Replies

1. 
   QCInspector | Feb 22, 2006 01:13pm | #1

   Sorry to hear about the injury, and I can understand why you may be exercising more caution.

   You past method is usually fine but if the starting block clamped to the fence is kept low then you can use a push stick to keep your back hand clear. A second short fence clamped in front of the blade to form a channel with the blade in the middle will trap the stock so that it can't roll when lowering it onto the blade.

   If the above still gives you reason to pause then you could consider making a holder / box of 2 pieces of plywood with a spacer the width of the stock you wish to grouve. The holder / box being tall enough to hold safely and securely, with the edges well rounded so that in the remote chance it does kickback it won't cut your hand. It will work the same as your old method. The downside is the time it takes to make it (especially is it's for only a few pieces) but reusable for future projects.

   If the purpleheart is still wide and not ripped into narrow pieces. then you have the option of plowing the groove on each side and then ripping to width. Easier to handle wider boards.

   I wish you a speedy and full recovery.

1. 
   John_D | Feb 22, 2006 11:02pm | #6

   You past method is usually fine but if the starting block clamped to the fence is kept low then you can use a push stick to keep your back hand clear.

   I agree on the push stick, but the hard part of this operation is lowering onto the spinning blade, which I don't think I could do from anywhere but behind the stock.

   A second short fence clamped in front of the blade to form a channel with the blade in the middle will trap the stock so that it can't roll when lowering it onto the blade.

   Hmm, you mean basically something to perform the function of a featherboard, holding the stock against the saw's fence?  I'll have to think about that, that might be pretty useful.

   Not sure I'm feeling good about this overall, though.  I'm happy to plow a through groove with the dado, but I've had a belly full of dropping stock onto a spinning blade for now.

   I think I will use the router, make a quick jig, and plunge cut the groove with a spiral bit.  It's only a small PITA and it won't take much more time than the dado method.  A little more setup, but actually less time cleaning after (much more chiseling on the TS ramp than on what the router leaves).

   Thanks too for the suggestion on the half-blind.  For design reasons, I want to stick with through DTs.  But, as you suggest, by locating my pins and tails carefully I can avoid needing a stopped groove on the sides, just run 'em on the ends.

   I had to teach myself most of this stuff (from books and videos), so it's really nice being able to ask more experienced folks about difficult operations.  Thanks to everyone who kicked in on this thread.My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

1. 
   BG | Feb 23, 2006 03:45am | #7

   John_D,
   One additional suggeston: use a circular saw with a jig and stops...think it would be a whole lot less dangerous than the TS

2. 
   ring | Feb 22, 2006 01:57pm | #2

   John,

   I personally would rather do it in 2 passes with an undersized router bit.  If it's only a few pieces, then the time involved is no big deal.  And if you have a lot to do, then it's worthwhile to buy the right sized bit for it.  The TS routine will work, but I'd feel better with the router on this.

   DR

3. 
   hammer1 | Feb 22, 2006 04:43pm | #3

   Your technique on the table saw would work. Having a stop block at each end is very necessary. The problem is dropping the piece perpendicular and preventing burning on both the drop and the stop. The stop also leaves an arc cut which may require some extra hand work.

   I would prefer to do this on the router table. There are many size choices in straight bits including those made for plywood. You can use a long fence with stop blocks just like on the saw. One option, if you can't find a bit that fits, is to shoulder the panel. Another option is to rabbet the corners the depth of the groove and hide the opposite groove in a tail. If you use a smaller router bit and make two passes, make the cut next to the fence first then move the fence back. If you move the fence in for the second cut, the rotation of the bit will pull the piece.

   Beat it to fit / Paint it to match

4. 
   joinerswork | Feb 22, 2006 04:48pm | #4

   John,

   Consider using half-blind dovetails, instead of through dovetails.  If you locate the groove between pins, it won't show, and you don't have to stop it short of the end of your stock. 

   Regards,

   Ray Pine

5. 
   BOBABEUI | Feb 22, 2006 04:50pm | #5

   Hi John,

   Sorry to here about your injury.

   I would say that if something feels unsafe to you, then it more than likely is (or will be). I personally would perform this step on the router table, as performing a stopped dado on the tablesaw does not feel safe to me.

   Best of luck

6. 
   pzgren | Feb 23, 2006 08:02pm | #8

   John,

     Sorry to hear about your injury.

     I'll take as little different approach here...   Have you considered making your stopped groove(s) by hand? A good saw, a little chisel work and a router plane for finishing the bottom....you're done, and it's pretty easy to get the size just right to fit the thickness of your piece of plywood.

     Just another way to approach it.

     Good luck...and watch out for them electron munchers...they eat other stuff, too...

