Home made roof trusses
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- Опубліковано 8 вер 2024
- Home made roof trusses using a home made press.
The press uses a 12T bottle jack. The usual press uses 20T, but I find that 12T is ok. These trusses have been calculated for 60 lb/sqft of snow load (Add to that a 7.5lb/sqft of dead load). These are half trusses. They will be jointed using steel strap ties.
The trusses will be installed in a garage/shed/workshop, not a home.
The frame of the press is made using 1'' (25mm) plates and 3/4'' (19mm) flats. The flexion of the press frame at max pressure is about 1/8'' (3mm). Which is acceptable. A stiffer frame would be much heavier. This one is already not a pleasure to move from joint to joint.
The truss you see took me about 1h30mn to make, and it was over 28 deg. Celsius this day.
Nice work.
This is awesome! I have a couple of ideas for this too. Weld the top of the jack to the press you built closer to the outside so you have plenty of room when pressing the plates. Add some wheels so the bottom of the press comes up around saw horse height. Use saw horses to hold the trusses in place so they overhang where the plates will be installed. Then you can wheel around the press to each plate and it would be sooooo much easier. You did a great job on that press build though. Looks very sturdy!
This is awesome!!
You should be able to do both plates at the same time I would imagine, Good concept though.
Pretty slick. Going to build one of these. Thank you for sharing. 👍🏻
Awesome job 👍
While you are getting it done and it looks like it will work for your shed, there is a lot more that goes into proper truss design and construction. For starters, spruce or white wood is not acceptable to code for structural trusses. It all has to be yellow pine and your different pieces have to be different grades. For example, the top and bottom chords would be no.1 or SSDense, the vertical end would be no. 2 prime, and the webs would be no. 2 or no. 3. Im sure there are some places in the small trusses that would be just fine with 2x3 webs, but not in a truss of this size. I believe that your plates are also undersize for several of the joints and may not be at the correct orientation.
These trusses would never pass a building inspection in my state and would not be allowed for use in any permitted structure.
It seems like there has to be an easier way to press the gussets into the wood (without an uber-expensive roll press table). I'm envisioning a table on which the chords are are arranged into the truss and the surface has holes and slots to affix jig stops and fulcrum pockets. If I am doing any number of trusses, I am going to want a table regardless for the assembling. A fulcrum of a manually operated crimping press can be inserted into a fulcrum pocket adjacent to a junction sandwiched with gussets and then the gussets could be pressed into the wood using manual pressure with a long lever. The pocket, crimper and lever would be way lighter and easier to move around and manipulate. I didn't pay enough attention in physics to calculate out how much pressure can be achieved with such a system (and of course it varies depending on the size of the lever), but if they have manual presses that can fabricate compressed earth bricks, I imagine crimping some gussets is doable.
I'm not saying that it isn't doable by hand, but it won't be easier. We use a handheld hydraulic press mounted overhead on a rolling trolley. It is balanced just right so that it will hang in the air where you leave it. The counterbalance is the electric pump and hyd. fluid reservoir.
Really like this method. But i have some burnt trusses i would like to repair with out replacing the truss. I have 16 on centers so i would need to make something smaller
can you share calculation for trusses?
This is hard and time consuling work. Why you do not use magnets for holding bottom plates under the boards? This will save you some energy and time. Thanks.
I am a mechanical fitter, that rig looks to be twice the weight that it needs to be. My back hurts watching you work.
Hey David, I’m looking to weld a setup like his. I would like to make a lighter setup. Do you have any suggestions?
@@ag1985ch1 I have used an I Beam as the back bone 10mm plate welded at the bottom the top plate is welded to the face of the beam with with a 10x40 mm back strap 45 degree to help take the load at the top.
But I am only doing a one off for my own use (20 knucle nails in all), a 10 ton bottle jack is adequate for my purposes. This rig setup in the Video could be lightened by drilling holes in the base plate prior to fabrication. WE all get carried away with weight and the amount of weld. I hope that helps.
David Pullein, yes this helps a lot. Thank you for the information!
The first setup was not as stiff as this one. I added more metal to make it stiffer. it is stiffer, but much heavier and not optimal. Now that I have it, I will live with it.
Also, don't under estimate the capacity of a 12T jack to bend the rig. So, better to err on the heavy side if you want a straight press.
Looks good. Although I do have a dumb question. Why wouldn’t you put both plates in place to start with and then press them both at once? Seems to me like it would be half the work. Just curious. Thanks..
Much easier to have good alignment when pressing one plate at the time.
@@thewizard1446 you could have just as easily have tacked the top plate down first, then slid the other plate underneith and pressed it asll in one go.
Assuming you got those plates from a box store - read the fine print on the truss plates “not for trusses”.
yep, I know... The manufacturer wants to cover his butt as he assumes many people will hammer them. The only way to install them correctly is with a press. Not everyone has a press. So, the obvious warning is "not for trusses". Also, they come in just three sizes (1x4, 2x4 and 3x6), which is not enough. When you know what you are doing, and I mean "YOU REALLY KNOW WHAT YOU ARE DOING", they are a fantastic invention.
It looks good. I am a beginner. I would like to know the name of this weird metal accessories to bind the wood and where to buy them. Thanks.
Seems to be missing the engineering that determines the size and position of the connector plate? Did you just guess?
most plate are just centered on the joints, and that looks like a 2x4 plate so as long as theres half on the cord and half on the web it should be just fine.
That's a great many assumptions for just one video. For one assuming that that's necessary (it's not), and two assuming that he didn't. If he did the engineering math, why would he video himself doing the math? The video is about the press that he made. Ignorant.
There is a tremendous amount of calculations in truss design. Load or tension, plate size, type of plate, plate orientation, etc... truss design is done with special computer programs that have been developed over many years.
Man I hope you don’t throw your back!!
;) Still strong... and young.
I like the job you did but I would like to know a few things as I am looking at making my own for an off-the-grid house I want to build. First, are you using 2x6 for the top and bottom boards? Second, what dimensional lumber are you using for the cross members? And last, the width of the house is going to be about 38 feet and I want to have the front an open floor plan. Should I double up on my top and bottom boards so they overlap to span that length?
bottom cord: 2x6
top cords : 2x4
members: 2x3
I do not recommend using off-the-shelf mending plates. They do not come in the required sizes. The ones made specifically for trusses are the same gauge (#18), but in different sizes. Which changes totally their characteristics.
I built these trusses for a large shed.
How thick is the steel plate you used for building this press? Thanks.
See description.
Any idea where can buy truss plates not mending plates
how straigt does your top and bottom chords look?
Good for you on getting it done. Engineer?
Yep. Engineer
Do you have any plans for the frame of the press?
The press frame is a simple U. I welded it without any specific plan.
Where to get a neumatic pump press? I need one !
Princess Auto in Canada, Harbor Freight in the US, etc.
That’s what a hammer is for