Schooling on dados

[Christopher Charles]

Hi all,

I'm making very slow progress on a NBSS-style tool chest for under my bench. I just noticed that it was exactly a year ago that I finished the rough milling of the lumber. Once I have more to show, I'll post a build thread.

I purchased a LV Combo plane a bit over a year ago for the project, in part because I wanted to try dados by hand, and in part to upgrade my grooving plane. I fondly call it "The 17" because it has 17 adjustment knobs and it has proven to be a definite improvement over my vintage Record 043.

This weekend, I final had a chance to work on figuring out dados with the plane. I did learn several things and discovered a potential issue with my copy of the plane. My spotty results were a combination of learning a new technique, tuning a new (complex) tool and a set screw that isn't quite up to snuff(?).

Many, many thanks to Derek for his fine tutorial here:

http://www.inthewoodshop.com/ToolReviews/VeritasCombinationPlane-dados.html

Go read that and you'll know what to do. Read on for tips on what to avoid...

First, Derek is spot-on in noting that the nickers are critical. I tuned mine before starting, rounding the tips and getting them sharp. However, I also seem to have nickers that are soft and they rolled after the six short dados I cut (see below). Fortunately I have a friend with a metal shop and won't have to fly blind for my first adventure in tempering.

Second, Derek is also correct that getting everything dialed is tricky, especially the first time (or first several times).

Third, dados are hard! Most of my issues I chalk up to user error in set up and technique. I did hit the sweet spot a couple times and could feel the magic, but it was fleeting. Lesson: while I did do a several practice dados, more practice was in order when trying a new trick.

Lastly, at least some of my poor results stemmed from the blade moving, despite much checking of adjustments. Eventually I noticed that when the skates are perfectly aligned to the outside edge of the blade on both sides (so the nickers are also aligned), the lateral set screw does not quite engage the blade on my specimen. Only about 0.5 or 1 mm short, but enough that at least once it shifted and tore into the side wall of the dado, with nasty looking results. Anyone have thoughts on this? Would be straightforward to file down the casting so the screw could engage, but...

Fortunately, the nappy sidewalls will be inside the carcass, so I'm not too worked up about it, but am keen to get it all dialed in. I found the process quick once I got rolling and oh so much nicer than the table saw. I did manage 1 out 6 that wasn't totally embarrassing.

And again, thanks to Derek for his tutorial as I'm much further along than I would have been!

Thanks all,
Chris

Nicker afterwards

404946

Batten set up. Quick to set accurately with a combo square. Did one side then the other for each dado off the top as a reference side.
404947

Avert your eyes if you have a queasy stomach...here's the carnage:
404948

And finally a photo showing the gap between the lateral set screw and the blade:
404949

[Matt Evans]

Hi all,


Lastly, at least some of my poor results stemmed from the blade moving, despite much checking of adjustments. Eventually I noticed that when the skates are perfectly aligned to the outside edge of the blade on both sides (so the nickers are also aligned), the lateral set screw does not quite engage the blade on my specimen. Only about 0.5 or 1 mm short, but enough that at least once it shifted and tore into the side wall of the dado, with nasty looking results. Anyone have thoughts on this? Would be straightforward to file down the casting so the screw could engage, but...



I do not own that plane, so no hands on experience with it.

I would contact Lee Valley. They will likely have a solution (Or a longer screw)

I'd see if I could find a longer screw rather than filing down the casting. Even if you find one that is a few mm too long, you can file the screw without changing the casting at all.


I'd also ask about the nicker. If it is rolling over that badly with wood contact then something is awry. I've made plenty of cutters out of A36 mild steel that are still hardy and in the same shape, just dull, after a few goes on Hard Maple.

[Warren Mickley]

You might have done better figuring things out for yourself, Christopher. It will work better if there is some clearance between the nicker and the edge of the blade.

[Derek Cohen]

Hi Christopher

Sorry to hear that you are having a struggle.

As I mentioned in my article, the main set up goal is that ...

the nickers must be aligned exactly with the outer edges of the blade.

Warren suggests that they can be set further away. I am not going to argue much with this, but will say that the distance away should be no more than a smidgeon.

I had problems with the edge-holding of the nickers as well. For me, the solution was a 2 minute process of heating the tips red hot and quenching in oil (I assumed that they were O1). I left it at that. They have not chipped.

The other two items were, one, remove the screws that adjust the nickers and leave them flat against the outside of the skates. Two, score the boundary lines with a knife. Leave the nickers to aid in cutting cleanly as you plane deeper. I have described the reasons for these in my article.

Keep practicing. That is the only way.

Regards from Perth

Derek

[Christopher Charles]

Matt, thanks and I'm loath to mess with the casting.

Warren, to clarify, you recommend a bit of clearance with the blade extending a wee bit outside the skate and nicker (as in a rabbet plane)?

