Domino Calibration

[Jeff Wright]

I am unable to accurately calibrate the Domino's sight glass used to mortise freehand. I have tried moving the sight glass left and right with no success. I've moved the sight glass all the way to the right, all the way to the left, and points in between. Before making any changes to the machine's calibration, I did 8 test cuts where I drew a line between two adjoining pieces of wood (as if you were doing a rail and style build). All 8 cuts had the upper pencil line on the right versus the line on the bottom piece, showing that the error was not in my technique. Do you have any secrets about how best to adjust the sight line precisely? My only current solution is to not use the tight mortise setting at all when doing freehand but instead set it to the middle setting for the slot size and manually adjust the alignment of the wood pieces. Thanks.

 

[Tezzer]

Jeff the trick i found was to stop the sight glass from moving when the screws were tightend. Because the screws just sit on the plastic it wants to naturaly move with the monentum of the screw head being turned.

Solution i found was to put two boards together and mark a pencil line across, and plunge the Domi on each mark with the line on the gauge exactly on them. When you join them together you will see how far out the pencil line is, then its just a matter of re adjusting.

It may take a few goes but the trick is to put a scratch awl in the bottom edge of the hole and hold it tight as you tighten the screws. That will stop it moving a fraction. Hope that works for you like it did for me  ;D Keep us posted

 

[Jeff Wright]

Jeff the trick i found was to stop the sight glass from moving when the screws were tightend. Because the screws just sit on the plastic it wants to naturaly move with the monentum of the screw head being turned.

Solution i found was to put two boards together and mark a pencil line across, and plunge the Domi on each mark with the line on the gauge exactly on them. When you join them together you will see how far out the pencil line is, then its just a matter of re adjusting.

It may take a few goes but the trick is to put a scratch awl in the bottom edge of the hole and hold it tight as you tighten the screws. That will stop it moving a fraction. Hope that works for you  ;D Keep us posted

I'm not clear on what you are doing with the scratch awl. What hole are your talking about . . . one of the screw holes holding the plastic sight gauge on? I have already tried holding the plastic sight gauge very tight as I tighten the two screws.

 

[Tezzer]

On the sight glass, their is a red line and a hole through it. In that hole i put my awl and press it in hard and that stops the plastic moveing when i tighten the screws.

It took me only 2 adjustments that way and mine is near perfect in alignment

 

[James Metcalf]

Jeff

What Tezzer has told you is spot on, but if your calibration mark on the plastic will not move far enough to the left, if I understand you right.Then you may have to take a hand file and remove a slight amount from the plastic that the calibration marks are on. This was what I had to do.I few slight strokes with the file and it was spot on.

 

[Jeff Wright]

On the sight glass, their is a red line and a hole through it. In that hole i put my awl and press it in hard and that stops the plastic moveing when i tighten the screws.

It took me only 2 adjustments that way and mine is near perfect in alignment

Mine does not have the red line or the hole your refer to . . . only the many black lines. Wonder if you have a different version?

Here's an interesting question: I notice the center sight line does not line up with the line scribed on the base. Does that mean that if those two lines are not aligned with each other you could run into alignment difficulties? Say if you finally adjust the plastic sight line to make good cuts, BUT that line does not fall in the same line as the scribed one in the metal base. Hmmmmm.

I have tried using feeler gauges to incrementally move the plastic sight glass without success. I'm wondering if the screws have maybe imprinted their heads into the plastic and want to fall back into their original position when I go to tighten the two screws. Don't know for sure. But so far my best success has been to quit trying to adjust the sight gauge and instead lay my plastic sight gauge line a smidgen to the right of my scribed pencil line on the workpiece. I do this for each of the two cuts. This is not precise but it has allowed me to get somewhat close alignment . . . not in my opinion a long term solution . . . doesn't give me confidence in accurate repeatabililty.

 

[Jeff Wright]

OK, I got it! For anyone else challenged with this adjustment, here is how I did it. I ran a test cut to determine which direction the plastic gauge had to be moved. Note: Be sure to look at the gauge in the same direction as shown in Jerry's preliminary instructions; don't make the same initial mistake I made by looking at it from the other direction and as a result I moved the sight gauge the wrong direction.

I then loosened the two screws but not enough to allow the plastic sight gauge to slide freely. This allowed me to insert a thin razor knife blade between the one end of the site gauge piece and the metal housing. I then carefully twisted the knife blade to push the sight gauge to the desired direction, but only slightly. I then tightened the screws, made a test cut, made another adjustment, and it was spot on.

 

[mot]

Is there an ideal tenon size/cutter to use for calibration, or should it not matter?

 

[Dave Rudy]

I havent done calibration yet, although I have used the Domino to make a few mortises,The smallest tenon is the snuggest in the mortise, so I would believe that the tolerances are the tightest and therefore the calibration using it would be the most precise.

 

[ejantny]

My Domino mortises correctly. I notice on the sight plastic that the hole in the center is not centered with the center line in the plastic.

This got me to think that maybe people who are having alignment problems can try taking the plastic and flipping it end for end to see if this corrects their problem before filing the ends and enlarging the screw holes.

 

[Ted Miller]

As soon as I got the Domino and broke out some stock and tried my first mortise then inserted the tenons and the fit was not flush on the edge or face. I thought, uh oh, what did I do wrong. Then I looked at Rick's manual and made some adjustments to both the position gauge and the eccentric bushing on the locating pin was way off in the wrong direction. I thought I heard that each tool is run and inspected but of course they are not fine tuned. But now it works with zero hitches, everything flush and even on every mortise unless I move the machine while cutting...