Newbie RAS question

[mac davis]

This is going to be a very basic question, so please bear with me... all my experience is with table saws...

I finally got the new table and fence on the garage sale Power Krap RAS... after several tries, I came up with the right mounting/adjusting setup to be able to get the table square with the blade and cutting square in both directions.. (had a tough time getting the table "leveled" at exactly 90 degrees from blade zero"

I ran some sample cross cuts last night and all came out surprisingly square... must be the influence of this NG.. I now have a cool looking kerf in the table to line up cuts with and all is fine in THAT direction...

My question is in ripping... how is this handled in relation to the fence, as in moving it (adding or replacing filler strips) to adjust your cut without having a bunch if cuts in the table??

I'm sure that I'm overlooking something simple, but the concept of an upside down table saw that has the blade move and the work stationary is really strange for me.. and the new table is too pretty to screw up without asking how to do it right.. H E L P !!

Mac

[Doug Winterburn]

First and most important - don't kerf the table. Apply a 1/4" sacrificial top to the front table and make the "standard kerfs" in this. The standard kerfs include a 90 degree crosscut, a 45 degree bevel, a 45 degree miter and inrip and outrip troughs for ripping. The troughs should be made by pulling the motor all the way to the end of the arm, locking it on the arm and rotating the motor while the saw is running. The motor is then unlocked and pushed slowly to the fence for the inrip trough and pushed in to the start of the inrip trough when cutting the outrip trough. The Powr-Kraft sam troughs don't aligh, but many saws do. Here's a link to a picture of a sacrificial ply top with the standard kerfs on a Powr-Kraft RAS:

-Doug

[Doug Winterburn]

Also notice that all adjustments (except bevel) can be made without raising/lowering the arm. For miter cut(s), move the arm with the motor behind the fence. For rip cuts, pull the motor all the way to the end of the arm, lock, rotate for inrip/outrip, unlock the motor and move to the desired rip width and lock on the arm. For wider rips, use the outrip position and move the fence all the way back. you may also want to place a properly sized piece of 1/4" ply over the back table pieces to bring them level with the front sacricial top.

-Doug

[Tom Kohlman]

Long-time RAS user that has since moved on to TS for ripping...make sure the blade is exactly in plane with the fence, if in doubt make sure to err on the board leaving the fence after it clears the blade (i.e. a "pinch" between the blade and fence will get your heart going), be sure to use the kick-back prawls, wear those eye protection things and whatever you do, stay clear of the path that the board will want to take if something isn't exactly right (that would be in line with the path you are feeding it from).

I used the RAS as my only major tool for quite a few years and still think it is the most versatile tool made, you just have to keep it "tuned". The major PITA with the tool results from its versatility, too many angles to play with, every change in one potentially screwing up all the others. Recognize that flaw and pay more attention to safety than most other tools and you'll have some fun.

[Allen]

snip

snip

When you rotate the head 90 degrees for ripping, the saw blade will move so as to touch the table a couple of inches to the right of the curf you have already cut in the table. You only need to lower the blaed until is cuts into the table just a tiny bit. You do not move the fence to adjust the width of cut but rather move the blade/motor/carraige along the arm to adjust the width of cut. Only if you need a wider cut than can be made with the carraige fully extended do you move the fence to a more rearward position.

Adjust the width of cut with the blade slightly above the table and then lower it into the table when you are ready to rip. ALWAYS RIP BY PUSHING THE MATERIAL INTO THE ROTATION OF THE BLADE AND NOT WITH THE ROTATION. Also make sure guards and anti-kickback devices are properly adjust before ripping.

The damage to the table is the reason you should cover it with an equal size piece of 1/4" hardboard. That way, once there are "to many" curfs and cuts, you can just replace the hardboard cover and not the whole table. Attach the hardboard to the table with several recessed flat head screws. Make sure you place the screws where you cannot pass over them with the blace. This would be at the outside corners of the table and along near the fence except for a few inches either side of center where the blace can pass when set for miter cuts. Also watch for where the blade passes if you do a compound miter cut (arm to the right and motor tilted for miter cutting swings the blade even further to the right).

