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Reverse Table Saw7/20
I currently have a left and a right tilting tilting table saw but might have to lose one of them. Am I crazy to assume that I could swap legs on my 3 phase saw so it runs in reverse, mount the blade backwards, and do my opposite cut with material entering from back of table saw ? Say for cutting sill horns ? Mr Sochar ?
If you reverse the blade direction the nut holding the blade on the spindle would be subject to loosening. not the best safety idea.
I would expect the blade/arbor nut to loosen
The spring washer will help hold it. Find another arbor nut and double nut it.
Keep in mind that we run shapers in the wrong direction all the time. The nut and washer keep it on.
I would guess that all of us have over tightened a table saw blade to the point where you are thinking you might bend the blade or break a tooth trying to get the nut off. Two nuts would lock it in place.
I would be most concerned about the switch as Richard mentioned.
Which saw are you going to keep? I definitely prefer left tilting.
Its not just the bolt retaining the blade but also the fixings for the pulleys that are handed for rotation, it might work in the short term but the risks of something catastrophic happening are pretty high, in the situation that something does go seriously wrong an insurance claim against your business will negate the need for a saw in the future.
It might be easier to ask - How do other shops cut sill horns? You should get good answers and avoid going into experimental ground with what could be a problematic trajectory.
We cut sill horns, left and right, flat and canted, with a 14" band saw. A good blade on a tuned saw will give excellent cuts. We also have good outboard supports for the other end, or people work pretty good for this. In fact, we will often cut the sills to length at the same time, same saw. We draw the cuts on the face at one end, and bottom at the other end, making adjustments for the cant or bevel, and get it all done by turning on the saw once. If we have several, we will tilt the table left or right. Often, it is just eyeballed for tight on the upper face.
Aluminum sills are done with a jig saw, no tricks there.
I am all for finding new ways and experimenting, but I try to keep it reasonable.
The horns on a sill is a poor reason to use two saws. Its not like its saving you any time. If anything you are moving parts around to two different saws, when you can simply move the fence one saw.
Many people like David use the bandsaw for sills. The surface quality of the cut doesn't really matter because its all buried. As long as its accurate, its all good.
The #1 thing I like to have left & right saws are for cutting the angles on crown. We do it on the molder now so its a nonissue for us.
I'm drifting from the original question but I have to ask , how do you do your crown angles on a moulder? Do you have any pictures of your setup ? I have a scm compact nt moulder , I had knives cut ( left and right ) to try and do this and couldn't get the out feed fence to work properly . It was going under the bevel.
Sorry Adam, faulty example. The difference between the shaper and the saw is that the shaper has a keyed flat washer under the nut that prevents the torque & friction of the spinning cutter from spinning the nut loose.
On the table the nut and washer spin counter to direction against the blade to stay tight.
Not a good idea
More than just your modest humble opinion Steelie - you are dead on right on all points as not previously mentioned.
I can't remember anyone in 15 years on WW asking the reverse TS question, so either its not smart or not necessary.
I remember seeing a pic of someone with opposing left/right Unisaws sharing one long Beismeyer fence/table.
I have done this one time, when an architect wanted the maple risers of a staircase to miter into the exposed open maple stringer. Of course the saw in the shop tilted the opposite direction of what I needed.
What I did was to get another table saw arbor nut and use it as a jam nut on the arbor. Reverse the blade, and the two legs of the 3 phase power, and be mindful of what you are doing and put it all back after you are done. Put an enormous sign on the saw should you need to leave it before the operation is complete.
I believe that on almost all cabinet saws (Powermatic 66, Delta Unisaw, etc.) the pulleys are keyed and held with a set screw, so there are no rotational issues with respect to a component unthreading itself because of reverse rotation. You may want to be sure of that before proceeding.
I would think for most uses, if you have a Biesemier fence or Unifence, the rails allow for limited use of the saw on the left side of the blade, such that you could cut complementary/supplementary angles with the opposite tilt.
Hope this helps. Good luck.
My last, and most abusive, boss demanded that I reverse the feed of our 5 head Weinig one day. He had some odd idea that the flow would work so much better if it ran the other way. He wanted a stick to go in the gang rip, then directly into the molder, no lag time, then to the clean up saws and tally table, and on into the racks.
If you have ever watched a molded or more than 10 minutes, you can see how this idea of continuous feed would slow the process, not speed it up. Reason aside, he pushed on.
Now, for 5 years, he had been making big bucks with that machine - as he told me, a clean nickel a foot, every foot, every day (over $500,000 for the math deficient). And now he decides that feeding it backwards "won't be hard", and that I should do it. I went away, determined to come back with at least 25 sound reasons as to why this is not a good idea. Forget the rant about stupid hillbillies..... This was a man that was one of those gawd-awful "self made millionaires" that learned how to profit from intimidation. So no one ever told him no. That, and he was stumbling drunk by 10AM every day.
Of course, my favorite thing to do was say "NO", but then just as quickly, I'd say I will come up with a solution. I was burned out before the molder reversal, so it pretty much took me over the edge. The next meeting, he mentioned the idea, and I laughed out loud and told him I had no idea he was serious, that only a really ignorant fool would ever try such a thing. I walked out the door a few days later, never to return.
He did get my assistant to try to do it, and then he lost interest, moving on to harass some other sorry individual with some crazy project.
Was the molder reversal about "climb cutting" in an effort to try to get a "cleaner cut", or was it more of a time/motion "solution" to try to eliminate wasted steps with each stick of molding?
I would think molding of any size (large crown) would just get spit out back at you.
Nothing to do with climb cut. He was unable to understand anything beyond the basics. I do recall hearing about some nasty happenings when they did try a few things. Just like the tablesaw that the OP discusses, it is just not the way things should be done.
We were very successful with moldings - learned to make a great product, and rode the wave of change as Poplar took over from Western Pine in the early '80's.
Thank you everyone for your collective wisdom. For the record it is a direct drive saw so no pulleys to consider. I have always especially appreciated Mr. Sochar's viewpoint and experience with sash and door. His suggestion for doing the cuts on the Bandsaw will be on the top of my list to try. I have a habit of thinking of Bandsaws as rough cutting ( vs. finish cutting ) machines and I need to appreciate their finer aspects in spite of my laziness in tuning them up to their true potential.
If you want to learn how to set up your band saw so it will cut, watch this video. There is a wealth of information in it.
Band Saw Clinic with Alex Snodgrass