Derek, thanks for the guidance. I'm off for some peanut oil and a torch. I had the nickers and blade aligned to the skate as you recommend.

I remain curious if the gap between the blade and lateral screw is intentional on LV's part. I suspect not, as setting the skate in far enough to engage the screw leaves much too much blade exposed. Anyone with a combo plane and 1/2" blade have the same gap? Regardless, I'll check with LV and report back.

And I agree, practice is the best medicine and that missteps are part of the price of admission.

Best,
Chris

[Warren Mickley]

You don't want the blade interfering with the action of the nicker. The last thing you want is the blade to touch the sidewall of the dado as you are going; it will make a mess. You can have the distance between nickers as much as 1/16 wider than the blade ( 1/32 each side), and work quite nicely. But if you try to have the nicker and the blade line up exactly you are asking for trouble.

[Stewie Simpson]

Chris; take on board the advise Warren has supplied within the above post, and also refer back to the instructions that were supplied with that plane. (see below)

Setting the Scoring Spurs.

The scoring spurs enable cross-grain work by severing the fibers ahead of the blade, preventing tear-out. There are two screws that adjust the scoring spur, as shown in Figure 7. The spur retention screw locks the spur into position and the spur adjustment screw sets how far the spur protrudes from the face of the skates.

[Derek Cohen]

You don't want the blade interfering with the action of the nicker. The last thing you want is the blade to touch the sidewall of the dado as you are going; it will make a mess. You can have the distance between nickers as much as 1/16 wider than the blade ( 1/32 each side), and work quite nicely. But if you try to have the nicker and the blade line up exactly you are asking for trouble.

Warren, I am not sure if we are saying the same thing or not.

I say that the edge of the blade must get as close to the line cut by the nicker as possible. I think that you are saying that there can be as much as 1/16" each side of the blade, but probably closer to 1/32" each side. My problem with this is that the dado will end up over-sized (and will require that you size the piece for the dado later for a fit).

A dedicated dado plane, such as the HNT Gordon, sizes the nicker for the blade width. A 1/2" wide blade will cut a 1/2" wide groove. "Used to make a 1/2" dado (grove) across the grain or with the grain. The precision made nicker ensures a very neat and accurate dado as the wood fibres are cleanly severed when planing across the grain."

The same occurs for the Veritas Combo plane blade used for a dado. It is exactly 1/2" wide.

HNT Gordon and Veritas 1/2" blades (=12.7mm) ...

https://i.postimg.cc/CxnhSn8Z/IMG-2129.jpg

https://i.postimg.cc/q7fkRBc1/IMG-2135.jpg

If there was no nicker to cut ahead of the blade, the wood would spelch. Placing the nicker in line with the edge of the blade is tricky, but is the ideal. Giving it a smidgeon leeway - not enough to alter the dimension - would be a safe choice. But we are talking (or at least I am) less than 1/64". That is far less than you are advocating.

So what am I missing here? Always happy to learn ... Is this a 18th vs 21st Century issue?

Regards from Perth

Derek

[Warren Mickley]

No, we are not saying the same thing. I am saying there needs to be clearance; you are saying that the nicker is supposed to be "in line with the edge of the blade."

[Derek Cohen]

Warren, I agree that there needs to be clearance ... just not as much as you suggest. I am not doubting what you say - just trying to understand the reasoning, which you have not explained. My tolerances are smaller than yours. The three dado planes in the demonstration I did were set up as I described above. Each produced clean shoulders. No spelching evident. Evidently, this works.

Here are two questions: (1) if you have the cutting edge of the nicker 1/16" each side of the blade, what makes the dado a clean cut? (2) Is there a smaller size blade/nicker combo to create a 1/2" (etc) sized dado, or is this irrelevant?

Regards from Perth

Derek

Regards from Perth

Derek

[Warren Mickley]

It sounds like you are having trouble reading what I wrote.

I said "You can have the distance between nickers as much as 1/16 wider than the blade ( 1/32 each side), and work quite nicely." I did not say that the clearance needed to be 1/32. I did not "suggest" an amount.

I think you would have trouble planing a dado that is 12.70 mm with an iron that is 12.70 or 12.71 mm wide. The nearest iron that came with my 45 plane is .476 inches. One could make a .500 dado with it but just a .476 groove. I bought the plane in 1983; this is the first I measured it.

[Derek Cohen]

Gad, Warren, having a conversation with you to obtain any detail is like pulling teeth.

For the sake of the forum, I shall plane a few dados on the weekend and measure their width. Am I expecting exactly 1/2" on a 1/2" blade? No. However, it may not be much over this. Certainly not as much as a 1/16" each side.

