Hi guys, normally I'd post this in the lounge but I guess it really should go into the body and exterior forum. I started sanding on the old 38 DeSoto awhile back (after primering) I applied some tiger hair type stuff to fill in the smaller dents etc. After wet sanding the filler it seemed to take forever and the paper would tear after a short while. I should have used more aggressive paper but was using what I had availible. Anyways sanding is a total bore to me so I have put off this part of the build as much as possible. One day I was looking through the auto section while waiting for my wife at Wally World and found this sanpaper that claims to last three times as long and dosen't hardly clog. I thought what the heck the price is reasonable so I bought it. I finally forced myself to go out and bore myself with some more sanding and to my surprise I've sanded with this paper for an hour and it still seemed in relatively good usable shape and I used no water. After boring myself with this sanding job I was relatively impressed with the product so I thought why not speed this up and use my palm sander. WOW! It sanded the area in just a few miuntes. I like this stuff. If it warms up outside again I might get enough (I have lots of sanding to do) ambition to get it all sanded and ready for paint by this winter. Here's a pic. The left side is after sanding with the course grit. I haven't got to the finer grits yet and the right side is what it looked like before I started sanding. Maybe a lot of you guys already use this stuff but it's my tip of the day if you haven't tried it yet. Sure seems to make a boring job go much better and faster. (faster that's the thing for me :thumbup: ) It's 3M sandblaster sand paper.
I could hardly get past the part where you wrote that you are using Tiger Hair for small dents. That's some serious punishment you are giving yourself, 38 special! When I have to use Tiger Hair, I sand it with... a grinder! Seriously, you might as well trowel on some concrete! Tiger Hair has its place, for me it's used mostly in fiberglass repair. If you have worked those dents out as well as you can, there is no reason not to use a high quality plastic filler like one of Evercoat's Rage series that will last for many, many years and save you lots and lots of elbow grease!
Yea I am with crashtech. No wonder you hate sanding.
Get some decent filler and you will find it easy.
Besides its about impossible to handsand tigerhair to a decent "flat" finish by hand. you can get it smooth but unless you are using really coarse paper it wont be flat.
i also tried that sand paper and i also love it, its really amazing (well not that exciting, hell its sandpaper :D ) but it truly works well
“Basics of bondo types”
"Regular" polyester body filler, and polyester "putty" is basically the same thing. They are both, you guessed it "Polyester" based. Polyester is what fiberglass is made of. The fillers have talc and some other components that give it "body", that is the basic difference between fiberglass resin and polyester body fillers.
The Putties have a finer ground talc than "regular" filler. They cost MUCH more, but are well worth it for skim coats and minor repairs. Being they are polyester they use a hardener and CURE like fiberglass.
The old "spot putties" DO NOT use a hardener and are simply lacquer primer . They are JUNK and should not be used.
Some examples of these products are as follows.
“Reinforced” polyester fillers:
These can be aluminum filled body filler for metal surfaces. I is very hard to sand and not good for the finish work (needs a skim coat of a “reg” filler or polyester putty) but will fill much more per coat reg filler and has more corrosion resistance.
A Fiberglass reinforced filler is similar.
Evercoat’s “Metal-2-Metal”, “Everglass”, “Kitty Hair”, “Tiger Hair”
3M’s 05815 Short stand filler, 05813 Long strand filler.
"Regular" polyester body fillers:
Evercoats RAGE or "Lite weight" and others.
3M's Lightweight body filler #058001
Evercoat's "Polyester glazing putty", "Easy sand" and others.
3M's "Flowable finishing putty"#05824 or "Piranha"#05821 .
"Spot putty" (junk, not recommended) Usually found in a toothpaste tube looking container.
Evercoat's "Ever-glaze" #403
3M's "Acryl-green" red or blue #05960,05964,05966
Dupont’s 2286S, PPG’s DFL17
I personally recommend Evercoat products.
“Basics of Basics” Plastic filler
By Brian Martin
What ever tools you use the trick is to not add the last "skim coat' till you KNOW that it is all you need. Don't try to block out that first coat, just use it as a base for the LAST skim coat.
