Time for an overhaul of my 1.9 '98 BMW Z3 Individual

[Duncodin]

built up some weld that I could put a nut over it...

Are you sure that's in the right place? Are the threaded holes supposed to be equidistant from the bigger hole?

If the threaded holes are supposed to be evenly spaced from the bigger hole then it looks like you've welded and ground so often you've wandered a bit towards the centre? Dunno. Just looks that way to me

Put the handbrake wotsit back on and mark/punch it through the hole to make sure you're on the right spot

 

[Matt Barnes]

Are you sure that's in the right place? Are the threaded holes supposed to be equidistant from the bigger hole?

If the threaded holes are supposed to be evenly spaced from the bigger hole then it looks like you've welded and ground so often you've wandered a bit towards the centre? Dunno. Just looks that way to me

Put the handbrake wotsit back on and mark/punch it through the hole to make sure you're on the right spot

It's weird... it does look off doesn't it.... I was sure I welded over the "shadow" of the bolt but it looks way off in the photo... what I ended up doing was drilling a hole in the bolt with a carbide milling bit on my Dremel.. then filled that with weld, put a nut on it and filled it up..... and still no joy...

got a photo here of another attempt.... now that one IS in the right place !

 

[Duncodin]

I fear youve welded the thread up now. Only thing for it is to drill it right our and cut a new thread

 

[Matt Barnes]

I fear youve welded the thread up now. Only thing for it is to drill it right our and cut a new thread

you're probably right..if I'm going to have to drill it out then it's hub off..... dammit...

 

[Andyboy]

Well....

If you're doing a complete rebuild with new handbrake cables, that bracket never needs to come off again. So I'd bolt the bracket on with the single bolt and give the other side a small seam weld. It won't come off again unless you grind it off, sacrificing the bracket only.

 

[Matt Barnes]

Well....

If you're doing a complete rebuild with new handbrake cables, that bracket never needs to come off again. So I'd bolt the bracket on with the single bolt and give the other side a small seam weld. It won't come off again unless you grind it off, sacrificing the bracket only.

you know what Andy....I was only thinking of that option this morning...but it felt like a bodge...BUT...I'm at the point where I might just do that so I can crack on with the rest of the bits! cheers!

 

[Matt Barnes]

Well... I think I've come to the end of the road with this one... I don't have the welding chops yet to get this to work.... tried it on the other arm and got the same result....

Thought I'd have a better chance as there was a decent recess where the bolt snapped off

Got a good strong weld on there which actually forced me to use a longer spanner to try and turn it...

but again... no good.... tried 5 times with the same outcome....

I'm having real trouble with cobalt drill bits as they are literally not even scratching the surface... had to use a carbide milling bit to be able to remove any material

then tried East outs, 200mm long cobalt bits and nothing's touching it.....

So for now... I'm parking it.....leave the arms on the bench until I come up with a solution before I lose the will to live !

so next I think I'll paint the beam black, clean up the Diff and the Anti roll bar... then think about sorting the bodywork...

actually @Andyboy the decision has been made for me....because of my countless attempts of grinding off failed welding attempts, I've now taken off too much material so the bracket doesn't sit flush anymore.. ... so I'm either welding it on or I'm going to have to get another arm....

taken too much off with the Grinder.... b*gger....

 

[IainP]

I have a spare nearside I could Swap.
I’d take your Dremel and try and take the centre out of the bolt remains with a tungsten carbide.
Its only to locate the shoe, the centre spigot prevents it rotating, as suggested I would weld it if you can’t Dremel it out.

 

[t-tony]

How much bolt is actually left in the hole? You said 1 bolt came out, so if you put that bolt through the bracket it will show how much is left in the hole.

Tony.

 

[Matt Barnes]

How much bolt is actually left in the hole? You said 1 bolt came out, so if you put that bolt through the bracket it will show how much is left in the hole.

Tony.

in both cases it's the head that snapped off, so the entire bolt left in the hole...

 

[t-tony]

I thought I read that on each side one of the bolts came out and one didn't? Sorry if I misunderstood .

Tony.