Regards from Perth

Derek

[Nicholas Lawrence]

Derek, you keep referencing 1/16 on “each side.” Warren did not say that. He said up to half that on either side (post No. 6). It is in the post you quoted (post No. 7). He makes that very clear in Post No. 11, but in post No. 12 you are still talking about “a 1/16” each side.”

The fact that you keep misquoting/misunderstanding him might be part of the difficulty in communication.

[Derek Cohen]

Nicholas, you are correct. I misread that. Warren did write 1/16 wider than the blade, and not 1/16 each side. My apology.

Regards from Perth

Derek

[Christopher Charles]

Warren and Derek,

Miscommunication aside, thanks for the clarifications. These details are exactly the kind of feedback I was looking for and will hopefully be of use to others as well.

Best,
Chris

[Stewie Simpson]

Nicholas, you are correct. I misread that. Warren did write 1/16 wider than the blade, and not 1/16 each side. My apology.

Regards from Perth

Derek

Derek; attached is a thread that Warren replied too back to 2015. https://sawmillcreek.org/showthread.php?227090-Question-on-quot-nicker-quot-iron-for-wooden-dado-plane

Stewie;

Warren Mickley (https://sawmillcreek.org/member.php?117006-Warren-Mickley)


The nickers have to be wider than the cutting iron. If they are very close to the same width, the alignment has to be perfect to avoid trouble. The nickers also have to be wider than the body of the plane. If they are too close in width there is danger of the plane stock rubbing the walls of the dado, which gives problems also. You should not narrow the nicker blade unless you would consider narrowing the stock of the plane also. If there is 1/32 or less between the nicker and the edge of the blade on each side, you should have no trouble.

5/16 is a common size for a dado plane. In historic times, rather than have a set of different size planes, they often got a 5/16 and made two cuts on the board, one for each edge of the dado. So for 7/8 they would make two 5/16 cuts and chisel out the 1/4 in the middle. This enables one to make a dado 7/16 or 27/32 or whatever with one tool. If you want a 1/4 dado, I would get another plane.

[James Pallas]

Hi all,

I'm making very slow progress on a NBSS-style tool chest for under my bench. I just noticed that it was exactly a year ago that I finished the rough milling of the lumber. Once I have more to show, I'll post a build thread.

I purchased a LV Combo plane a bit over a year ago for the project, in part because I wanted to try dados by hand, and in part to upgrade my grooving plane. I fondly call it "The 17" because it has 17 adjustment knobs and it has proven to be a definite improvement over my vintage Record 043.

This weekend, I final had a chance to work on figuring out dados with the plane. I did learn several things and discovered a potential issue with my copy of the plane. My spotty results were a combination of learning a new technique, tuning a new (complex) tool and a set screw that isn't quite up to snuff(?).

Many, many thanks to Derek for his fine tutorial here:

http://www.inthewoodshop.com/ToolReviews/VeritasCombinationPlane-dados.html

Go read that and you'll know what to do. Read on for tips on what to avoid...

First, Derek is spot-on in noting that the nickers are critical. I tuned mine before starting, rounding the tips and getting them sharp. However, I also seem to have nickers that are soft and they rolled after the six short dados I cut (see below). Fortunately I have a friend with a metal shop and won't have to fly blind for my first adventure in tempering.

Second, Derek is also correct that getting everything dialed is tricky, especially the first time (or first several times).

Third, dados are hard! Most of my issues I chalk up to user error in set up and technique. I did hit the sweet spot a couple times and could feel the magic, but it was fleeting. Lesson: while I did do a several practice dados, more practice was in order when trying a new trick.

Lastly, at least some of my poor results stemmed from the blade moving, despite much checking of adjustments. Eventually I noticed that when the skates are perfectly aligned to the outside edge of the blade on both sides (so the nickers are also aligned), the lateral set screw does not quite engage the blade on my specimen. Only about 0.5 or 1 mm short, but enough that at least once it shifted and tore into the side wall of the dado, with nasty looking results. Anyone have thoughts on this? Would be straightforward to file down the casting so the screw could engage, but...

Fortunately, the nappy sidewalls will be inside the carcass, so I'm not too worked up about it, but am keen to get it all dialed in. I found the process quick once I got rolling and oh so much nicer than the table saw. I did manage 1 out 6 that wasn't totally embarrassing.

And again, thanks to Derek for his tutorial as I'm much further along than I would have been!

Thanks all,
Chris

Nicker afterwards

404946

Batten set up. Quick to set accurately with a combo square. Did one side then the other for each dado off the top as a reference side.
404947

Avert your eyes if you have a queasy stomach...here's the carnage:
404948

And finally a photo showing the gap between the lateral set screw and the blade:
404949

Be careful before taking a file to anything. The knob your trying to adjust is for wide blades to help set the skate to the blade. The smaller blade adjuster is on the other side.
Jim

[steven c newman]

After reading all of this....makes me glad all I have to work with is a Stanley 45, and the No. 39 3/8" Dado plane....

