Question regarding Domino fence skew

[promark747]

Just bought a Domino, and have a question regarding the fence.  I have noticed a slight twist or skew on the right side.  This was present on all of the models at my dealer, so I don't think it is an issue unique to the one I bought.  When I got home, I took some time to get more familiar with the machine, and here is what I noticed.  First, there is a spring-loaded ball bearing on the right side that I believe is meant to keep light pressure on the fence as it slides.  More importantly, when the height locking lever is tightened, it applies force only to the right side of the fence/pillar.  When the locking lever is not engaged, the fence is perfectly parallel with the edge of the base (a ruler placed along the fence will contact the base and lay flat).  However, as force is applied to the lever, I can clearly see it push the fence proud of the base (about 1-2 mm I'm guessing), leaving a gap between the ruler and the base.  I don't think I am applying too much force, but will consider it a possibility.

I guess the question is whether this minor skew will affect the accuracy of the cuts (I have yet to make my first plunge) or if there is a trick to avoiding this twist.  I assume that one shouldn't crank down on the lever, and have seen a suggestion to press the left side of the fence against the left pillar while locking the lever (which actually seems contrary to the way I think it should be pressed...I'm thinking you would want to push the left side of the fence forward to mimic the way the right fence is moving when the lever is tightened.)

Based on the Domino's design, I would think everyone's machine has the same issue (or non-issue).  When I was looking at the DF700, I did notice that the height locking lever is designed differently, perhaps to avoid this uneven force.

In the end, I guess I should just start using my new Domino... ;D

Thanks,
Brian

 

[sancho57]

I have a hard time picturing what your talking about could you post a photo?

 

[promark747]

Here you go...the first picture shows the ruler nice and flat across the fence and base.  

[attachimg=1]

 

[promark747]

When I begin to tighten the locking lever, the fence becomes higher than the base, leaving a small gap (only on the right side of the fence where the pressure is applied).

[attachimg=2]

 

[mouppe]

Yes, I know exactly what you are referring to. My domino 500 does it as well, although it does not affect the mortise. I don't over-tighten it to avoid skewing it- just enough to stop the fence slipping during use. Good practice suggests you should check your fence has not slipped every few mortises anyway.

Moreover, when you are using the steps on the left side the skew doesn't occur as the fence is resting on the left side, and the lever tightens it on the right side.

 

[greg mann]

While I believe the difference looks much less than 1 to 2mm I think the important distinction here is that you WANT the fence proud. That way, you are actually sitting on the fence, which is the surface you want in registration as opposed to the much smaller surface that is now in recess.

 

[semenza]

   I had that problem when using the sliding stepped height setting gauge.  I never actually checked with a straight edge but did pick up a tip that  solved the issue for me. At least the skewed fence that was causing slightly skewed mortises went away in actual usage.

  Set the sliding gauge.  

  Drop the fence onto it.  

  Tighten the lever just enough to hold (don't press on the fence while tightening).

  Pull the sliding gauge out.

  Then tighten the lever fully.

    Best I can tell is that this procedure keeps the sliding gauge from holding the fence up on one side while the lever is tightened. The tightening seems to draw it down a tiny bit. Now I could be all wet on the why and how of this, but it certainly has worked for me in use. Like I said I never bothered to check with any measuring  device because it solved the specific problem I was having.

First generation, Domino 500.

Seth

 

[greg mann]

   I had that problem when using the sliding stepped height setting gauge.  I never actually checked with a straight edge but did pick up a tip that  solved the issue for me. At least the skewed fence that was causing slightly skewed mortises went away in actual usage.

  Set the sliding gauge.  

  Drop the fence onto it.  

  Tighten the lever just enough to hold (don't press on the fence while tightening).

  Pull the sliding gauge out.

  Then tighten the lever fully.

    Best I can tell is that this procedure keeps the sliding gauge from holding the fence up on one side while the lever is tightened. The tightening seems to draw it down a tiny bit. Now I could be all wet on the why and how of this, but it certainly has worked for me in use. Like I said I never bothered to check with any measuring  device because it solved the specific problem I was having.

First generation, Domino 500.

Seth

Seth,

My interpretation of the OP's question was that the condition showed up when the fence was upright and the Domino was plunging vertically in the face of the work, not when it was dropped down for using the Domino horizontally, as in the edge of the work. Maybe I am missing something but the picture looked like the fence was tilted up, 90 degrees to the centerline of the cutter.

 

[mouppe]

Greg, I didn't perceive the OP's problem to be as you interpret it but you appear to be right.

He wrote "When the locking lever is not engaged, the fence is perfectly parallel with the edge of the base (a ruler placed along the fence will contact the base and lay flat).  However, as force is applied to the lever, I can clearly see it push the fence proud of the base (about 1-2 mm I'm guessing), leaving a gap between the ruler and the base." (My emphasis.)

 

[semenza]

   I had that problem when using the sliding stepped height setting gauge.  I never actually checked with a straight edge but did pick up a tip that  solved the issue for me. At least the skewed fence that was causing slightly skewed mortises went away in actual usage.

  Set the sliding gauge.  

  Drop the fence onto it.  

  Tighten the lever just enough to hold (don't press on the fence while tightening).

  Pull the sliding gauge out.

  Then tighten the lever fully.

    Best I can tell is that this procedure keeps the sliding gauge from holding the fence up on one side while the lever is tightened. The tightening seems to draw it down a tiny bit. Now I could be all wet on the why and how of this, but it certainly has worked for me in use. Like I said I never bothered to check with any measuring  device because it solved the specific problem I was having.

