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Dazed and Confused
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Discussion Starter · #1 ·
Hi Guys -

This weekend I am picking up my desert doors for my '64 impala which are coming back from a chem dip. They are being coated with a surface treatment to prevent rust until they can be primed.

Anywho, there is some minor work that I have to do to them before they are ready for priming. The doors appear straight to the naked eye, but I want to check them for hi/lo spots. I'm assuming that all my metal work is best done at this point without the primer (correct me if I'm wrong).

1. how can I go about checking for hi/lo spots without a guide coat/primer

2. can anyone recommend some sanding boards and sizes that will work? I did a search on this and there are so many different various boards/sizes, I don't know which end is up :D

3. A buddy of mine (his father runs a restoration shop) said I should heat the pinchwelds of the door to make sure I "boil" all the liquid out of the door before priming. Is there anyway to be sure that the seams are dry?

4. I've got a square palm sander (by dewault) that is used to finish wood. Is there any reason why I couldn't use this to scuff the metal with 80 grit before priming or is a DA prefered for this?

5. FINALLY, is there a reason why most people use a 7-9" grinder (instead of a smaller 4 or 4 1/2") to grind down tack welds?

Sorry for being long winded (its a gift) :D. Thanks for the help!!

Joe
 

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Metal Working Doors

Hey Modas
The method I use for checking bare metal is to pass my hand over the surface. You would be surprised what you can "feel". Sometimes I hold a rag in my hand the "feel" can be enhanced. This takes some practice but it works.
Using a guide coat is a good process but you should use high quality products. Carefully heating the pinch welds will probably help to insure cleanliness but be sure not to over heat the material. It takes very little heat to cause warpage. When you sand the guide coat or bare metal use a 16" or longer long board with 100-180 grit. 80 grit, is in my opinion, is to aggressive. Good work takes time. I work in one direction, make my repair and work 90 degrees the next time and repeat untill the repair is done. Do not push to hard or be excessively heavy handed. The metal will distort under pressure and bounce back causing headaches. Take your time.
7"-9" grinders are heavier and work faster but can cause damage much quicker. I suppose it is an individual thing. I sometimes use a larger grinder for shrinking metal.
What ever methods you use, it pays to practice on someting you do not need or want before stepping up to the real thing. If you practice enough you might be able to save more pieces than you think.
All this is just my way of doing things. There has to be as many ways as there are people. Have fun Agdeuce
 

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Just use a sanding board and or block with 80 grit and run it over the bare metal, the waves will show in the scratches. The seams are what will haunt you after a chemical dip if the acid hasn't been thoroughly washed out. I've never heard of using a torch on them and have no idea if that will work. Just make sure you soak down the seams really good internally with a penetrating cavity wax after the paint work is done, I usually apply a thin coating of seamsealer over epoxy primer to the exterior of the seams and fill the seam with the cavity wax. You'll want a sanded texture with 80 grit if using epoxy primer, any orbital sander will work-your electic will work just fine. When grinding the grinder used should fit the job. Small die grinders work well for weld removal, large 9 inch grinders work well for large areas. I'd buy an assortment of boards and blocks, the most common used are the 18" 9" and smaller.
 

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For checking highs and lows on bare metal there is nothing better then using a sharpie marker and a board sander.
www.imagestation.com/4325757/3960670477
www.imagestation.com/4325757/3960670289
www.imagestation.com/4325757/3985099618

The low spots will remain black marker and the highs will be shiney metal. I use 180 grit on an 17"sander. The marker I use is the magnum from Sharpie its about 2" wide bought from Office Depot for around 3-4 bucks.
Thats what I use when I metal finish, meaning no bondo. Ive found it to provide the bet results.

As for the weld beads I use a small angle die grinder with a disc size of 2" and 3" in 50 grit. I dont own a 4" angle grinder, dont believe they should be anywhere near a car body...Eric
 

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Dazed and Confused
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Discussion Starter · #5 ·
sevt_chevelle -

What a cool idea! That's exactly what I need. Now I just need some sanding boards. I'm assuming you used something flexible?



I was looking at gettting this kit from Eastwood...
http://www.eastwoodco.com/jump.jsp?itemID=1703&itemType=PRODUCT

Has anyone used this kit or can anyone recommend something?

thanks
Joe
 

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I have heard nothing but good regarding the Durablock Sanders, and I have purchased a few. Being the anal person that I am, I decided to try something different, and bought these:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=200057806273&ssPageName=MERC

I am just now finishing the preliminary Body Work on my project, and have been using them for about 2-3 weeks now-they make me feel like a Pro (even though I'm not) and the Rod System really does work-if your budget allows, try 'em-I'm a believer-
 

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Hotrodders.com Moderator
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2,859 Posts
35WINDOW said:
I have heard nothing but good regarding the Durablock Sanders, and I have purchased a few. Being the anal person that I am, I decided to try something different, and bought these:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=200057806273&ssPageName=MERC

