Bigfella Posted January 2, 2011 Posted January 2, 2011 Today I have started to weld back on some panels. I am having a lot of trouble with the weld thru primer. The mig is Spitting and splattering like trying to weld a dirty panel. I thought the idea of weld thru primer was you could weld thru it. Does any one have some tips for me to get a better weld. It looks like a chicken has S$%t on my weld at the moment. Thanks Matt Quote
C.A.R. Posted January 2, 2011 Posted January 2, 2011 You may have applied it to thickly Matt - try sanding some of it off. Also turn the amps up on your welder. Quote
Bigfella Posted January 2, 2011 Author Posted January 2, 2011 You may have applied it to thickly Matt - try sanding some of it off. Also turn the amps up on your welder. Thanks Lurch Turning the amps up worked a treat. Still splatters but getting good penetration ! Quote
zzzzed Posted January 2, 2011 Posted January 2, 2011 Yes, it should only be put on thinly - so you can almost see through it. Edited to English for you Mick - Lurch. Quote
PeterAllen Posted January 2, 2011 Posted January 2, 2011 When I was welding the rails I was very keen to ensure they wouldn't rust again (too soon). I did a lot of research into rust inhibitors and weld-thru primers, etc, and in the end I threw everything at it. One product that gave me a bit of confidence was Ferguson's Knockout Rust. A good part was that it melted at welding temperatures but it did not disturb the welding process, i.e. you can weld right through it. Quote
Bigfella Posted January 2, 2011 Author Posted January 2, 2011 Thanks Guys. The old rust proofing adds up. $28 for the Weld Thru Primer and $80 odd for the POR 15. But I only want to do it once. Quote
mtopxsecret6 Posted January 3, 2011 Posted January 3, 2011 what welder are you using on it? pre weld primer is supposed to be applied as per normal primer, if its thin enough that it's clear there's no point applying it. You just need more current to penetrate through the primer, though not too much other wise you will start to get undercut and too much heat in the parent material, which will start heat cracking etc etc, another issue aswell is porosity in the weld from the primer. we normally use an arc welder to weld pre weld joints, though im not a qualified boilermaker yet... Quote
C.A.R. Posted January 3, 2011 Posted January 3, 2011 Welding .9mm panel steel is a whole different ball-game, compared to heavy steel fabrication. Try welding panel steel with an Arc Welder & you won't have any panel steel to weld to... And I am a qualified Boilermaker Quote
mtopxsecret6 Posted January 3, 2011 Posted January 3, 2011 turn the current down on the arc welder, and you could do it. I'm still an apprentice at the moment. Quote
C.A.R. Posted January 3, 2011 Posted January 3, 2011 Thread Hijack. turn the current down on the arc welder, and you could do it. No offence mate, try that & see how you go. I tried a few years ago with 1.6mm rods & a good quality Arc welder & I still couldn't stop blowing away the panel steel - even on very low amps. Quote
xa1973 Posted January 3, 2011 Posted January 3, 2011 turn the current down on the arc welder, and you could do it. I'm still an apprentice at the moment. Might want to sit on this one partner...theres a few of us here that do a fair bit of panel and paint work on our own and others rides, suffice to say an arc is not ideal or suited to panel work even on older 50's - 60's - 70's heavier gauge metal..... Quote
Bigfella Posted January 3, 2011 Author Posted January 3, 2011 Keep it nice or the Mods will lock this topic. Quote
Zeddophile Posted January 3, 2011 Posted January 3, 2011 I've been using an arc welder for panels lately..... With a Tig torch attached to it Quote
nat0_240_chevZ Posted January 3, 2011 Posted January 3, 2011 OK back on topic guys...... I use a product from UPOL, its essentially a copper spray, apllied lightly and only 1-2 coats only ie almost can see through it, but dont apply any heavier or arc starting does become harder. I have used other zinc based products that state 'weld through' and they are crap, as zinc burns off and also oxidises around the heat affected area, ie not ideal, its normally too thick even light coats does not seem to help and almost means the application is so light it does not protect anything. The copper has no real adverse affects on any welding in thin panel steel and "in my experience" has had the best results. Zinc sprays have problems in 1-2 years time as they seem to go salty ie oxidise a bit depending its environment and suseptability of moisture ingression. I higly recommend the Upol product, only because of my exp with it, or any other similar products of copper type weld throguh primers. Weld through primers are really i suppose for coating bare metal in which a resistive spot welder is used in repairs. ie weld through not over, as the preimer is there to conduct current to keep the spot as small as possible. HOWEVER all my experience is using a decent mig welder (wia), using a hotter than colder approach does alsways in my exp. give a flater weld with plenty of penatration, always utilising a copper backing/heatsing to keep temps down. always peen arouns plug welds to flatten the area around the plug, this also helps in reducing the weld shrink around it. do sow whilst still red hot. hope this helps, any q's please voice, pm me if you require a response as i may not check this topic. cheers nat0 Quote
Roes Posted February 1, 2011 Posted February 1, 2011 After the welding is done, what products do you use for rust prevention? And what do you guys know about Rust Bullet? Quote
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