technical advice is requested:
i need to cut some long narrow strips (4ft long, 1/4″ wide and 3/32″ thick) from a 4ft long plank of 4/4 purple heart that is about 5.5″ wide.
i will be inlaying those strips into a dado (1/4″ wide and a tad under 3/32″ deep) along the length of the face of (many) ash picture frames i’ll be making.
i have a thin rip guide, an incra gauge that can be attached to my table saw fence (if the incra gauge is needed), a grr-ripper push block system, and a 1/16″ thick 10″ table saw blade.
i don’t have a bandsaw of adequate quality for any of the cuts.
should i cut the 3/32″ strips first from the edge of the plank or 1/4″ strips from the edge of the plank?
once i get those strips, i’ll need to cut them again, so they are 3/32″ x 1/4″ (and 4ft long).
the grain of the purple heart plank is such that the appearance is without significant difference whether i cut the 3/32″ strip off the edge of the plank first or cut the 1/4″ strip off the edge of the plank first.
what is the safest way to cut make the first and the second cuts, to get the 4ft long x 3/32″ x 1/4″ strips?
i was thinking of cutting the 3/32″ thick strip from the edge of the 4/4 x 4ft long plank, using the thin rip guide.
i was thinking of using the 1/8″ leg on the grr-ripper push block combined with the thin rip guide to make the 2nd cut.
making the 2nd cut is more of a safety concern for me, as it will be a 4ft long x 3/32″ thick strip of 4/4.
making the 3rd cut is even more of a safety concern, as it will be to get a 2nd cutting from the 4ft long 3/32″ strip that is now only 1/2″ wide (4/4 plank is 13/16″ thick; the math: 13/16″ – 1/16″ kerf – 1/4″ strip).
there won’t be enough left over to get a 3rd 1/4″ strip. (rather than wasting this leftover, maybe i’ll use the narrower leftovers for proportionally smaller 4″x6″ frames.)
i’ll need to make about 64 of these 4ft long strips.
i have more purpleheart planks if needed.
if you suggest another another approach, i’m all ears.
Replies
From a safety standpoint I would avoid having to make a second cut on an already narrow strip on the table saw. One way to get around that is to start with the plank thicknessed and final surfaced to down to 1/4” thick. Then you could safely rip the 3/32” strips off of the plank. I’d stop ripping strips when the plank gets narrower than an inch or so, whatever you can still control well with your Grr-ripper. Wasting a bit of lumber is a whole lot more economical than a trip to the ER!
Starting off with a 1/4” thick finished plank will also ensure uniformity of that critical dimension, something that would be difficult to achieve over multiple rip cuts. Also make sure the 1/16” blade doesn’t vibrate — some blade stiffeners might be helpful.
Given your bandsaw comment, I don’t know if you have the means to resaw and surface 4/4 planks, but it is worth figuring out for your own safety.
Give this a try. It has worked for me. It's very safe and easy.
https://www.youtube.com/watch?v=fvMrDNPSoRM&list=PL6KVqVeh8v4XOygjdqZQfFCx4DXpd1-Vz&index=32
I watched RevBob's linked video. There's no way I can think of to make it work for the OP's 4' long parts. I use a magnet on the table with a spacer to reset the fence and cut them slightly oversized, then I bring them to size with the drum sander.
Do they hafta be 4' long through the whole cutting process? If they are inlay, would it be possible to inlay shorter lengths?
I have used the method that Kevin Rodel showed in this video workshop to make 1/8" and 1/4" wide inlay from 1/16" thick veneer (~6" x 24")
https://www.finewoodworking.com/2017/07/27/ep-6-inlay-prep-creating-banding-templates
@3:48
I used 1/16" veneer (2ft in length ), rather then ripping 1/16" thick stock from 8/4 as Kevin does. The hold down board that he uses to bury the blade into looks to me to be to narrow front to back.. I used a 2x4 and it needs to be centered on the blade if the board is a little off of center it can expose a little of the blade in front or behind the hold down board. Kevin also have a sliding table on his table saw.. I don't and found it easier to stand at the side of the machine and feed the stock in with two hands and when it was 3/4 of the way through I used my left hand behind the hold down board on top of the inlay and waste to continue feeding it through the blade... the last 3" was sometimes a little thin (width wise).. I would also shoot the veneer
stock with a hand plane to make sure the edge was straight before each rip..