I was taught this procedure after doing bodywork for a number of years and it really works well:
Just apply a nice coat of filler (what ever brand, whatever style, we will put that aside right now). Cut that coat NOT to make it perfect, but to get the basic shape and filling you need as a base for the skim coat. You can cut it with 36 40 or 80 depending on how big the area you are working is. In other words, if you can cut it fast with only 80 then do it. But I would say that this would be limited to an application that is no larger than about 8 inches.
If you happen to have a few high spots, see if you can tap them down.
If you have a few low spots add a bit more filler to ONLY those spots.
Re-cut these last low spots you have just filled with the same grit you have been using (most likely 36).
If you now have a surface that ONE skim coat will fill, then apply it. If you don't work with it a bit more, but NEVER add a little here or there and think you will finish it without a skim coat.
If you have a surface that is very close with only a few VERY MINOR low spots like poor feathering onto the metal, poor transitions from one application of filler to another, or from the metal that is "poking" up here and there you can do the LAST skim coat.
This skim coat is very important, you want it to extend over the COMPLETE area, this is well past the damage you have been working. Maybe as much as 3 inches past the plastic that you have applied to "rough" it out.
This skim coat can be regular filler or a polyester glaze like "Icing" or "Polyester glazing putty", that is your choice, I use both depending on the size of the area being worked. Do not use anything that doesn’t mix with a hardener. NO “Spot putty” in a tube, only polyester putties or fillers. If it uses a hardener, it cures to a hard film. The “spot putties” stay soft and can become even softer when the solvent from the primer coats it.
You now run a block, long board, or hog evenly over this skim coat with a little bit coarser paper than you plan on finishing with to cut off the resin that has surfaced in the filler. I usually just use the 36 or 40 or whatever I have been using on the "rough" work. BUT take CAUTION not to cut much off, you want to JUST take the very top, don't really sand AT ALL.
Now finish sanding with your longboard or block or hog or whatever using the finer paper like 80 on a large area or 120 on that small 8" sized area. Block it out to perfection with a nice feather edge to the surrounding metal.
I can't stress enough, the trick is to know when just ONE LAST skim coat will do the job. And apply it COMPLETELY over the surface. If you only one little low spot in the middle, DON'T just do that spot, skim the ENTIRE thing. You HAVE to have one LAST skim coat over the ENTIRE thing every time. If you get in the habit of this you will do it over and over on every dent you repair and find that you can do just about any dent with just two applications.
As you sand the filler let the board or block you are using run over the surrounding metal. If you only work on the filler you will sand it too low. You need to keep it as high as the surrounding metal, so use the metal as sort of a straight edge that you run the block or board off of.
Don’t worry if you cut through this skim coat here and there. In fact, you WILL most likely cut through. The point of that "LAST SKIM COAT" is that after you add it, you don't add ANY MORE filler. That "LAST SKIM COAT" is just that, the LAST filler you add. If you hit a little filler below, or metal, that is normal and fine. The only thing you are looking for at that point is if the panel is FLAT. The filler skim coat is serving no other purpose than to finish you filler work, it is not a "sealer" or anything like that.
You can add fiberglass resin (“A” coat if you have a choice.) Adding resin was exactly how I learned from the great Emery Robinson (my personal hero in the auto body world). But remember there were no products like polyester putties back then. When you add resin, that resin comes to the top of the film of filler. It is then something you have to deal with. The whole purpose of the SKIM COAT is to put a layer of filler over the top that is easy to block out with as little effort as possible. You want to be able to concentrate on making the panel FLAT, not fighting with gummy resin, sand scratches and the like.
So the polyester putty, though expensive, is what I use.
How is this for an idea: a co-worker of mine showed me this very obvious tip. :)
Add pour-able polyester putty to the regular filler! What an idea! LOL A little pour-able squirted into the "bondo" really thins it out nicely.
The "LAST SKIM COAT" should be left to cure a good long time. Where you may jump on filler and sand it as soon as it is hard, the skim coat should be GOOD AND CURED for an hour or more. If you can of course, in the production shop you may not be able to wait that long. The benefits of the procedure will not be diminished.
A little added note, I have found that I don’t use 36 or 40 grit at all anymore. I went to work at a shop that didn’t use the coarser grits so I had to learn not to also. I have found that using just the 80 and then finishing the Skim coat in 120 or 180 works great, even on large panels.
