Jump to content
SAU Community

Recommended Posts

Posted (edited)
20 hours ago, Murray_Calavera said:

Yep, if you are applying filler it sounds like there is something wrong with the body lol. Safe to assume there is going to be a lot of sanding going on if your still applying fillers. 

Picture a perfect bare metal panel, smooth as glass. You lay down your primer, it's perfect. (why are you going to sand it?) You lay down the colour and clear, it's perfect. No sanding at all took place and you've got a perfectly finished panel. 

You won't be chasing your tail, sounds like you were prepping to start laying filler. If your happy with the body after the sanding, there is some bare metal exposed and some areas with primer, no issues at all, start laying the filler. You are safe to lay filler on bare metal or primer (of course check your technical data sheet as usual for what your filler is happy to adhere to). 

This isn't a 100% correct statement. There is primer that is happy to adhere to smooth bare metal. There are fillers that are happy to adhere to smooth bare metal. Just make sure you're using the right materials for the job. 

Typically if you are using filler, you would go primer, colour and clear. I've never seen any instances before where someone has laid colour over body filler (maybe this happens, but I haven't seen it before). So your plan sounds pretty normal to me. 

Thanks for the info breakdown there. I put some body filler today for the first time, surprisingly it went decently smooth lol. I got the ratio correct both times when I did it, and the dent I had is at least 90% better. I put a guide coat and saw lots of black residue left so I'm putting another batch of putty which I'll need to sand off. 

A few dents I fixed up and checked with the guide coat and they were perfect, no black residue left over. Making progress!

Only thing was after I fixed one spot, I put the epoxy primer to prevent rust. Though, I ran out of time for this other dent that I put filler for, I just put filler instead of the primer first. Raining tomorrow, hopefully the rust doesn't start to set it lol.

Edited by silviaz
2 hours ago, silviaz said:

Thanks for the info breakdown there. I put some body filler today for the first time, surprisingly it went decently smooth lol. I got the ratio correct both times when I did it, and the dent I had is at least 90% better. I put a guide coat and saw lots of black residue left so I'm putting another batch of putty which I'll need to sand off. 

A few dents I fixed up and checked with the guide coat and they were perfect, no black residue left over. Making progress!

Sounds good :)

2 hours ago, silviaz said:

I just put filler instead of the primer first. Raining tomorrow, hopefully the rust doesn't start to set it lol.

Hmm suppose the main thing is, how much do you care about this car? The filler doesn't make for a very good water barrier lol. If there was a tiny little bit of rust forming now, that in 3 to 5 years time becomes obvious under the paint (starts to bubble up), would it bother you? 

Posted (edited)
9 hours ago, Murray_Calavera said:

Sounds good :)

Hmm suppose the main thing is, how much do you care about this car? The filler doesn't make for a very good water barrier lol. If there was a tiny little bit of rust forming now, that in 3 to 5 years time becomes obvious under the paint (starts to bubble up), would it bother you? 

Ah the car is a complete shitbox and not even worth a respray lol, for a professional to do it would probably cost 15k because of all of the dings and stufd but I was keen for a side project. Also solved the problem of being bored haha.

But with the rust yeah I can always fix that in the future, not a huge issue for me.

I found out yesterday that when a dent is created a high spot is created around it (the crown) and to fix it I either need to tap the edges or just sand over it. Which is what made my filler work a bit confusing originally lol.

Edited by silviaz
1 hour ago, silviaz said:

Ah the car is a complete shitbox and not even worth a respray lol

lol nice, I wouldn't worry about sanding back the filler to check for rust then.

1 hour ago, silviaz said:

I found out yesterday that when a dent is created a high spot is created around it (the crown) and to fix it I either need to tap the edges or just sand over it. Which is what made my filler work a bit confusing originally lol.

Yep very much a thing. Personally I don't do the panel beating, its very easy to have a panel beater sort that out for you. If they aren't doing any prep work the actual panel beating generally doesn't take long at all. 

Have you taken before pictures before you started this project? I'd be keen to see the before and afters when you're done.

  • Like 1
8 hours ago, Murray_Calavera said:

lol nice, I wouldn't worry about sanding back the filler to check for rust then.

Yep very much a thing. Personally I don't do the panel beating, its very easy to have a panel beater sort that out for you. If they aren't doing any prep work the actual panel beating generally doesn't take long at all. 

