Sash bar dimensions for historical windows

[Jacob]

Oh, that's simple, Jacob: CAD to CNC machine, said a bit tongue in cheek.

But how do people do it without a proper drawing? The answer in my experience is; with difficulty, a lot of measuring and calculating, a jumble of notes, mistakes. Even if you have CAD produced scale drawings with every possible dimension shown you still have to transfer them one way or another.

Funnily enough I just last week disposed of my A1+ paper size parallel motion drawing board which I'd owned for about thirty years, it being a replacement for an older one. I took it to the charity shop. Somebody might buy it and use it, I suppose. I got rid of it because I hadn't used that drawing board for perhaps twenty years although I still have a small A3 drawing board plus all the drafting tools - squares, pens, compasses, scale rules etc. The truth is that I do 97%+ of my drawing digitally nowadays, mostly on Fusion 360, but there's still often a need to create from those digital drawings or orthographic projections full sized rods for the reasons you've given.

An irritant I experience with some designers/drafters who present you with digitally drafted working drawings is their unfamiliarity with the layout of orthographic projections. They're sometimes unaware of things like first angle or third angle projection and elevations and/or sections appear in odd illogical places along with occasionally presenting drawings that somehow randomly switch between first and third angle projection on the same sheet, which can lead to misunderstandings at the workbench... and even to errors in construction Slainte.

I picked up an A0 "drafting machine" when i was feeling particularly ambitious but never got into using it. Happier with an A1 sized board which I've had for 60 years! Never got into CAD/SketchUp, which would be useless for me without a very large printer.
For rods a drawing board not needed anyway - a little drafting skill comes in handy but at a very simple level, pencil sharpening etc

 

[steve355]

Saturday morning, just the 2 little vertical bars to cope, then I can finish it all off. But something looks wrong… the horizontal bar seems too long.

laying the rails on the rod, I have somehow got them the wrong length

It’s pretty hard to pick the correct line from the rod to be the tenon shoulder. Or easy to get it wrong. I need to work this out. I think the answer is usually “pick the line that leaves the most wood on the piece.”

Lesson - use the rod, all the time, to check and check again.

How annoying, I thought I was nearly done. I have to keep telling myself this is good experience and mistakes are made for learning from. Alternatively F******!!!!!.

 

[Jacob]

Saturday morning, just the 2 little vertical bars to cope, then I can finish it all off. But something looks wrong… the horizontal bar seems too long.

laying the rails on the rod, I have somehow got them the wrong length

It’s pretty hard to pick the correct line from the rod to be the tenon shoulder. Or easy to get it wrong. I need to work this out. I think the answer is usually “pick the line that leaves the most wood on the piece.”

Lesson - use the rod, all the time, to check and check again.

How annoying, I thought I was nearly done. I have to keep telling myself this is good experience and mistakes are made for learning from. Alternatively F******!!!!!.

View attachment 166375

Best to aim for 100% mark up at first, take them round all 4 sides and not miss out any lines which you think you might not need - sooner or later this will lead to a mistake.
After a while it becomes a routine and you read the lines like a bar code and get to know what you need.
Put wedge spaces in the mortices - it makes trial fits easier.

 

[steve355]

Best to aim for 100% mark up at first, take them round all 4 sides and not miss out any lines which you think you might not need - sooner or later this will lead to a mistake.
After a while it becomes a routine and you read the lines like a bar code and get to know what you need.
Put wedge spaces in the mortices - it makes trial fits easier.

I did try to do that. But I think that’s where the problem might lie. There is a line on the rod for the tenon shoulder and a line for the glazing rebate. What I am struggling with is using the correct one for the tenon shoulder. I think I need to perhaps only transfer the tenon shoulder line to the rail. Or perhaps mark the tenon shoulder line with a knife and the rebate line with a pencil (it’s depth is defined by the sash filister anyway.

The issue now is motivation! Must not give up.