   James

1. 
   John_D | Feb 23, 2006 11:48pm | #9

   I don't understand how I'd use a saw in making a stopped groove by hand?  In any case, I like your suggestion and would consider it, but don't have a router plane.  I do have a router, so I think I'll proceed on that path.  But I'll chop out the ends square by hand with a chisel.  :)My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

1. 
   pzgren | Feb 24, 2006 02:00am | #11

   John,

   <<I don't understand how I'd use a saw in making a stopped groove by hand?>>

     Quick description: Lay out as usual. Use a small saw (dovetail saw, stair saw, small dozuki or -- better -- an Azibiki or Kamibiki -- Japanese mortise/slotting saws) to cut the walls of the groove. [Depending on your hand saw skills, you could use a guide block clamped to the board, parallel to the groove layout line, to keep your saw at a 90* angle and to keep your cut straight, for straight groove walls.] Cut the groove walls on each side to depth almost up to the place where you want your stop. Once you have the walls cut to depth, then you can cut a couple of kerfs in the center of the groove almost -- but not quite -- to depth; but these cuts are not necessary. Then use a chisel to remove the waste. The center kerf(s) make waste removal go faster and seem to reduce tearout in the bottom of the groove. Once you have removed the waste, you can clean up and finish the stop cut with your chisel(s). Cleaning up the bottom of the groove can be done with a router plane, a crank neck chisel, or a paring chisel with the bevel down. Router plane is just the fastest and easiest way to do it.

     This is basically the same procedure as cutting a through or stopped dado/sliding dovetail by hand; only real difference is the direction of the cut.

   http://www.norsewoodsmith.com/index.html  Click on the "Making Dados With Hand Tools" link on the left hand side of the page. This page has an example of making dados and stopped dados (toward the bottom of the page) with hand tools. You'd use the same procedure for your groove, only changing the orientation of the cuts. Lots of useful pictures.

     Hope this is of some use to you now or in the future

   James

1. 
   John_D | Feb 24, 2006 03:56am | #13

   Glad I asked the question, I really learned something.  Read the link too, thanks very much!My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

1. 
   pzgren | Feb 24, 2006 06:19am | #14

   John, Glad to have been of some help. Looking forward to seeing some pics of your project when you get it done.James

2. 
   Crocusboy | Feb 24, 2006 08:17am | #15

   I have used both router and TS methods and far prefer the TS.  Perhaps it's because of my TS and the efforts I make to ensure it is running true.  My Delta Unisaw is one incredible machine and I take the time to adjust the blade as perfectly parallel to the fence as possible, whenever I notice the slightest indication of it going out of true... which isn't very often.  In addition, I make sure that I deliberately lower the wood onto the table's surface and keep a firm grip on it as I advance it.  I don't use feather boards, as they get in the way of lowering the board onto the blade.  I use a push stick, and if the piece is less than a few inches wide, I use a second push stick to hold the piece to the fence, as soon as I can pick one up after I've lowered the wood onto the table.

   My personal experiences with routers are less then positive, as I've had more pieces of wood ruined by the bits wandering off course than I'd prefer.  Perhaps it's my technique, but as stated above, I'm really happy with plowing stopped dadoes on my TS.

   My advice is: "get back on that horse" and regain your confidence.  Good luck.

   Marty

3. 
   John_D | Feb 25, 2006 01:04am | #17

   I'm confident my TS is set up well, and as I say no hesitation in plowing through dados.  The only sticking point for me is the actual moment of lower the stock onto the spinning blade.  I agree, if I do it, the firm grip is essential.  Still, I remain convinced it's the most dangerous operation I've continued to contemplate in my shop.

   I've no worries about a router bit wandering on me.  For one thing, the jig I'll construct won't allow that to happen.

   I appreciate the advice, but absent concrete suggestions that make the operation safer, I intend to proceed with the router plan.

   I can't wait to get back in my shop next month and get to making stuff again!My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

7. 
   douglas2cats | Feb 24, 2006 01:49am | #10

   Personally I'd go with the router, but if you're still looking for a safer way to do it on the TS I'd try this: Set the height of the blade and put a marker on the height adjustment wheel and the saw. Then lower the blade beneath the table before each cut. With the wood firmly held down, raise the blade until the 2 marks align then push the wood forward and stop the saw at the end of the cut. I think routing would be a whole lot easier though.

   If you build it he will come.

1. 
   John_D | Feb 24, 2006 03:55am | #12

   That's an interesting idea too.  I'd thought of it, but it just seems clumsy, fumbling under the table with one hand while holding the stock with the other.  I'm pretty much settled on using the router.

   Thanks!My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.

8. 
   AlanWS | Feb 24, 2006 09:17pm | #16

   This is just an idea that I've not tried, but...

   What if you made a panel cutting sled, but made the beginning of the rail that runs in your miter track extra thick. With the stock in the sled, the thick track would raise the front part of the sled above the blade. As you slide the sled forward, the thick part of the rail could slide off the back of the saw, dropping the sled down flat onto the table, and engaging the full length of the normal rail. Continuing the cut would cut the rest of the groove, and a stop block could limit the sled travel on the other end.

   If the depth of the groove is smaller than the thickness of the ordinary rail, you could do this simply by attaching a block to the bottom of the sled to hold the beginning of the workpiece up off the blade, while letting the rail align the sled.

   This would take some checking to make sure the sled could not wiggle sideways as it set the work down.

1. 
   John_D | Feb 25, 2006 01:05am | #18

   Interesting idea, thanks.My goal is for my work to outlast me.  Expect my joinery to get simpler as time goes by.