Cutting out rot in body panels - tool worth having???

[GRW]

In the "Forth Bridge painting" type of corrosion-chasing with my old camper - I have some patching to do.

One part is on the corner of the body by the rear doors, right up by the rainwater gully and where the glassfibre hitop join.

Using a 4" grinder to cut out there would be messy. I could drill/file/hacksaw a section out to replace yes... but thought I'd ask if there were any tools worth having to make the job easier/neater etc (without going nuts).

I've toyed with the idea of an electric nibbler (my 7cfm, 2hp 50L compressor doesn't have the spuds for air tools unfortunately) - but they can be pricey and not sure if that's the right way to go?

I'm a home tinkerer (& not an experienced one at that) not a pro or workshop - so i dont need Snap-On or daily hard use quality stuff, just useable.

TIA.
G.

 

[Ubique]

Plasma?

 

[GRW]

Plasma?

Never used one, but the workshop in work has a beast that slices through the steel on big digger buckets etc like wire through cheese.

Never thought of one tbh - I thought it'd be too aggressive (& likely to set fire to the van?) to use a Plasma Cutter?

 

[Maker]

Die grinder would probably be handy.

 

[mr haynes]

Hand nibbler/monodex cutter: draper ones are fine and cheap
Offset Aviation snips
Powerfile is just a handy tool period

 

[MCKDAVID]

Never used one, but the workshop in work has a beast that slices through the steel on big digger buckets etc like wire through cheese.

Never thought of one tbh - I thought it'd be too aggressive (& likely to set fire to the van?) to use a Plasma Cutter?

exactly, pretty bad idea, unless the shell was stripped, the sparks from the plasma would most likely set fire to something, even if it didn't you'd spend more time protecting it against fire that cutting out by other means.
What about a small recip saw, electric or air. This sort of thing. slow but easy to control

 

[123hotchef]

air body saw or recricating saw

 

[mr haynes]

Jigsaw with metal blade is essentially the same as airsaw if already have one

 

[Ubique]

exactly, pretty bad idea, unless the shell was stripped, the sparks from the plasma would most likely set fire to something, even if it didn't you'd spend more time protecting it against fire that cutting out by other means.

With a small (I assume small as it's for body panels, so <50A) plasma cutter, the protection / prevention wouldn't be any more onerous than for the welding operations themselves. Of course, if it's wound up to the max, then more strip-out & protection would be needed, but if set 'just high enough' it'd be as good way of cutting out awkward shapes without the mechanical stress. They're used a lot in automotive bodyshops. Welding blankets don't cost the earth either.

 

[MCKDAVID]

plasma puts out way more sparks than any body shell type welding process, and given it's for a roof type area, taking into acount gravity, those same sparks will be blasting out at around 5 bar all over the interior / trim etc. aye you could use plasma and fire blankets, but on a scale of the most suitable means of cutting out tools / application, it would be the last thing I'd use. You'd spend more time protecting everything against damage, you'd have already cut it out by cold means. For a floor pan down onto the ground or away from anything combustable why not, but for a roof above an interior, no way.

but each to their own

 

[GRW]

Die grinder would probably be handy.

I have an angled 1/4" die grinder. Nice tool but my compressor is too weedy for it - for very short bursts only or it's no use.
I did have a Dremel but 1. It's died, & 2. I always found one to be too gutless (maybe that's my fault).

A jigsaw I have - but with there being an inner skin on the corner - the blade is too long. Guessing a reciprocating saw would be the same - I'm also not very good with either in thin panels - find them a bit savage?

I might have to think about a die grinder then. I could use mini discs and use drill bits and then grinder bits to get into corners and file things etc. A reasonably pokey one would double as a drill as well in awkward places.

 

[Ubique]

I've seen plasma cutters used with surgical precision at the bodyshop we use, there certainly isn't a shower of sparks blasted out at five bar although all trim in the work area is removed / protected, which is what i'd expect whether it's a professional repair or a 'Sunday afternoon on the drive' type job.