 

[Matt Barnes]

I thought I read that on each side one of the bolts came out and one didn't? Sorry if I misunderstood .

Tony.

correct Tony...on both arms..one bolt came out, the other snapped..part of me is thinking now, you only need one bolt to secure the bracket, as it can't move anyway...

 

[Matt Barnes]

I have a spare nearside I could Swap.
I’d take your Dremel and try and take the centre out of the bolt remains with a tungsten carbide.
Its only to locate the shoe, the centre spigot prevents it rotating, as suggested I would weld it if you can’t Dremel it out.

thanks Iain...after beating myself up that I couldn't get the bolt out..it dawned on me that I don't need to..!...so what I might do is put the bracket on and if needed, weld a nut onto that...I've had plenty of practice !!

 

[Matt Barnes]

you can tell I'm on a week's Leave can't you

so with the Trailing Arm drama hopefully sorted... I thought I'd practice some vertical plug welding as I want to have a crack at the holes in the sill with this technique.... luckily I have a piece of 2mm plate that has a big hole in it !

started forming the weld around the outside

slowly working my way inwards... letting the previous welds cool a bit

Then fill her up !

after grinding down I did come across a couple of weak spots....

so plugged those up with the same technique....then ground it down... et voila !!

needs a bit more practice but I'm relatively comfortable trying this on the Sill at some point

 

[IainP]

Turn it up a little bit Matt, though that setting is probably perfect for the actual sill, the edges will be thinned.
Once you weld the initial ring, you can angle the torch slightly, and turn it up, then you get less holes.

 

[Matt Barnes]

Turn it up a little bit Matt, though that setting is probably perfect for the actual sill, the edges will be thinned.
Once you weld the initial ring, you can angle the torch slightly, and turn it up, then you get less holes.

Cheers Iain...after this I tried butt welding 1mm sheet and blew through all over the place so turned down the wire speed and voltage a bit... got some decent tack welds.....but for the sill itself.... I'll make a note... think I was on about 18v and 3m/min for that plug welding...

 

[IainP]

When you’re butt welding it depends whether you leave a gap or not. Loads of people say you should, then you get better penetration. Myself I don’t, I get the fit as tight as possible, but I’ve spent ages with bits of steel making sure the penetration is spot on. It’s just practice.
Both techniques work, just worth trying both to see what you’re most comfortable with and which you get best results with.
Also, be careful when grinding, I take the worst off with a 40 grit flap disc, or 75mm Roloc if you have a compressor.

 

[Matt Barnes]

When you’re butt welding it depends whether you leave a gap or not. Loads of people say you should, then you get better penetration. Myself I don’t, I get the fit as tight as possible, but I’ve spent ages with bits of steel making sure the penetration is spot on. It’s just practice.
Both techniques work, just worth trying both to see what you’re most comfortable with and which you get best results with.
Also, be careful when grinding, I take the worst off with a 40 grit flap disc, or 75mm Roloc if you have a compressor.

thanks mate.....all goes to building that experience..and no I don't have a compressor sadly

 

[Matt Barnes]

Took a break from welding, firstly to clear some stuff up and ditch some full garage rubbish bags....for today.... we paint !

rubbed down the subframe with panel wipe... or on my case.... meths ..the amount of crud that came off from all that welding dust

Then it was the first of a few coats of Hammerite Smooth

 

[Matt Barnes]

So today was another painting day.... laid down a good base of Hammerite Smooth Black.... I know it's nothing compared to powdercoating but it turned out ok.... subframe first....

oh that's not a crinkle in the pain on the arm.. it's the reflection of that plastic oil can

Then it was time for the offside Trailing Arm... just did the top and when that's dry I'll flip it over

Then it was time to treat and paint the nearside Trailing Arm.... I'd previously sprayed it with ACF-50 which is a corrosion inhibitor and I must say bare steel for nearly 3 weeks and not a sign of any flash rusting... good stuff...

so it wiped down liberally with Meths.. and dried... then a good coating of POR15 Rust Treatment... this is the dull zinc layer after drying with a hot air gun.

Then followed by a coat of Hammerite Red Oxide primer. Will probably give it another coat and then a top coat of Hammerite Smooth