Hey,
Im about to purchase a mig welder. Im still new to welding although ive done a bit of it at work now and i done a week course on it for trade school (im an apprentice motor mechanic). Im contemplating enrolling into an after hours panel beating specialist course to get a few extra tips. I honestly think all the help i need could be sourced online though. So i am dedicated and determined to shave my bay. Im looking forward to getting stuck into it but i need some help along the way as im completely new to it all. Im sure this thread will help others too. Ive tried searching and havent found many tips on the welding/grinding side of this job.. its all wire tuck info.

Im just wondering if anyone has any tips on shaving an engine bay as thats why im purchasing a mig welder. Ill shoot a few questions that im wondering and id appreciate it if people could post some other hints and tips other than what i ask. Even some helpful links.

1. Where the seam sealer is, is the best way to do this to remove the sealer and then weld where the sealer used to be then grind it all back smooth?

2. With welding holes, how do i weld up these. Can someone give me some advice on how to weld the small holes, and some advice on how to weld the larger holes. Did you use sheetmetal?

3. Also, any tips on grinding?? any do's and dont's? What grinder and discs did you use?

Thanks so much for any help, it will all be incredibly useful to me. Wish me luck with this project. I certainly will need it but at least im gonna give it a shot i guess.

 

having done a few like you're talking about doing....
Go to http://www.harborfreight.com and buy a 4" angle grinder, a 4" knotted wire wheel, extra discs, and maybe a pack of flapper wheels for it. This will make your life SOOOOO much easier. I've done it with die grinders, cut off wheels, etc, and it just took too damn long. The 4" grinder is the way to go.
Also, that grinder is on sale right now... I know cause I just bought a second one (don't have to swap wheels all the time). And if you buy two, buy the service plan on one, cause it doesn't mention serial number... wink wink...

For filling smaller holes, if you can get behind them, use a copper or aluminum shunk behind the hole, since the weld won't penetrate those, and it will help control the weld. Just use some small tack welds until it is filled in. Then grind it smooth. Heat control is key, since it's easy to eat away at the metal if you're running it too hot.
For the bigger holes, get some 16 or 18g sheet metal. Make a template with cardboard. Another great tool from Harbor Freight is the electric sheet metal nibbler. I was skeptical, but bought it anyway, and it works great. Also, get a pair of tin snips for cutting smaller pieces. Cut your pieces out. Use magnets to hold them in place, and weld em up. This will challenge a new welder. It takes some time to get the hang of it. Make sure you're moving around on the piece so you're not heating things up too much.

Definitely practice before you start on the car. Make sure you know you can weld sheet metal... It's a way different world than just doing some basic exhaust work. Although, it sounds like you may have more experience than that...

Aside from that, just plan out what you want to clean up. Tackle one task at a time. Don't jump from one end of the engine bay to the other. Once one area looks like it's ready for primer, move to the next area.

You may also want to check around on some VW sites. Those guys are notorious for doing this. They could probably give you some good info.

 

Thanks heaps Bakeoff, appreciate the help heaps.
Helps alot. I might check out some VW sites when i get the chance too.

So for welding a large firewall hole.. would you use the sheetmetal on the inside or outside of the firewall?

I would have thought just tack welding the small holes up that when you grind it back it may just bring the hole back. I guess theres one way for me to find out

And one other thing, how perfect do you have to get the the grinding. Does it have to be super clean. I notice people use metal glaze or something?? Is this process used to tidy it all up?

 

Inside or out doesn't really matter. I have gone outside where it is dimpled back, so the recess is more shallow. Or you can do it so it is totally flush...
The grinding really depends. You can get it pretty damn nice with the flapper wheel. Using that, you should be able to get it almost smooth enough that just some sandable primer would take care of it. Otherwise, you can use some body filler, depending on location. The shock towers are notorious for flexing, so I wouldn't recommend it there.

 

Thanks again. I think i got enough info to get started now! Havent used the flapper wheel on an angle grinder before. Obviously not as harsh as the discs.

No doubt ill bump this thread up when i get started on this and get stuck somewhere

 

I forgot to mention, the wire wheel will be VERY handy for cleaning off the paint, seam sealer, etc. If you're going to lay a good bead, it's a must have. Also, on the firewall stuff, make sure you take out your dash so you can remove the sound deadener pad in there. Wouldn't want that catching fire.

 

Thanks. Yeah my car is pretty much a bare shell..

Also gotta throw a cover over the windshield. Will mess the glass up otherwise.

Something for anyone reading the thread as advice to note

Can you remove all the seam sealer and weld everything up?? or are there certain areas you should leave the seam sealer in place?

 

Heres the MIG i'll most likely be purchasing in a week or so.

http://www.justtools.com.au/prod3488.htm

 

holy **** why are you spending that much on that thing?^ get somthing cheaper my god.

 

if your looking for tips on shaveing your bay why dont you just go to the shaved tucked and engine thread theres over 200 pages and mostly all the info is in one big section on the 1st page so its easy to find and if you go through the whole thread you will find alot of info as well much easy then asking qurestion and even if you have more they are prob already asked there and you also have alot of people who would know if there werent so good luck man

 

It is in AUD not USD.
Ive been looking around. I'm splitting the cost of it in half with my dad as he needs to do some welding also.

I would think any less than the 200 would be pretty weak, we may need the welder for thicker steel etc... Im not really experienced with welders so im not too sure. I'm just going by what ive been told. All the welders of this level seem to be around that price. Ive checked out a few places.

I still have a little shopping around to do before purchasing one yet though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C1EM1 &raquo;</TD></TR><TR><TD CLASS="quote">if your looking for tips on shaveing your bay why dont you just go to the shaved tucked and engine thread theres over 200 pages and mostly all the info is in one big section on the 1st page so its easy to find and if you go through the whole thread you will find alot of info as well much easy then asking qurestion and even if you have more they are prob already asked there and you also have alot of people who would know if there werent so good luck man</TD></TR></TABLE>

ive been looking through that thread. Takes quiet a while to read through so many pages, and yes there is plenty of info which im taking in as much of it as possible. I havent come across much yet on welding/grinding techniques in it though but i must admit im still going through it.

I dont see a problem with creating a thread to get some info just on the welding/grinding side of things. Dont have to sort through 200+ pages of tuck info and everything else. Im sure in the welding/fab forum theres some realy useful guys with some great tips.

 

well as far as the welding and grinding goes its pretty simple mostly everyone does it the same way....for the smaller holes you can fill them by welding them shut and same goes for some of the bigger ones for the ones that are to big you can use a peice of sheetmetal to close it off...and as far as the grinding goes there just grinding it smooth and if theres any holes when your done grinding just weld over it again to close the hole.... as far as tools go i used a 4in angle die grinder and a mini angle die grinder and most people are useing the same tools so good luck....i dont care if you start another thread ask all the questions you want