Dado Cuts

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gk777
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Joined: Sun Apr 06, 2008 4:03 pm
Location: Delaware

Dado Cuts

Post by gk777 »

Ok another question. Dado Cuts -

What is the RPm I should set for Dado Cuts, I have the shopsmith speed chart but it does not list dado. I assume the RPM should change for depth and width of cut What would be starting guide lines. The sho smith dial has dado with an arrow is this good enough for any cut and just adjust the feed rate based on the motor sound?

Should I make mulitple passes for a 3/4" deep. In other words change the depth of the blade or what is the max depth I should cut with each pass?

Also should the dado blade be sitting on the arbor threads? I do not think so. But I am having trouble with the lower saw guard, It is hitting the dado blade. I adjusted the hex stop screw all the way in on the lower saw guard (the one that allows the riving knife to align with the saw blade) and the blade still is comming in contact with the inner guard assembly. So then I installed a spacer and now the dado blades on the outside of my 3/4" cut is sitting on the threads of the arbor.
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wa2crk
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Post by wa2crk »

Hi;
I believe that the speed dial has an area marked "Magna Dado" and you should set the speed dial in that range. But remember that the actual speed is a subjective thing even for sawing. Speed can be higher for soft woods and slower for harder woods and also the depth of the dado also comes into play. Don't forget that you are removing a large amount of stock and the machine will tell you when you have the right speed. If the machine seems to slow down noticeably during the cut then either slow down the feed rate or the speed of the blade.
Masking a dado cut is a dangerous procedure because it is a "blind" cut and you can't where the blade is running or exactly where the exit of the cut is, so for this reason always use the push blocks when you make a blind cut of any kind. The purpose is to remove material from the wood and not from your hand. Always think safety!!!!
Bill V
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wa2crk
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Posts: 3080
Joined: Sat Jul 22, 2006 7:37 am
Location: Leesburg, Fl

Post by wa2crk »

Hi;
I believe that the speed dial has an area marked "Magna Dado" and you should set the speed dial in that range. But remember that the actual speed is a subjective thing even for sawing. Speed can be higher for soft woods and slower for harder woods and also the depth of the dado also comes into play. Don't forget that you are removing a large amount of stock and the machine will tell you when you have the right speed. If the machine seems to slow down noticeably during the cut then either slow down the feed rate or the speed of the blade.
Masking a dado cut is a dangerous procedure because it is a "blind" cut and you can't where the blade is running or exactly where the exit of the cut is, so for this reason always use the push blocks when you make a blind cut of any kind. The purpose is to remove material from the wood and not from your hand. Always think safety!!!!
Bill V
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wa2crk
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Posts: 3080
Joined: Sat Jul 22, 2006 7:37 am
Location: Leesburg, Fl

Post by wa2crk »

HI again;
I tried to edit my last post but it did not take.
I would not try to make a 3/4 in deep dado cut in one shot. 3/8 is the max that I would try. Then you can sneak up on the depth with a couple of more cuts. I f you are doing a lot of separate pieces borrow one of the depth collars from the lathe tailstock and put it on the front leg of the main table. Then when you establish the final depth of cut, lock the stop collar down against the table carriage and when you make repeated cuts the collar will not let you go too deep.
I have never noticed how my dado sits on the arbor but I do not think that if one of the blades sits on the threaded portion of the shaft that it would cause a real problem. I just use the arbor that SS sent with the dado package and went to work.
As for the blades hitting the saw guard check to see if the neck of the arbor is the correct length. The saw arbors are different for the 500 and the 510/520 machines but I am not sure about the dado arbors. I always thought that they were the same.
Let us all know how you make out.
Bill V
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