Infill plane design questions

[Mark Baldwin III]

One project that I will not get out of my head until I finally do it is my own infill plane. What I want to make is a plane of approx. 5.5" length with a 1.75" iron.
Planning on 1.5" sides with an "overstuff" bringing the side height up a little over 2". 50 degree cutting angle. The last design point would be putting the mouth at about 1.75" from the leading edge.

All of those measurements are approximate...and are my starting point. There are, however, a few dimensions that I feel may be too important to be left to chance. At the moment, I can do everything except turn the lever screw. Once I have my lathe back up and running, I'll be able to take care of that.

Since I know several members here have made their own infills, I am curious if anyone may have some rule-of-thumb, or general guideline measurements for my three missing dimensions: a,b, & c as shown in the picture: ("a" being the angle between the lever and iron, "b" being the distance from the center of the lever pivot and screw, and "c" being the distance from the bottom of the plane to the pivot of the lever)

[don wilwol]

I'm by no means an expert, but I've always marked the levercap holes by placing the iron in place as part of the layout. The iron and chipbreaker thickness and the lenght of the lever cap will dictate where the hole needs to be.

[Zander Kale]

(BC)I give the screw 1:1 or more leverage but scale it to the length of the cap, usually by eye.
For example (front to pivot : pivot to screw), 5/8":3/4", 7/8":7/8", 1":1.5" (2), 1.25":2".
(A)I definitely like less than 1/2" between the back of the cap and the blade, somewhere between 3/16" & 3/8".
Another thing I'm anal about is the that the angle of the screw to blade be 90°. I either bend the cap or drill at an angle (examples of each in the photos).

tiny cap.jpg1.jpg screw1.jpg close.jpg cap top.jpg

[Mark Baldwin III]

Zander- That is exactly the kind of info I was looking for. Thank you!
That is some gorgeous work you have there. I'm starting much simpler, maybe one day I can get real artsy.

[Mark Baldwin III]

I'm by no means an expert, but I've always marked the levercap holes by placing the iron in place as part of the layout. The iron and chipbreaker thickness and the lenght of the lever cap will dictate where the hole needs to be.

The iron is part of the layout. I'm keeping this idea simple with a single iron. I've made several plane irons, and all have been singles. I haven't made a back iron yet. Maybe after I've done this a few times...

[Mateo Panzica]

There really aren't any rules of thumb here... but, if you get something way out of wack, it could get funky.
For what it's worth, this is what I do:

I make the value of A to be 2 1/2 - 3 degrees more then my blade angle. In your case something like 53 degrees.

I make the length of B slightly more than A. My planes often have 1 1/2'' sides. It often works out to C = 11/16'' and A = 3/4''. At times I've made them equal lengths and found no problem with that. It all has to do with where you want that hole in the side of your plane and how high you want the screw. It's something that you can play around with.

Here's one of my lever caps in action.110 7.jpg

[Mark Baldwin III]

Mateo-That is a beautiful plane. Very "technical" looking...for lack of a better word. It looks like you're using brass to form the bed. That's a a neat idea.
Your cap screw is the show piece of that plane (to me, anyway). I really like the execution.
Like you say, there is room to play. I am looking for a general starting point. As you well know, there are plenty of places to go wrong. So I am just searching for ideas to help me home in on something to start with.

For the record, I will probably rough out most of the work with my mill. After that I will file the dovetails by hand and hammer it all in. I don't feel the need to go completely by hand on something like this if I have a mill in my basement with which I can do 90% of the work. I don't know how well everyone's memory around here is, but I had ordered a hand made infill a couple of years ago and got ripped off (that maker has since dropped off the face of the Earth). I wanted that plane for two reasons...one was to have a sample to study, second was the sheer art of it. Since then, well...I haven't been making tools.

Much respect to you gents...and ladies (if there are any)...who make these things. Infill planes are my favorite blend of art and tool.

[Ron Brese]

Mark, all the other dimensions aside, I think the foley in your design may be in the width of the iron for a plane of that length. A 1.75" wide iron in a plane that does not have a tote can be very hard on your wrist. When I initially proved the design on my 650-55 and 650-55J plane my first inclination was to make the same plane just by increasing the proportions to accommodate a wider 1.75" wide iron. I made a prototype and it was immediately apparent that the increased width was going to be hard for someone with average size hands to hold and use. I made one project using that plane and the design never went any further than that. Long story short, it hurt my wrist to use that plane for any length of time. I think a 1.5" wide iron is the maximum comfortable width for a plane of that configuration.

Ron

[george wilson]

You've probably got enough replies to do you. Here are some of mine,plus a shoulder plane that doesn't count here,but it is a very cool design which you are welcome to copy. Comfortable to use,too.

