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View Full Version : Those bench dogs yet again....



ian maybury
10-31-2011, 10:23 PM
To ask a very specific question. The traditional square dog and hole seems to work really well with a wagon vise to hold work for hand planing. Can those who have used both say if 3/4in round dogs work as well or at least close to as well as the square type in this role? Do they and the holes last well?

As in the recent discussion on vises I've started laying out a Roubo style bench which will probably have a wagon vise on the RH end, and a twin screw on the LH end of the face. I have some hammer in hold downs, and would like to be able to use these with 3/4 dia Veritas bench dogs or similar DIY with a grid of 3/4 in holes to clamp laminated frames, circles and the like.

This grid of round holes doesn't seem to rest easily with the traditional row of square holes for planing/the wagon vise down the near side.

Trouble is though it'd be a pity to compromise holding performance in the traditional hand planing role as above by using round dog holes in the row for the wagon vise - if in fact this is a genuine issue.

The original thought was to use a face vice on the end and round dog holes in the moving jaws to cover both functions - but racking and vertical movement in these versus the apparently excellent performance of a good wagon vise led to the decision to go with the latter.

Perhaps there's another solution that delivers the best of both worlds. Or is it necessary to choose between a hand tool oriented single square hole row and wagon vise, and a more general purpose grid of round holes?

Thanks

ian

Mike Zilis
10-31-2011, 11:52 PM
My opinion is that with 3/4" round dog holes and a Veritas quick release Sliding tail vise you get all the good with none of the bad.

Alan Schaffter
11-01-2011, 12:20 AM
Frankly the round dogs have as much face surface as most square dogs. Off-center positioning of the work will have the same effect on both. Two BIG benefits of round dog holes - (1) they are MUCH quicker and easier to make and can be made anytime during or after the bench is built, and (2) round dog holes can be used with Gramercy holdfasts! Also, I have never seen square dog holes in vise jaws or bench aprons. So why not have a modern Roubo?

http://www.ncwoodworker.net/pp/data/1463/medium/IMG_2933.jpg

http://www.ncwoodworker.net/pp/data/1463/medium/IMG_29101.jpg

Paul Cahill
11-01-2011, 8:38 AM
To ask a very specific question. The traditional square dog and hole seems to work really well with a wagon vise to hold work for hand planing. Can those who have used both say if 3/4in round dogs work as well or at least close to as well as the square type in this role? Do they and the holes last well?

ian

Ian: I am not answering your question exactly, but I have both dog types in the bench I recently made (square on the front and a grid of round elsewhere for holdfasts) so I will give you my observations. In terms of just clamping a board, once clamped I don't see why there would be any difference between round and square. However, I find my home made square dogs are much easier to adjust height with than my homemade round dogs in the holes. I am sure I could come up with a better design on the round dogs, but for now I don't need to.


211631
Hope this helps.

Paul

Andrew Joiner
11-01-2011, 11:44 AM
However, I find my home made square dogs are much easier to adjust height with than my homemade round dogs in the holes. I am sure I could come up with a better design on the round dogs, but for now I don't need to.




Paul

I just tested round and square dogs for my new bench. I'm going with round dogs. I drilled shallow 1/4" dia holes into the side of each dog and glued in a 3/16 thick neoprene disk that's slightly proud. Rubber or hard foam would probably work too. The neoprene keeps the dog at the exact height. My abusive tests prove the neoprene won't wear out, but are easily replaced if they do.

Ian, If it's not to late, you can use a good metal quick release vise as an end vise without a racking problem. I tested this and although there is slight racking, it's not much. Boards held face up between dogs don't need much pressure to keep them in place.

Ryan Mooney
11-01-2011, 1:33 PM
I just tested round and square dogs for my new bench. I'm going with round dogs. I drilled shallow 1/4" dia holes into the side of each dog and glued in a 3/16 thick neoprene disk that's slightly proud. Rubber or hard foam would probably work too. The neoprene keeps the dog at the exact height. My abusive tests prove the neoprene won't wear out, but are easily replaced if they do.

Nice idea that's a fair bit easier than what I've been doing.

