Euro Slider Adjustment Question

[Larry Fox]

Wondering if I can tap into the collective wisdom of the group to help me figure out how to make this adjustment to my saw. I have an older SCMI SI12 sliding table saw and the wagon is in need of adjustment and I am not quire sure how to go about it due to what I perceive to be a lack of adequate reference points. I have verified that the wagon is set correctly height wise relative to the cast iron table. However, I need to adjust the tracking as it it running very slightly into the blade as the wagon travels past the blade. Ideally it would run parallel or very slightly away from the blade as it travels. I think the proper term is free cut but not sure of that.

How have others with sliders made this type of adjustment? I have a good compliment of measuring tools: feeler gauges, dial indicators, OneWay Multi-Tool, large(ish) precision squares, and a 24" straight edge. What do you use as a reference point? I don't think that I can use the blade-side edge of the slider wagon relative to the blade as I don;t think this is straight. It doesn't look like a precision cut edge to me. I don't think I can use the slot in the slider as I don't see an easy way to index to it.

Confused but I am sure I am missing something as I suspect this is a fairly common thing to do on these saws - especially at initial setup.

Thanks in advance for your time.

[joe milana]

Hey Larry, there is an active thread over at the yahoo MM forum right now on this topic. What you will learn for sure is that this is an exercise in patience & frustration at times. First confirm that your saw adjusts via the wagon, and not the cast iron top. I suggest since it sounds like your saw is close, just use a long (6'?) straight edge laid up against the blade and mark a reference point on the slider near the end of the straight edge, with tape perhaps, or just a pencil mark. Loosen the adjusting bolts & make a SLIGHT adjustment, then tighten things up & test. Use a cut to verify the squareness & repeat the process until you are satisfied. I hear claims from guys of getting their sliders within .0005 over the 8 or even 10ft length, but I think its Bovine Satire. Remember, once you adjust the wagon, you need to adjust the crosscut fence, and the rip fence, etc. Can seem like an exercise in futility at times...

[ian maybury]

Hi Larry. The closest i've seen to a step by step is the 'Survival Guide' by David Best on the Felder Owner's group. He's writing about Felder saws, but the principle is likely the same: http://www.cafepress.com/davidbest.14337605 Cheap its not...

The complexity depends a lot on how many support bolts the slider sits on/how long it is. Short sliders with only four are relatively easy - 8ft sliders less so because the pairs of bolts interact with each other. If you were going to try to align from the edge of the slider and are not sure it's right you would first need to verify that it's straight and parallel to the line of travel of the slider - since it's the latter that needs to be correctly aligned with the saw blade. You could mount a dial gauge on the saw table touching the slider edge, run the slider past it and see if it's showing significant wobble or misalignment.

In practice you may not need to worry about it unless you use it to measure from to set up cuts. Just clamp the base of the dial gauge on the surface of the slider, and clock from tooth to tooth on the saw blade (mark a tooth, and clock off it in 180 deg opposite positions to overcome the effect of any misalignment in the saw plate) - this will show what toe in/out you may have relative to the line of travel of the slider which is what you need.

The clearance in the slider bearings needs to be set correctly before setting anything else.

To adjust the toe in/out tap the slider in or out at one end having first loosened all of the bolts. (presuming your saw is as Felder) Do this carefully while holding the upper of the pair of locknuts and the bolt fixed with a spanner, and you won't lose your height adjustments by very much. It gets a bit awkward when it comes to re-tightening the bolts, as you have to simultaneously maintain the toe in/out setting while adjusting the table height and levelling. Some saws have jacking screws to adjust and then hold the toe/in/out - so you then only have to get the top surface of the slider in alignment with the saw table.

Hard to explain a process here, but i've levelled, aligned and set the height of my slider by completely loosening the outboard bolt pairs, and then getting the table level and at the right height working with three of the four centre bolts. (easy to level on three) Then ease up the fourth, and tighten the four when correctly aligned. (usually requires several iterations as the thread pitch is typically very coarse)

Once the centre four are correct and done up tight (and slider height/levelling/the toe in/out are simultaneously correct) then it's a case of adjusting the outboard pairs of bolts to bring both outboard ends of the slider into the same plane. A precision spirit level and a long and rigid straight edge is useful. You may find as well that some compromise is required in the form of dropping the four centre bolts a hair (especially if there is any slop in the slider bearings), in that when the slider is fully extended or retracted the overhang will tend to cause drooping and/or kicking up of one its ends.

