MJM
Promoted Users
If you wouldn't mind, I'd like to see a couple of pictures of the 1st round of blocking 2k primer.
Thank you,
1968 Plymouth GTX
- Thread starter '68 Coronet R/T
- Start date
If you wouldn't mind, I'd like to see a couple of pictures of the 1st round of blocking 2k primer.
Thank you,
'68 Coronet R/T
Oldtimer
Roof with guide coat applied to top half:
I am using a 12" sanding block with 180 grit paper. The idea is to block sand to remove the guide coat, however as you will see, sometimes you will reach epoxy primer and still have guide coat showing the low spots.
Sanding at a 45 degree angle, first one way and then the other.
Here you can see that most of the 2k primer has been removed and areas of epoxy primer are showing. Had I put three coats of 2k Build primer on, some of this would still be covered even though the guide coat was removed. Actually the roof is in pretty good shape right now but I want it perfect so, I will end up shooting more 2k build primer, applying guide coat and blocking it all again, only to remove the guide coat.
The SPI gray 2k build primer could technically be sanded the first round without guide coat because it dries a dark gray and turns lighter when sanded. However, experience as shown me that Guide Coat reveals the imperfections best of all. I use the 3M Dry Guide Coat power.
My trunk lid is going to need even more work, but it had been hit on the rear left at some point and it took quite a bit of hammer and dolly work to even get it close to straight again.
Here is a close up of the cowl where you can see two high spots (epoxy showing) and two low spots (guide coat showing). These low spots will easily cover with another coat of build primer.
Hope that helps?
I am using a 12" sanding block with 180 grit paper. The idea is to block sand to remove the guide coat, however as you will see, sometimes you will reach epoxy primer and still have guide coat showing the low spots.
Sanding at a 45 degree angle, first one way and then the other.
Here you can see that most of the 2k primer has been removed and areas of epoxy primer are showing. Had I put three coats of 2k Build primer on, some of this would still be covered even though the guide coat was removed. Actually the roof is in pretty good shape right now but I want it perfect so, I will end up shooting more 2k build primer, applying guide coat and blocking it all again, only to remove the guide coat.
The SPI gray 2k build primer could technically be sanded the first round without guide coat because it dries a dark gray and turns lighter when sanded. However, experience as shown me that Guide Coat reveals the imperfections best of all. I use the 3M Dry Guide Coat power.
My trunk lid is going to need even more work, but it had been hit on the rear left at some point and it took quite a bit of hammer and dolly work to even get it close to straight again.
Here is a close up of the cowl where you can see two high spots (epoxy showing) and two low spots (guide coat showing). These low spots will easily cover with another coat of build primer.
Hope that helps?
'68 Coronet R/T
Oldtimer
A small piece of sandpaper and my finger. Doesn't take much pressure or sanding.
These are the small imperfections that people often miss. Most of them wouldn't be noticeable after clear coat was applied, cut and buffed, but it's the little things that tend to haunt me, just knowing they are there.
If the low spots are minimal like these, I leave them.
When I come back for the next coat/s I hit Them first a time or 2 depending,give a little flashing time and then do my main shoot. That powder isn't a issue in that tiny amount and the additional primer takes care of the imperfections generally. Or you can hand sand them out and do the same procedure to make you feel better if concerned, But then you digging the hole deeper....
When I come back for the next coat/s I hit Them first a time or 2 depending,give a little flashing time and then do my main shoot. That powder isn't a issue in that tiny amount and the additional primer takes care of the imperfections generally. Or you can hand sand them out and do the same procedure to make you feel better if concerned, But then you digging the hole deeper....
MikeK What if you cleaned those spots with wax and grease remover and penciled them and used your method of prefilling spots of course within the epoxy time window?
The main intent is to identify them and level them up to the last coat level.
Your next coat will likely still have some of the same spots but less proud because you added more dirt to the yard but didn't fill the holes up.
You either deal with the highs and lows early and rid yourself of them or chase them till the end.
Beginning with bare metal.
You'll eventually level it out but at what cost,eventually.
That type guide coat essentially "stains" and no amount of scrubbing with cleaner will entirety remove It. But it's basically irrelevant because you're covering it up anyway and if it's a fairly significant area,and out of window needs some scratch for adhesion.
I see people spray,sand,spray,sand,spray,sand to no end. Why?
I understand getting it Flat....
Start Sooner......
Your next coat will likely still have some of the same spots but less proud because you added more dirt to the yard but didn't fill the holes up.
You either deal with the highs and lows early and rid yourself of them or chase them till the end.
Beginning with bare metal.
You'll eventually level it out but at what cost,eventually.
That type guide coat essentially "stains" and no amount of scrubbing with cleaner will entirety remove It. But it's basically irrelevant because you're covering it up anyway and if it's a fairly significant area,and out of window needs some scratch for adhesion.