What I've been doing (dimensions approximate) is drilling a small (1/8") hole about 1" from the top and a smaller (1/16") hole 1/2" from the bottom and running a groove between them with a fine gouge or V tool. I have a collection of spring steel wire (used to hold insulation in place between joists) that I cut to length and bent into a elongated flattish U shape to fit in the holes/groove. The wire is hammered into the bottom hole which holds it in place and floats a little in the top hole (which just prevents it from sliding around). Because the wire is sprung out a little it grips the sides of the dog hole pretty well.

Your solution is obviously much simpler... now to raid the sewing room.. :D

Gary Curtis
11-01-2011, 1:37 PM
+1 on what Paul wrote.

Ryan Mooney
11-01-2011, 3:01 PM
I just tested round and square dogs for my new bench. I'm going with round dogs. I drilled shallow 1/4" dia holes into the side of each dog and glued in a 3/16 thick neoprene disk that's slightly proud. Rubber or hard foam would probably work too. The neoprene keeps the dog at the exact height. My abusive tests prove the neoprene won't wear out, but are easily replaced if they do.

Nice idea that's a fair bit easier than what I've been doing.

What I've been doing (dimensions approximate) is drilling a small (1/8") hole about 1" from the top and a smaller (1/16") hole 1/2" from the bottom and running a groove between them with a fine gouge or V tool. I have a collection of spring steel wire (used to hold insulation in place between joists) that I cut to length and bent into a elongated flattish U shape to fit in the holes/groove. The wire is hammered into the bottom hole which holds it in place and floats a little in the top hole (which just prevents it from sliding around). Because the wire is sprung out a little it grips the sides of the dog hole pretty well.

Your solution is obviously much simpler... now to raid the sewing room.. :D

Tom Hargrove
11-01-2011, 5:58 PM
I use 3/4" round dogs made from an oak dowel. I used on oak dowel because my bench is made from oak; any species will work. Some of them have a flat cut about 1/3 of the diameter into the top inch or so to allow for a greater bearing surface. I slide an O-ring on all of the dogs, which keeps them at the height I want with infinite adjustment.

glenn bradley
11-01-2011, 8:19 PM
I too use round and have for years. If you want more contact "face", sand a portion of the dowel flat.

ian maybury
11-01-2011, 8:28 PM
What a great line of replies. Nice benches Alan and Paul too. Thanks guys.

If I'm to summarise it seems that it's more or less unanimous that 3/4 in dogs in a decent hardwood definitely do the job, with no significant downsides. Other than that the stock square design with its built in spring gives very controllable height adjustment, and that a good spring solution is needed to get the same from the round type. I'm sure that can be achieved too. If the worst was to come to the worst it wouldn't be a show stopper to have to work through a few more spring types to get to one that sorted out.

That's great to hear, and was my original plan from about a year ago. Agree 100% on the flexibility/ease of adding round dog holes. I even have a set of four Grammercy hold fasts and a couple of 3/4 in twin lip Colt brad point drills I want to use. My sense was that the square dog appealed to the more traditional element.

The recent emphasis on square dogs in what i read got me a bit worried though - in that I started to wonder if the round type was strong enough (it's a significantly smaller cross section) or grippy enough/firmly enough located when placed in a vertical hole. A lot of squares are tilted to a the tail vice by a few degrees.

On choice of end vise/holding arrangements. I actually bought a large Lee Valley front vise last year intending to use it with a wide moving jaw and maybe three dog holes aligned with a grid in the bench top (like your twin screw Alan), but have been put off by the likelihood of this causing significant racking.

It's not too late Andrew, and I even have a Record 52 1/2 from the 1990s stashed away which I could use in a this role too. I know from using the Record that it's pretty stiff, but I wasn't too sure how it might do with a wider jaw, and offset dogs. It's a solid contender though, plan A say.

Plan B is to go for a wagon vise. I struggle with the thought of paying out €350 or whatever plus courier to Ireland for the albeit very nicely made Benchcrafted, but have figured that by borrowing the screw from the Lee valley front vise I bought and adding a more or less identical polished rim 125mm hand wheel I happen to have to hand, plus making up a set of rails and a baseplate I can replicate it for about €100. The result would be very, very similar to what you have Paul - Basically a Schwarz Roubo with a twin screw front, a dead man and a wagon vise - and the wagon vise layout suits the leg location on this design.

This (the DIY wagon vise) would be cost effective, and should work 100% at what it does. It'd need a set of Wonder dogs or similar to allow proper use to be made of a grid in the bench top though. It really does seem to be the dog's :) for the hand planing task though.

