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Jesse Espe
10-10-2006, 8:18 PM
I've posted a few times and lurked A LOT. Time for me to ask the experts - you guys!

My dilemma: I have a DW708 SCMS that isn't cutting quite right. I've verified with my Starret Combination Square that the fence is square to the deck, as well as the blade square to the fence and the deck. I have a 12" Forrest Chopmaster (1/8" kerf) and have an Irwin laser guide installed (which I'm ready to chuck into the river).

I was cutting 11" wide boards and noticed that while the corner nearest the fence ended up cutting square, the corner on the opposite edge was off. Anybody else ever see this? Should I be squaring the blade with the slider all the way extended?

The only thing I can think of is that the error is so small when viewed at the fence, but amplified over the course of 11 inches or so.

Any help you can give me to help restore my sanity would be greatly appreciated. Thanks!

Richard Wolf
10-10-2006, 8:30 PM
Well it sounds like the saw is cutting square to the fence, are you sure the board is uniform in width to begin with?
Also, you must square the blade to the fence, the blade square to the table, and the blade square for the full lenght of travel. Also make sure the fence on both sides of the blade are inline with each other. I know it is one piece, but pressure when tightening the bolts can twist them.

Richard

Perry Holbrook
10-10-2006, 9:05 PM
Yes, you need to square the blade to the fence for the entire length of travel. Sometimes easier said then done.

Perry

John Fry
10-10-2006, 10:34 PM
I'm with Richard on this. Are you sure your board's width is true? IOW, are the edges perfectly parallel?

I have that same saw, same blade, and my saw will cut true across that size board everytime.

Jesse Espe
10-10-2006, 11:08 PM
John and Richard,

I would like to think that the board's width is true. Face and edge jointed , then ripped to width on my TS (Delta hybrid w/ Biesemeyer fence). I checked the width all the way along the length of the board for consistency, then ran it through the planer.

I'll try squaring the blade to the fence along the entire length of travel tomorrow. I was voluntold for an all-nighter at work tonight, so not much playing around in the shop tonight.

Thanks for the constructive responses so far!

Jesse

Jason Roehl
10-11-2006, 7:58 AM
Try investigating your cut technique as well. Out, down(chop), in, making sure you don't go too fast or put ANY pressure to the sides. Every time I go in a tool store, I check all sliders fully extended to see if there is any flex--they all flex, so it is possible on any slider to introduce cut error with sideways pressure while cutting. I have a 708 as well, and if I get sloppy, wide cuts can have trouble.

Another possibility is that the board is moving slightly during the cut. Mitersaw blades can be "grabby".

Bob Childress
10-11-2006, 7:59 AM
Jesse, this may not help and will certainly expose me to ridicule but I have the 708 and noticed one day that I was having a similar problem to yours. I fumed and fumed and fussed. :mad: After several cruddy cuts I happened to "notice" that the miter guide had somehow "slipped" to 89 degrees. :o :o Pushed it back into the slot and problem solved.

Frank Howell
10-11-2006, 6:39 PM
Hey Jesse,
I have the same saw and the same problem. No matter how much I try to square, it's either off at one end or the other. I'm managed to correct this more with technique than anything else, as I believe it to be an error in the slide rails, and the amount of play in the bearings of your slide.

Mine is only off by about a degree or so toward the left. As I usually stand to the left and operate with my right hand, I find it pretty easy to just keep a little side pressure to the right as I make any sliding cuts. It's still not perfect, but usually gets me close enough.

Get your self an el-cheapo piece of pine about 10" wide and play around with your techique. Cut one normally, then try one to the right then one pulling to the left. Check those and see what you get.

Good luck and let us know how it goes.