[James Pallas]

After reading all of this....makes me glad all I have to work with is a Stanley 45, and the No. 39 3/8" Dado plane....

Well by golly Steven. If your 45 is in full dress there are only two les screws to adjust than the 17 on the Veritas. That is if you have one with the fine fence adjustment. The two more screws on the Veritas includes the one mentioned above and the small blade adjuster
Jim

[Steven Mikes]

All this talk makes cutting dados with the combination plane look like a very fussy affair. Does it produce noticably better results in the end than sawing the side walls against a fence and chiselling/routing the waste out?

[Derek Cohen]

Derek; attached is a thread that Warren replied too back to 2015. https://sawmillcreek.org/showthread.php?227090-Question-on-quot-nicker-quot-iron-for-wooden-dado-plane

Stewie;

Warren Mickley (https://sawmillcreek.org/member.php?117006-Warren-Mickley)

The nickers have to be wider than the cutting iron. If they are very close to the same width, the alignment has to be perfect to avoid trouble. The nickers also have to be wider than the body of the plane. If they are too close in width there is danger of the plane stock rubbing the walls of the dado, which gives problems also. You should not narrow the nicker blade unless you would consider narrowing the stock of the plane also. If there is 1/32 or less between the nicker and the edge of the blade on each side, you should have no trouble.

5/16 is a common size for a dado plane. In historic times, rather than have a set of different size planes, they often got a 5/16 and made two cuts on the board, one for each edge of the dado. So for 7/8 they would make two 5/16 cuts and chisel out the 1/4 in the middle. This enables one to make a dado 7/16 or 27/32 or whatever with one tool. If you want a 1/4 dado, I would get another plane.



Well Stewie, you should recall the old adage of "let sleeping dogs lie". You cannot resist stirring. If you are going to cite that thread, then include a bit more than just Warren's comments.

Fred Skelly had been asking about a 1/4" dado plane he was setting up. He wanted it to cut a 1/4" dado. I offered advice that, in a nutshell, was that he needed to adjust/fine tune the blade and knickers together so that the knickers still prevented any spelching. If you are up to it, it can be painstaking work setting this up, but it does work.

After some trial-and-error work, Fred reported back with success. "As others said - the cutter, the sides of sole and those doggone nickers MUST all be coplanar. Correcting this was another noticeable improvement". What I should caution her is that the nickers need to extend wider than the body of the plane, otherwise the plane will bind along the straight edge. However one side can be coplanar.

I spent a little time looking through my references last night. There really is not much available on setting up a dado plane on the Internet. In my own library there is a chapter by Michael Dunbar in his book, "Restoring, Tuning & Using Classic Woodworking Tools". He does not offer any useful advice on the width/placement of the nicker.

The other reference I had was a video by Bill Anderson (https://store.woodandshop.com/product/dvd-choosing-refurbishing-using-joinery-handplanes-with-bill-anderson/), who works with Roy Underhill at his Woodwright School. His recommendation was to have the nicker and blade at the same width.

I believe that one will find few opinions these days because few people actually use these planes. I use them, but not that often. I tend to make more stopped dados, and a knife, chisel and router plane work well here. As noted above, my recommendation has been to create a closer relationship between the nicker and blade than Warren does. I have no doubt his method works. Mine does as well.

For reference, I gave the HNT Gordon dado plane a few quick swipes across a board to measure the width of the dado created. I followed the set up procedure in my article. The result was a very clean dado without any spelching (I am happy to take a photo, but this is written in a lunch break, and I did not have time). Recall that the width of the blade is 12.7mm (exactly 1/2"). The dado measured 12.84mm. In other words, the nicker projects 0.07mm each side of the blade. Note that this is a standard set up for a modern dado plane (one reason why I asked Warren if we were setting 18th century or 21st century expectations).

The reason I do not use the nicker screws on the Veritas Combo Plane is that I set the width with the skates instead. The nicker can remain flat against the sides of the body. The skates are opened (along with the body) to ensure that the blade is aligned a smidgeon inside the outer edge of the nicker. This is easier to do than is sounds. The result is, as I demonstrated in the article, very clean dados. (Keep in mind, Stewie, that I completed three dados alongside one another with three different planes. There was no room for error or fudging the result. any error would have been easily noticed).

The best advice I can give at this point is that you go and practice yourself and decide what works best for you. That is NOT a choice between Warren or myself. I do get what Warren is suggesting. I am simply stating that it is possible to dial it in if you want to go to the trouble and are using a sympathetic dado plane.

Regards from Perth

Derek

[Warren Mickley]

All this talk makes cutting dados with the combination plane look like a very fussy affair. Does it produce noticably better results in the end than sawing the side walls against a fence and chiselling/routing the waste out?

