.

So all it took was drilling two properly spaced holes in the plywood scrap, then setting the back fence on the sled perfectly square to the blade.

[LarryG]

Dave,

What you described ("a sled that I could butt up against the fence and how to ensure the 90 degrees between the side of the sled that contacts the fence and the "pusher" side that contacts the workpiece") is what I would call a push block. Assuming I'm reading you right: that will work, but a sled usually has a base plate on which the workpiece lays and to which the fence, which does the pushing, is attached. Reading Rob's description, this sounds like how he made his.

I have no pictures of mine either, so here's a link to a fancy commercial version, with the full complement of bells and whistles:

http://www.hartvilletool.com/product/11385

Mine is much simpler and was dead easy to make. Just a piece of 1/2" MDF for the base, a scrap of oak for a fence, and a couple toggle clamps. The only critical issue, as you say, is making sure the sled's fence is perpendicular to the edge that indexes against the router table's fence.

Since the workpiece is clamped atop the base plate, everything moves together and thus there's no need to grow an extra hand so you can hold all the pieces together. However, because the workpiece sits atop the base plate, the bit must be raised by the corresponding amount (1/4" for the sled in the link, 1/2" for mine).

I have another, larger sled, similar in concept, that I use to hold long skinny workpieces when I'm profiling their edges; i.e., the long dimension is sliding along the fence. I'll make a mental note to take some pics of both of these and post them.

[ErikS]

Here's one that's a bit cheaper (I use it to cope the ends of R&S work) -

http://www.mlcswoodworking.com/shops...ssorysafe.html

Pretty easy to DIY.

[DJB]

LarryG and ErikS,

Thanks for the pictures, guys! I just wasn't getting the concept right--I kept thinking that the sled had to support the workpiece on both sides of the router blade while making the dado cut (which would be a bit hard to do). It just didn't occur to me to let it hang over the edge of the sled without the far side being supported.

Seeing the pictures give me a much better idea of what I would need to build.

Dave