Reliable method to meaure metal thickness

[thepurpleblob]

Sorry - newbie question.

I need to replace some rusted metal on an inner wing. What's the best way to establish the correct thickness? At the moment it's a combination of rust and underseal at the edge I can get at and all I have is a digital caliper (no use).

Ta!

 

[madkayaker]

Is there a forum for the car your restoring as they will know

 

[brightspark]

Sorry - newbie question.

I need to replace some rusted metal on an inner wing. What's the best way to establish the correct thickness? At the moment it's a combination of rust and underseal at the edge I can get at and all I have is a digital caliper (no use).

Ta!

cut back the rusted metal away and measure with the digi

 

[thepurpleblob]

brightspark - yeh, that's so obvious it hurts!! In my defence, I was reluctant to start cutting away until I had everything to hand but I probably don't have a choice.

madkayaker - good point and there is, but they won't. It's a BMW 840!!

 

[wheresmejumper]

an outside caliper?

 

[wheresmejumper]

 

[thepurpleblob]

Ok, thanks everybody. I was just checking that there isn't some devious method for establishing metal thickness - but it appears to be "measure it"

 

[the snooper]

measure the edge of the wing under the bonnet there is usually a lip there

 

[FranV8]

Ultrasonic thickness tester. But they're not cheap. Unless you know someone you can borrow one off.

 

[madkayaker]

You can measure with ultrasonics but the cost of the kit will be high I would think.

 

[the snooper]

Ultrasonic thickness tester. But they're not cheap. Unless you know someone you can borrow one off.

You can measure with ultrasonics but the cost of the kit will be high I would think.

echo echo echo

 

[thepurpleblob]

I've got a plastic school ruler somewhere - I'll be fine

 

[brightspark]

lol ultrasonics on a car body christ what next a bit ott

 

[Robotstar5]

lol ultrasonics on a car body christ what next a bit ott

A Faro arm if you can reach both sides

 

[the snooper]

A Faro arm if you can reach both sides

come on he doesnt want anything that cheap

 

[thepurpleblob]

I'm learning stuff - I didn't know what a Faro arm was two minutes ago. Now I know that I didn't need to know

 

[FranV8]

mk - I guess you haven't seen the small handheld units. we have a couple at work, and they're used to tell pipe work and tank thicknesses. it'd happily do bodywork. but it wouldn't be worth purchasing yourself.

If you've got any friends or contacts in a processing business , they may be able to o a quick check with one for you. it just needs a cleaned back bit of metal, you switch it on, put the probe onto the bodywork and it gives you a reading. Simples.

 

[Paul G]

I'd use a pistol drill with a 3mm drill in it.

Drill a test hole in a bit of scrap of a known thickness and note how long it took to drill through.
Drill the suspect panel, and if a blip on the trigger is all it takes then it needs replacing.
You will be able to see the edge of the hole anyway.

Paul G

 

[Sean]

bloody 'ell talk about sledge hammers and nuts

somewhere there will be a panel edge - look at it and choose a bit metal that looks the same surprising how accurate your eye is, then put it edge to edge with the new bit and feel the difference

its probably going to be <1mm,>0,6mm 0.8mm is a good average even if your out by 0.02mm its still going to be stronger and better looking than flaky rust holes

 

[pedrobedro]

Just get some 18g and weld it in and don't worry about how thick/thin the original was. It will vary in places where it was pressed. I can't believe the suggestions so far, do they allow for the extra thickness of the paint and underseal ?