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slim_boy_fat
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Excellent video [again]. 
cumbriasteve
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Good video and good castor loading explanation.
Just wondering why tig is your choice of welder, I imagine mig would be cheaper and faster on that type of work, am asking because my work has changed and tig may be something I am venturing into this year, just for mild steel.
My present local low price gas supplier is not so cheap with pure argon and unless I am mistaken tig eats the gas a lot faster than mig.
Just wondering why tig is your choice of welder, I imagine mig would be cheaper and faster on that type of work, am asking because my work has changed and tig may be something I am venturing into this year, just for mild steel.
My present local low price gas supplier is not so cheap with pure argon and unless I am mistaken tig eats the gas a lot faster than mig.
Thank you
You are absolutely right, a MIG would have been much faster and is a cheaper process in terms of time and gas usage. Sadly I sold my MIG many years ago to fund my TIG (one of my biggest regrets). Not getting the TIG, I love it but selling the MIG was a huge mistake. That said I would have probably still used the TIG for this project as I know i'm getting the penetration. Especially important with a project like this since it is very much structural! I would like another MIG but can not justify one at the moment. I can buy a lot of gas for the TIG with what I would cost to get a reasonable MIG setup.
Thanks again
lazybones51
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Good video, they are getting better each time. For the rotary converter video please go into as much detail as possible because I will be doing one soon as well
Thank you, I try to find something that I don't like / am not happy with in each video then work on improving it in the next one. My goal for the crane video was to improve the lighting. I think the welding table video was a bit dark in places.
Re; rotary converter. I ordered most of the bits today and checked the motor I have works; It does
. I have quite a lot of day job work to do in the coming weeks so it might be 3 weeks or so until the next video. Your request has been noted, I'l see about putting up the drawings on my blog or sharing them here in a post or something like.. Thanks
FergalFarty
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Can I ask why a rotary converter vs individual VFDs on each machine?
Sure,
The biggest driver for this decision is my lathe. It's a Harrison VS330TR which is direct on line start and has a lot of rotating inertia, therefore requires a lot of starting torque (starting current). It also has a 400v/600v motor rather than a 230v/415v. Therefore the cost of the VFD for this machine alone would be more than I think it is going to cost me to build a 4KW rotary converter. Also the lathe has infinite adjustable speed (between 0 and max of course haha) so I would not be using the main benefit of the VFD. (adjustable frequency)
With a rotary converter I can power all the 3 phase kit and any future kit that I may get from one box. The rotary converter also reduces complexity. The machine is expecting a 415v supply and all the ancillaries are pre wired with that in mind. I fell foul of this when my dad got a Bridgeport; We wired up the main motor to the VFD but all of the ancillaries are 110v on his machine (supplied via a 415v to 110v transformer) so things like the coolant pump and the power cross feed don't work and would need additional VFDs of there own, plus all the coils on the contractors were 415v. I'm sure you can see how the cost can spiral out of control when you have multiple machines.
So for my application it should work out significantly cheaper and less complex to have a rotary converter. Hope this answers your question and hope you enjoyed the video, you oviously watched to the end
Cheers.
eLuSiVeMiTe
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Another well made video.
Wish I had the room. Getting fed up of hand balling heavy machinery parts.
Using your drill press made me wince a bit.
Worth drilling a few holes in the mdf base to stick a few removable dowels in. Give you something to butt the workpiece against incase it snags.
Wish I had the room. Getting fed up of hand balling heavy machinery parts.
Using your drill press made me wince a bit.
Worth drilling a few holes in the mdf base to stick a few removable dowels in. Give you something to butt the workpiece against incase it snags.
steviec_lj
Rust Welding Professional
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Excellent video, as above though, using that pillar drill made me a bit squeamish.
I think you should sack off the day job until you’ve made the next video
I think you should sack off the day job until you’ve made the next video
Excellent video, as above though, using that pillar drill made me a bit squeamish.
I think you should sack off the day job until you’ve made the next video
Well you know...Safety first...
Find me half a million subscribers and i'l sack it off permanently
hahaCheers
Thank you, Short answer is that I did the maths.
Long answer... You need to decide you maximum design load (mine was 500kg) and its point of application (mine was mid span) on the beam and how it will be applied (mine was a point load). Then you need to consider the end effects; Is the beam a cantilever, fixed fixed or simply supported. From this you can work out your reaction forces. Then draw bending moment and shear force diagrams. That gives you the maximum bending moment and sheer force. From that you can work out maximum bending stress, sheer stress and deflection. Then you iterate the dimensions of your beam until you reach a size that gives you an acceptable safety factor (iirc mine is 1.5). You also need to look into Truss design and buckling for the A frames.
There are loads of beam calculation videos on YouTube, id start by searching something like "simply supported beam" then start adding key words such as "reactions" "point load" "UDL" "shear force bending moment", "method of joints" and "euler buckling load". That should get you started on the path to understanding the maths behind it.
I must add this point, apologies if it comes across as patronising that is not my intention. If you are in any doubt about what you are doing get a structural engineer to either do the calcs for you or check your work. Cranes are dangerous and a failure or over site during design is potentially life ending! The description above is meant to be an introductory guide not a definite list of 'if you do these steps it will be fine'.
Hope this helps.
Tilly
Carl Wilson
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So if you had half a million subscribers, you could stop work? Seriously?
