• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Block sanding vs. "freehand"

Share this page

D

David_Doan

Jedi Warrior
Country flag
Offline
I've just started paint my car, only one door so far. I know that it prefered to block sand, but the door is not quite straight enough for that. The door has zero damage, it just wasn't made perfect in the factory. If I block sand the are high spots that sand down too quickly. Rather than add filler, I've resorted to hand sanding or using a padded block.

Any comments from the paint/body "gurus" as to how best to handle this?

Thanks,

David
 
If there is a high spot that is pronounced, then you need to hammer it back using the "off dolly" method (use youtube for more info).
If there is just a generalize high area then you need to apply several coats of high build primer and block it again. Or if you are really good with filler, then apply a 1/16-1/8" skim coat and block it down.

If you do not block sand the car it will look like you painted over an unprepped car and the paint with amplify all the imperfections.
 
The above comments are right on. If it is a factory flaw it shouldn't be too bad. Rather than filler, a high build primer such as Rust Defender by Z-Chrome is an excellent alternative.
 
Bayless said:
The above comments are right on. If it is a factory flaw it shouldn't be too bad. Rather than filler, a high build primer such as Rust Defender by Z-Chrome is an excellent alternative.
Click to expand...

Yep, thats what I'm talking about - factory flaws. The factory didn't do a great job when they rolled the seams on the door skins for example.
 
One more vote for high-fill primer, a guide coat, and sanding with a short block. It will be quick and probably better looking when top coated than it did when it left the factory.
 
As usual I am on the other side of the coin. Are you shooting for a SHOW car ? Do it all, skim coat, high build primer, sand it 42 times each time getting one micro millemeter closer to perfection. Or are you leaning toward a DRIVER ? Close enough with MINOR high/low spots . Who's going to call you on the "imperfections" ? Most everyone would like a 100 point car but sometime real life gets in the way. Complete the car to a standard YOU can live with. Forget about the spectators and use it the way it was intended to be used ! Bob
 
Bob Claffie said:
As usual I am on the other side of the coin. Are you shooting for a SHOW car ? Do it all, skim coat, high build primer, sand it 42 times each time getting one micro millemeter closer to perfection. Or are you leaning toward a DRIVER ? Close enough with MINOR high/low spots . Who's going to call you on the "imperfections" ? Most everyone would like a 100 point car but sometime real life gets in the way. Complete the car to a standard YOU can live with. Forget about the spectators and use it the way it was intended to be used ! Bob
Click to expand...

I think the fact that I'm painting with a roller indicates that it is not a show car. I'm a decent mechanic, and I can paint parts with a spray can, but this is my first foray into true body and paint. The previous paint was crazed all over from a crappy respray 30 years ago and there were lots of places where paint just popped off. The paint and bondo on the boot were cracked down to the metal. It looked like it had been painted with crackle paint from a hobby store. Tonight I almost finished stripping the boot down to metal. Hopefully the rest of the car can just be sanded.

My goal is for it to look better than before, and for it not to be overtly obvious that it is painted with a roller. If I get a 5 footer, I will be very happy.
 
I think there are a couple of people on the Spridget forum who have applied the Rustoleum paint jobs to their cars with good results. You may want to search for those old threads or start a new topic here asking about it in the subject line so it will attract the right respondents. The pictures I remember them posting looked quite good.
 
Thanks Doug, We had a lengthy discussion about that awhile ago and I decided to do it... Now I am doing it. I was naive, about how much body work I was going to have to do. My car had some hidden surprises.
 
David_Doan said:
I was naive, about how much body work I was going to have to do. My car had some hidden surprises.
Click to expand...

They all do. That's why mine still sports the old patina'd respray it had when I bought it. I know if I tke it apart it'll never get put back together.
 
David,

I know after you've gotten into working on your BE that the simple project to make it look and drive better than before has gotten way more complex than originally planned. Time to regroup and get back to the original plan. We all want them 100% perfect but sometime bondo is needed to get them back on the road and driving. Remember - these cars will continue to rust, they were meant to be disposable not last 50+ years. We're preserving them for the next owner for someone else to drive and enjoy just as much as we have. It's too hot to drive in Dallas right no without AC. Put the plan together so you can be driving come late September when things start to cool down. The joy of a Spridget is in driving not fixing.
 
I'm with ya Jim... My original plan was to have it done by March..... (last March)

I'm taking the week of the 4th off and staying home. I'd really like to have the paint done by then. If everything goes well, I think that is feasible, and it should be on the road by the end of July. Realistically it will prob be august. In either case I will be ready for the fall. Below is my punch list.

After paint the todo list is:

  • New wiring
  • New fuel line
  • Tube shocks
  • Recover dash and door pockets
  • Stripa nd paint wheels (one is done)
  • General reassembly

The already done list is:
  • Stripped and painted all the other parts (engine, tranny, diff, suspension, etc.)
  • Electric tach conversion and calibration (not tested on an engine yet)
  • Rebuilt master
  • Front tilt
  • Alternator conversion
  • Heater delete
  • Calibrated Fuel gauge

Done before the current project started:
  • Seats
  • Carpet
  • Dynamat
  • Interior panels
  • Electric fuel pump conversion
  • General mechanicals and tuning
 
You indicated PreVac pretty much fogged your garage. Any thought to building a temporary painting shed with PVC Pipe. Clear Plastic Sheeting sealed up with duct tape. respirator, Filtered Air coming in through furnace filter, and cheap exhaust fan that ends up blowing exhaust air into say a cardboard box to capture airborne particles for those areas you cannot roll. Park cars away and cover fence with plastic sheeting.

How about smell and odor from Primer. i've got same issue with attached garage and no ventilation and wife with asthma/allergies to smells.
 
The smell and "fog" are both less that traditional spray paint.

the rolled paint smells like kerosene - the bushing thinner is mostly kerosene

I paint with the garage door closed, then open it about 15 minutes later. I had no complaints about smells in the house.
 
Hi David, my '74 is in about the same stage of restoring. I have the driver's door and rear panel left to block. I have had the car for nearly 3 years and am finally getting ready for paint. The car had been painted in haste by the previous owner and it showed. It had been rear-ended and the repair was not very good. It had also not been block sanded. I didn't realize how bad it was until I started blocking it out.

I am going to spray mine. I purchased a HVLP gun from Eastwood. It only uses 4cfm and they claim it produces very little over-spray. I will be using 2-part urethane.And a high fill primer. I would not have invested so much in equipment as I have but I plan on doing my TR6 next. That way I spread the cost over 2 cars.
 
tomshobby said:
Hi David, my '74 is in about the same stage of restoring. I have the driver's door and rear panel left to block. I have had the car for nearly 3 years and am finally getting ready for paint. The car had been painted in haste by the previous owner and it showed. It had been rear-ended and the repair was not very good. It had also not been block sanded. I didn't realize how bad it was until I started blocking it out.

I am going to spray mine. I purchased a HVLP gun from Eastwood. It only uses 4cfm and they claim it produces very little over-spray. I will be using 2-part urethane.And a high fill primer. I would not have invested so much in equipment as I have but I plan on doing my TR6 next. That way I spread the cost over 2 cars.
Click to expand...


I assume you mean blocking after the final coat of primer?
 
The car had never been put back together after it was painted a color change last time which was about 10 years ago. There is no rust so I am getting it as straight as possible before priming. The paint it self is good but I see no reason to paint over the uneven surface especially since it needs to be sanded before priming anyway. I will still block it after priming which won't be as big of a job. In the end the paint won't be much thicker than if it had been stripped first.
 
Back
Top