Painting the bare chassis.

[elrey]

I have just finished 2k priming the bare frame chassis/substructure from my BT7. What a convoluted item to paint. Soon I will apply the finish. Are there any techniques employed to reduce overspray? [masking or such] A systematic approach to painting this frame? Thanx in advance. Mr. Learn by doing

 

[Cottontop]

If all of the chassis will be the same color, what is overspray?

I sprayed my freshly sandblasted chassis

with epoxy primer and spray final coated with single stage gloss black Deltron like THIS...

15 years later it still looks great and almost nothing sticks to the high gloss black.

Tim

 

[nevets]

I'm guessing that the term overspray is being used to describe the unintentional application of excessive paint on an adjacent surface, which can occur when trying to get paint into a tight spot.

 

[elrey]

ZACTLY. Just thought I'd ask as I am trying to do a good job and perhaps there was a tip or two floating around regarding these frames.

 

[nevets]

elrey

I haven't painted a Healey chassis but have done a lot of spray painting of large models, prototypes and some car parts. Assuming you have a quality spray gun and a good compressor with regulator, I have had good results painting in stages, starting with spraying just the hard to get at nooks & cannies, with the spray pattern adjusted to a narrow cone. Then continue with the rest after the initial paint has set up, with the spray pattern adjusted to a broader fan shape.

 

[Cottontop]

I kinda thought that you were talking about what nevets more fully described.

He also described the best process for application and depending on what you are using for the final coat, "overspray" may not be a problem.

I used Deltron and because urethane paints "cure" rather than "dry", within the 20 or so minutes of the first application, any unintended additional laydown should blend/flow-in rather than lump on top.

As an afterthought, what will you be using to apply the paint and have you used it much?

Tim

 

[elrey]

I've got an older Accuspray hvlp siphon gun oowered by a 5hp. 18cfm @ 90 compressor with a couple of air traps and a filter on the gun. I have been getting to know the gun for a few weeks. It is new to me as is auto painting. I also have a supplied air system with full facemask. My paint booth is a 10'x20' Cosco tent with a plywood floor. I have the blower from a large forced air unit exhausting the booth out a 30 ft tube w/filter. My spray experience has up till recently consisted of cabinet work, stair parts, doors, panels and such. Flat stuff.... I applied the primer much as nevets explains and was amazed at the amount of surfaces involved. The gun is top notch with good adjustment and excellent atomization but I found it difficult to spray the entire inside of the motor mount stanchions. I too will be using a single stage urethane for the finish coat. Thank you both for the response.

 

[Brinkerhoff]

elrey , Spraying something like a Healey chassis all at once is a challenge. You need to have complete mastery of your equipment and the material you're spraying. The "overspray" mentioned is where the paint first sprayed does not have enough reducer left in it to stay wet enough to allow the last paint sprayed to melt in to it. Overcome this phenomenon by slowing the dry time of the paint ( mixing in more reducer and a slower ( hotter)temp. reducer than you may think you need and spraying at a cooler outside temperature). The suggested reduction ratios printed on the paint can are a joke in my opinion ( made to satisfy AQMD requirements for low VOCs). You need to add much more. The reducer is just a vehicle to transport the atomized paint to the surface. It breaks up the paint particles and attaches to them , slowing the dry time. Once the reducer evaporates the paint can start to cure. When the reducer has evaporated the paint will be "tacky" and not transfer to your touch. Start by painting all of the tricky to reach areas like the engine mount supports etc. then come back and make longer passes over the top of them. The paint should be wet when sprayed , and stay wet for 40 minutes or so ( the time it will take you to go around the entire chassis). The paint is reduced properly when it sprays out wet easily in a smooth arc of your gun pass. If there is any dry dusty edge to the paint it is not reduced enough. I'll load some pictures to the site if I can figure out how. Good Luck. Kevin

 

[Legal Bill]

If it were me, I'd paint those hard to reach areas with a brush first, at least within an inch or two of the joint areas. No one will ever see them and you can then spray over them after they dry. The brush might do a better job of forcing the primer into the various joints.

 

[elrey]

While experimenting with the paint and primer I discovered that the tech sheet suggestions for reduction were bunk. I've come to the conclusion that they were written by lawyers not painters. This was a surprise to me as I was forced to thin my materials again and again in order for the paints to flow out wet and meld properly. It is a crime to receive poor information from the manufacturer just so they can meet regulations. My initial foray with the primer on a piece of rosin paper hung on the wall yielded a drywall like texture that dried to a sandpaper like finish. Not at all like what was inferred on the can so I reduced the heck out of it [it took much more heck than they claimed] until I got a smooth wet coat that would remain wet long enough to accept more passes without turning to a sandpaper like finish. Unbelievable misinformation. At first I found it hard to believe how far from the truth the tech sheet was, then the awareness set in that the instructions are a legal ruse and have little relationship to reality. This was my first known brush with this type of falsehood in print on an instruction sheet. Thus my question regarding the copious overspray troubles. I am a reader and follower of instructions yet now understand that these are but lies and will try even more reduction and paint in the morn when it is still cool after the fog has lifted. This learning by doing is taking quite a bit of learning and lots of doing. Thank you all for the enlightenment.

