Log in

View Full Version : Making my first panel gauge and have a few simple questions



Matthew N. Masail
09-06-2014, 4:39 PM
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
09-06-2014, 6:38 PM
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
09-06-2014, 7:59 PM
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
09-06-2014, 11:07 PM
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
09-07-2014, 12:19 AM
Not to hijack the OP's post, but what species of wood works well for a panel gauge?

Thanks,

TB

Matthew N. Masail
09-07-2014, 2:44 AM
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
09-07-2014, 2:48 AM
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
09-07-2014, 7:47 AM
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
09-07-2014, 9:42 AM
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
09-07-2014, 9:54 AM
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
09-07-2014, 10:24 AM
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
09-07-2014, 11:31 AM
Sounds good.. I'll give it a shot

Derek Cohen
09-07-2014, 11:57 AM
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
09-07-2014, 12:47 PM
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
09-07-2014, 1:10 PM
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.

Alan Schwabacher
09-07-2014, 2:12 PM
The ones with the wedge running crosswise to the beam are nicer to use than those with the wedge running along the beam, in my opinion. You can set the distance, and tighten by squeezing in the wedge without risk of changing the setting.

Lots of beam cross sections work fine, if you round or chamfer any potentially sharp corners. If you use a square, just wedge so as to push diagonally into a corner. You can even use a round beam with a single flat for the wedge to engage, and the cutter will remain pointed in one direction. Then you can drill the mortise.

Winton Applegate
09-07-2014, 5:27 PM
I am open to critique / criticism. It is dry here in the Wild, Wild West so perhaps this wouldn’t fly in England or the more humid or changeable parts of the world.

On the end of the maple gauge I used a blue lumber crayon to show the grain curvature and direction. I was enjoying the saw tooth texture on the end contrast with the super smooth and subtle grained faces so I didn't plane the ends.

The short marking gauge in the first photo is probably the first one I ever made or maybe the second. I made it when I was practicing and learning mortising by making my cutting table out of 2x4s. (The first thing I learned was don’t make stuff out of 2x4s) It is a dedicated mortise gauge to go with my big honkin’ mortise chisel so like the chisel is not going to get a lot of use right ? So the most basic and close to hand materials were just fine for this gauge. Functionally it turned out better than bare necessity.

I am not recommending you make your panel gauge as I made this first one but I was fooling around with it today and noticed it is “unique” in two respects.


First ha, ha, the beam is made from a strip of particle board (the fence is a cutoff of 2x4). How’s that for going all out on materials?
Secondly the beam still fits perfectly in the fence meaning when the “set screw” is loose it is snugish but moves with a slightly more than light tap on the bench or with a hammer. The set screw is a machinist T-bolt that is normally used by machinists in T-slots in the machine tables for hold down duty. Here it threads into a brass threaded insert designed to put an anchor of machine threads into a wood base.


The marking pins near the end of the beam are the exact width of the mortising chisel.
Soon after I made this . . .
The second gauge I put much more thought and materials and effort into.
Patterned after the Japanese style and I think I made it after being inspired by a FWW article.
Flat beveled, steel, round, marking pin in one end and in the opposit end a hole that fits a regular pencil tightly. Ignore the direction of the pin/pencil hole and the wedge and the beam rotation. I know the slightly skewed metal pin should pull on the wedge to make it tighter in the fence in use. I was trying to show all the features while using as few photos as possible.

Made from roc maple. I think this is a good material for a long gauge like this. Well not long but can always make longer beams for it.

I didn’t put the rabbit along the edge of the fence as discussed here but I could see how that could be useful to clear surface features in the work being marked; might require a different configuration of the marking tool. As with the longer beam I figured I could always add that.

The rectangular tool adjusting hammer also shown works particularly well with this gauge. Oops I guess I need to include another photo after all.

Mark AJ Allen
09-07-2014, 8:13 PM
OK I understand now. I would think the rebate is easier to control; both surfaces of the rebate will ride on the panel. If there is no rebate, it the gauge needs more control to prevent the beam from touching the panel. Not a huge deal I guess.