I didn't leave a lot of clearance beneath the cap screw on the two that have them. But,you need enough to be able to extract the iron and chip breaker. Especially if the chip breaker has the rather tall,domed brass nut on it,as mine do.

The small plane is a copy of a 1/2 size apparent salesman's sample I saw. It was quite rare and expensive. Too expensive for me! So,I built a copy when I got back. And YES,it is the only plane I have ever seen that has the sacrificial screw(which you whack on to back off the iron,to save beating the body of the plane) on the FRONT! Tapping on it would advance the plane blade,rather than retract it. Maybe some 19th. C. . inventor's idea? It is a plane I have used,though only 4" long with a 1/16" thick iron with a chip breaker the same thickness. But,fun to use,at least on softer type woods.

The two iron body planes are dovetailed together. Even up the front edges on the small plane. Rosewood infill on both the small plane and the shoulder plane. Stained mahogany on the smooth plane. Stained too dark! But,I was in my 20's then.

Just under the cap screw on the smooth plane,you can see the brass "nut" on top of the chip breaker,which some nicer English planes had. To lengthen the depth of thread,and also to make the chip breaker nut easier to tighten,brass being a slippery metal. But you need clearance for that when you pull the blade out from under the cap screw.

The cap screw on the smooth plane is too thick to have knurled. I filed the knurling on to that screw,but it is about impossible to tell that it wasn't knurled in the usual way.

The shoulder plane has an adjustable throat. The adjustable throat must be removed to extract the blade. A small bit of trouble,but I didn't want to have to make a huge escapement so you could tilt the blade up and remove it. I preferred the more graceful design here,which flows with the shape of the top edge of the plane's body.

The "Overstuffing" makes this plane so easy on the palm of the hand. That and the rounded design at the rear. 19th. C. planes,especially shoulder planes,did not make much effort to be easy to push. I wanted mine to be more comfortable. I made more than 1 of these planes when I was Musical Instrument Maker(I know,they aren't 18th. C.!) But I cared more for designing things in some details of the shop. I never was "addicted" to emulating 18th. C. things as some were. Personally,I think the Zenith of tool making was in the 19th. C.. Some beautiful things,especially flintlock guns reached their Zenith in the 18th. C.. Guns became more "slab sided" in the 19th. C.. But,tools had a way to go. 18th. C. harness hurt horses some. This was corrected in the 19th. C.. Different evolution for different objects.

I made more than 1 of many in my night time home shop doings,because tool collectors would come into the shop and beg me to sell them tools on my bench!! Well,a bit of extra money didn't hurt. I was re equipping my very small(at that time) home shop,to work metal instead of wood. I didn't have the space to make guitars,nor did I want to raise the dust. My little shop was right off the living room,and was about 6' x 10'. I had just enough space between my bench lathe and my work bench to stand and file,etc..

Things like these unknowingly to me ,led my director to begging me into establishing a tool maker's shop. I had had enough of being in public after 16 years,answering the same questions. And being jumped on by an occasional old fool who just KNEW we were doing everything wrong! One was convinced that only the Chinese knew how to cast brass,so I just COULDN'T have those brass violin planes. He was in his 80's and very aggressive. I didn't know how to deal with such ignorance,at such a basic level, and we weren't supposed to argue with tourists. I couldn't remember brass cannon,brass candle sticks,or anything. I didn't know WHERE to start with that character!! Age DOES NOT guarantee wisdom! Another old duff who apparently taught copper working in a school became totally indignant when he was told that the 18th. C. fire engine that we built had a copper air tank(as did the original!) He toured the town looking for the copper smith shop,which he had been told did not exist. (The silversmith made the copper tank.) He acted like he had the patent rights on working copper!!! Some guys just go nutzo. Well,to heck with that stuff! The toolmaker was behind the scenes!

Mateo: Might want to round the rear of that plane to keep from making blisters in the user's palm!

[Mark Baldwin III]

Ron and George-
Thanks for the additional tips. Much appreciated.

1.75" iron width isn't a hard number. It is the width I decided to start the design with. Since I haven't started cutting anything yet, it's all open to change. I have a 55 degree Krenov style plane that I made with a 1 5/8" iron. It is 5.5" long, and an absolute bear to push. Been wanting to remake that one, as I've never really been able to tune it in. My 9" long plane has a 2" wide iron and a tote (50 degree, I think)...another very early plane I made. I hate it! Every now and then I pull those two planes out and try to tune them in, but they keep beating me. I did both of those without really consulting or listening to experts first. Hence the questions now.

Thanks for being open about the craft. Sometimes it's hard to reveal "trade secrets".