First generation, Domino 500.

Seth

Seth,

My interpretation of the OP's question was that the condition showed up when the fence was upright and the Domino was plunging vertically in the face of the work, not when it was dropped down for using the Domino horizontally, as in the edge of the work. Maybe I am missing something but the picture looked like the fence was tilted up, 90 degrees to the centerline of the cutter.

Oh. yup, I see. Your interpretation is correct.  For those reading ... my previous post might help solve a different fence problem.

I just checked on my Domino for the OP's  situation. I have the same gap on one side of the fence (as shown in the pics) but the other side is flush. On mine it stays the same whether the lever is tightened or loose.

I have been using it for quite a few years. Never noticed the gap and as far as I can tell it doesn't cause a problem with the mortises.

Seth

 

[sancho57]

For me, If something doesn't affect the accuracy or functionality of a tool, I dont worry about it.

To tell ya the truth, I dont take straight edges and examine my tools as long as they do what their supposed to.

 

[promark747]

For me, If something doesn't affect the accuracy or functionality of a tool, I dont worry about it.

To tell ya the truth, I dont take straight edges and examine my tools as long as they do what their supposed to.

I hear ya, but I view it the same as setting up a table saw or other tool where you want to make sure the basic parts are aligned properly (sometimes to within a couple thou of an inch).

After doing some extensive reading on older Domino threads here on the FOG, I think the height locking lever mechanism is probably not an ideal design, as 1) the fence can drift without just the right amount of pressure -- as evidenced by users who file the posts, attach sandpaper, or simply crank down hard to increase friction, and 2) the one-sided pressure applied to the fence will inevitably cause some amount of skew.  Having said that, I'm hoping the skew is minor enough to not cause any issues.  

 

[promark747]

   I had that problem when using the sliding stepped height setting gauge.  I never actually checked with a straight edge but did pick up a tip that  solved the issue for me. At least the skewed fence that was causing slightly skewed mortises went away in actual usage.

  Set the sliding gauge.  

  Drop the fence onto it.  

  Tighten the lever just enough to hold (don't press on the fence while tightening).

  Pull the sliding gauge out.

  Then tighten the lever fully.

    Best I can tell is that this procedure keeps the sliding gauge from holding the fence up on one side while the lever is tightened. The tightening seems to draw it down a tiny bit. Now I could be all wet on the why and how of this, but it certainly has worked for me in use. Like I said I never bothered to check with any measuring  device because it solved the specific problem I was having.

First generation, Domino 500.

Seth

Seth,

My interpretation of the OP's question was that the condition showed up when the fence was upright and the Domino was plunging vertically in the face of the work, not when it was dropped down for using the Domino horizontally, as in the edge of the work. Maybe I am missing something but the picture looked like the fence was tilted up, 90 degrees to the centerline of the cutter.

Yes, to clarify, when the lever applies pressure, the right side of the fence (as it sits in the upright/closed position) gets pushed out and creeps proud of the base.  This would--in theory--make the cutter not perpendicular to the workpiece (in cases where you are plunging straight down into the face).  Similarly, if the fence were to be flipped down (in order to plunge into an edge or end), the cutter would not be co-planer with the workpiece.

 

[greg mann]

   I had that problem when using the sliding stepped height setting gauge.  I never actually checked with a straight edge but did pick up a tip that  solved the issue for me. At least the skewed fence that was causing slightly skewed mortises went away in actual usage.

  Set the sliding gauge.  

  Drop the fence onto it.  

  Tighten the lever just enough to hold (don't press on the fence while tightening).

  Pull the sliding gauge out.

  Then tighten the lever fully.

    Best I can tell is that this procedure keeps the sliding gauge from holding the fence up on one side while the lever is tightened. The tightening seems to draw it down a tiny bit. Now I could be all wet on the why and how of this, but it certainly has worked for me in use. Like I said I never bothered to check with any measuring  device because it solved the specific problem I was having.

First generation, Domino 500.

Seth

Seth,

My interpretation of the OP's question was that the condition showed up when the fence was upright and the Domino was plunging vertically in the face of the work, not when it was dropped down for using the Domino horizontally, as in the edge of the work. Maybe I am missing something but the picture looked like the fence was tilted up, 90 degrees to the centerline of the cutter.

Yes, to clarify, when the lever applies pressure, the right side of the fence (as it sits in the upright/closed position) gets pushed out and creeps proud of the base.  This would--in theory--make the cutter not perpendicular to the workpiece (in cases where you are plunging straight down into the face).  Similarly, if the fence were to be flipped down (in order to plunge into an edge or end), the cutter would not be co-planer with the workpiece.

The cutter is never perpendicular to the workpiece except at the center of its arc, which is a momentarily fleeting event. The only lack of perpendicularity you will experience will be in the PLUNGE PATH of the cutter, which could only be measured along either end of the resulting mortice, And, it would be a function of plunge length compared to the base. If your base is out of perpendicular to the rods upon which your travel takes place by .5mm over its full width (about 100mm wide maybe?) then a 25mm plunge would be out .5mm/4, or .125mm (.005"). This will be in the dimension that is least important and probably an order of magnitude more accurate than most mortices chopped out with a chisel.  [wink]

 

[Paul King]

I noticed the same thing with my Domino500 and sent it in for service - they said that the vertical face is not calibrated to be flush with the work surface - they are only worried about the calibration of the horizontal surface of the fence when dropped down.