Welding Tips and Tricks

Hello, I am new to the forum here. I don't know much about welding and as you will see, my english is very bad.

I am restoring my old car and I would like to weld my rear bumper directly to the shocks absorbers. Everything is now ready but I have a question just before that I push the trigger.

My bumper is chrome platted on the outside, do you thing that the chrome could be affected by a weld made on the inside?

Thanks for your help and advices

welcome to the forum.

Ventura76 wrote:Hello, I am new to the forum here. I don't know much about welding and as you will see, my english is very bad.

I am restoring my old car and I would like to weld my rear bumper directly to the shocks absorbers. Everything is now ready but I have a question just before that I push the trigger.

My bumper is chrome platted on the outside, do you thing that the chrome could be affected by a weld made on the inside?

Thanks for your help and advices

Ventura, Welcome aboard.

The chrome on the outside is very likely to be discolored by the heat caused by the weld on the inside. The discoloration may polish out, but there may be metal distortion also (burn through). How thick is the material that the bumper is made from?

Also, as it's not technically easy to chrome plate on one side only, it is likely to be chrome-plated on the inside also, so you should clean and grind that section back to parent metal first, before welding.

Incidentally, your comment: "I would like to weld my rear bumper directly to the shocks absorbers"
That seems an unusual practice!
Is that manufacturer's design standard, or a Ventura modification?

Cheers

Ranger

I will add that the "shock absorbers" , if they are the ones I'm thinking about, have the opportunity to explode if overheated. Be careful and would recommend you search for other options before going with your current plan.

Hi and welcome
What nationality are you?

You have to be really careful about heat input. Old chrome plated parts have a copper layer between the steel and plating so over heating it can cause the plating to blister or peel off.

I have welded chrome plated parts with success but with tig and 316 filler. Just short strings and then immediately cooled with compressed air. The discoloration polished off.

Get some plated scrap material to practise on before you fire off on the old part.

Regarding comments on the shock absorbers, I'm pretty sure its a language confusion.
When not having english as first language some words dont translate well.
In my language the words for bumper would translate to shock absorber

Old VW Beetles had a shock absorber behind the bumper, maybe others do too.

Len

Hi guys and thanks for your answers and advices. I am French nationality but living in Canada (Quebec City).

For the question: Is that manufacturer's design standard, or a Ventura modification?

It's completely not a manufacturer's design standard , the bumper and its mounting bar were completely rusted. I found a 'new' bumper but cannot find the mounting bar to fix the thing on the absorber. That's where I had the idea to weld it.... but after all your comments and specially the one of dsmabe I will probably consider others options. Maybe make my own mounting bar.

You will find here pictures of the 'shock absorber' and No.... It's not a bra
Thanks. I will probably have a lot of other questions while making my mounting bar

I didn't want to scare you, and most likely the heat from welding wouldn't cause the shock to fail. Most of the bumper shocks are designed to relieve pressure when overheated, and they are normally pressurized. But there is the slight chance that the shock would fail during welding, and that danger is what I wanted to make you aware of.

Thanks dsmabe

I didn't feel comfortable with my welding idea. Your warning was just a reminder for me. I have to find a way to buil my own mounting bar and start to weld something easier.

Thank you

Post pics of the actual parts and how you want to attach them you will probably get better suggestions on how best to make the repair

Heres how you weld those bumper struts. 1drill a 1/8 inch hole in the strut body near the back wear eye/face protection it helps to drill thru a shop rag. When the drillbit pops thru it will spray the hydraulic oil inside out so keep your head back once the fluids out you can weld right around it. Ive done many bumper struts over the years, I did autobody 25+ years and we did this with many different models because they then made great holds to attach chains or clamps when pulling frames. And if you do heat them to much they will blow in one of two ways and you never know which way. Way #1 the whole unheld, unclamped section will literally go flying across the garage. way #2 the seal in the middle will pop spraying hot oil all over everything. Ohh and when one does "explode" it sounds about like a shotgun blast.
Good luck and stay safe.

I have to add to 5DIMES' comment... Defeating the hydraulic shock also defeats the DOT mandated 5 MPH bumper impact apsorption.

Will anyone in authority ever notice? Not likely. Unless you are rear-ended by a Mercedes, and you try to sue for your whiplash... Expect a thourough investigation then.

(My job requires an above-average awareness of DOT vehicle requirements.)

Steve S

Otto Nobedder wrote:I have to add to 5DIMES' comment... Defeating the hydraulic shock also defeats the DOT mandated 5 MPH bumper impact apsorption.

Will anyone in authority ever notice? Not likely. Unless you are rear-ended by a Mercedes, and you try to sue for your whiplash... Expect a thourough investigation then.

(My job requires an above-average awareness of DOT vehicle requirements.)

Steve S

I should add Im not advocating to weld them and using them on the vehicle. Like I said we used old ones that we welded up strictly for straightening frames on wrecks. I was just explaining how to weld the bumper struts so they wouldn't "explode" and cause injury or damage.

Just a example of what can happen if a bumper shock explodes.
[youtube] Exploding Bumper Shock Absorber Injures Firefight…: http://youtu.be/Klr0xUif8UA [/youtube]