There is (was?) a book called Takboken or something similar. It came with a diskette containing a program called Takbok where you could test different dimensions. I borrowed the book from the library once upon a time.
Here you can find it:
Takstolsboken - Bokus bokhandel
Takstolsboken - Bokus bokhandel
Was that so?
I seem to recall that you could input certain parameters, such as span width, and then receive a drawing with detailed images of nodes, etc.
But as I said, you couldn't choose an excessive number of different parameters, so the program is quite limited in my opinion...
Then there's the Kartro program. I've never tested them myself, and I imagine they are quite expensive...
Kartro CAD-system
I seem to recall that you could input certain parameters, such as span width, and then receive a drawing with detailed images of nodes, etc.
But as I said, you couldn't choose an excessive number of different parameters, so the program is quite limited in my opinion...
Then there's the Kartro program. I've never tested them myself, and I imagine they are quite expensive...
Kartro CAD-system
I have Takbok 2004 and I agree that there are a lot of limitations. It is definitely not a universal program that creates the exact truss you want, unless you are very lucky.
I am attaching an image that describes the program's capabilities. The roofs listed first allow you to choose a pitch of 14° or 27°, nothing else.
The program considers climate zone, snow, and wind load; you simply specify which location it concerns from a selection list. However, I have forgotten to check if the new climate zones are included.
The program also calculates where nail plates and nails should be placed and the number, but there are only four sheet metal brands to choose from.
Drawings and load calculations are the "output."
There are also some minor limitations in support width and span (both downwards and upwards).
But the program is quite good if you can choose the recommended roof angle. Otherwise, it's excellent for experimenting a bit with truss types to see where the dimensions are heading, and in the end, you might still order prefabricated and strength-calculated ones from a company.
I am attaching an image that describes the program's capabilities. The roofs listed first allow you to choose a pitch of 14° or 27°, nothing else.
The program considers climate zone, snow, and wind load; you simply specify which location it concerns from a selection list. However, I have forgotten to check if the new climate zones are included.
The program also calculates where nail plates and nails should be placed and the number, but there are only four sheet metal brands to choose from.
Drawings and load calculations are the "output."
There are also some minor limitations in support width and span (both downwards and upwards).
But the program is quite good if you can choose the recommended roof angle. Otherwise, it's excellent for experimenting a bit with truss types to see where the dimensions are heading, and in the end, you might still order prefabricated and strength-calculated ones from a company.
If you can get hold of the predecessor to the "Takstolshandboken" (Wood Roof Trusses for Residential Buildings) at some antiquarian bookstore, you have all the formulas needed to design your roof truss. It's then easy to input the formulas into a calculator with your parameters, and out comes a finished roof truss.
There is, however, a drawback to doing so: you don't really know what you're doing, and you wouldn't know either if you use a computer program for the same thing that is based on the same formulas. The only advantage of the calculator is that it is independent of the roof slope. You can therefore choose the angle freely. You also have to be aware that only the types of roof trusses specified can be calculated in this way.
Normally, roof trusses were previously calculated statically by 'hand work'* with these formulas or a graphical method was used where scale lines represented the external forces. How it works nowadays, I know nothing about. (I don’t think, for example, that they teach in high school how to draw a Cremona on a W-truss today.)
The curse of computers/programs is that the user does not become smarter but dumber as a designer, and it also shows when I get hold of a design made with these so-called aids. And how will the result not be when an amateur without a background in statics and strength of materials uses them?
__________________
The builder
*) paper and pencil + slide rule.
There is, however, a drawback to doing so: you don't really know what you're doing, and you wouldn't know either if you use a computer program for the same thing that is based on the same formulas. The only advantage of the calculator is that it is independent of the roof slope. You can therefore choose the angle freely. You also have to be aware that only the types of roof trusses specified can be calculated in this way.
Normally, roof trusses were previously calculated statically by 'hand work'* with these formulas or a graphical method was used where scale lines represented the external forces. How it works nowadays, I know nothing about. (I don’t think, for example, that they teach in high school how to draw a Cremona on a W-truss today.)
The curse of computers/programs is that the user does not become smarter but dumber as a designer, and it also shows when I get hold of a design made with these so-called aids. And how will the result not be when an amateur without a background in statics and strength of materials uses them?
__________________
The builder
*) paper and pencil + slide rule.
Hello Builder and thanks for the insightful answer! As always... 
I understand what you mean by: "you don't really know what you're doing and you don't know that even if you use a computer program for the same thing based on the same formulas."
I myself really like the computer and have relatively good knowledge in strength of materials, so I will probably go with Chinaski’s suggestion - Takstolsboken. But it is clear; paper, pen & calculator are clearly underrated nowadays (never got around to the slide rule).
As I have hinted in other threads, I usually oversize the home constructions a bit to be on the safe side. Then of course aesthetics also have to guide a bit
I understand what you mean by: "you don't really know what you're doing and you don't know that even if you use a computer program for the same thing based on the same formulas."
I myself really like the computer and have relatively good knowledge in strength of materials, so I will probably go with Chinaski’s suggestion - Takstolsboken. But it is clear; paper, pen & calculator are clearly underrated nowadays (never got around to the slide rule).
As I have hinted in other threads, I usually oversize the home constructions a bit to be on the safe side. Then of course aesthetics also have to guide a bit
You should be glad you missed out on the slide rule. It was called the 'guessing stick' because you had to keep track of the number of zeros and place the decimal point yourself, so it was quite a hassle remembering how many times-to the left and right-with-the-stick for it to be accurate and not guessworkpeegee4 said:---
I myself am a big fan of the computer and have relatively good knowledge in strength of materials, so I will probably go with Chinaski's suggestion - Takstolsboken. However, it's clear; paper, pencil & calculator are definitely underrated these days (never got around to using the slide rule).
As I have hinted in other threads, when doing DIY projects, I usually over-dimension a bit to be on the safe side. Then, of course, aesthetics must also govern a bit
Sometimes you need to over-dimension. Especially if the construction looks 'flimsy'. On the other hand, it can lead to the self-weight being too high and requiring an even greater dimension in the structural part subject to bending force.
To over-dimension a bit to be on the safe side is more a sign that the designer/statician doesn't trust their own calculations or used formulas
And even though I also really like the computer, I don't trust it unconditionally
Especially not in contexts like strength calculations.And even if you have good knowledge in strength of materials (the study of internal forces), you must have at least equally good knowledge in statics and dynamics (the study of external forces at rest and in motion). Otherwise, the former is of no use to you.
_________________
The Builder
do you think it can also handle saxtakstolar?vedeldaren said:
No. Scissors trusses are not approved in Sweden due to static indeterminacy because there is no closed triangle at the top.Snailman said:
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Byggaren
do you mean these would not be approved?
Saxtakstol - Sepa
Takstolar Takstol i Nässjö och Småland - Nässjö Takstolsfabrik AB - Takstolsfabrik
I have also seen such used quite frequently in housebuilding blogs
Saxtakstol - Sepa
Takstolar Takstol i Nässjö och Småland - Nässjö Takstolsfabrik AB - Takstolsfabrik
I have also seen such used quite frequently in housebuilding blogs