I see people spray,sand,spray,sand,spray,sand to no end. Why?
I understand getting it Flat....
Start Sooner......
MJM
Promoted Users
Thank you very much for taking the time to photograph and document the 2k build primer process. I will be spraying 2k this year and was looking for a little guidance. Your pictures and explanation is a great help to me.
Question.....I understand how your going to fill the low spot on the cowel. How are you going to address the high spot, a couple of taps with a hammer? Also, what grit sandpaper will you use for the next blocking session?
Thank you,
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'68 Coronet R/T
Oldtimer
The epoxy showing is usually not a problem, since the guide coat is removed from the surrounding areas, those spots are flush to the surface.
All of this will get more 2k build primer, guide coat and then block sanded with 320 just to remove the guide coat. If everything goes well on that step, I will wet sand with 600 using a soft block. And yes, I use guide coat for that step too.
All of this will get more 2k build primer, guide coat and then block sanded with 320 just to remove the guide coat. If everything goes well on that step, I will wet sand with 600 using a soft block. And yes, I use guide coat for that step too.
'68 Coronet R/T
Oldtimer
I started to shoot two more coats of 2k build primer but only had enough material for 1 coat. UPS didn't deliver my order until late in the day.
Since I had to sand it anyway before putting any more primer on, I went ahead blocked it with 320 grit.
Notice the improvement in the roof with just the one additional coat.
I did find a spot on the trunk lid that was oil canning. Went ahead and fixed that plus a few small areas of metal showing on the quarter panels.
Covered those areas with epoxy primer and then shot 2 more coats of build primer.
Things are starting to shape up:
Going to let this set for a couple of days while I work on the underside.
Since I had to sand it anyway before putting any more primer on, I went ahead blocked it with 320 grit.
Notice the improvement in the roof with just the one additional coat.
I did find a spot on the trunk lid that was oil canning. Went ahead and fixed that plus a few small areas of metal showing on the quarter panels.
Covered those areas with epoxy primer and then shot 2 more coats of build primer.
Things are starting to shape up:
Going to let this set for a couple of days while I work on the underside.
Dean Jenkins
Promoted Users
Looking really good. That body line is going to keep me awake tonight . . . I know how hard that is to get perfect.
'68 Coronet R/T
Oldtimer
I use an Air Gunsa AZ3 HTE2. It has a 2.0 spray tip and I shoot 2k Build primer unreduced.
Most of the primer will be removed when I block sand it with 320 and then wet sand with 600. This car is the QQ1 Bright Metallic Blue, so I will be using SPI White epoxy for a sealer coat.
Most of the primer will be removed when I block sand it with 320 and then wet sand with 600. This car is the QQ1 Bright Metallic Blue, so I will be using SPI White epoxy for a sealer coat.
MJM
Promoted Users
Thank you partner. I've been doing a search for that Air Gunsa AZ3 HTE2 2.0 tip with no luck
Edit: I found this HTE2 model but it only has the 1.8 spray tip.
https://www.amazon.com/Iwata-Air-Gunsa-Hvlp-Primer/dp/B007QV07D6/ref=sr_1_9?adgrpid=1343604386450332&hvadid=83975474802755&hvbmt=be&hvdev=c&hvlocint=140408&hvlocphy=55209&hvnetw=o&hvqmt=e&hvtargid=kwd-83976057021708:loc-190&hydadcr=3280_13533753&keywords=iwata+az3+hte2&qid=1680433516&sr=8-9&ufe=app_do:amzn1.fos.18630bbb-fcbb-42f8-9767-857e17e03685
What about this model ?
https://www.amazon.com/Iwata-IWA9233-Spray-AZ3HV2-20GC-Nozzle/dp/B003YLXNBA
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'68 Coronet R/T
Oldtimer
Bought mine from here: https://spraygunsdirect.co.uk/product/anest-iwata-az3-hte2-spray-gun/
'68 Coronet R/T
Oldtimer
'68 Coronet R/T
Oldtimer
Decided to tackle the underside of the car before going any farther.
Normally I would have media blasted it but after struggling so hard to get all the media out of the body, I did this by hand with stripping discs.
Nasty, dirty job for sure and IF I ever do this again, media blasting will be the chosen method.
Two coats of SPI Epoxy mixed 1:1
Still considering installing some frame stiffeners.
Going to install the doors and front fenders to see how things line up before going much farther.
Normally I would have media blasted it but after struggling so hard to get all the media out of the body, I did this by hand with stripping discs.
Nasty, dirty job for sure and IF I ever do this again, media blasting will be the chosen method.
Two coats of SPI Epoxy mixed 1:1
Still considering installing some frame stiffeners.
Going to install the doors and front fenders to see how things line up before going much farther.