View Full Version : Toilet Reading...Metal finishing and files.
08-02-2004, 01:47 PM
I have a copy of one of Ron Fournier's books in my bathroom, along with a nice stack of other literature to occupy my mind whilst I rid myself of wastes.
Anyhow, I noticed Fournier uses files to do his metal finishing...as does Kent White. This struck me as a little odd being that I have been to Wray's shop many times and I have NEVER ONCE seen him use a file in his process of finishing a panel.
I know there are many ways to accomplish a given task...just wondering if anyone could shed some more light on this for me. Why preach the use of a file if it's unnecessary? Wray, why not use a file?
I know there is a fair amount of misinformation in this Fournier book...well maybe not misinformation, just a different school of practice. insight anyone?
08-02-2004, 05:43 PM
I have used files for some parts of metal finishing, mostly on aluminum. I have generally used them during the early stages when there is a lot of material to remove, say knocking down the top of an aluminum weld. For this task the benefit is fairly precise control over, the amount of and area from, the material being removed. The job could be done with abrasives or rotary tools, such as carbide burrs, and I have used them also.
I prefer the use of a file when time allows and I don't want to thin the material surrounding the weld. Abrasives tend to be good for blending. For material removal they can work well, but often you will wind up removing more material than you wanted and sometimes not the material you wanted. They can be the cause of heat build up and distortion when used improperly. The use of a file tends to be more deliberate and is less likely to be the cause of too much material removal or heat build up. Rotary tools offer many of the same advantages as files, but even in the most capable hands they can, and often do get away momentarily, causing some amount of damage resulting in additional work.
Some situations where a file would be benefitial are;
1 - When the fit up is very good and you want to take down the weld just to the point that it blends into the surrounding area. A file will not fix a poorly fitted joint.
2 - As a checking devise during finishing operations. A quick pass with a clean, sharp file will reveal low spots to be raised, or vise-versa.
3 - Working up to or around a detail where other methods offer less control.
4 - For knocking down tacks prior to welding. Again good control over material removal.
This is not a complete list by any means and I am sure others will have additional reasons why or why not.
I have rarely ever used a file exclusively for finishing. At some point and time I finish with abrasives. When I choose to use a file over another method it is generally because I have the most confidence with it for that particular task. It is just one group of tools out of many.
I have also learned, more recently, that many of the times in the past when I removed material I could have crushed the welds by plannishing and would have received better results.
08-02-2004, 06:23 PM
Hi Ken,There are two methods of using files in metal finishing a panel or seam. Some use a file to shave the surfaces of the panel down making the panel a lot thinner to make there work blend with the rest of the panel.
What Wray and myself try to teach is that you can work your repair seam or dents untill you have them close enough that you only remove the high spots of the weld and do not remove any of the actual thickness of the surounding panel to make everything blend in to a metalfinished joint. I myself do use files to highlight my repair areas by floating them across the area being worked to shine up the high spots and define the low spots on the panel. I use a variation of general purpose files and dull lead or vixen files for this purpose.I also use sanding blocks with 80 grit paper to highlight the area,usually the wore out paper from when the sanding block was last used.
Wray uses a variation of the sanding block to find his highs and lows and uses small sanding discs on his die grinder to remove high spots on his weld only and works the seam with hammers, slappers and hand and post dollys and his cp air hammer to metal finish his seam and dent work untill it is finished enough that it only needs a coat or two of primer to fill imperfections. We also both use the shrinking disc to finish the panel.
There are always going to be a lot of different methods of finishing a panel but if you are cutting surface metal very much you could be doing better by spending more time working the area with hand tools and removing good metal to make a repair look nice.
A lot of times we run into the problem of spending more time on a panel than it is worth or the customer has moneyn and then you would be better off to take the panel close enough for a skim coat of filler rather than thin the surface metal to make it look good. Dutch
08-02-2004, 08:02 PM
excellent information gentlemen. It's hard to argue against the results I see with Wray's work.
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