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Safety question about upright very acute angled cut on a 5/8 panel3/30
Not sure if this is the right forum section--it's a machining question, but not hardwood.
There is a type of hood box that we make that has a front plate cover that involves a taper and a whole lot of funky angles/miters.
The top part needs to be around 14 degrees (varies a bit with dimensions/projects) where the plate meets with the box (see pic).
Two other people in the shop's methods:
--one does an upright freehand cut on the table saw. He's supertall and long armed (operator height really does matter on this one).
The other guy uses a handheld belt sander with 80 grit to get the dimension.
One method is a bit sketchy, and the other not precise.
Perhaps there is a method that is both precise and safe? I'm thinking a very acute angle machining jig of sorts?
just occured to me-- "freehand" isn't the right term really.
It's against the fence, but seeing as it's a panel that is anywhere from 30"-40" x 20"-30" depending on the project, "against the fence" is a little hard to controle perfectly.
I don't exactly understand the cut you're making, but if keeping a tall panel against a fence is the root of the problem, making the fence taller seems the solution.
We make splined corner picture frames. The basic process is to join the frame with glue, then stand the frame up on edge at a 45* angle to cut the splines. Since we often make frames in the 30x40 range we needed something that would keep them vertical. We used a tenoning fence as a starter, because we wanted precise, repeatable horizontal adjustments. Here's a pic of us using it to make a frame a bit larger than normal. I think it was about 24 x 80.
Hard to convey in words--a drawing is better I think.
The issue with this cut is that after the blade, there is no meat for the thing to stand on, really (tip of 14 degree angle) So fence extension is good, but really counterpressure after the blade in addition to the would be my nicest ideal I think...
oops! drew teeth of blade in wrong direction. We're not that crazy--our blades are indeed in the right direction lol
Clamp 2 2x4's against each side of the panel while upright. Set the bevel to what you need on a circular saw and either free hand or set up a fence for the circular saw. Since your angles vary slightly from job to job it probably wouldn't pay you to build a jig for this unless you could build the variation into the jig itself.
Build a router jig. Not that difficult. Basically a ramp with a sled accross the top. Building an adjustable ramp will accmodate various builds.
" counterpressure after the blade in addition to the would be my nicest ideal I think..."
If your drawing is accurate in concept, i.e. all material is being taken away by the saw blade, I would use an extended fence and a featherboard - on before and one after the blade.
You know I also wouldn't see a problem building a sled for the table saw to repeat these cuts since your angles only change a few degrees the same sled would work. Pretty straight forward the sled with a tall stationary fence moves the panel that is clamped to a taller fence thru the cut.
Thanks folks, all these options are better then my current two.
I'm very new at jig design so I appreciate the input.
In terms of fence extender--something like pic 1?
As for the featherboard, pic 2?
Then where I get stuck is how to mount the feather board mid table. On top of that accounting for height "x" (see pic 3 and pic in next post (3 per post limit)
So as how to mount this--might be a stupid question, but I'm stumped on how to do it without blocking outfeed. Is there hardware/special clamps for this, that I do not know about?
If you're actually getting a waste piece, using a featherboard will be a lot tougher.
Yes, you can block it up. In that case I would make my fence higher - at least 6", and up to 10".
The featherboard can be mounted in the miter slot. See pic below.
BTW, now having a good idea what you're doing, you don't happen to have a tilting arbor shaper do you? That would be the safest, slickest way IMO... Especially if it has a power feed (every shaper should have a power feed, by the way).
ooooo, there it is. Miter gauge slot hold down hardware, ordered. Thanks a ton!
As for the shaper--I do sure like slick and safe. We do have a beast of a high-tech shaper--collecting dust since the door maker retired and they started outsourcing doors. I'll ask tomorrow-only one guy knows how to use it and he is one busy grump.
Thanks again, that's gold!
PS--agreed on power feeds. I have a shaper at home and I sure do respect the thing.
If the shaper turns out to be nontilt I would use an adjustable angle cutter in the shaper to cut this. Lietz makes a nice one.
My mentor taught me to come up with 3 valid solutions to any problem I encountered in the shop. Often, he'd give me a job, and I'd ask how I should do it, and he said "you'll figure it out" and I would. Then when done, he'd say 'well, you could have done this, or you could have done that'. Drove me crazy until he said, just stop and think of 3 good methods, then make your choice on the parameters you need - safety, accuracy, availability of tooling, etc. I still do it all the time, and have taught everyone I work with.
Now you have at least 3 basic solutions, so you can think them through and determine which will be the fastest, the safest, the cleanest, the most accurate, the most versatile - whatever you need - and apply those parameters to your decision.
Jigged solutions in our shop get named after the maker. We have the "Angel" and the "Purciful" and others - so you have a "Mel" in the future. Be advised they may go thru 2 or even 3 iterations before all the bugs are worked out. In Indiana, we call it Evolution.
Jig making and design is true pure fun. So is machine tuning. Feels like a "master key" :)