Modern Vespa

In my hurry to get things done after work last night, I grabbed the wrong can of hardener when I mixed up my primer. No way it was ever going cure. Still sticky when I got home today.

At least it all wiped off pretty easily with reducer. No harm done, but I'm feeling like a dumb-ass.

Round 2 of repriming cowls and primer touch ups. Much better this time.

It's looking like I will be painting the frame separately from all the other bits and pieces.

It's the size of my paint booth as well as my lack of dexterity and attention span in juggling everything at once. I end up backing up into wet paint, tripping over wires or putting my thumbs into things in such a confined space.

The quality of my painting depends directly on my ability to move around a piece with good contrasting lighting and watch each pass overlap and flow out. I guess that's obvious, but it can be hard to do, especially after the first coat.

I did the cowls with a Preval aerosol cannister. I was surprised the primer flowed out as well as it did.

When I'm painting, get everything set up, then rehearse by simulating how I'm going to move the parts around and move myself around each piece to get paint on it. If I find I might bump into something, be unable to see well, or just be unable to re-arrange things to work, I stop and revise my plan.

For my next paint project, I'm going to expand the size of my paint booth just to simplify all of that.

It's frequently still not perfect, but it does allow me to shoot a coat over one side of everything each batch.

That's a good idea. It would be best to shoot it all in one day. Set up so you can get to everything. It's doable with some planning.

Setting up the frame so you don't have to flip it or move it would be a great first start.

You can do the frame in a single shot, but you need a frame to hang it by the swingarm bolt holes. You can then hoist the front up with a cable and hook in the fork hole. Swivel it up and down to get to every angle.

Alternately, if you consider that you have to shoot top and bottom of cowls, mudguards, etc., then you just need to make sure that you have good points to hold it up both top and bottom that won't damage the paint.

I hooked up a hoist "system" last year and it kind of got away from me. I was thinking of hanging the front through the fork tube and having a stand support the back through the swing arm tube. I have a bunch of cheap jack stands that I wouldn't dream of using to hold up my bus, at least not while I'm underneath it. Would be perfect for a dedicated scooter stand though. They are just taking up space.

I watched some videos by Garasi Paintworks. His set up is pretty ingenious. Some of the bikes he gets are pretty rough. But dude lays down some nice paint.

I found that the most practical technique -without rigging up some elaborate rotisserie - is to do the frame in two steps.

Get the frame on a bench about waist high. A swivel helps. Spray the bottom and fender well first, all the way up to the front support on the floor board. After that cures, flip the scoot and do the rest.

That might be an option too. I will try a couple different arrangements BEFORE I paint.

This was how I did the VBB. I also did the cowls and mudguard in two steps. Other than having to do twice as much gun cleaning, it was definitely the best method to not risk messing up one side trying to get to the other.

There is a such thing as over-engineering…said no engineer ever.

I can picture dancing around twirling hunks of metal dangling from the ceiling.

Building dedicated stands is just avoidance of sanding and painting.

Will go with:

Paint bottom/backs of cowls.

Let it cure.

Flip it over.

Paint other side.

Takes me longer to clean the gun than to paint.

I've given this some thought. Not that I've painted a frame or anything, just banging ideas around in my head

I'd paint the bottom of the frame, but have it rigged up with a line through the headset so I can hoist the frame and paint, or maybe an engine mount hole. And I'd tie a wire around the fender pins and hoist them up too.

One shot, or more importantly, cleaning the gun once, and backyard engineered up the wazoo! Ha!

But that's just me - theoretically of course ...

Threw together this painting rack from some scrap lumber and metal. I said I wasn't going to, but it was too easy not too. Expanded my spray booth a bit more too.

I figure the better the setup, the easier (and quicker) painting will go. I have a DeVilbiss Finish line gun, a HF touch up gun and some Preval spray canisters, 'cause it's going on there, one way or another.

A little more sanding left to do…

Some more painting odds and ends:

Found this at Harbor Freight:

https://www.harborfreight.com/painting/paint-sprayers/paint-spraying-accessories/universal-paint-system-starter-kit-17-piece-57508.html

It allows you to spray at any angle without paint dribbling out the vent. The measuring cup is reusable as it's outside of the paint liner. Also picked up another purple gun for $9.

The mess that paint makes is one of the big reasons I have trouble. Makes it hard to focus when you are tracking it all over. That and using guns I never seem to get clean enough. Epoxy primer seems too be the hardest thing to get out of a gun.

Once the spraying is finished, thinners go into the gun straight away.

But spend more time cleaning the gun than actual painting.

And many multiples of painting time is spent prepping.

That's a given…

Let's not calculate Tack rag time…

Yeah, that too.

I'm…still…sanding.

Spent a ridiculous amount of time sanding the mudguard.

Here and there on the scooter, I get bare metal showing through on sharp edges. No high spots that show through…just edges.

Thinking I will just touch them up with the Preval sprayer or a foam brush and sand them to blend. If I did another coat of primer, I would probably end up in the same place. There is plenty of primer on the scooter. Other than edges, I can sand forever and not hit metal.

I got most of the bits and pieces sanded and I also put another coat of primer on the mudguard.

Nothing exciting, except that I shot the primer with a cheap HF spray gun. Up until now I hadn't been able to find a cheap throwaway gun that will shoot primer.

Hand drilling the tip from 1.4 to 2mm made it work quite well. Otherwise, it wouldn't work at all. Hey, if it works for a carburetor… Sanding goes a lot faster when you don't have to go through so much peel. This will be helpful especially when I do the large flat panels on my bus. It would otherwise take a ton of those Preval spray cans.

Getting close to painting but had some questions. It's been awhile since I painted anything. I do remember the "never again" feeling though.