The results for either method depend on the skill of the worker. For someone who can do either method, the dado plane is considerable faster. I think it also would have been easier to explain the need for clearance to an 18th century worker than someone today.

[steven c newman]

Mine does in indeed have the fence fine adjuster....used it a couple days ago.

However....note on the 45 on how it places the spurs/knickers...they are ahead of the cutters, outside edges of both are coplannar . And, I usually drag the plane backwards a few times, for the spurs to do their job first, then push to make the first cut...

The 39s have spurs about the same as this new fangled plane....biggest trouble I have with those is they like to move a bit, inspite of 2 bolts holding each...

Warren....post a photo of the spurs on a wood bodied dado plane...and how those line up with the iron....
405136405137
Second picture shows the spurs doing their job, before a cut was started with the #18 cutter..
405138
set up....to avoid any "blowouts " where the plane starts and stops at..
405139
Backsaw cuts just at the start, and at the exit points...I let the spurs handle the middle area..
405140
To aid in getting a filled drawer into the case, I cut a little "ramp" at the back corners...
405141
Spurs..

[Derek Cohen]

Steven, to clarify what I wrote about setting up the nickers on the Veritas Combo, essentially I do it the same way as on the #45.

Regards from Perth

Derek

[Philippe Grant]

And finally a photo showing the gap between the lateral set screw and the blade:
404949

Christopher, this gap should not be there. The screw needs to laterally plate support the blade otherwise it will tend to wobble side to side as you plane (no matter how solid your fencing and plane movement).

Do share a picture showing you full sliding section configuration in relation to the blade. I suspect your sliding section is not properly positioned. It needs to be pushed closer to the body so that your blade is symmetrically supported from below by 1) the support plate in the main body (this positioning is fixed) and 2) the support plate in the sliding section (this positioning is done by you by loosening the two sliding section locking knob screws and sliding the sliding section closer to the blade).

Good luck!

Another suggestion I would add is to make sure your cutting spur and your tool is overall very clean of splinters, shavings and sawdust. A lot of things can go wrong so go slow, take light passes, and remove shavings and splinters every two or three passes. Also make sure everything is pristine before inserting your blade into the plane. Splinters or sawdust will cause misalignment.

Phil

[Brent Kane]

No, I don't set up all my planes with micrometers. I did the following exercise strictly to find my own answer to the question(s) I had about this thread. And, just because I at least try to be helpful on occasion, I hauled out a camera and recorded my efforts.

Materials: Veritas combination plane, 1/2" cutter, scrap piece of dried (brittle) fir, digital depth gauge & digital caliper.

1--With the cutter fully inserted and engaged I measured how far it extends beyond the skate of the main body, 0.010" (That's a function of the design of the plane - it's non-adjustable)
405164


2--I adjusted the sliding section to get the same amount of cutter standing proud of the skate, also 0.010"
405165


3--The width of the cutter itself measures out to 0.5000" and the width at the outside of the skates is 0.4980".
405166 405167


4--I get best results with thin cuts, so I set the blade to a depth 0.0025" beyond the runners of the skates.
405168


5--When I first tried this plane I started out with deeper sets of the nickers and had problems with drag, bent tips, and waste wood wedged between those nickers and the skates. All we need to do here is slice ever-so-slightly deeper into the wood than the sharp edge of the cutter. I've found that the somewhere around 0.015" does just fine, but this is not a highly critical measurement! In other words, the business portion of the nicker only needs to extend about 1/64" beyond the cutter depth. Yes, the tips of the nickers look pretty rough - but that doesn't seem to have much of any effect on the fir I used. Whether they need to be more finely dressed for dadoing other species is beyond the intent of this post. As for the width - the nickers are in line with the outside edge of the skates. I removed and tossed those little set screws that allow one to flare out the nickers.
405169 405170

I did this in the backroom of my studio - not at my workbench. You can see the quick and crude setup I used, as well as the results of the cuts. I leave it to your imagination what you can do with a plane such as this - set up properly - with better wood, clamps, etc.
405161

I hope this helps!
Brent

[Christopher Charles]

Hi all,

Thanks for the lively discussion. I'm finding it useful.

I heard back from LV customer service. Here is their recommendation on the nicker (=spurs) issue:

The Scoring Blades (05P5902) are quite delicate and should only protrude slightly below the skate (to a maximum of 1/32”) when cutting across the grain. It is possible that they rounded because they were protruding too far. They should always be sharpened to a point.

As is typical, they have shipped replacements, which was not necessary (nor did I request) but I do appreciate.