Dale Thompson
10-11-2006, 9:01 PM
Jesse,
Try cutting with a VERY light touch on the handle. Many people use a "white knuckle" grip because they are "holding" the blade and are a bit concerned about it getting away and "biting" them. :eek: As with a RAS, this is guaranteed to give you a bad cut especially when you get to the end of the arm (or maximum rail extension) and the potential torque is the greatest. :)

Dale T.

jud dinsmore
10-11-2006, 10:23 PM
i second frank's observations with the head of the saw having "play" from side to side. i had the makita 10" slider and couldn't cut straight with it despite several adjustments to the scale and fence. it was more noticable when i stood material up to cut 45's. very frustrating. i would recommend building a crosscut sled for your table saw. results will be much better. good luck.
jud

Jesse Espe
10-11-2006, 11:53 PM
Thanks for all the help so far. I was home long enough to check the fence sides for alignment with each other (they were) and the blade square with the fence with the slider all the way extended. Initial measurements showed it was off, but I wasn't sure if that was because the combo square was up against the blade teeth and that was causing the apparent deflection.

I was too tired to fiddle with it, and six hours later, here I am back on night shift. If I get off of work at a decent hour today, I'll take a better look at the blade alignment and also look into how much lateral play is in the slider.

Jud, I don't disagree with you regarding the crosscut sled. It's on my "to-do" list. My problem is that I'm a "find it-fix it" kinda guy. I truly believe that if you pay a significant amount of money for a machine like the DW708 or any machine for that matter, than it should work as advertised. If it doesn't work, I have to fix it. Hence, my current sanity deficiency.

Once again to all, thanks for the input so far. This is why I like the Creek so much - a wealth of knowledge, and most all of it constructive in nature.

Jesse

Jesse Espe
10-22-2006, 11:55 AM
It's been a long week and change, but I finally got around yesterday to adjusting the SCMS.

When I used my 4 inch engineering square, everything appeared fully squared up. I then decided to use my Starrett 12 inch combo square to verify the blade square with the slider fully extended. I found that with the slide fully extended, the blade was off square slightly. I verified that the blade was off by adjusting the position of the combo square such that the ruler portion of the sqaure came along side the blade between teeth (this required the use of a quick-acting clamp to hold the combo square flat against the fence) I adjusted the blade per the instruction manual, and now it's cutting 11" boards dead on.

I did notice the side-to-side play that was mentioned previously. Looks like its coming from somewhere in the trunnion assembly. I have a feeling that if I start taking that apart, I'll be asking for more trouble than it's worth, so I'll just settle for proper technique and go from there.

Thanks to all who helped!

Mark Rios
10-22-2006, 12:05 PM
Glad you got it worked out Jesse. I loved my 078 and I still kick myself for selling it and I'm trying to find another new one. I've found a couple but the companies were asking close to full MSRP for them. I'll wait a little linger.

What I wanted to mention though is the two (I think there is two) set screws on the side of the slide tube carriers. I was having a little trouble one time with my cuts being a little squirrely. After looking around the saw for awhile I found these screws. I adjusted one of them and got all the movement out of my tubes.

Just wanted to mention.

glenn bradley
10-22-2006, 12:36 PM
This may be obvious but, just trying to help. . . plus, I've done it. After you make your cut I assume you are checking for square by measuring the cut vs. the side of the board that was against the fence. Then I assume you are checking the "away from fence" surface of the cut against the "away from fence" surface of the board. Could the board edges be out of parallel? That is "fence side" vs. "away from fence" side.

Jesse Espe
10-22-2006, 2:42 PM
Glenn, that's happened to me in the past, when I had a Delta Shopmaster TS. The fence was very squirrely and caused all kinds of havoc with ripping boards to width. I would constantly have to check and recheck the width of each board I ripped.

I did two things to remedy that. First, I bought a Delta Hybrid with the Biesemeyer fence. Second, I bought a solid combination square. Now I know that just about anything I rip, given a solid, square jointed edge/face, will have two parrallel edges. I check every time just out of habit.

Jesse Espe
10-22-2006, 2:44 PM
Mark, I think I know which screws you are talking about, or at least their general location. I'll give it a shot.