The V8 Owners Forum -

I'm planning on having a proper historic roll cage for the MG, welded in, probably the Custom Cages one in T45. It's probably one of the most expensive parts of the project, but I can save over a grand if I fit and weld it myself. What I want to know is how realistic is that for an amateur, has anyone else done it?

I have never welded before, but have a lot to do on the shell before I get to a stage where the cage can be fitted (will be later this year but I need to plan!). Hopefully by then I should be a half decent welder ...

Hi
Are you going to Gas, Mig or tig? I am pretty much self tought at welding (I did do a night school course for MIG about 9 years ago) but am entirly self tought at TIG. At TIG I consider myself up to this sort of task, I did some of the slingshot chassis cross members and all the brackets so I think with a lot of practice and some guidence you could easily do the same.
What I will say is that I find TIG much easier to use, vastly more contolable, you can control weld penetration very confidently, it is much easier to see what is going on and the end result is much neater (well it is for me) it is also much easier to weld metals of different thicknesses together with TIG. I find Mig Tends to be a bit more piont pull the trigger and hope. MIG tends to be more about the set up of the machine, Tig, with a foot pedel, you can adapt as you go.
One consideration is that TIG is not very easy to use while upside down (big understatment!), Mig is a little easier personally I would still use TIG but put the car on a rotisery if you do need to weld the underside of the cage.
Have you considered buying the FIA/ SFI specs and just doing the whole thing yourself http://www.sfifoundation.com/?
Best regards
Mike

Planning on buying something like a Clarke 150 for Gas Mig, because I (probably falsely) sasusmed Tig is harder (and more for alu type stuff etc).

Going on what you said, TIG sounds like the way to go. I assume I need a different type of welder, more expensive are they? Something like this ok? Looks gasless tho?

http://www.ebay.co.uk/itm/AC-DC-TIG-WEL ... 257c03634c

And yeah I have a rollover jig so don't have to weld upside down. I'm planning on stich welding the chassis and adding a couple of reinforcements to it (from the leading spring hangers to existing chassis rails, for example).

As for doing the whole cage myself from scratch, I'd need a pretty decent pipe bender as well!! Dunno about that lol!

Hi
That is the unit I started with, long story but I now have a newer version, they are pretty good for amature use, Chinese and they get slagged by "profesional" welders, but they do not cost £1500+ and need 3 phase power. They are not briliantly reliable, however the people who sold me mine honoured the gaurentee and just fixed the thing, including driving over a replacement unit on a Saturday and taking the broken one away, there are plenty of people who will fix them.
Tig will do body panels much better than Mig, it puts much less heat into the metal and distorts much less.
The pipe bender is an issue, and you need a "fish mouth" cutting tool for the ends of the pipe but again the extra effort is not huge.
Best regards
Mike

You have me thinking hard once again Mike!

Do those types of TIG require gas then?

As mike says, Tig is far better and actually easier than mig. If you get it slightly wrong you can go back over it like gas. With mig, the only thing you can do is heap more metal onto it - and then spend an hour grinding it all off again.
I dont think i've ever ground anything that i've tigged.

Aluminuim welding takes a bit of practice, but steel is dead easy and very forgiving.

Tig can weld anything, ally, steel, stainless, copper - for fun i tigged a piece of 15mm waterpipe using a bit of twin and earth as filler:



I hardly ever use mig unless i'm trying to knock something up that doesn't need to look pretty or be accurate.

Are you planning on racing this car?
If so will a self made cage be up to the specifications of the MSA regluations?

And are you going to use it on the road? If so you need to seriously consider the bar placements so as to avoid your bare head ever being able to hit the bar

My 2C worth - back to welding techniques!

Ian

Ian Anderson wrote:Are you planning on racing this car?
If so will a self made cage be up to the specifications of the MSA regluations?

And are you going to use it on the road? If so you need to seriously consider the bar placements so as to avoid your bare head ever being able to hit the bar

My 2C worth - back to welding techniques!

Ian

fast road mainly with some track.

Custom Cages supply a welding test kit with any self-weld roll cage, you weld the kit and send it back for strength testing, if it passes you get proper certification for the cage. If it doesn't then you pay them to weld it!