Here is the guidance with respect to aligning the blade, skates and nickers:

In order for the lateral adjustment screw to make contact with the blade, we recommend not aligning the blade perfectly with the edge of the skate. Depending on which blade you are using, make sure that the skates are supporting the blade. This means that the blade will sit a hair out from the edge of the skates. As see in Figure 7 in the instructions (http://www.leevalley.com/en/wood/page.aspx?p=76198), the Spur Adjustment Screw can be used to set how far the spur protrudes from the face of the skates. What this means is that you can line the spurs up with the edge of the blade. After tweaking your adjustments, this should allow the lateral adjustment screw to make contact with the blade as well as keep the blade from wandering.

This guidance is in line with Warren's and means the set screws would be needed to push the nickers outboard.

Brent, thanks for the measurements and examples. Those measurements match what I got when I took calipers to my plane this morning. I suspect part of my issues may have been I had the nickers extended too far. Unfortunately, I won't have time to practice for another day or two.

Derek, could I ask if your 'blade guide knob' engages the main blade on your plane when you have the skates aligned to the edge of the blade (as I had in my set-up above)?

[Derek Cohen]

Christopher, the blade guide knob is tight against the blade.

This situation reminds me of the efforts to quantify the distance of a chipbreaker from the edge of a blade. You do just enough to get the desired effect. An exact number, per se, can confuse the matter. As we find, the number for the nicker is very small.

Regards from Perth

Derek

[Christopher Charles]

Hi Derek,

Thanks and I agree this discussion has gone down a rabbit hole! Nonetheless, your reply gets me back to my original question.... With my plane, the blade guide knob will not reach the blade when I have the skate even with the edge of the blade (as per your tutorial).

Thus,
1) the blade remains unsupported if aligned with the skate on both sides (following your method with my particular plane) or
2) the blade is outside the skates (as recommended by Warren and LV) and the nickers must be set outside the skate using the set screws or
3) the nickers are inside the blade if the nickers are used without the set screws and are set in-line to the outside of the skate (undesirable all around).

While it is picking nits a bit, I was unclear if the gap between the blade and blade guide knob was an intentional part of the design (apparently 'yes') or a short-coming of my particular plane. Mine appears to be in spec.

I truly do appreciate the guidance here and am positive the best approach is practice. Nonetheless, it is helpful to know the best staring point(s) in terms of set up. At least I know two (three?) of the roads to Rome :)

Steve, thanks for posting photos, I like your method of saw kerfs to limit spelching.

Best,
Chris

[Stewie Simpson]

The following measurements were taken from a dedicated 3/8" (9.52mm) wooden dado plane.

9.01MM (sole width.)

9.32MM (cutting iron width.)

9.60MM (spur width)

https://i1009.photobucket.com/albums/af219/swagman001/dado%20plane/DSC_0202_zpswyfh2fya.jpg (https://s1009.photobucket.com/user/swagman001/media/dado%20plane/DSC_0202_zpswyfh2fya.jpg.html)

[John Schtrumpf]

The following measurements were taken from a dedicated 3/8" (9.52mm) wooden dado plane.

9.01MM (sole width.)

9.32MM (cutting iron width.)

9.60MM (spur width)



In case anyone is wondering, 0.3MM is approximately 1/85 of an inch.

[Warren Mickley]

I made two dados this morning using a combination plane. Both dados had the same iron, but had different spacing of nickers and skates. One dado was .504 wide, the other was .569 wide. Here are the measurements:
.
Blade .476
Skates .472
Nickers .504

Blade .476
Skates .537
Nickers .569

If the nickers are not wider than the skates, the skates will rub the sidewalls and become tight. If the nickers are not wider than the iron, the edge of the iron will rub the side walls als a problem.

Those who suggest that the iron ought to line up with the nickers or that the nickers ought to line up with the skates, probably don't have much experience.

[Philippe Grant]

I believe the biggest issue the OP faced relates to the sliding section position, which causes the skate to bottom out preventing the cutter from reaching the "meat" and the shifting the blade guide knob screw away from the blade, leaving it unstable laterally.

Wide blades (over 3/16") have to be supported by both skates. If the sliding section is too far from the plane body, its skate will not support the blade and the blade guide knob screw will not support the blade laterally.

Hopefully this picture clarifies beyond what prose can achieve. I'm not addressing the spur positioning, which is secondary to the skate and sliding section positioning (it's still important, but if you don't place the sliding section in the right place, the spurs don't even come into play).

Click to enlarge.

405235

[Stewie Simpson]

I believe the biggest issue the OP faced relates to the sliding section position, which causes the skate to bottom out preventing the cutter from reaching the "meat" and the shifting the blade guide knob screw away from the blade, leaving it unstable laterally.

Wide blades (over 3/16") have to be supported by both skates. If the sliding section is too far from the plane body, its skate will not support the blade and the blade guide knob screw will not support the blade laterally.

Hopefully this picture clarifies beyond what prose can achieve. I'm not addressing the spur positioning, which is secondary to the skate and sliding section positioning(it's still important, but if you don't place the sliding section in the right place, the spurs don't even come into play).



