Is there a trick to keeping the lines straight when blocking?Seems,after I block then recoat with primer for next grit,there is lines around the body line(from the coat below) :confused: Does that make sense?

graemlins/waving.gif
Rick

here is how I do it...

http://www.chevelles.com/showroom/RacnJsn95/sanding.jpg

My body lines come out straight... Never do directly over the body line. Also for the concave, I find that a 2 or 3" piece of PVC pipe with sticky sand paper on it works great!

I'm not sure I was much help, but I'm sure that someone else can explain better. Maybe you already knew this stuff, and I just couldn't understand your question. graemlins/clonk.gif

Are you using a guide coat? If not definately do so. Work the contour or area above the line first and check for straightness. Any missed areas along the line would indicate low areas. Try working above the line for the entire length of the panel, then do the area below the line. Sometimes some masking tape stretched tight just below the line will help define where it should be when you are cutting it straight.

Rick the tape trick works great. I just finished up doing a 01 Ford Windstar smacked down the side. Those windstars have a real visible protruding body line and it got nailed right on the line. I used masking tape during metal work to guide me along the line, also used when sanding filler.

I like to work the line first then worry about the surrounding area. Block the entire length first then come back and block the rest of the panel.

Also watch the area you are sanding. Is the area concave(curves inward) if so you NEED to use something that matches the shape of the panel. If you use a flat board it can dig into the primer leaving you that line you see.

Rick I came across a sweet item the other day, made by 3M called Dry Guide Coat. You apply using a pad much like a makeup pad, its in powder form. By far its the best thing I think for usage during guide coating. So much easier, faster to work with then spray bombs.
Ive been metal finishing a hood for mid 30's farmall tractor and used it to help find the high/lows on bare metal. Even used it a time or two when doing filler work, feel something funky but couldnt pinpoint.

Thanks guys,that's a little clearer. :confused:
I'm headed back out to the shop now and will try again on my fenders and cowl hood...

graemlins/waving.gif
Rick

Eric, yep that 3M Dry guide coat is the only way to fly. I NEVER use any kind of spray guide coat anymore. It puts a perfect fine (fills every single scratch) guide.

I do use it often on plastic filler. After cutting it with 120 I use the guide coat and then block and feather with 180. You can really get things perfect with this procedure.

What is the stuff actually? If you have a low spot or say 36 scratches in your filler, can you put another coat of filler over the stuff or do you need to get it all off? Seems like it could be a pain if you need to remove it completely before priming or adding more filler. :confused:

I have a similar question to 70isfine. The 3M product data sheet on the web says it is lime, carbon and charcoal. What do you do when it remains in a low spot in the primer or bondo? Say you want to put glazing putty in the low spot. (Thinking of a small wave in a door skin). Do you wipe out the 3M powder with wax and greaser remover before you apply the glaze putty?. Or say you have found a low spot in your primer surfacer and just want to spray more surfacer there on your next coat. Again, do you have to remove the powder guide, or can you spay or fill right on top?

Rick another thing to try is wrap the sandpaper over the edge of the block. This way you KNOW when you block up to the line the paper is in contact with the line.

Block Sander (http://www.chevelles.com/showroom/1blocking.jpg)
I like to use adhesive backed paper, mainly cus most of my borads I use cant use the precut sized paper. Also I can fold over the paper easier.
Notice in the pic the paper is folded over the block's edge on the top block, that gives you a more precise cut I believe then having the paper as shown on the lower block.

Guide Coat System (http://www.chevelles.com/showroom/1dry_guide_coat.jpg)
this pic is the dry coat system I use. Althou its a tad pricey at 23 bucks but it does a MUCH BETTER job then a spray bomb and should last pretty long.

Guide Coat (http://www.chevelles.com/showroom/1dry_guide_coat1.jpg)
http://www.chevelles.com/showroom/1dry guide coat1.jpg
This shows the coating on my hood, althou kinda hard to see, it produces a nice uniform coating.

The guide coat is graphite composite. If you apply on filler and find a low spot, just blow it off with air then take a rag with some surface cleaner and it wipes right off.

As for appling filler or primer over it, I dont know but it removes pretty quickly...Eric

P.S RancJason or whatever, could you please explain that pic, Ive been sitting staring at it for the past 10 mins or so :confused: :confused:

on second thought nevermind

70isfine

Team Member


posted 01-04-2004 12:42 PM
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What is the stuff actually? If you have a low spot or say 36 scratches in your filler, can you put another coat of filler over the stuff or do you need to get it all off? Seems like it could be a pain if you need to remove it completely before priming or adding more filler.
To answer your question about the remaining guidecoat in your low areas, just scuff it up with a scotchbrite and blow it clean before any glaze or primer application. The dry guide coat is nice for sure, for what it is-a bit pricey though IMHO. I keep a gallon of Elcheapo black laquer primer on the shelf for use as a guidecoat, A gallon lasts me more than a year.

Hmmm... I've never heard of a dry guide coat, but it makes sense now that I think about it. Thats probably one of the smartest things I've ever seen, when it comes to body work. We always used spray in my auto body class. I probably shouldn't have posted that pic. See, when I sand I do the top of the body line first. I sand down at a 45º angle, and just kinda keep going off the body, and not directly on the body line. If that makes sense. Then I do the bottom side, again leaving the body at the line. I find it makes it nice and sharp, not rounded as if you sanded directly on top of it. I'm no proffessional, but thats how I do it. I didn't get the question at first, after reading it a few more times, what I posted wasn't even an answer for it.

Thanks guys for the info.I have a guy that's a 3m dealer just about 6 miles from where I live(out in the country,that's just down the road a bit)I'm going to go by his house Tuesday nite an get some of the dry coat guide.I don't like the spray stuff when I'm down to the 320 grit stuff,seems to take alot to get it off.Course,maybe I'm not shaking the can enough and I'm spraying it thick..

Another club member(has his own body shop)told me to try PrepSol on my panels.He says it stays wet longer and will show me the highs/lows better than guide coat will.They use it exclusively for that purpose!!???

Hope to have it all ready for paint by this weekend....yeeehaaa :D

graemlins/waving.gif
Rick