One-off Harley fender project #1

[hooda]

OK Folks, been a while since I've made time to get on the forum. I've been busy surviving, and even doin' a little bit of WELDING!!! I'm building a custom, '70s vintage shovelhead for my brother-in-law in exchange for a 2001 f250 4x4. I was forced to sell my TIG welder (another story). But still have my purox OA, and the use of my brother's dialarc 250, esab migmaster 351, and brother-in-law's cutmaster 151. So, Here's the start, It's a swap-meet fender that I paid $5.00 for. I decided to mount it as a strutless style. Actually, cutting the struts, shaping them to the fender, and welding them on, so they are part of the fender. I made a tagboard template, and rough cut the struts out of 1/4" hi strength steel plate, using the plasma. I'll tell you what. Having that plasma cutter saved me HOURS versus using a cutting torch to get the jod started, just in slag removal.

[hooda]

I'm not trying to pad my post count for the contest, rather, there's a lot of pics and info, and with my POS internet connection, it's less frustrating to have to re-post a medium sized post that re-construct a huge post when my system stalls out. (Hey-it's more words than "nice weld") It took several hours of fitting, grinding, and re-fitting to get this at least in the ballpark, and I'm under time constraints to get this done. I made the decision to use brazing for this project, mainly to revisit my skillset, and make sure I could still do it. It was real interesting to control the heat input between 1/4 material and 16 gage material. The objective was to make full length seams, as they will be ground down to a concave radius, and must endure not so much load carrying (running a solo seat that does NOT ride on the fender) as the intense vibration that a hi-performance HD generates. Method used was to clamp, spot, clamp, spot, then go back and fill in to blend in. The coolest thing is that whatever unknown alloy my plate stock was, it's incerdibly strong stuff, and gave me ZERO trouble with distortion, or warpage.

[hooda]

I came across these 4-1/2" flap wheels specifically designed to finish up inside fillet welds. they worked perfecrly for this application. My LWS had them in 40 and 60 grit, and what looks to me like 3/8 and 1/2 radius. It was SO nice to dress these braze beads down with such a clean, quick method, and the wheels gave zero trouble loading up with brass. I've since had a chance to hit some aluminum with them, also with great results. Thet even did nicely going around that little stack of washers that I brazed on for a spacer. Using a straight edge flap wheel would habe gouged out areas and caused major headaches come body-filler time.

[hooda]

Here's some shots of the fender after grinding the radius sections, patching the 8 or 9 holes in the middle of the fender, 2 or 3 hours of hammer-and-dolly work, a trip to the blast cabinet, plus a ton of cleanup work inside the fender. When I started, this fender had already been cut and sectioned about 4" by someone who obviuosly used a flux-core, because there were blobs and gobs of weld that the PO opted to just leave hanging. I ground all that crap out of there and filled in all the voids with duraglass, then smoothed it all out. Even though this part of the bike isn'seen, it;s a workmanship thing, as well as making cleaning much easier.At least he did a fair job on the outside getting things fairly cleaned up.

[hooda]

Here's some shots after filling in the major flaws, a little sanding, and some primer. This is as far as I go on this project, as the agreement didn't even require this much, but I wanted to add that "personal touch" to this bike. To get this ready for SHOW-QUALITY paint would require at least 8-10 more hours of detail work and sanding. What I did in this case was blasted the whole fender with a coarse grit, followed by 3 coats of waterproof, fiberstrand filler, followed by 5-6 coats of premium filler, Then 2 coats of primer/surfacer, 2 days dry time, and 2 hours of detail sanding by hand. topcoat is standard sanding-type primer out of a rattle can (i invested in 1 of those trigger type handles so as not to wear out my index finger-best 6 bucks I've spent in a while). Total time invested up to this point a little over 30 hours. This could be accomplished in less time with more proper tools, and more practice. Whaddya think so far?

[jakeru]

Lookin' good, Hooda. What type of bronze rod did you use for the O/A brazing, and also what flux?

[hooda]

Been a while Jake, but to answer your question, I used Hobart pre-flux brazing rod from Northern Equipment, along with Hobart flux in the 1lb plastic container to augment. (I find myself needing to add flux in addition to what comes on the rod). Here's a picture of the nearly completed bike



We're in disagreement over which tires to use. I say the gangster whites, He sez the blackwall. He's now the owner so....

[acourtjester]

Hey Hooda
you might want to check with the paint people but brazing and paint products don't mix.
Some of your hard work may just pop off. check here
http://www.jalopyjournal.com/forum/s...d.php?t=308617
Looks like you need to cover it with lead before any body work.
have fun
Tom

[jerky]

Been a while Jake, but to answer your question, I used Hobart pre-flux brazing rod from Northern Equipment, along with Hobart flux in the 1lb plastic container to augment. (I find myself needing to add flux in addition to what comes on the rod). Here's a picture of the nearly completed bike



We're in disagreement over which tires to use. I say the gangster whites, He sez the blackwall. He's now the owner so....

whites just finish the look, looks awsome

[DaveO]

Looks like you need to cover it with lead before any body work.