 

[steve355]

By the way I’ve have a lot of success marking the coping lines on the bars with those templates I have, then coping with a coping saw. That part worked really well

 

[Jacob]

I did try to do that. But I think that’s where the problem might lie. There is a line on the rod for the tenon shoulder and a line for the glazing rebate. What I am struggling with is using the correct one for the tenon shoulder. I think I need to perhaps only transfer the tenon shoulder line to the rail. Or perhaps mark the tenon shoulder line with a knife and the rebate line with a pencil (it’s depth is defined by the sash filister anyway.

The issue now is motivation! Must not give up.

Maybe design issue - tenon shoulder usually same line as glazing and moulding rebate depth, with the flat as a second line i.e. depth of rebate away, if that makes sense, and instantly recognisable.
And get all face and edge marks on every piece and all facing same way - face to the moulding side and edge to the inside, also means you can match opposite pairs.

 

[steve355]

Maybe design issue - tenon shoulder usually same line as glazing and moulding rebate depth, with the flat as a second line i.e. depth of rebate away, if that makes sense, and instantly recognisable.
And get all face and edge marks on every piece and all facing same way - face to the moulding side and edge to the inside, also means you can match opposite pairs.

I think the design is ok but I’ve interpreted it wrongly on the wood. “tenon shoulder usually same line as glazing and moulding rebate depth” that’s specifically what I got wrong. I even drew a little arrow on the rod to make sure I got it right!

 

[Sgian Dubh]

But how do people do it without a proper drawing? The answer in my experience is; with difficulty, a lot of measuring and calculating, a jumble of notes, mistakes. Even if you have CAD produced scale drawings with every possible dimension shown you still have to transfer them one way or another.

CAD is a 'proper' drawing. With CAD you draw full scale and it's only at the printing stage that the drawing has to be scaled to print on paper. For example, to fit on A3 the scale could be 1:5 whilst for A1 you might be able to scale at 1:2.

As to getting parts worked on CNC machines, in essence, you isolate items from the drawing using, for example, layers, and in this case we'll say a barley twist leg, feed that information into the computer that controls the CNC (sometimes using an intermediary programme to create the requisite code from the CAD drawing) and machine up a piece of wood large enough for the leg. Then this lump of wood is attached between centres on the CNC machine, make sure all the right cutters are available in the tool holder, and push the start button, along with turning on the extraction.

Next job is to go to the kettle, boil it, make tea and drink it whilst the CNC machine does its job, and get ready to remove the machined part and mount the next bit, and press start again. Of course, instead of making and drinking tea whilst the machining is going on, most workers do something productive elsewhere in the workshop between mounting blanks and removing machined parts, assuming there aren't any mishaps during the machining process, and mishaps certainly do occur as I can testify. Slainte.

 

[Jacob]

CAD is a 'proper' drawing. With CAD you draw full scale and it's only at the printing stage that the drawing has to be scaled to print on paper. For example, to fit on A3 the scale could be 1:5 whilst for A1 you might be able to scale at 1:2.

As to getting parts worked on CNC machines, in essence, you isolate items from the drawing using, for example, layers, and in this case we'll say a barley twist leg, feed that information into the computer that controls the CNC (sometimes using an intermediary programme to create the requisite code from the CAD drawing) and machine up a piece of wood large enough for the leg. Then this lump of wood is attached between centres on the CNC machine, make sure all the right cutters are available in the tool holder, and push the start button, along with turning on the extraction.

Next job is to go to the kettle, boil it, make tea and drink it whilst the CNC machine does its job, and get ready to remove the machined part and mount the next bit, and press start again. Of course, instead of making and drinking tea whilst the machining is going on, most workers do something productive elsewhere in the workshop between mounting blanks and removing machined parts, assuming there aren't any mishaps during the machining process, and mishaps certainly do occur as I can testify. Slainte.