Phillippe; then explain to me why you chose to designate the position of the sliding skate (shown in example 2) as being Acceptable.

https://sawmillcreek.org/attachment.php?attachmentid=405235&d=1552051343

[Jim Koepke]

Phillippe; then explain to me why you chose to designate the position of the sliding skate (shown in example 2) as being Acceptable.



Not Philippe, but that looks like a set up for with grain plowing and not for cutting a dado.

jtk

[Philippe Grant]

Phillippe; then explain to me why you chose to designate the position of the sliding skate (shown in example 2) as being Acceptable.

https://sawmillcreek.org/attachment.php?attachmentid=405235&d=1552051343

I made the diagram to illustrate the correct skate alignment and then contrast the effect of shifting the sliding section closer or further from the plane body.
So why is it "acceptable"? Well, it's not the best sliding section alignment, but you should be able to do a nice cut if you make the right adjustments to your spurs (i.e. if the gap marked by the left pointing arrow is not too wide). Also your blade is supported laterally, and the skate doesn't bottom out into the wood you actually want to cut.

what do you think?

[Jim Koepke]

what do you think?

My thought is that is okay for plowing grooves with the grain and even needed when cutting a rabbet/rebate narrower than the blade being used. Doing this when cutting a dado is likely to leave one edge ragged.

jtk

[Stewie Simpson]

A question for users of the Veritas Combination Plane. Is there an adjustment that allows the user to set the cutting edge outside the line of the fixed skate for rebate work.

[Derek Cohen]

A question for users of the Veritas Combination Plane. Is there an adjustment that allows the user to set the cutting edge outside the line of the fixed skate for rebate work.

Yes - each nicker has a set screw that opens the nicker out from the skate. Further, only one skate is "fixed". The other slides on the fence rods.

However, one does not use a nicker for rebates. Instead, the plane blade is extended a smidgeon outside the wall of the plane body. This allows it to cut into the corner of the rebate. On the Veritas plough planes, both the Small and the Combo, one does this by angling the blade (very slightly).

Regards from Perth

Derek

[Stewie Simpson]

The reason I asked, is its not considered common practice to engage the nicker when working long grain rebates.

[Derek Cohen]

I took a few photos yesterday to show a few set up details, along with their results, in keeping with the original questions at the start of this thread. Setting up the Veritas Combo Plane for a dado takes me about 1 minute, perhaps less. I will show this.

The other factor is that of positioning the nickers. I consider this to be at the heart of setting up a dado plane, be it of the combination plane style, where there are individual nickers, and placed at either side of the plane body. A combination plane extends the width of the body using two skates. There is a second type of nicker system, which is a single nicker divided into two cutting sides. This is the version used by many vintage woodies and, more recently, HNT Gordon. From my review (http://www.inthewoodshop.com/ToolReviews/HNTGordonDadoPlane.html) ...


http://www.inthewoodshop.com/ToolReviews/HNTGordonDadoPlane_html_m373cca72.jpg


Close up of the nicker … http://www.inthewoodshop.com/ToolReviews/HNTGordonDadoPlane_html_m503e838b.jpg




With the Veritas, there is a nicker on the outside of each skate ...

http://www.inthewoodshop.com/ToolReviews/VeritasCombinationPlane-dados_html_m178e690e.jpg


This is adjustable, using a set screw, which pushes the nicker/blade away from the body.

My preference (which runs against the recommendation of Veritas) is to remove the set screws (because they fall out and get lost otherwise) and set the nicker for minimal (more on this in a moment) projection from the skates. As mentioned before, I rounded the tips of the nickers (they came pointed). There were two reasons for this. Firstly, the original tips of my pre-production plane were fragile and broke off. I hardened them. Secondly, the rounded edge seems to me to slice more easily than a pointy tip, and the plane cane be drawn back of the work piece as well as pushed through it. In other words, it is less directional.

The depth of cut is not really a number. Numbers are starting points. Say 1/16". We really want the nicker to be set a smidgeon more than the depth of cut, as it needs to slice the cross grain ahead of the blade. Too deep and the nickers will just make the plane harder to push.

http://www.inthewoodshop.com/ToolReviews/VeritasCombinationPlane-dados_html_m5093d5ed.jpg

Now warren made an important point at the start of this thread when he wrote that, because the nickers must lie outside the side of the blade, they cannot leave a dado the width of the blade. I agree with this, and it becomes the main topic here.

If using power tool methods, it is possible to prepare boards (to fit) and the dados in an interchangeable order, since they can be made to the same width. For example, a 1/2" power router bit creates a 1/2" dado, and one can thickness 1/2" thick boards quite separately. On the other hand, if using hand tools, it is relevant to create the dado first and the board thickness second - based on the width of the dado.