 

[MCKDAVID]

I've seen plasma cutters used with surgical precision at the bodyshop we use, there certainly isn't a shower of sparks blasted out at five bar although all trim in the work area is removed / protected, which is what i'd expect whether it's a professional repair or a 'Sunday afternoon on the drive' type job.

which is precisely my point.. the time it's take to do all that, you could have had the job done with cold work. if the work required the removal of the interior, then maybe, but that's not really a small repair job is it.. plasma does have it's uses on cars, no doubt, but may not be the most practical for some tasks.

the 5 bar is relative to the air pressure on the plasma torch, don't know which ones you've used, but obviously the sparks will be sprayed out under pressure, inrespective of your surgical precision...

 

[GRW]

I've seen plasma cutters used with surgical precision at the bodyshop we use, there certainly isn't a shower of sparks blasted out at five bar although all trim in the work area is removed / protected, which is what i'd expect whether it's a professional repair or a 'Sunday afternoon on the drive' type job.

If my compressor is too weedy for a die grinder.... then wouldn't the same be true for feeding even a small plasma?
(At some point I'll have to beef up on the compressor anyway I suppose, but then I've the issue that the van is on the drive and a big comp is not so portable).

 

[Ubique]

which is precisely my point.. the time it's take to do all that, you could have had the job done with cold work. if the work required the removal of the interior, then maybe, but that's not really a small repair job is it.. plasma does have it's uses on cars, no doubt, but may not be the most practical for some tasks.

the 5 bar is relative to the air pressure on the plasma torch, don't know which ones you've used, but obviously the sparks will be sprayed out under pressure, inrespective of your surgical precision...

So start the cut from the inside? What I don't get is why people won't spend their own 'free' (as in, there is no cost to it) time doing jobs properly, in this case, stripping back and protecting the work area, but expect people that do it for a living to do everything 'by the book' when it costs them money? I wasn't using the plasma cutter in the bodyshop BTW, I'm not trained on their equipment so prohibited from using it (I can use whatever I want at home, however), I was there to isolate the battery in a BEV so they could remove it prior to carrying out body repairs - they didn't have anyone there with the appropriate training & certification to do my job either.

 

[Domdom]

If my compressor is too weedy for a die grinder.... then wouldn't the same be true for feeding even a small plasma?
(At some point I'll have to beef up on the compressor anyway I suppose, but then I've the issue that the van is on the drive and a big comp is not so portable).

No, I've run a plasma on a 24l 8CFM generic mini compressor. As long as it can deliver the pressure and you are reasonably patient it is fine.

 

[Ubique]

If my compressor is too weedy for a die grinder.... then wouldn't the same be true for feeding even a small plasma?
(At some point I'll have to beef up on the compressor anyway I suppose, but then I've the issue that the van is on the drive and a big comp is not so portable).

Don't know mate, check the requirements, although I think the cfm for a plasma is far less than air tools. there are some plasma's with built-in compressors and the case isn't huge so I would think your compressor would be fine - but as I said, check the requirements.
ETA
My plasma cutter (GYS Easycut 40) requires 115l/m which is a shade over 4cfm so you should be OK with your 7cfm compressor

 

[123hotchef]

You can get cordless die grinders too

 

[Maker]

I did have a Dremel but 1. It's died, & 2. I always found one to be too gutless (maybe that's my fault).

Give the Dremel to the misses to polish her nails and get a proper die grinder.

 

[MCKDAVID]

So start the cut from the inside? What I don't get is why people won't spend their own 'free' (as in, there is no cost to it) time doing jobs properly, in this case, stripping back and protecting the work area, but expect people that do it for a living to do everything 'by the book' when it costs them money? I wasn't using the plasma cutter in the bodyshop BTW, I'm not trained on their equipment so prohibited from using it (I can use whatever I want at home, however), I was there to isolate the battery in a BEV so they could remove it prior to carrying out body repairs - they didn't have anyone there with the appropriate training & certification to do my job either.

obviously you've missed the point completely, in simple terms there are appropriate tools for each job, a plasma torch is appropriate for some, but not all. Same as a sledge hammer will crack a walnut, it's unlikely going to be your first choice of method is it. Again it's not a question of avoiding spending time to do the job properly, I consider doing that job properly means using the most appropriate tool for the task in hand, preferring to avoid uneccessary work when I can use other tools which involves less clean up / less fire risk, but heyho somefolk will always find the hard way, rather than the easy option, if they want to make life difficult for themselves, that's their choice.