Allen in Sheboygan

[Rumpty]

Suggest you pickup a copy of the Mr. Sawdust book "How To Master The Radial Saw" for basic use of your RAS.

[mac davis]

Doug.. I understand MOST of that... i do have a 1/4' masonite top... but I haven't a clue what INrip & OUT rip are... they're marked on the arm of the saw but don't seem to correspond wit anything I can measure????

Mac

[mac davis]

Thanks, Allen... I actually understand everything that you said... hot damn!!

My neighbor claimed that you never move the saw head, only the fence and furring strips... that seemed kind of lame, as you'd need SO many different combinations of furring strips that you'd spend your whole life keeping the fence square to the table and blade...

Ripping is actually the main purpose for getting the saw... well, that and it was $50 at a garage sale...

Most of the cross cuts that I've done so far have fit on the CMS....

Mac

[mac davis]

Seriously, I'll check it out... never bought a book for wood or cars yet that didn't have at least 1 or 2 ideas in it that were more than worth the price of the book..

Mac

[Doug Winterburn]

Inrip is where the motor is rotated 90 degrees clockwise (looking down from the top) from and the blade is "inside" the motor relative to the operator. In the inrip position, the work should be fed from right to left against the rotation of the blade.

Outrip is where the motor is rotated 90 degrees counter clockwise and the blade is "outside" the motor relative to the operator. In the outrip position, the work should be fed fromleft to right against the rotation of the blade.

There should be inrip/outrip scales on the sides of the arm that give width of rip relative to the fence in the normal (front) position and all the way back (rear) position. These scales should have an adjustable pointer that can be set with the blade in the inrip/outrip positions and against the fence in the rear/front position for a zero setting.

Normally, the table comes in three pieces - front table, filler and rear table. They are usually kept in that order on the table and the two most common positions for the fence are between the front and filler table or all the way back behind the rear table. You can determine the proper combined width of the rear + filler table pieces by examining the difference between front and rear scales for either inrip or outrip.

-Doug

[J. Clarke]

Not meaning to rain you your parade but if you mainly are going to be ripping you'd have done better with a table saw of some sort. While a radial arm saw will rip just fine as long as you're careful and pay attention to what you're doing, you work a lot harder at it than you do with a table saw. On the other hand, for crosscut the radial arm saw rules.

That said, your neighbor doesn't have a clue with regard to the RAS. Doing it his way defeats the purpose of having the movable head.

Someone else has suggested the Mr. Sawdust book, I'll add to that a book by Jon Eakes, available only as an ebook or used unfortunately, but well worth the price--an improperly adjusted radial arm saw is one of the most frustrating things you'll ever deal with.

[mac davis]

cool.. now that you said that, I see my problem... I was thinking that you can only rip from one direction, (the "front" of the saw), and not thinking that the head can go to 90 degrees in either direction... Knowing this, I can see where you have more ranges of rip cuts without having to move out of you "fan kerf"..

Mac

[mac davis]

well, it got down to price and floor/garage space... right now, I have about 2/3 of a 2 car garage for a working and storage area..

the RAS was cheap and my goal was to quit using my trusty old shopsmith as a saw, and leave it in the drilling/routing position..

Agreed, you might work harder at rips with a RAS, but it beats the hell out of my old method, which was putting a sheet of plywood on sawhorses and using a metal guide and skill saw.. lol

We're still looking at houses with rv parking and a place to put up a workshop.. if we find one, I'll be looking into a full-size table saw, for sure..

Mac

[Rumpty]

Jon Eakes, available only as an ebook or used unfortunately, but well worth the price

Eakes book is excellent for alignment, but lacking in basic use etc. or the RAS. The Mr. Sawdust book is a very detailed book on how to use the RAS from basic cuts up to moulding and shaping operations.

[J. Clarke]

I agree--he should have both.