Thread: Chris's 2nd Build "Big K4huna"

Originally Posted by Gar

Its great to see these creations coming together, I'm looking to put a machine together myself but I'm only on the first few steps.

I think CAD designing is a very good idea

Thou I wish steel was as perfect as my drawings. I calculate measurements and I find I loose a millimeter here and there due to imperfections in the steel, or welding , just getting the diagonals right was a pain in the ????, next time I think I will pay the steel mob to weld up the base, as the first one they did for me it was a good job, just not sure what they will charge.

Its slightly a different base from the one I drew up but the Gantry is still up in the air.





What I did today.

lifted and flipped the table, me, my brother, and my dad were needed to flip it, I recon its around the 120-150Kg mark now. I will be making some supports so the forklift can move it.

Overloaded my little MIG twice today must be the heat, as its normally fine on long runs, then again its running on max power output.

Loaded my 3rd spool of wire onto the mig (running at 10m/min the .8KG spools dont last long, just running .6mm ATM)

Tacked the feet, tommorow I will be putting the braces between the legs (I think thats what you call them?)

Got burnt like 10 times when tacking as I was too lazy to gear up + the gush of wind didnt help

I love seeing pictures of other builds so here are some pics of mine.

It will have a low table in order to hold alot of MDF if I can get a discount for buying in bulk

As you can see the welds look ???? but are alot better than when I started, I will have to go over the top and redo them.

BTW for the ???? welds I tried to find the worst, so dont worry the whole table is not covered with these

Hi Chris,
Coming along really good there. Now I understand why you needed help to flip it over.
Yes keep the pictures coming as I am very interested in your build.
Surely one of those shovels can push a few sheets on your table when you are done.

Is your mig running at max capacity, the welds are not hot enough and your not getting penetration, last ones a bit better but sameproblem on the ends.

Either amp it up more or slow your feed speed right down.

Overall construction hoewever is looking pretty good. Will be a good unit when its finished

Originally Posted by simso

Is your mig running at max capacity, the welds are not hot enough and your not getting penetration, last ones a bit better but sameproblem on the ends.

Either amp it up more or slow your feed speed right down.

Overall construction hoewever is looking pretty good. Will be a good unit when its finished

No, I think its more of my ???? job, the welds are penetrating, the steel I can actually see melting when I do one of the corners. I have to do a wide pass otherwise the steel just melts away.

I have tons of welds on the top which just havnt penetrated. (well they have but they are more like a bead. (too low amps) Just saying I know a ???? weld now


Amps are up to max and is about 6-7 meters now as I am working with .8mm. Was up to ~10m min with the .6 wire.


I have a CIG Transmig 135.

http://cgi.ebay.com.au/BRAND-NEW-CIG...1%7C240%3A1318


Specs are there, I am welding 3mm Box and 4mm RHS


I'll take more pictures of the welds tommorow.

Yeh the 135 is a small unit but will do the job. Try and bevel the ends a bit by thinning the metal down a fraction, it will allow the weld to penetrate a bit better,,,, and slow it down.

Easiest way to assess a weld at a glance is if it has a buildup on the surface then it has next to no penetration. A hit with a hammer will seperate the job easily. A good solid weld will be almost flat this means the filler material has flowed in and bonded. The haz zone on your last weld shows that your getting there.

When welding a cornered section of rhs with a butt end, start the weld on the solid corner and then when you can see it glowing red bridge it across to the butt end. Bias your weld run more to the corner edge than through the centre. Otherwise you will start melting the exposed edges away

Practice makes perfect

Originally Posted by simso

Yeh the 135 is a small unit but will do the job. Try and bevel the ends a bit by thinning the metal down a fraction, it will allow the weld to penetrate a bit better,,,, and slow it down.

Easiest way to assess a weld at a glance is if it has a buildup on the surface then it has next to no penetration. A hit with a hammer will seperate the job easily. A good solid weld will be almost flat this means the filler material has flowed in and bonded. The haz zone on your last weld shows that your getting there.