Not worried about bar positions really!

Have you priced getting a custom cage ( not the brand ) actually made and fitted to the car, by someone who can certify it if need be ?

Given what the guy charged me to make my cage and fit, I wouldnt even consider doing it myself.
And if the cage maker is any good, chances are it will be a much better fit than an off the shelf cage as they can take the time to make it a very tight fit.

As for the MIG/TIG debate...it is just that. MIG will be far faster and easier for cage building, although I'd say a small 150A machine might be pushed hard. I know my 140A Murex would be at it's limit.

TIG may have some benefits, but some people over exaggerate it's benefits, and for a regular steel cage I can see almost no benefit. If it's chromoly, then most will say you must TIG it.

Custom Cages prices for T45 FIA spec Historic cage:

£681 +VAT for just the cage

£1701 + VAT for cage + fitting

However, I want to add a second diagonal for the roof (to make a complete "X") and a second diagonal behind the seats (again, to make an "X"), as well as tie in the cage to the A-pillars. I also want to tie the cage into the rear chassis rails using two long sections from the main hoop, so there is definitely opportunity for me to go for a proper custom cage, however, I have absolutely no idea where to go or who to speak to about it? Can you advise?

*just trying to get hold of Nick @ Nickson Motorsport ...

I wouldn't say that TIG is easier than MIG, quite the opposite. However getting a perfect weld with either requires practice, and I wouldn't condone welding in a roll cage yourself unless you are a confident welder at best, you start with easy welds, then they get harder and harder as you are working upside-down back to front, trying to weld where you only have an inch or so gap between cage and panels etc.

Get a lot of practice in first, a badly welded cage is potentially worse in a crash than no cage, and no manufacturer will let you modify their cage even if it adding more tubes without their advice.

Make sure you know what you are dealing with with T45, you are supposed to use special rods/wire, and some people say it should be heat treated afterwards to stop it going brittle, though how much truth there is in it I don't know.

I've just spoke to Nick at Nickson Motorsport, apart from being a top straight up guy his advice was brilliant and the prices are bloody good! I found him through the Driftworks forum where he/Nickson is an official trader etc.

While I was on the phone to him, he had a look at the custom cages rollcage to see what it looked like, and we went from there. Basically, to have a cage how I want it (full "X" door bars, "X" in roof, "X" in rear, harness tube, A-pillar tie-ins, dash bar) plus additional braces to rear chassis rails in boot came in a fair bit cheaper! I then asked how much it would be to tie into the front chassis rails through the bulkhead ... still came out cheaper haha! It will be in CDS rather than T45, but I'll be happy with that.

So in short, I think I'm sorted.

topcatcustom wrote:I wouldn't say that TIG is easier than MIG, quite the opposite. However getting a perfect weld with either requires practice, and I wouldn't condone welding in a roll cage yourself unless you are a confident welder at best, you start with easy welds, then they get harder and harder as you are working upside-down back to front, trying to weld where you only have an inch or so gap between cage and panels etc.

Damn. I can't get on with MIG and thin stuff and hoped that just buying a TIG would be the answer.

chodjinn wrote:I've just spoke to Nick at Nickson Motorsport, apart from being a top straight up guy his advice was brilliant and the prices are bloody good! I found him through the Driftworks forum where he/Nickson is an official trader etc.

While I was on the phone to him, he had a look at the custom cages rollcage to see what it looked like, and we went from there. Basically, to have a cage how I want it (full "X" door bars, "X" in roof, "X" in rear, harness tube, A-pillar tie-ins, dash bar) plus additional braces to rear chassis rails in boot came in a fair bit cheaper! I then asked how much it would be to tie into the front chassis rails through the bulkhead ... still came out cheaper haha! It will be in CDS rather than T45, but I'll be happy with that.

So in short, I think I'm sorted.

Told ya so lol

X door bars are a pain in the hole for access though. I just did a low double bar, one horizontal and one diagnol so access is still pretty good.

Yeah I've been thinking about that Stevie, having a cill bar and single diagonal like the historic cages. I'd love to have nascar style side bars for a bit mroe room but they're a bit impractical with respect to the doors!