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roo
12-07-2005, 10:34 PM
i did some leading on my vw today and the results weren't too bad. i have a few questions though. first i ground the metal to get rid of any surface rust, then i cleaned the metal with laquer thinner. i applied the tin and heated until brown then wiped it off to reveal a nice shiny surface. then i applied my lead. i kept applying lead and smoothing. should i have to retin after that first initial tinning? i ran out of lead as i only had a few sticks. what should i do next time i want to relead that same spot over the lead i put on today? i wire brushed the lead and did a little filing but its obvious i'll need more. also what should i do once i reach the desired finish with my file? i was once told not to sand lead. i can't remember the reason but it had to do with the aluminum oxide in the sandpaper. if this is true how do i prep the spot for glaze/primer? thanks

Phil V
12-07-2005, 11:21 PM
Roo, I'm one of the last remaining old bodymen who is proficient at using lead as an autobody filler. Years ago I worked at one shop that wouldn't allow us to use polyester filler (bondo - generic term), everything had to be in lead. Having said the previous -- why do you want to use lead on your VW ? The advantages of lead as a filler are few and far between, the disadvantage of using lead are many. The modern polyester fillers we have available today are much better all the way around compared to lead. Once every few years I will still lead a panel either just to prove to myself I can still do a good leadwork repair or maybe to show a friend how the lead work is done. On a very rare occaision a small lead repair might actually be faster than using "bondo". But 99.9% of the time polyester fillers are the best way to go.

The reason you shouldn't sand lead is because it puts lead dust in the air which can cause you lead poisioning. You can sand lead just wear long sleved shirts and long pants, wear a good particle mask to keep the lead out of your lungs. If you grind lead make sure the the pieces of lead flying off the grinder disk are pointed away from you. Those lead pieces can come off that grinder fast enough to actually get embeded in your skin == more lead posioning. Wear latex or nitrile gloves when sanding lead. when you're done sanding - good personal hygiene is very important (take a shower to wash off any lead dust).

roo
12-08-2005, 12:32 AM
the reason for the lead is i am in the process of gapping my hood. i'm hoping for a popsicle stick gap all the way around. its on an edge, a corner, plus its somewhat thick (well over 1/8") so i decided to use lead. probably not necessary but i don't want a crack coming through. i use a charcoal respirator when i lead. it doesn't take long for blue smoke to fill the garage. do the steps i've taken seem right to you? i should be able to keep leading after i tin once correct? good call on the long sleeves and other precautions.

Phil V
12-08-2005, 09:31 AM
This would be one of those rare times when lead is actually better than polyester filler. And yes, you only have to tin once. What are you using for a lead paddle and paddle wax ?

Phil V
12-08-2005, 09:46 AM
Quote " first i ground the metal to get rid of any surface rust, then i cleaned the metal with laquer thinner. i applied the tin and heated until brown then wiped it off to reveal a nice shiny surface" (end quote).

The right way to tin the surface to prepare the panel for applying lead is - you can grind or not grind the metal, it doesn't matter either way. But if there is an rust at all, it must be removed or it will come back to haunt you later under the lead. Next you apply some tinning acid with a brush in the area you want to tin. You then hold the lead stick on one hand the torch in the other hand. Heat the metal ONLY as much as it takes to get the lead molten/liquid. Actually you focus on heating the metal but heat the end of the lead stick at the same time. It doesn't take much lead to tin a good sized area. Use a dry clean rag and spread the tinning lead out to as you said a shiny surface. I was curious when you mentioned blue smoke in the garage from the leading process, there should be very little or no smoke from any of the leading process. As far as heating until brown, that makes no sense to me at all. You only heat the metal hot enough to get the lead to flow out a little in the tinning process. When applying your lead as a filler you then concentrate your heat mostly on the lead stick and a little on the tinned sheet metal only hot enough to get the lead to the consistency of say peanut butter. Thats where the lead paddle and paddle lubricant come in (a tub of bees wax is the top choice for lead paddle lubricant. If you don't use a paddle lubricant then the lead will stick to the wood paddle. The wax will not contaminate the leading process on the car. In the absence of a tub of bees was you can substitute a rag about the size of a wash cloth, pour some motor oil on the folded up cloth, that actually works pretty well for lubing a lead paddle, it won't contaminate the lead work either.

roo
12-08-2005, 11:48 AM
all the leading stuff i have is from a kit available from tptools.
www.tptools.com it comes with paddles, wax, tinning solution, ect. the tinning solution that came with the kit is blue in color that gets brushed on before the lead. it says to heat the brushed on solution until brown. then wipe off with a clean rag (i used paper towel since its lint free). and it leaves a nice shiny tinned surface. i imagine thats what created much of the smoke. i am probably going to order a 10 lb package of tin and some more paddles. that should last me a couple cars or more if i can keep it off the floor.