 

[jsfbond]

What are you spraying with?...Tip size on the gun?

 

[jsfbond]

80% +- of the reducer is supposed to evaporate in flight from the gun tip to the surface being painted/primed. The proper distance between the surface and the tip is critical.Do not arc the wrist! Practice makes perfect, volunteer to paint your neighbours car first, and learn on that.

 

[elrey]

I am using a #10 aircap w/a .036 nozzle for the 2k primer, and a #8 aircap w/a .028 nozzle for the finish paint. A .051 nozzle was recommended in the literature but was way wrong. I will remember the effect if I ever have to spray anything for the guy that wrote the paper sheet. This is a first series Accuspray from the early nineties. [1990's]

 

[elrey]

This may appear to some to be brazen insanity to paint my Healey as a novice. I have had the thing for years in parts and cannot afford to have it done by another. I just want to drive the thing before I am dead and realize that the time is now. I figure by the time I've painted the chassis and blocked out the body I should have the hang of it. I will certainly know by then whether to proceed with the finish myself or hire a hand for the final. Jobs are scarce so I have some free time and am going for it.

 

[jsfbond]

This may appear to some to be brazen insanity to paint my Healey as a novice. I have had the thing for years in parts and cannot afford to have it done by another. I just want to drive the thing before I am dead and realize that the time is now. I figure by the time I've painted the chassis and blocked out the body I should have the hang of it. I will certainly know by then whether to proceed with the finish myself or hire a hand for the final. Jobs are scarce so I have some free time and am going for it.

I was at that juncture two years ago, I know I did some things wrong, but if memory serves getting in and out of a GT6 is for the young of spine, and gosh darn it I want to drive it!

 

[RestoreThemAll]

I used two paint guns, one siphon and one gravity feed. Using the two different guns made getting into all of the angles and nooks easier, and I didn’t need to refill the cups as often. I put my chassis on a homemade rotisserie at a 45 degree angle. It worked well. I started with the hard to get places, then on to other places that don’t show. Doing the exposed areas (very few) last. My car is black. The final coat was a nightmare. Black just seems to suck up all the light. I couldn’t see where I had left off. I had to paint systematically to make sure that I covered it all completely. My shop does have plenty of lights, as I’ve painted 50 or more cars in it. I added lights anyway. It also helps to use both the right and left hands to spray. By the end of the job, two coats of epoxy primer, and three coats of urethane, my hand grip was weakening. It came to me from Martin Jensen with epoxy primer already on it but sat for several weeks before I painted it. I scuffed the cured primer with brown pads. That was fun. The wife even helped with the scuffing late one Saturday night. Who says we can’t party anymore!

 

[elrey]

Now that I have given the subject some thought I must thank the sneaky lawyers for their ruse. For without such shenanigans there might not be any paint available in California at all.

 

[Randy Forbes]

In my experience, painting my own chassis, I found it best to paint the *higher* surfaces first, as the over spray lands on the panel surfaces below. As you spray the lower panels with overspray on them, the fresh spray rewets the "dusted spray" and melts it in. The results would not be so good in reverse.

As I'm sure you've already found, you'll have to turn (roll) the chassis several times to get complete coverage. I sprayed mine while flat, right side down and left side down to get paint into all the nooks and crannies. It's been over twenty-five (>25) years now, but I probably sprayed it "flat" last.

The Healey chassis was my first attempt at using any spray equipment too, so it is indeed a crash course, but you get plenty of opportunity. I still had the sandblast equipment available, and I seem to recall doing a panel or two over again, if I didn't like the result.

My rookie mistake (and a big one...) was partly to blame on running out of time. Because I was going to loose access to the (open air) facility I was using, I applied the clear coat on a foggy January night in Louisiana. The moisture in the air between the spray gun and the chassis surface resulted in a duller finish. The results don't look bad, it may even be more correct for a production car, but I was striving for more gloss. I had to move the chassis out the next morning, regardless of being finished or not.

Then a day later, I was off to do a three (3) week hitch working in the Gulf of Mexico, so the paint had plenty of time to cure while I was gone.