I have a number of places on the frame where I sanded through the primer to bare metal getting it flatted down. They are mostly edges,but other small spots the primer is getting thin.

There are no high spots to bring down or filler to rework and it has been wet sanded down with 600 grit.

I'm trying to decide if it's ready for the top coat or if I should do a sealer coat of reduced epoxy primer on the topside.

Now that I'm finally able to shoot a decent coat of primer, it shouldn't be that much extra work. I would wet sand the final coat with 600 grit or scuff it with a grey scotchbrite pad.

Any thoughts?

If you cut through to bare metal, I usually epoxy layer then have your base primer on top of that.

The other choice is wash primer those areas. But I found sealing the whole thing with epoxy works best.

I agree with you. Looking at my photos on a computer screen instead of a phone, I think another coat of epoxy is a good idea. Touching up and feathering hasn't worked very well and is actually more work.

I have been using a dtm epoxy primer that can be sprayed for build or as a sealer depending on how much it is reduced. It sands easily and has worked out well as the frame is pretty straight.

I think a nice slick coat of epoxy would do it. Except the battery box. I'm taping that off. I'm not sanding in there again.

Don't do any more sanding. Do a reduced seal coat, then get the top coat on it in the recoat window.

I will try, and would love to avoid more sanding. But my chances of shooting a flawless sealer coat are slim, so I might end up having to do a final sanding. We'll see how it goes.

Ah yes, that's a really good point.

Rarely sand epoxy, unless it's a big dust nib or hair etc. the epoxy is dark grey and I will shoot poly primer over it within a day for good adhesion.

I end up sanding that instead. When I see the dark grey, I know I have to stop so you don't cut through. Any problems with the poly primer and I can just reapply.

See how it goes. If you do resand, tape off the edges so you don't get into an endless loop of priming, sanding, burning through, re-priming, re-sanding etc etc.

One last question as part of my paint and primer ANALysis:

My last round of sanding was with 600 grit. I was wondering if I needed to sand it with coarser grade (like 320) before putting on another coat of primer.

Thanks.

I've always done 400 between color (primer included) coats. 600 under and between clear.

The TDS for the primer will tell you which grit to use. It has to be coarse enough for adhesion but fine enough so that the scratches will be covered. If you reduce the primer, you can get away with a finer grit.

Thank you. TDS says 320. 400 would probably be ok too. Sanded it down with 320.

Next time I will use high build before the top coat. The primer I'm using isn't too bad to sand, but probably harder than high build. Even when it goes on glossy it still takes awhile to flat it back with 600 grit.

Just catching up.
Lota my knowledge flows from SoCal and he said most of what I woulda.

He and I recently did some painting on my lathe project.
I beat YouTube to a pulp and found out about hybrid epoxy primers.

Used a PPG product called VP2050.
Others may make similar.

Epoxy so it seals the metal.
Sandable.
High build.

Kinda best of both worlds situation.
Allows single primer material for all priming needs.

Can be reduced down and applied as sealer for use after filler has been used.

Lotta good ideas and perspectives I'm taking from this thread as I think about how I'd paint a frame.

Tks.

Thank you!

The product I'm using is supposed to work the same way. I have used a PPG product similar to what you described and I think it worked better than what I'm using now.

Some products definitely work better than others…like Rage Gold compared to Bondo (TM) body filler. Both will get it done, but the spendy filler is so much quicker and easier to work with.

Still, multiple rounds of priming and sanding comes with the territory. It always seems like more work than expected. It's just a little scooter…but wow, that frame is not an easy thing to sand.

Thanks for all the help!

I gave myself a deadline and a schedule for getting this done, because otherwise it can drag on for ages fussing over small flaws.

All the non frame parts are sanded and ready for paint.

I should be able to reprime the frame tonight and give it a final sanding with 600 grit tomorrow afternoon.

Sunday I will wipe down all the parts and set up the "booth".

Monday, I will have most of the day to paint everything.

Fingers crossed.

Got my last and probably best coats of primer on last night. It was a messy, rushed job, but at least the primer laid down nicely.

One thing I've always had trouble with is choking down the paint gun so I can paint slower, get closer with less overspray. Painting a Vespa feels like filling a shot glass with a fire hose.

I know it's possible to adjust a gun this way, but I haven't found a good video or explanation. I will try out a touch up gun for the top coat, but it still doesn't help with primer.

So restating the question:

How do you set up a paint gun to spray less paint at lower pressure?

Hope that makes sense.

Thanks.

I recommend you spray a very very light coat of black lacquer on everything as a guide coat, then proceed with the wet sanding. You'll find all your low spots and scratches doing this and confirm you knocked down any runs and orange peel.

Hec

I use dry guide coat powder...

+1 on dry guide coat.

Used both spray and dry, dry is much easier to control ann even application and spot low spots.

With spray, it tends to go on patchy and you're not sure if the dark areas are low spots or just because it was sprayed on unevenly.

The technique is to wet sand, using soapy water, until there are no dark spots left. Dark spots are indicative of low spots, scratch's, etc. You wet sand until only primer color is left showing. The guide coat also reminds you of which areas you missed sanding! This is the technique I used when I worked for an English car restoration shop in College. I did many Austin Healy's, Jags, Triumphs and even a 1961 Rolls Royce Princess which was a frame off restoration. We even did a crappy MGB every now and then!

Hec

Yeah I tried it.

Not a fan of using spray. That's probably why dry guide coat exists, because others prefer using it.

I tend to not wet sand poly primer, because it's porous and traps the moisture. The only layer I wet sand is clear coat.

But different folks different strokes. There's a dozen ways to paint.

I use the one that works for my bikes and cars and especially in damp weather conditions.