The question is "how close to 1/2" can we create a dado?". In other words, assuming a 1/2" wide dado blade (straight or skewed), what is the minimal amount of dado projection we can get away with before the side walls begin to spelch?

So I set up a simple examination (this took far less time than the write up!). Veritas and HNT Gordon planes and a small piece of Radiata Pine scrap ...

https://i.postimg.cc/zvKQxv8y/1a.jpg

The Veritas blade is exactly 1/2" (as one might expect) ..

https://i.postimg.cc/qB3WJbyp/2a.jpg

Now I have stated before that I set up the nickers flush with the sides of the skate (and then adjust the skates outside the blade). This is not quite accurate. Indeed I set them up this way ...

https://i.postimg.cc/bJKM0kcX/3a.jpg

https://i.postimg.cc/bNfWsx9k/4a.jpg

Why I say that this is not quite accurate is that my nickers have been used with the set screw, and this has deformed them very, very slightly. So now, when I try and set them flat against the side of the skate, they do not sit flush, and project very, very slightly. I cannot measure the amount of projection, only feel it with a finger tip. This has a bearing on the set up and the results. More in a short while.

Here is a tool needed for planing dados - a straight edge. Traditionally, one would simply nail a wooden fence to the work piece. The nail holes would be either filled or ignored. The Veritas requires the fence to be a 1/4" high. So I have a straight edge with non-slip and a square reference at one edge ...

https://i.postimg.cc/XYVPgnhv/6a.jpg

If the work piece is held firmly, it becomes a simple matter to clamp down the straight edge ...

https://i.postimg.cc/d17pTnfm/7a.jpg

I then pull the plane back against the fence, but very lightly. All I want is a positioning of the outside nicker ...

https://i.postimg.cc/YCbsnJKz/8a.jpg

Nickers are not always the cleanest cutters - not sharp enough - for leaving a pristine side wall. And so I prefer to knife them in ...

https://i.postimg.cc/hGv3HpKW/9a.jpg

Now go ahead and plane the dado, beginning at the far end. The depth stop will keep it level (note that I have not relieved the end of the dado here, as I generally would to prevent spelching. This example is about the nicker, not the finish at the end of the dado. I am not even using the depth stop).

https://i.postimg.cc/DzNYFLzW/10a.jpg

https://i.postimg.cc/63GbQq7M/11a.jpg

[Derek Cohen]

How wide is this?

https://i.postimg.cc/6qJj4Knt/12a.jpg

https://i.postimg.cc/T1VkrsJm/13a.jpg

That is 0.55mm/0.02" wider than the blade. mmmm .... not that great a result as far as I am concerned. I am sure it is possible to do better.

The HNT Gordon dado plane is my reference here. It is set up in a similar way, but stock standard. The blade was previously measured also as exactly 1/2" (12.71mm on this occasion). It has a skewed blade, but that only affect the cleanness of cut (the skewed blade leaves a cleaner finish). The nickers protrude from the body of the plane, but again I can only feel this with fingertips as it is not obvious.

A clean slate ...

https://i.postimg.cc/R02G2mPK/14a.jpg

Planed ...

https://i.postimg.cc/mg2dH8zz/15a.jpg

Measured ...

https://i.postimg.cc/jdT3ssRh/16a.jpg

https://i.postimg.cc/YCndfYYX/17a.jpg

That is a better result than the Veritas. So, let's try the Veritas again, with the skates set up a tad closer together ...


https://i.postimg.cc/gc8BFwbJ/20a.jpg

That is a tighter fit for a 1/2" thick board, and visually it looks good in that there is no spelching. As I look at the photo now, I can see compression on the right sidewall. It is not present on the left sidewall. Is that from knifing the line, or from the nicker?

In conclusion, as one moves the nicker closer to the blade, the leeway for error is lowered. One question is "Is it worth it?". I guess the answer is that one needs to recognise that hand tool work is best done in a specific order. Power tool thinking needs to be set aside here. It is evident that one can get pretty damn close to the width of the blade - the amounts exceeded here are unlikely to be registered visually - and that the amount of leeway can be pretty damn small.


Regards from Perth

Derek

[Philippe Grant]

A question for users of the Veritas Combination Plane. Is there an adjustment that allows the user to set the cutting edge outside the line of the fixed skate for rebate work.
Nope, that is not possible.

[Philippe Grant]

My thought is that is okay for plowing grooves with the grain and even needed when cutting a rabbet/rebate narrower than the blade being used. Doing this when cutting a dado is likely to leave one edge ragged.

jtk

I'm with you Jim. ;)

[Warren Mickley]

Nope, that is not possible.

Philippe, you may have misunderstood what Stewie meant. For grooves or rabbets the blade cuts the sidewall of the rabbet and needs to protrude a small amount for clearance, so the skate does not rub the side wall. I don't think he was thinking it would be outside the line by very much.