Plan C is the Veritas Q/R tail vise Mike. I'm increasingly confident about its build quality, while it delivers an extra over a wagon by clamping along the front face/across the legs of the bench like a tail vise too. The downside is the €260 plus shipping cost to me, plus it's got to be a bit more difficult to work around a Roubo style leg while maintaining a regular 3- 4in dog hole spacing - although the multi holes in the moving part sidestep it to some degree.

Here's a nice Roubo build with the Q/R tail vise: http://tiny.cc/0vpxr His jointing technique is interesting too, not to mention that he used round dogs.

So... One solved (the round dog holes), one to go. (the choice of end vise) Decisions, decisions....

Thanks again,

ian

Alan Schaffter
11-01-2011, 9:34 PM
What a great line of replies. Nice benches Alan and Paul too. Thanks guys.

If I'm to summarise it seems that it's more or less unanimous that 3/4 in dogs in a decent hardwood definitely do the job, with no significant downsides. Other than that the stock square design with its built in spring gives very controllable height adjustment, and that a good spring solution is needed to get the same from the round type.

ian

I may have missed it in your earlier posts, but unless you want to make your own round dogs from dowels, a spring is a non-issue. The Lee Valley brass dogs and pups (http://www.leevalley.com/en/wood/page.aspx?p=31127&cat=1,41637) shown below have a built-in spring. Remember the spring only needs to keep the dog from slipping down due to gravity so doesn't need to be strong. In fact it is nicer if the spring is not tight.

If you do plan to build your own wooden dogs, you can add a metal spring in much the same way as the Lee Valley dogs or a wood spring similar to what is done with square dogs.

One caution- take a fair amount of time laying out your dog holes, being careful to avoid areas where they might interfere with the frame of the base.

http://www.leevalley.com/en/images/item/woodworking/clamps/05g0401s4.jpg

ian maybury
11-03-2011, 9:22 PM
Thanks Alan, and sorry - I missed the post. So far the plan is to make my own dogs. It seems unlikely that coming up with a functional spring will be a show stopper with round dogs...

ian

Alan Schaffter
11-03-2011, 10:53 PM
Thanks Alan, and sorry - I missed the post. So far the plan is to make my own dogs. It seems unlikely that coming up with a functional spring will be a show stopper with round dogs...

ian

I haven't looked to see if it is on line, but there was an article in a WW mag years ago that showed how to make round dogs. Essentially, you start with a dowel of appropriate diam. Get some spring wire (Lowes, McMaster-Carr) and use a razor saw or other thin blade saw to cut a length-wise slit in the dowel slightly wider than the diam of the wire and about 1/8" deep. Drill a hole the diameter of the wire about 1" from the end of the dowel. Bend the wire like the spring wire in the Lee Valley dogs - in an "L" and epoxy the short end into the hole. Bend the long part of the "L" so it rides in the slit but the middle stays proud of the dowel.

ian maybury
11-04-2011, 12:15 PM
Thanks Alan, that sounds straightforward enough.

I seem to remember reading a piece somewhere which suggested that wire clips with time wear a groove in the dog hole - this was pitching the view that the flat spring strip is one of the advantages of the square type. I'm presuming you haven't seen anything like that.

Even if it was to become an issue over time, I'm sure it's possible to come up with a wide area spring for a round dog - although the big advantage of a wire spring is probably that it reduces the cross section of the dog by only very little.

ian

Alan Schaffter
11-04-2011, 4:49 PM
Thanks Alan, that sounds straightforward enough.

I seem to remember reading a piece somewhere which suggested that wire clips with time wear a groove in the dog hole - this was pitching the view that the flat spring strip is one of the advantages of the square type. I'm presuming you haven't seen anything like that.

Even if it was to become an issue over time, I'm sure it's possible to come up with a wide area spring for a round dog - although the big advantage of a wire spring is probably that it reduces the cross section of the dog by only very little.

ian

Havent' seen it yet. Again the spring doesn't need to be strong, it just needs to provide enough pressure to keep the dog from slipping down from the force of gravity. Only a bump or curve in the spring contacts the dog hole, so even if it does wear slightly it will likely be midway down in the hole where the bump is and then only if I use the same dog holes all day, every day. Also, I put a tiny chamfer on the top of the dog holes, making it less likely you would see a wear spot at the bench top. All this, of course applies to a hardwood top- a softwood top might indeed show some depression or wear if you used too strong of a spring.