Tom-
I scanned through the thread at that link, and saw that one possible technique would be to sandblast the braze work, for instance. Did that article suggest the addition of lead would have to come during the brazing process itself? Or does your note mean you can apply lead afterward?

[Trip59]

I seldom go there... too negative for me. Call your local paint house and talk to them. A bunch of guys doing things in their garage or their parent's garage doesn't make for an expert opinion. Most likely, cleaning/surface prep is a contributing factor (as it is with so many paint failures). Also, modern chemistry has done all sorts of great things, there is probably an etching primer/adhesion promoter, etc. that will overcome the issue of what metal it is.

This guy is a really good friend of mine (the guy who owns the forum, and a top notch custom everything guy http://www.airbrushonline.net/ You could post the question over there and probably get the best answer possible. Tell him Trip sent you.

[DaveO]

... too negative for me.

Too funny, I got that impression too. I was thinking "this is welding web for car painters."

[acourtjester]

HI DaveO
It seems like you would lead over the finished shaping of the brazing. The is what was shown in some other site also. Check into how to use lead on a car as yoiu don't want to use the wrong flux. Lead and car painting has been around for a long time. Just google "painting over brazing". No trying to be a smart A** you put a lot of work in the bike and want to have a great paint job. Its better to have a good base to start with.
Tom

[NRM]

Looks good. I hope the brazing paint issue has an easy fix.
Good luck!

[hooda]

Hey Hooda
you might want to check with the paint people but brazing and paint products don't mix.
Some of your hard work may just pop off. check here
http://www.jalopyjournal.com/forum/s...d.php?t=308617
Looks like you need to cover it with lead before any body work.
have fun
Tom

I've been brazing body panels since I was 14 years old on my 1966 Mustang (first car, total resto, didn't get to drive until I finished it at age 17). Never had a problem with paint adhesion. I blasted the whole fender with a really agressive media (black diamond) then used the waterproof body filler as a base coating to fill the deepest imperfections and the seams INSIDE the fender, followed by regular filler to get it nice. The best thing about this project in that respect is that it's my bro-in-law's bike and his son (my nephew) is having great influence on the paint/color scheme, so other than my INSISTENCE on the gangster whites, they have decided that they want to "murder out" the bike. that means black, flat black, and flat gray. Kids these days call it cool, I call it "LAZY"! What blows my mind is that nowadays, the paint companies have come up with flat freaking black paint packages, 2part, for the princely sum of 200 freaking dollars a gallon and more!!! People with a good knowledge of bikes have already taken note of the fender as being special. Thanks for the compliments!

[ogorir]

the brazing issue(brass in general) in automotive refinish is actually just with applying bondo directly over braze. something in the bondo corrodes the braze, degrading the bondo's adhesion. it could just be because bondo absorbs water, but I think it's one of the components of the styrene or it's activators, personally.

a good 2 coats of epoxy primer will prevent any issues. I (and my dad) use PPG DP series (DP41 is medium gray. I don't remember offhand what red oxide's # is, but you want one of those two. they weight more per gallon, meaning more coating applied, than the other colors, so resist the urge to go with black

DP402 is the faster catalyst. we had some issues with 401 (which needs to sit for 15 minutes after you mix it before you spray it) not curing properly.

you also have a 7 day (with 401) and i think a 3 day window with 402 where you can spray overtop of it without sanding. we always nibbed it with 150 and gave it a light red scotch briting anyway, but it's a bit of extra adhesion insurance.

I agree with you on the new 'flat' trend, although I know why the expensive paint exists. flat paint is HARD to spray and harder to keep looking that way. my grandpa has a radically chopped 37 ford sedan delivery that's 'flat.' it's not really flat, if it were house paint it'd be satin or possibly even semi-gloss. originally it was lacquer, but you couldn't wash it without making it shiny. to be honest, I don't remember what he ended up using. I know it was painted with PPG concept single-stage urethane with flattener in it, but I don't remember if that's what stayed on it.

[Trip59]

Doing a 'satin' job sometime in the next year (painting a friend's bike when I do mine) it was decided to shoot the whole thing in basecoat/clearcoat and flatten the final clear. Easier to shoot and get everything right, and if the final clear gets burnished (making it shiny) it could be re-worked without going through the clear and affecting the paint.

[ogorir]

that'd be how I'd go for a satin finish. the flattening agent starts to make the clear look milky if you go for a true flat look, though. not a big deal for light colors, but who paints anything flat powder blue?