New to welding 7

[yaston4]

Hello all,

I am a mechanical engineer by profession, I am planning a kit car building projech which will involved welding to learn and improve my skills. I would like to carry out the welding myself and therefore will need to learn as much as I can, does anyone have any experience with welding for automotive, what type of welding is best and suggestions/advice for me.

Thanks

 

[geesamand]

Start with a welding class or few. Local technical colleges and Vocational Technical schools are great options in my area.

David

 

[kingnero]

Take up stick, MIG/MAG and GTAW demo classes. you will soon get a feel of what is more practical in each instance, as they all have their advantages and disadvantages.
Building a cage where the welds will be showing? GTAW. Bodyshop work? MIG. Making all kinds of brackets without the hassle of bottles of shielding gases? Stick.
There are some great instructional videas on youtube, but you will need lots of practice.

 

[Tmoose]

I would not be without An Oxy Acetylene kit. It has multiple uses.

 

[bigTomHanks]

I recently taught myself to weld at home using internet videos and a lot of practice. After watching a few videos I got some scrap and went at it with my cheapy MIG welder in my garage. MIG welding is about selecting the correct wire speed and power setting to ensure that you are laying down a weld that penetrates the surrounding metal and fills the weld cavity without globbing on the the wire. I would start with a low power setting and low wire feed and gradually increase both as need to get a weld that both penetrates the surrounding metal and lays down just enough metal to fill the seam. Your welder will "talk" to you and as you get more experience you will be able to make adjustments according to what it is doing.

Some basics:

If you burn though the power is too high or the speed at which you weld it too slow.

If your arc is not consistent or intermittent your wire feed rate is too low.

If you are globing on the wire then your wire feed rate is too fast or you are welding too slow.

If your weld is not penetrating then your power setting is too low or your feed rate is too fast.

 

[bigTomHanks]

http://manuals.harborfreight.com/manuals/68000-68999/68887.pdf

When you do start welding just take a go at several pieces. Then look at pages 19-21 from the link above and match your welds. Then make adjustments per the guidance given.

 

[yaston4]

Thank-you all, definitely at this stage my priority is easy and low cost rather than quality of finish. After looking at a few places on the net, it seems that no gas MIG is the way to go to start with. My aim to learn the process and use it mainly for car chassis welds plate welds, hole filling. Mainly internal stuff, so appearance is secondary to weld integrity and strength.

Thanks again everyone.

 

[yaston4]

Also, all the welding will be done in doors in a garage. Really looking forward to learning and improving my welding skills. It will hopefully improve me as an engineer also, appreciate the complexities and challenges of welding.

 

[berkshire]

If you are going to use no gas mig ( Flux core) in a garage, you had better have the door open or a ventilation fan running, or in 5 minutes you are not going to see across that garage.
B.E.

 

[kingnero]

Good luck using FCAW on thin plate, I'd recommend you do a bit more research...

 

[yaston4]

I have found this to be a really useful resource

http://www.mig-welding.co.uk/

 

[chicopee]

For body work, brazing is one process to learn.

 

[RossABQ]

First, a road-going car chassis is no place to questionable welds. By all means get training with destructive testing of welds.

Second, MIG, stick or flux core, you need good ventilation. There are elements in MIG wire that cause brain/nervous system damage if inhaled in quantity. (Molybdenum?)

 

[yaston4]

Thanks RossABQ,

Yes, after a lot more research, I can see that some areas of welding are just best left to experts and good equipment. I have decided to go for this to be a hobby and improvement of my engineering knowledge and skills rather than for important and safety critical welding.

In terms of the safety advice, thank-you.

 

[yaston4]

chicopee, I noticed than you can buy a separate attachment for an arc welding to make it suitable for brazing, not sure how well these work though.

 

[Tmoose]

"separate attachment for an arc welding "

Are you referring to a carbon arc torch?

http://www.tractorbynet.com/forums/...8-plasma-cutters-finicky-twin-carbon-arc.jpeg

 

[RossABQ]

Brazing is not typically used for bodywork. When doing a restoration, finding brazed metal is worse than finding bondo. MIG or TIG welded replacement metal is the proper repair.

 

[ledon]

Gas shielded MIG and TIG processes are the best for most automotive work. Stick is hard to control and nearly impossible on thin sheet-metal. Gas-less Flux-core is too hot and causes a lot of warpage. MIG with an argon gas shield (argon provides the best cooling effect) will provide a denser weld with less heat and less warpage on your thinner materials if you use a stitch weld and back step technique. TIG is good for thicker materials like your brackets motor mounts, etc. Both will take a lot of practice especially on thin materials.

 

[chicopee]

I used bondo to fill areas that were clean out of rust. I brazed sheet metal to sections of car bodies such as quarter panels that were cut out but then you have to smooth out all the brazed joints with a little bondo.

 

[ledon]

Brazing is not a good option for many reasons. The reason stated by RossABQ is chief among them. Gas welding is often used, (same process, different filler metal) but warpage due to heat control is an issue.
The use of bondo is fine, but if the kit car is metal then I would suggest lead filler instead. It bonds better and is not subject to fatigue cracking the way most bondo's are. I am restoring a 67 Fairlane. I intend on going back in with the original lead filler, as used by Ford, for authenticity and durability.