But how do you do it without the CNC machine?
Lots of people using SketchUp for instance and then work stuff by hand.
I use PT, spindle, mortice machine, but the actual process and marking up is much the same sequence as for 100% hand tool work - which I've also done many times.

 

[Sgian Dubh]

But how do you do it without the CNC machine?

It's done the same way as taking information from any other drawing. CAD drawings from, for example, Fusion 360 can print out 3D rendered perspectives as well as producing dimensioned orthographic presentations of elevations and sections. Alternative CAD programmes have similar capabilities, some better than others, no doubt. I can't comment on the capabilities of programmes of which I've no experience.

To be honest I'm not sure I understand your question because if I need to make full size rods, for example, accurate information provided by orthographic projections have always sufficed, although a good perspective sketch or drawing is always helpful. Maybe I don't fully understand your question because my field is primarily free standing and built-in furniture rather than joinery products such as windows, doors, stairs, and so on. Slainte.

 

[Jacob]

It's done the same way as taking information from any other drawing. CAD drawings from, for example, Fusion 360 can print out 3D rendered perspectives as well as producing dimensioned orthographic presentations of elevations and sections. Alternative CAD programmes have similar capabilities, some better than others, no doubt. I can't comment on the capabilities of programmes of which I've no experience.

To be honest I'm not sure I understand your question because if I need to make full size rods, for example, accurate information provided by orthographic projections have always sufficed, although a good perspective sketch or drawing is always helpful. Maybe I don't fully understand your question because my field is primarily free standing and built-in furniture rather than joinery products such as windows, doors, stairs, and so on. Slainte.

I'm asking how you get to make marks on workpieces for the purposes of cutting mortice and tenons and everything else.
With a rod it's easy - you drop the pieces on and take marks straight off with a set square (though there are variations).
Without a rod you'd have to take them from the drawing as annotated or calculated, keep notes and put them on the workpiece with help of a tape measure etc.
You could make a "story stick" but you couldn't do it easily without a rod to start with.
Same for furniture as for windows/doors etc.
So for instance if you have a stack of stiles with 2" long mortices do you measure for each one or what?

 

[Sgian Dubh]

I'm asking how you get to make marks on workpieces for the purposes of cutting mortice and tenons and everything else.
With a rod it's easy - you drop the pieces on and take marks straight off with a set square (though there are variations).

I thought I'd answered that where I said, and I quote:

... if I need to make full size rods, for example, accurate information provided by orthographic projections have always sufficed

I don't know of any other way to make a rod from a scale working drawing (e.g., orthographic projection) printed on paper, or the same drawing viewed on a computer monitor, e.g., laptop. Slainte.

 

[Jacob]

I thought I'd answered that where I said, and I quote:

I don't know of any other way to make a rod from a scale working drawing (e.g., orthographic projection) printed on paper, or the same drawing viewed on a computer monitor, e.g., laptop. Slainte.

But having drawn up a rod do you then mark up by laying pieces on and marking directly, without measuring anything?

 

[Sgian Dubh]

But having drawn up a rod do you then mark up by laying pieces on and marking directly, without measuring anything?

Yes, for those parts for which a rod is created. Otherwise why bother making a rod? Having said that it's quite commonly a case of making a rod for a carcase and then using the dimensions of the assembled carcase itself to fit parts to the openings and spaces within, e.g., doors, drawers, shelves, and so on. Slainte.

 

[Ollie78]

Off topic, but a couple of posts a while back were talking about adding lead weights to the existing iron rather than getting bigger iron weights for sash double glazing upgrades. (Mine are Edwardian 1908 and very simple boxes).
When I get round to go looking, what are these called?

Just buy the lead as 1200mm bars in a suitable dimension, you can cut it on a mitre saw no problem.
Buy it directly from Heaps Arnold and Heaps, everyone else just buys it from them and charges you more for it. Especialy if they have cut it smaller for you.
I normally just get rid of the iron weights and switch for lead as you are almost doubling the weight of a sash so travel will be restricted by adding on to the lighter iron.