You'll need before all of this to choose a target height for the slider above the saw table. I prefer a few thou, because it means the work is largely supported right to the blade. Bear in mind though that (a) if you are cutting sheet material that droops under its own weight that it may (unless held up by hand) catch the leading edge of the saw table as you feed it on to it, and (b) rigid or less than flat pieces may run aground - or even flat stuff on a high spot on the saw table if in fact the latter is not very accurately flat and level. Probably for this reason most makers recommend setting the slider considerably higher above the saw table - ref your manual.

[Steve Jenkins]

Not sure on your SCMI as I have an altendorf but on mine the slider mounts to its own support base that is fastened near each end to the saw casting. There is one large bolt at each end that you loosen then there is a smaller bolt laying horizontally that you use to pull or push the whole slider assembly toward or away from the fixed table and blade.
Not sure if any of that makes sense. Hope so

[Chris Parks]

I have never done it but the first thing I would be doing is getting a pair of lasers and setting them up referenced to the arbor/blade axis. Playing around with straight edges, indicators etc seems like a quick way to the funny farm and would grow old really quickly.

[Joe Jensen]

I have a Felder with a 10 ft slider. The very best way I've found is to use a Starrett Master Precision Level. This is the kind of level that machinist use to level precision metal machines. The one I have has 4 graduations on either side of level and each graduation is .0005" per foot (not .005"). The other key tools are a precision 4 ft straight edge and feeler gauges. I use the master level to make sure the cast iron top is adjusted really flat. When I first got my machine I used a straight edge to check the cast top and it seemed really flat. I had tons of trouble getting the slider right. A friend brought a precision master level and we found that my cast iron top had a .010" twist in it. Once we adjusted the cast iron to be really flat everything fell into place easily.

Steps:
1) get the top really really flat. I use the precision master level
2) On the Felder I loosen the bottom nuts on each stud that holds the slide in place. This loosens the slide but it doesn't drop. The upper nuts hold the slide up. You will find that even how tight you snug the bottom nuts will move the slider position by several thousands of an inch.
3) I have 8 studs on my machine. I position the slider in the center of the studs and I get it as close as I can. To do this I use a 4 foot straight edge and compare to the cast iron. Moving the inner and outer nuts will change the tilt of the slide relative to the cast iron. Also, when you move one of the four outside nuts the entire slide will change. Say you want to move raise the outside nut to raise the outside front. That will move the opposite corner down.
4) after maybe 50 adjustments and measures I have the slide where I want it. Then I move the slide to center the ball bearing cage between the front studs and the next set of studs. and I do the same thing. But I after and adjustment I move the slide back to the middle to see what the adjustment did. I may or may not keep that adjustment. repeat lots
5) Same thing for the other end.

After about 4 hours I was able to get my slider to be .005-.006" above the table for all but the last foot or so of slide on each end. I suspect the slider is not that flat. Having said the my machine drifted over time and it's now quite a bit different and it still functions great. Don't get as crazy as I did. Also if you don't love this kind of thing and have some OCD tendencies find a friend who does to help.

[Steve Rozmiarek]

Larry, is your slider mounted on bolts like the felders? The outrigger can also influence the slider, it can cause it to twist at one end of the stroke. A twist could cause the slider to track closer to the blade. When I went through mine initially, I found a dial indicator to be my favorite measuring device. Like Joe, I got it all level, then things started to make sense. Disclaimer, I like messing with this stuff, the saw was perfectly usable as it was.

[Larry Fox]

Thanks for the replies guys. I have not really dug in too deeply yet to know how the slider attaches / adjusts so I can't really give good answers to some of the great questions posed here yet. I just know that it is in need of adjustment and in starting to look at it and think about the issues I might encounter prompted my questions because it is not at all obvious to me how these adjustments might be made. To make matters worse, the manual for this saw is beyond awful. I am pretty sure it was written / illustrated by a pre-kindergarten child.

[ian maybury]

Even if the arrangements on your saw are a bit different you're probably getting a flavour for what's involved Larry. Truth be told there's no magic - but it's a job that really rewards having the right kit (the previously mentioned precision level, straight edge and saw gauge) and lots discipline. As in being very clear on what you are doing, in what sequence and why. A few unthinking try and see what happens moves and you will likely find yourself in the wilderness.

Heavy handed and unthinking swinging out of a spanner on the bolt sets risks doing no good to your slider too.

As Joe there can be quite a bit of iteration involved given that the coarse threads mean that even tightening has significant effects.

The good news is perhaps that the part of your work being cut is typically attached to only a very short length of the slider - so that even if despite your best efforts the extreme ends of the slider lift/droop a little at the extremes of movement it probably doesn't much disturb the cut.