Making my first panel gauge and have a few simple questions

[Matthew N. Masail]

I don't know how one would work comfortably without a panel gauge, every time I need to score something wide I wish I had one. I've started making one, I'm planning on doing it simple, with a wedged arm and wedged blade. I like a wedge in a marking gauge as I find it comfortable to make fine adjustments with a plane hammer. just before I started I looked up some pics for a general feel and noticed 2 things:

1. triangular arms...? My thought it that a well fitted rectangle should hold it's setting perfectly, so why do something else aside from the cool look?

2. the rabbet on the bottom... most of the ones I've seen online have this, does it really help when marking wide boards? not that it's hard to do or anything just wondering about the function. seems to me one would have more control over the cutting angle of the blade without the rabbet.

[ian maybury]

I've never used one Matthew (i have various Shinwa rules with stops fitted), but I'd imagine that the rabbet stops the relatively heavy 'fence ' on the gauge from rotating - that's dropping down to one side or the other past the edge of the board it's running against while in use. The horizontal face of the rabbet can run on the top surface of the board, and hence provide support. It means you can't as you say tilt the blade as on a small marking gauge, but most use round ended or circular knives that presumably don't need this. it would eliminate the need to control this movement in use too.

Not sure what you mean by triangular arms - maybe the placing of the beam corner down so that it appears as having a diamond section? This is possibly because most like this seem to use a screw clamp in the vertical with this beam placement - that is bearing on the top corner of the diamond via probably a 90 deg 'V' shaped pad. The benefit of this is that the lower corner of the beam is pressed by the screw into the bottom 'V' or corner of the square/diamond shaped opening in the fence. Meaning that when clamped it's simultaneously aligned/supported by two faces of this square opening - with the result that if the sides of the opening are square then the bar will be square to the fence in all directions. It also means that the bar need not be a really close fit in the square opening to achieve this accurate alignment. If the clamping screw was placed mid one of the flat sides then the beam would be held in one direction, but free to move as permitted by the clearance in the hole in the other.

I'm basically a mixed woodworker - hand and power tools - and find myself doing a lot of marking of pieces of sheet material to set up cuts on a panel saw. A panel gauge seems like it would be a highly useful tool in that situation too, although with some adaptations...

[Mark AJ Allen]

I made one for the same reasons.

1. Triangle arms - I'm assuming you mean the profile of the arms? While in theory I can imagine the tapered sides of the angled profile make the arm sit better in the body, It's probably not necessary if you have a good way to keep the arm from moving while scoring the panel. I made my panel gauge arm with angled sides. I did it for the challenge of whacking out an angled through-mortise, not because I thought it would be better.

2. I can't image any other way to make the bottom. How would a panel gauge work if it didn't have the rebate on the bottom guiding it?

[Steve Voigt]

The point of the triangular or trapezoidal beam is that when you force the beam down, with wedge or screw, it contacts both sides of the mortise simultaneously, so it can't rock or pivot.
With a rectangular beam, if the grain of the fence is oriented horizontally, the mortise will not shrink (in width), but the beam will. So after time, you may find that you need to over-tighten the beam to prevent it from moving. If you orient the grain vertically, as the Seaton gauges do, you won't have that particular problem.
FWIW, my experience is that the trapezoidal beam holds more securely. One small drawback is that it is so secure that it gets wedged in the bottom of the mortise and can be difficult to knock loose.

[Tom Blank]

Not to hijack the OP's post, but what species of wood works well for a panel gauge?

Thanks,

TB

[Matthew N. Masail]

Thanks guys, I did not think of needing the arm to contact 2 faces since it will be fit snugly, but it does make sense, especially in long term. but this makes an issue for regular marking gauges, which will see much, much more use, so I suppose the first thing to get right in the grain direction. if I understand correctly:
The body of the gauge has it's end grain horizontally, that is the top where the screw would have gone is long grain, in my case face grain because the piece is almost quartered.
The wedge will tighten from the side, so that a slightly loose fit of the arm horizontally doesn't matter, but I want to arm to stay snug over time vertically, shape aside for 1 sec, what would be the best grain orientation, having the end-grain of the arm running horizontally just like the body or the other way?
I understand the best way to guarantee a snug fit over time is the have a triangular face and the arm opposite the wedge, but I don't think I'd like to do that with every regular gauge I make, especially if it tends to 'stick'.

[Matthew N. Masail]

Not to hijack the OP's post, but what species of wood works well for a panel gauge?

Thanks,

TB

Tom, hijack forgiven. I've learned from making dozens of planes that any relatively stable and well wearing wood will do for such tools. you could use beech, maple, walnut, cherry or any other wood as long as it's stable and has some hardness to it. some of my best tools are made from some unknown pallet wood that is heavy and wears like glass.

[Jim Belair]

2. I can't image any other way to make the bottom. How would a panel gauge work if it didn't have the rebate on the bottom guiding it?

The face of the body would ride against the edge of the stock being marked, just like a regular marking gauge.

I'm planning to make a panel gauge soon so this thread is of interest to me.

[David Weaver]

I'd do triangular beam with a rabbet on the fence. I've got an old rosewood Stanley gauge, and its only fault is that it's square with a little slop and really has to be locked down tight.

[Matthew N. Masail]

Any advice on doing a triangular mortice? I played around with making square ones in beech today, seems like all is good until I try to pare down the across the grain then it's very stringy and dosen't pare cleanly (chisel is sharp). would you drill out and chop to a line from both side? chop from 1 side?

[David Weaver]

Cope it out, file it close and then finish pare lightly to level the surface if the file surface has a belly.

[Matthew N. Masail]

Sounds good.. I'll give it a shot

[Derek Cohen]

Hi Matthew

I would drill 3 corners, and then saw these out with a coping saw, finish with a chisel (use a guide block to ensure you are square). The rounded corners then require a beam with rounded edges. That is desirable anyway.

Regards from Perth

Derek

[ian maybury]

Probably not traditional, but my instinct would be to try to incorporate an accurate scale running in both directions/with a zero at both ends if i could - plus perhaps some sort of sliding stop. There's times when it's just a matter of repeating a distance, but times also when it's useful to be able to go to a specific dimension - and to have a step you cab butt something up against to get an accurate reference.

One thing in that context is that mass market tapes, rules and and scales are often quite a long way off being accurate. Sometimes it doesn't matter if the same one is used throughout a job (it repeats, even if its not exactly the stated dimension), but it can matter a lot where calculations are involved. Which is why a certified scale of some sort is possibly worth thinking about...

[Matthew N. Masail]

Hi Matthew

I would drill 3 corners, and then saw these out with a coping saw, finish with a chisel (use a guide block to ensure you are square). The rounded corners then require a beam with rounded edges. That is desirable anyway.

Regards from Perth

Derek

Thanks Derek! I give that a try also. I was going off the logan cabinet shop video, he just drills a hole in the center and chops to a line, but I'm having a hard time paring cross grain, maybe he's using a better wood for that. in any case I did 2, the first looked like crap the second was much better, I'll keep practicing with that and the other techniques.