At this shop it was the first time that I wasn’t doing my own primer work. This meant that I couldn’t “cheat” with a lot of primer and blocking the body work “one more time”. I found that I had to get the work PERFECT, then give it to the painter. I did this in an interesting way, I look at the last skim coat as even a more “final” step. I now look it as “primer”. You see I have used polyester primer, which is like spraying “bondo”. They are both polyester resin based and act and sand very much the same. So, I figured why not just “spread out my primer” as the skim coat! It has worked GREAT, the painter jokingly says, “do you think I’ll need to prime this or just paint it?” I tell him, “Just clear it, it’s a shame to hide that work under primer”.
This method has worked great for me, it’s more of a state of mind than a procedure.
And don’t be afraid to buy the best sand paper and use a lot of it, the cost of the paper will be nothing next to the time and muscles saved. Find the paint store in town that services the PROS the Body shops in town, that is were you will get the right stuff and the right info.
3M has always been my standard for testing sandpapers as they've always offered the best cutting longest lasting abrasives, Carborundum is far less expensive and equal to if not better than 3M IMO. The other brands I've tried don't even come close to this level of performance.
Thanks MARTINSR for more great advice! I can see why sanding was such a chore considering the choice of fillers, but I'm one of those "weird" guys that doesn't mind sanding (not saying that I love bondo--the idea is to use as little as possible). I see it as just one more aspect of the overall resto or rodding project. I get excited with every new area I start on my Corvair. Each job is bringing me closer to completion, but sometimes I wonder if I will be a little sad when that day comes, because I love the "roll up your sleeves and get dirty" type of work. Anyways, just my 2 cents!
BTW: Thanks for the sandpaper info!
Can you please explain the best reasons/applications for using a product like Metal2Metal? I was working with a Body man who swears by the stuff for restoration work, and I came away confused as to why you would use it versus, say, Rage Gold or Extreme-
Thanks Marty/guys, you have to remember this is my first rod and I thought that the tiger hair would be the strongest most durable thing I could use on the old 38. It's all on there now so I have a lot of sanding to do. I notice on shows like Boyd and Foose that they seem to cover the whole entire car with putty. Geese! Cruiz I've been working on this project for 4 years and have been excited about each thing new I've learned but even when I work in my wood working shop I hate the sanding part. I guess it's too boring and repeticious for me. How's the corvair coming? Thanks again for the lesson, Marty. :thumbup:
Fun And Easy
Hey, Mr "I hate sanding", one final tip about slinging mud; don't ever, ever wet sand filler, as the filler will act like a sponge and cause disastrous results under neath the filler called iron oxide, more commonly known as RUST. That is what we are trying to get rid of in the first place, Right? Keep practicing with the put it on and sand it off method and you will be a pro in no time, really. Good luck!!
Honestly, I think if gives your body guy a warm gooy feeling, that is about it.
It's appeal is due to the fact that it looks like lead, even though it is no better than any other plastic filler, and in fact has some disadvantages, IMHO.
I never used the metal 2 metal brand, but a place I worked used all metal filler on the aluminum parts they fabricated. The stuff will set up like a rock and be hard to sand if you wait awhile. Also seemed to get quite a few pinholes to be filled. Its pricey when compared to standard plastic filler. It does seem to have more fill to it though. I was always under the impression that it was good to use first on an area you may have a possible pinhole or something much like fiberglass filler because it didn't absorb water, but after reading the other comments on it, I am now not so sure. Plastic fillers get a bad rap because so many people misuse them, but they are a good product if used correctly. If you do hack work and trowel it on an inch thick and fill holes with it, it won't last or can crack, if used correctly it will last a long time.
How's the corvair coming?
Hey 38 Special,
Thanks for asking about the Corvair; I know it's not a hotrod, and some still don't consider them as "cool" restos, but I love mine. As far as the progress goes, I'm afraid I am having to pack up for the coming Winter since I don't have a garage. I am just about finished with the floorboards--just need to buy the patch panels for the front floor and weld them in. I also have the trunk just about ready for the spatter paint. My goals for next Spring are to drop out the engine to get ready for a complete overhaul (as money provides), and strip the entire body one panel at a time. If money is free, I hope to do all the patch panels (rear wheel wells, etc.) on the body. I'm having a ball!!! I plan to post more pictures soon.
Ps: I agree; sanding isn't too glamorous, just a necessary evil :D
Thanks Jeff, I didn't know that either. Live and learn, eh? :thumbup:
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