Ollie

 

[Jacob]

Yes, for those parts for which a rod is created. Otherwise why bother making a rod? Having said that it's quite commonly a case of making a rod for a carcase and then using the dimensions of the assembled carcase itself to fit parts to the openings and spaces within, e.g., doors, drawers, shelves, and so on. Slainte.

So that's not quite the rod full monti. Half way there!
With a trad rod all the components are drawn in on to the one same rod (with as much detail as needed) and then measurements all taken off directly from the rod only, not from each other, nor from measuring (except for the cutting list perhaps).
Then the cutting list for all (even if its say 10 sash windows or chests of drawers with 100s of components)
Then all the dimensioning in one act, all the marking, all the morticing, tenoning....etc and all will fit.
The rod system is so accurate that after you've drawn up the rod you can order the glass for the windows cut to size , even before you've started the woodwork.
Some joints might need easing or fine adjusting but basically the system is close to error free and very fast.
Different sizes might mean separate rods but if the details repeat you might be able to superimpose one on the other and still have just one rod drawing

 

[HOJ]

In my view "rods" were purposeful in the era that they were more commonly used, drawings, sketches etc were drafted by Architect's or Designer's, and when a commission was received then the rod was laid out to be given to the relevant maker/s for production, which would very well be geographically distant, again, in my view, the craftsman maker was skilled in the making of what was conveyed by the rod but not well educated, as in reading and writing, therefore the information was graphical and not technical.

I do make rods as outlined before but only where I need to understand complicated detailing, I wouldn't make one for standard projects, In this day and age the time spent making a rod is a complete waste of time when the education/training/knowledge/skill/CAD/software is used to optimise production.

With no disrespect to @steve355 the rod hasn't proved itself to be faultless, whereas if he had measured off it may have been more apparent where the line/s should be drawn!

 

[steve355]

With no disrespect to @steve355 the rod hasn't proved itself to be faultless, whereas if he had measured off it may have been more apparent where the line/s should be drawn!

For me it’s been extremely useful actually. These joints and how the whole thing fits together is simple in principle, but in detail and in practice it is much harder. I think it’s partly my inexperience in using the rod. For example, I got both rails wrong. Had i carefully laid the first rail on the rod after I had made it, I would have realised it was wrong and would not have messed up the other rail.

And I need to work out a way to ensure that the lines on a horizontal piece that mate with a vertical piece are clear. perhaps next time I do it I will use a different colour for these lines.

Another difficulty I’ve had is transferring the marks from the rod to the wood accurately.

Overall it’s a pretty laborious process but designed to get an accurate result. I like it. I just need to get better at it.

I’d also say though that the actual amount of woodworking is pretty low. I’m dimensioning and planing all of my stock by hand. The time to do this and then mark up greatly exceeds the final woodworking operations.

 

[Jacob]

....

With no disrespect to @steve355 the rod hasn't proved itself to be faultless, whereas if he had measured off it may have been more apparent where the line/s should be drawn!

First attempt!
In the end it is highly productive. Drawing up the rod doesn't take long (if you know what you are doing). The marking itself can be protracted - but eliminates error (if you know what you are doing).
So far nobody has quite explained how, in a small workshop, you get from CAD to marking up your workpiece, except
Sgian Dubh but he only goes part of the way

 

[Jacob]

.....

Another difficulty I’ve had is transferring the marks from the rod to the wood accurately.

Set square and 2H pencil, against a stack of components. Mark one side (usually all edges as marked) and then take the marks around all 4 sides piece by piece, with a square.

https://www.ukworkshop.co.uk/thread...historical-windows.144044/page-5#post-1681321

I’d also say though that the actual amount of woodworking is pretty low. I’m dimensioning and planing all of my stock by hand. The time to do this and then mark up greatly exceeds the final woodworking operations.

That's the idea. All the measurements and design decisions are made in the first phase and then you are on auto pilot.