If you were to ensure all four corners are square,you could set your fence for one measurement and blade height for the other. Run all four corners with the board on edge, then reverse the measurements with fence and blade height then cut again on the flat. I've found that the blade will push the cut off back to you, but not terribly fast, and you'll be standing to the side anyways. Rejoint the edges and repeat in reverse order so you only adjust once every 4pieces. Hope that helps.
Tom McLoughlin (Epic Woodworking) just had a YouTube video drop recently where he needs some thin long material for inlay. He used the bandsaw and created a zero clearance throat. Looked easy to do. I'd go check that out.
Working from some others' suggestions, here is a safe way to do it, if you either have a thickness planer or have access to one.
Rip the planks down the middle to have two ~2.75" boards. Resaw them on edge on the table saw making two thinner boards from each, then thickness plane the four boards to 1/4" boards. As mentioned previously, this is much more accurate for sizing the inlay in its critical dimension than sawing on a table saw. I'm not sure I would use the 1/16" blade for resawing that depth of cut; a stouter blade would be safer, since you have extra thickness. If your table saw will struggle with that depth of cut, you can either cut the original planks into 3 pieces, or make the full cut in two passes, the first not to full height.
Once you have the 1/4" boards, it can be safe to rip the 3/32" strips if you set up properly. First, you need a zero clearance throat plate. Then either a riving knife or splitter behind the blade. Also a good outfeed support, so you don't have to push down hard on the board as it hangs over the back edge. Lastly, you make a couple of my favorite push devices from 3/4" plywood, which I will show a picture of. (Your bandsaw or saber saw will be adequate for this job.) Make the "foot" at the back end a bit less than 1/4" tall, so it won't hit the table saw table.
Set your fence to the desired width of cut (3/32") with the blade high enough to cut the strips, and as high as the splitter if it is fixed in place. Run one of the plywood push devices thru the saw, up against the fence, to groove it where the blade is. Now just start ripping thin strips one after the other. Use the second pusher in your left hand to keep the board tight against the fence, pushing in front of the blade, not next to it. The primary pusher feeds both the thin strip and remaining board past the blade. Pay attention to the straightness of the sawn edge on the remaining board, as it may need to be jointed sometimes. Also make sure the back edge of the saw blade is not closer to the fence than the front edge. On normally thick boards, I typically only have the saw blade protruding above the board a bit more than the height of the carbide teeth. On thin rips, it is safer to have the blade a bit higher above the board, to apply more downward pressure to the board. This prevents the board vibrating or being pushed upwards and slammed down on the table, an event that both damages the board and scares the woodworker (and rightfully so!)
By the way, I make these pushers in batches, out of different thickness of plywood scrap, and keep them handy at multiple machines: table saw, jointer (for the rear hand), band saw for ripping, router table, etc. The long bottom of the pusher, ahead of the foot, needs to be slightly concave, so that the front and rear both make good contact when in use.
When I do inlay I always leave the inlay a little thicker than I need. I then sand, plane, or scrape it flush when I'm done. This lets me not worry as much about getting that dimension perfect or honestly really close. I'd focus on getting the width right while using a bigger piece.
When I need to make really thin strips to use for inlay work, I use double sided tape to stick the inlay piece to a larger board and than do a non-through-cut. I cut through the inlay piece, but not the "safety" board. If you are doing a lot the same size, the safety board is reusable. Just be sure it is straight and flat before you start.
thank you to y'all who contributed suggestions.
some of the suggestions were totally new concepts to me.
Glue it to a wider bit, so it's safer in the small bits.