By the way, here is a discussion (http://benchcrafted.blogspot.com/2010/06/talking-bench-dogs.html) of round vs square dogs by Jameel Abraham, designer of the superior quality "Benchcrafted" bench hardware. Very few of his points seem significant to me with the exception of - the metal vs wood issue when using a hand plane (if you are careless) and the ability to add round holes at any time, especially in vise jaws- a common occurrence.

In the other, round dog, camp is Chris Schwarz woodworker, author, lecturer, hand tool afficionado (zealot?), and former editor of Popular Woodworking Magazine. Here is what he says . (http://www.popularwoodworking.com/woodworking-blogs/chris-schwarz-blog/workbenches/i-have-a-dog-in-this-fight) There are some pics of his round wooden dogs- he uses bullet catches.

Here is a way to make round dogs (http://www.instructables.com/id/Making-bench-dogs-for-less-than-1/) - uses a flat instead of a groove for a flat metal spring.

Here is one that uses a flat wooden spring. (http://roughwood.kennethwoodruff.com/2010/03/making-bench-dogs/)

ian maybury
11-05-2011, 7:38 AM
Thanks Alan, good stuff. I initially read the topic up about a 18m ago, and influenced by Chris Schwarz decided on a hardwood (European beech in my case) Roubo with round dog holes. For the reasons he lists in your link - ease of addition of holes, large range of available accessories, ease of making, and possibility of use with holdfasts.

I concluded that square dogs were probably as much a matter of fashion/coming from a specific tradition as anything, and that if they have any advantage it's probably in the specific task of securing work for hand planing using a tail or wagon vise. But that they were a less flexible solution so far as holding other stuff is concerned.

This post came about because since then the Benchcrafted guys have gained a lot of profile, and there's been a lot posting of people using square dogs. I started to wonder if there wasn't some basic functional reason for this beyond fashion. Like strength, basic gripping ability or ease of use. The square dogs are for example quite a lot stronger due to having a larger cross section, especially compared to a 3/4 in round dog that's had a flat machined on it - which of course doesn't matter if the 3/4in round dog is strong enough. Square dogs likewise lend themselves to having an effective flat spring fitted.

The positive feedback about round dogs following my initial post seems to suggest that people are doing just fine with the round type, and that despite there probably being more of this type out there that there's no significant negative comment about.

So that barring negative feedback before then it's looking like it's round dogs for me when I get started on the bench in the next few weeks...

ian

Joe Leigh
11-05-2011, 8:20 AM
Ian,

If you are going with round dogs because they are easier, then you are making a mistake. Why is easier even in the discussion? If this is a "lifetime " bench for you personally why make compromises? Sure the square dogs are harder, a lot harder, and require more technique, skill and a lot more time to complete. Isn't that the point? Improving and learning while you build your bench as well as after you complete it? It took me two days to accurately make the jig required and to route out the dog holes and another day to fabricate 16 dogs. A very small investment in time considering that I have 3 months invested in my bench so far and at least another two to go.

Just my $.02

ian maybury
11-05-2011, 11:09 AM
Don't read this as saying the decision is made Joe, but the biggest reason I can figure for going round is that I'm keen to keep open the possibility of a pretty comprehensive dog grid on the bench top - to help with clamping awkwardly shaped assemblies like say laminated curves. There will also be a sliding deadman and possibly some holes in the legs and edge of the top to help with clamping on the front face. It seems a pity to pepper a bench with redundant holes, so I was hoping to add some of these as I went along.

Against that the square dogs seem to work really well with a tail or wagon vise to hold flat and square pieces for hand planing on the top. The problem with that though is that the traditional single row of square dog holes doesn't cater for the above. Not only that, but the 3 deg slope used on many square dog holes doesn't make them very adaptable to other tasks either. Mixing round and square holes seems possible but somehow awkward too.

I subscribe 100% to your point that there's no point cutting corners on what will be a lifetime job, but the 'easy' in this case is perhaps the ease of addition of extra holes after the top is built rather than labour saving - although I'll not turn my nose up at that either if the latter comes with no penalty.

That said, maybe there's an alternative way to obtain the above function?

My major caution about round dogs relates to the 3/4 in diameter - I've a sneaking feeling that something more like 1in would be more robust, and leave more options opening for putting flats on them etc. I've a feeling that a nice close fit in the bench holes to prevent tipping may be important too.