I am just now finishing the preliminary Body Work on my project, and have been using them for about 2-3 weeks now-they make me feel like a Pro (even though I'm not) and the Rod System really does work-if your budget allows, try 'em-I'm a believer-
Those are great boards, just don't lend them out, they're hard to get back! Dan
 

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Brian Martin,Freelance adviser
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sevt_chevelle said:
For checking highs and lows on bare metal there is nothing better then using a sharpie marker and a board sander.
Just be DAMN sure, I mean DAMN SURE you get it ALL off before you put anything over it. There is NOTHING, but NOTHING that I have ever seen that will bleed thru primers and paints like felt pen ink.


On the checking of the doors, if you aren't going to metal finish them and will end up using some filler or polyester putty, I say epoxy prime them first thing. Use a block with 180 on it to find high and low spots after it is epoxied. Now, if there are some real bad areas that need shrinking or a lot of hammer work, rough it in a little before the epoxy. But blocking the epoxy (or any primer for that matter) will show you high and low spots pretty quick.

Brian
 

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I use the AFS sanders, they are the ones with the removable rods. Personally never cared for the Durablocks.

Brian, hear you on the bleed thru, been there before :) But I darn near use the marker for every dent ding I do, even if filler will be used. All the guys I work with make fun of me for using the marker, my slap hammer and shrinking disc. But its IMO that I do it faster and better, the better the metal work less the filler work.
Not saying using the marker first is the best way , its A way. Done the epoxy primer method too a few times...Eric
 

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Dazed and Confused
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109 Posts
Discussion Starter · #10 ·
MARTINSR said:
Just be DAMN sure, I mean DAMN SURE you get it ALL off before you put anything over it. There is NOTHING, but NOTHING that I have ever seen that will bleed thru primers and paints like felt pen ink.


On the checking of the doors, if you aren't going to metal finish them and will end up using some filler or polyester putty, I say epoxy prime them first thing. Use a block with 180 on it to find high and low spots after it is epoxied. Now, if there are some real bad areas that need shrinking or a lot of hammer work, rough it in a little before the epoxy. But blocking the epoxy (or any primer for that matter) will show you high and low spots pretty quick.

Brian

Thanks for all the replies Guys. I did a little more research based on the AFS sanding block recommendation and ended up buying a set last night :D

Brian - I was under the impression that epoxy primer didn't sand well (gonna be using SPI). Are there any tricks to sanding epoxy or am I just incorrect that it doesn't sand well

thanks again!
Joe
 

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Joe,

I have used the SPI on my Project, and it sands really well (although it gets me that while it's Black on top when you sand it it's Gray underneath).

I don't have experience with the other Epoxies out there, but it's great even with 80 Grit (I like the Norton Board Paper the best)-
 

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Dazed and Confused
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Discussion Starter · #12 ·
35WINDOW said:
Joe,

I don't have experience with the other Epoxies out there, but it's great even with 80 Grit (I like the Norton Board Paper the best)-

35 -

Thanks! is this the stuff you are using, if so, is it self-sticking or do I need an adhesive to stick it to the blocks?

http://www.azautobodysupply.com/2x1680psabof.html

Joe
 

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boatbob2
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1,385 Posts
metal work

hi,im not the expert,but,ive painted probably 60-70 large fiberglass yachts,and a number of cars. what i do,if the car has been chemically stripped,i take a touch up gun,and spray all seams,and places the chemicals can hide,with ACETONE,do not SMOKE ,it will definitely burn. i spray the areas 3 times,i mean a heavy spray,let the acetone run in to a plastic drop cloth. then put a fan,(NOT if you can still smell the acetone) on the seams. acetone will evaporate fast. i spray the entire body (after sanding ) with an 100 grit paper (on a flex board) brand of board is your choice. i spray 3 coats of epoxy primer. then go to home depot,and buy 2 or 3 cans of their black PAINT, not primer,spray a good DUST coat on the whole car (even 2 or 3 coats ) is ok. let it dry ,i usually leave it over nite. then i sand on the diagonal,both ways . you will sand most of the paint off,leaving only the paint in the dents,scratches etc. after,im done i go back to the places where the paint is still on the body,and outline each place with BLUE masking tape. (this tape can stay on for months if need be,and still comes off easily.then i use a paper towel,or rag,with acetone and remove the paint,leaving the BLUE masking tape. after you think the repair ,is good,remove the tape,spray the black enamel,and board sand again.when no paint remains,youve done an excellent job,i usually finish sand the epoxy with 180 grit. i want some tooth,so the final paint wont peel. pat yourself on the back..not that easy or fast is it???? but,think of all the professionals body men that are crying because they didnt get to spend YOUR money....im boatbob2
 
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