When welding a cornered section of rhs with a butt end, start the weld on the solid corner and then when you can see it glowing red bridge it across to the butt end. Bias your weld run more to the corner edge than through the centre. Otherwise you will start melting the exposed edges away

Practice makes perfect

Ahh now I know what you mean.

Will turn the wire speed down and see what it produces, Maby I just have the perfect weld confused


I'll have more pics tommorow.

Its all a learning curve, PS I inspect welds for a living. Ive seen welds that are laid as flat as the metal they are on. To the point I think they've hit the surface with a grinder and then polished it afterwards, but they havent. Your better to go to hot than to cold. When its to hot you will see a very fine crater around the weld where its actually undercut the parent metal itself. The trick, like I said, is to bias your run on the corner of the closed edge than the exposed edge, this allows you to maximise your heat and minimise melting the metal

My welds are not perfect either, I tend to leave a slight crater running up each side of the weld from running too hot.

Originally Posted by simso

Its all a learning curve, PS I inspect welds for a living. Ive seen welds that are laid as flat as the metal they are on. To the point I think they've hit the surface with a grinder and then polished it afterwards, but they havent. Your better to go to hot than to cold. When its to hot you will see a very fine crater around the weld where its actually undercut the parent metal itself. The trick, like I said, is to bias your run on the corner of the closed edge than the exposed edge, this allows you to maximise your heat and minimise melting the metal

My welds are not perfect either, I tend to leave a slight crater running up each side of the weld from running too hot.

Yea a few have the crater, They required that I do a wide pass, but still ended up concave.

I dont plan on grinding most of them down. (Only the visual ones like on the top ect) I will take a picture of a ???? weld on the top when I reflip it over, I have a few extra supports to add to the bottom.

More Pics, Turned the speed down about 2-3 meters and it just blew holes like crazy, see the last picture for my welding repairs (Just add more weld)

First picture is my perfect weld It was the 2nd weld done after I increased the speed about a meter (after decreasing it 2-3 meters) 2nd shot is the side view.

Added some diagonal leg supports also.

Was going to use the 125x75 as fork slots but I found out the fork is 13cm wide So I might just not worry about it now, If I need to move it I can put the forks underneath it and strap them to the bench.

Got all the welding done, just waiting till monday so I can get more steel.

Going to weld plates to the feet, with a hole in it if I ever need to bolt it down.



Was hoping to see a reply from you simso about the welds

Originally Posted by Ch4iS

Was hoping to see a reply from you simso about the welds

Well there getting better, there more than adequate for what your purpose is. practice makes perfect.

As your starting to realise when the unit is at max amperage a lot comes into wire feed and hand speed, when you have the capability to run mega amps then you can be a lot more blazzay about it.

Keep the pics coming. Looks like it will be a fairly beefy unit when its finished.

After moving it to the ground I noticed a few problems with the welds pulling and a few errors on my part.

The longer diagonal pieces pulled the main beams into like a bow, so I've got that fixed, I removed the longer diagonal pieces and I will use the bottom section to straighten out the beams again, I could have left them but just decided to remove them.

Another problem is due to the perfect starting ground (uneven flooring). When I moved the horses (are they spelt like this) I forgot to make sure I was working on level ground as before I used aluminium as a shim to fix the uneven ground. This is a major problem as everything has been basically welded up, gota use my dads ram to bend the steel.

I guess its something to remember next time.

I thought I took more pictures but I guess not, didnt get a before shot before I removed the diagonals which it looked good but with the level it was bowing.



BTW Rod the offer was rejected

Hey mate its getting there.

Uneven surfaces are a no no for jigging.

Whilst not trying to tell you how to suck eggs etc, My way is I set up two horses and then drop two steel rails on the horses, I get these rails nice and level and clamp them down so they cant move, this creates a solid building base. Then build on top of them.

The first thing to build is always the table top and then you build the legs etc from there. When you do the table top just tack the ends on and into place on one side only, tack weld one rail down onto the base bed, then using a tape measure measure across the diagnols align them with the movement of the free rail with a hammer until there even and then clamp it down and weld it up.

It will give you a perfectly square base