One problem with doing this is that so many accessories (Lee valley bench dogs and the like) use a 3/4 in shank. Steel holdfasts are usually 3/4 in in diameter, but you do see pictures of them used in quite loose fitting holes. http://www.flickr.com/photos/coalandice/3227486237/in/set-72157625264696890 I wonder how the latter would get on in a 7/8 or 1 in hole in a good thick bench top?

ian

ian

Alan Schaffter
11-05-2011, 1:19 PM
Ian- I agree with your very thorough analysis. I just have a few comments-

How much shear force is typically put on dogs? I would think enough force to snap a dog would also damage the work. I doubt it is necessary if the dog is made from good straight-grained hardwood, but I wonder if it would be possible the put a steel core in a wooden dog?

I forgot whether you have purchased your vise hardware, but since you mentioned the BenchCrafted wagon vise I'm thinking you are looking at the "good stuff." Have you checked out the Hovarter vises? Hovarter started with a simple face vise but now makes a full line of bench vises. They use a totally new mechanism that has a solid rod(s) instead of a lead screw, are quick acting, lock tight with less that a half turn of the handle, etc. The Hovarter twin screw (twin rod) vise and leg vise are totally rack free and the lower fulcrum on the leg vise adjusts and locks automatically! They are pricey like BenchCrafted.

Here is the link to the Hovarter web site. (http://www.hovartercustomvise.com/?page_id=37) You gotta see it in action. There is a video of the the twin screw (rod) vise on his website but there are videos of his other models on YouTube.

I have never seen a Hovarter vise in person, but I love technology and am a tinkerer as much as a woodworking. If I had the $ when I built my bench, I would have used Hovarter Vises.

Joe Leigh
11-05-2011, 3:19 PM
Well, the bottom line is that you have to make the decisions based on what type of work you do. Just ask yourself how often do you work with od sized pieces? 95% of the work I do is rectangular in shape and since I haved commited myself to using hand planes, the square dogs just seem right to me. Also, I've seen otherwise beautiful benches littered with rows of 3/4" holes like some horizontal pegboard.

Just a word about hold downs, you need to be aware of your top thickness if you plan to use them. Most Roubo bench plans call for a full 4" thick top and that can be problematic for the holding power of a hold down. Check with your specific manufacturer to see what thickness works best for them.

ian maybury
11-05-2011, 6:53 PM
What seems to be coming through from most of the posts here Alan is that 3/4 in dogs work just fine, the above is just my gut talking. I've seen the bench top thickness issue mentioned in connection with holdfasts too Joe. Test holes are probably advisable - it seems the things can be very unpredictable. I've a sneaking feeling as above that part of the issue is that they need to tip a bit in the hole to get a grip, and that a looser hole might work in a thicker bench top.

Part of the problem in my case is that I'm not well established enough as a woodworker to be able with any great certainty to be able to predict exactly the type of work that's I'm likely to gravitate to over time. Hence my attempts to keep some options open, although this isn't always a good move. Jack of all trades etc.

I've seen the Hovarter vise Alan, and it's very nice - but think I'm at this stage for budget reasons committed to the Veritas twin screw I've bought. I bought a front vice for the end, but have been put off by the risk of racking if it's used with a wide jaw and dogs. Right now it's between going to a DIY wagon vise in a format similar to the Benchcrafted, and rely on Veritas type dogs etc for more complex holding tasks - or possibly but less likely use a Record 52 1/2 I have with a wide jaw and dog holes. The Veritas quick release tail vise is another possibility, but again one requiring budget.....

ian

Alan Schaffter
11-05-2011, 7:39 PM
Well, dang, we need somebody to install and do a report on the Hovarter! :D :D

Greg Hines, MD
11-06-2011, 12:36 AM
I have round dogs in my bench, and instead of a tail vise, I use a pair of Veritas Wonderdogs to hold boards on the flat to rout edges or sand, and have had no trouble with them at all.

Also, there are plenty of different accessories that are generally easier to make with round dog holes. Lots of people make planing stops with a pair of dowels, and a board as the stop.

ian maybury
11-06-2011, 8:42 AM
:) I'll happily go guinea pig for you guys Alan if you'd just like to organise a little whip around there to get me set up....

Thanks Greg, another devotee of the round route....

ian