[Derek Cohen]

One project that I will not get out of my head until I finally do it is my own infill plane. What I want to make is a plane of approx. 5.5" length with a 1.75" iron.
Planning on 1.5" sides with an "overstuff" bringing the side height up a little over 2". 50 degree cutting angle. The last design point would be putting the mouth at about 1.75" from the leading edge.

All of those measurements are approximate...and are my starting point. There are, however, a few dimensions that I feel may be too important to be left to chance. At the moment, I can do everything except turn the lever screw. Once I have my lathe back up and running, I'll be able to take care of that.

Since I know several members here have made their own infills, I am curious if anyone may have some rule-of-thumb, or general guideline measurements for my three missing dimensions: a,b, & c as shown in the picture: ("a" being the angle between the lever and iron, "b" being the distance from the center of the lever pivot and screw, and "c" being the distance from the bottom of the plane to the pivot of the lever)

Hi Mark

A few observations.

My anticipation is that a smoother with a 5 1/2" length and a 1 3/4" wide blade is going to be awkward to push. This will be increasingly so as the bed angle rises. Ron made this point as well. The closest I have to your plane is a kit I put together from Ron. This is a 6" infill with a 1 1/2" wide blade and a 60 degree bed. Overall, the plane is well-balanced, although the high cutting angle (single iron) does demand more effort. This is mitigated somewhat with a dab of wax on the sole.





You are looking at a 50 degree bed. This angle is one that I consider (especially for our local hardwoods) to be neither-here-nor-there, that is, it does not make a significant difference to warrant the extra resistance. I would rather make a plane with a lower bed and use a double iron (using the chipbreaker to control tearout). This takes some of the pressure off getting a fine mouth since the design benefits from a slightly wider mouth for chip clearance.

If you particularly want a plane around 5 1/2" long, then the blade width will need to be around 1 1/4", and I just do not see the point of this. I do have a plane like this - HNT Gordon Small Smoother - but, while useful, it has a very limited range. I would treat 1 1/2" as the lower limit and ideally look for 1 5/8" or 1 3/4" as the maximum in a useful small smoother. But then you need to look carefully at the length and bed angle.

The only other infill I have built that is around this size was one using a Stanley #3 body. The relevance of this is that the bed angle is 25 degrees (the blade is bevel up, so a 35 degree bevel creates a 60 degree cutting angle). The blade is 1 3/4" wide and the body is about 8 - 8 1/2" (I cannot recall exactly). Again, this is a very balanced combination and it is, in fact, easier to push that the Brese (of the same cutting angle). I think that this is partly down to the lower bed/body and the width-length ratio.


With regards placement of the levercap, there just needs to be enough space for the blade to be inserted/retracted. Then it comes down to what you consider to be aesthetic.

Placement of the mouth? I defer to the likes of Ron. They have much more hands-on experience with design. The kit (above) has its mouth about 25% back (Ron can correct me here - I speak from looking at the picture below) ..






The Stanley is about 1/3 back. I would look at Stanleys for a tried-and-true formula. I have found that characteristics change as the mouth position is shifted.

Regards from Perth

Derek

[george wilson]

Derek,last year(or so),I got hold of a Stanley #4 body,inspired by your Stanley infill.Your idea of using an old Stanley body is very cool to make a quick plane (No dovetailing!). I intend to mill the insides of the body out to make everything nice and flat and to fit the infill. Then,I'll modify the shape of the body with my die filer. Not that the original shape is bad at all. It will be an opportunity to do a bit of design work,though,which is my favorite part of tool making where I can use my own imagination.

Not that I need another plane. I just like the idea of using a Stanley body. It'll be fun to see what I can turn it into.

I also got a #3 body,but find it pretty narrow,but still a candidate for another infill. Now that I realize your plane was a #3,I feel more encouraged to use it. You must have spend some time with a file on the inside of yours.

[Derek Cohen]

Thanks George.

The only machine tools I had were a 4" grinder and a Dremel. Otherwise it was just files. The parallel blade came out of an old ECE woodie. The brass in lever cap was the hardest brass I have ever attempted to work! The screw was one of my "inventions"

The reason for the 25 degree bed was an attempt to determine whether a higher bed would reduce the wear bevel - I cannot answer that since all planes incur wear bevels on both sides of the blade. What I can state is that this is one of the sweetest smoothers I have ever used. It's performance is up there with the very best.

I'm looking forward to your creation - I know it will be special.

Regards from Perth

Derek

[Mark Baldwin III]

Derek- I've always thought that your #3 infill was a creative idea. A nice end-around for building a body.
A smaller, block type plane is on my list.

This is about process for me, learning new stuff. And something to do to help me quit smoking
That and I just like making stuff. Whatever it is.