Doug S
12-08-2005, 12:13 PM
This is a helpful discussion. I too have the exact need for lead for the same reason. I'm gapping the rear fender to the door on an MGA. Any additional tips and information will be most appreciated.
Doug

Phil V
12-08-2005, 05:30 PM
Roo, the tinning acid I used before and still have some now is a red liquid acid. Apparently the stuff you have has lead dust built right in so thats where the shiny tinning takes place on the metal. What we did and occaisionaly I will still do is make sure you have a clean shiny steel metal panel/repair area that needs work. Brush on the tinning acid then hold the stick of lead close to the metal panel so that you are heating the end of the lead stick and the panel at the same time. When the lead gets soft then heat the panel a little more and put some of the lead from the lead stick to the panel. Set your lead stick down and grab a clean rag (or paper towel). Carefully heat the panel in about a 6 inch area and wipe the rag across the lead deposit and the heated panel. A thin layer of lead will be deposited wherever you spread that lead out with the rag while keeping the panel hot enough to melt the lead. That what real tinning was back in the "old days". From there you grab your lead stick and hold it close to the metal so that you're heating the end of the lead stick and the panel at the same time. If you don't heat the panel then when the lead is hot enough to get soft and transfer to the metal but the panel is cold then lead will drop off the panel and end up in a glob on the floor. So as you're heating the end of the lead and the panel at the same time the lead will become soft, make sure that the end of the lead stick is actually molten at the panel then push on the lead stick forward and a little off to the side. This will deposit a decent sized chunk of lead on the tinned steel panel. The trick is in keep the lead hot enough so that its soft enough to work but not so hot that it just flows right down the panel an on to the floor. Try this -- as soon as you transfer the lead from the stick to the tinned steel panel then drop the lead stick and grab your lead paddle. heat the paddle surface that is going to touch the lead for a couple seconds then wipe it back and forth across your bees wax or tallow "lube". Then with the torch heating the lead glob on the panel and heating the area surrounding that glob of lead keep trying the lead with the paddle to see if it is soft enough to move it around. When it gets soft enough to move around then use the paddle to form the lead as you want it. BEFORE YOU DO ANY GRINDING OR SANDING OR FILING OF THAT NEWLY LEADED PANEL LET IT COOL ENOUGH SO THAT YOU CAN WASH IT FIRST WITH LACQUER THINNER THEN WITH A SOAPY WATER SOLUTION. THAT TO REMOVE ANY RESIDUAL TINNING ACID AND BEEF TALLOW/BEES WAX. if all the acid isn't removed then it will continue to work and will cause rust around the lead repair area only by then it will be under new paint. I suggest using a coarse vixen file to rough form the new lead.

Any more questions feel free to ask away.

Doug S
12-08-2005, 06:30 PM
Phil,
I'm planning to use "Nokorode" paste flux in the tinning. Is this OK if I follow your neutralization recommendations?
Thanks,
Doug

Phil V
12-08-2005, 07:15 PM
Doug, I've never used a paste flux. I always did it the old fashioned way. So I can't tell you either way if the paste is a good idea or not.

roo
12-08-2005, 11:03 PM
Hey Phil, can i use lead directly on an edge. like on the edge of a hood or door for gapping or would you use a mig welder to make the edge longer? its 20ga metal or so bent back over itself.

Doug S
12-15-2005, 09:23 PM
The Nokorode worked so-so. I used a presyolite plumbers acetylene torch with a big tip giving a soft flame. Being my first time, it took a while to get used to creating an even heat to maintain the lead within the plastic phase. Was able to close up the door gap where I'd welded in a dlightly mis-matched patch panel. (MGA rear dogleg) . I'll need tu use some regular filler but the edges are all lead. Those old schoolers were artisans!
Regards,
Doug

Phil V
12-15-2005, 10:22 PM
Roo, if the lead isn't sticking out more than 3/16 of an inch you should be fine gapping with lead. Unlike bondo the thicker lead is (within reason) the stronger it is.

Len
12-15-2005, 10:29 PM
In 40 years (66-06) I've never used lead. Do you still use it for any of your standard operations?

Phil V
12-16-2005, 05:42 PM
Len, I almost never do any lead work anymore. On very rare occaisions it is actually faster to lead some spots than it is to use bondo. Most of the leadwork I've done in the last few years was filling in molding holes, screw holes etc.