Have you taken before pictures before you started this project? I'd be keen to see the before and afters when you're done.

Yeah I got some before photos I'll show after it's all done and some bodywork progress stuff.

But there's plenty of panels to fix so even if I forgot, plenty of before photos coming up 🤣

  • Like 1
10 hours ago, silviaz said:

I found out yesterday that when a dent is created a high spot is created around it (the crown) and to fix it I either need to tap the edges or just sand over it. Which is what made my filler work a bit confusing originally lol.

Welcome to now being really annoyed at trying to get stretched metal nice and flat again. Or... Fill the low on each side of the high and sand it smooth and forget it has a minor bulge not mirrored in the other panel :P

  • Like 1
2 hours ago, MBS206 said:

Welcome to now being really annoyed at trying to get stretched metal nice and flat again. Or... Fill the low on each side of the high and sand it smooth and forget it has a minor bulge not mirrored in the other panel :P

Yeah. Just sanding that high spot until it's flat with the surrounding panel feels lazy to be honest haha but it's a lot simpler to do. I was wondering why I had a wavy panel after the filler and why it went away when I decided to randomly start sanding it away, then I learned about the crown. 

This is that repair, as you can see the guide coat is still in there so I put more filler, which either will fix the problem or I will realise that the other filler might have been gone just had the high spot which wasn't fixed. It's at least 90% better though. Before I did the repair it was a decent sized dent.

I thought about getting my orbital sander and just sanding in 1 spot to get that high spot low as opposed to going outside the panel, then block sanding it the rest so I don't go too far with the orbital sander. This sounds good in theory but we all know how these jobs go 😂

image.png

1 hour ago, silviaz said:

Yeah. Just sanding that high spot until it's flat with the surrounding panel feels lazy to be honest haha but it's a lot simpler to do. I was wondering why I had a wavy panel after the filler and why it went away when I decided to randomly start sanding it away, then I learned about the crown. 

This is that repair, as you can see the guide coat is still in there so I put more filler, which either will fix the problem or I will realise that the other filler might have been gone just had the high spot which wasn't fixed. It's at least 90% better though. Before I did the repair it was a decent sized dent.

I thought about getting my orbital sander and just sanding in 1 spot to get that high spot low as opposed to going outside the panel, then block sanding it the rest so I don't go too far with the orbital sander. This sounds good in theory but we all know how these jobs go 😂

image.png

I just realised why you go to bare metal on some sections of the repair after sanding the filler, because those crowns are high spots, they are being sanded before where the actual dent is. Simple but interesting stuff.

I was thinking of starting a new thread, similar to "my build" but more my sanding/respray progress. I can post my progress and mistakes that people can learn from. Providing some value to the forum for once haha.

Posted (edited)

I'm having a problem. I think it was mentioned above somewhere but can't see it. 

I'm stuck in the cycle of, sand, filler, low spot again, put filler, sand, low spot again, now i put filler again and a thicker portion which seems to have helped but I got low spots in other areas.

In the image. Circled in red thats where the original low spot was and the shape is the same as the red out line. I've more or less fixed that (still low spot up the top but now I have low spots where the green circled part is. 

Is likely the issue that I didn't start with a course sand paper? I sanded the filler with 240 to reduce the risk of not going to far but maybe the issue is that I'm only taking off enough material to remove some of the filler but not the high spots.

I now started sanding with 120 and I think I'm seeing a difference. I did fix one dent the other 2 are f**ked and seems like I made another low spot which is indicated by the furthest green circle on the left handside.

Any thoughts and solutions?

 

Also second image. All of these rock chips, can they be filled in with primer or do i need to fill them all with filler/putty? So many rock chips on mine lol.

20250521_155844.thumb.jpg.af29228c94d04ef69ad701e61311c647.jpg

20250531_200729.jpg

Edited by silviaz
2 hours ago, silviaz said:

Any thoughts and solutions?

Say you've just laid all your filler and your about to start sanding, how large is the sanding block your using? 

2 hours ago, silviaz said:

can they be filled in with primer

Like a high fill primer? Technically possible but would be a nightmare. Just guessing from the photo, but they look small enough that you might get away with using a 1k spot putty. Normally you'd use something like this on pinholes but with the type of project you're working on I'd give it a go. 

  • Like 1
57 minutes ago, Murray_Calavera said:

Say you've just laid all your filler and your about to start sanding, how large is the sanding block your using? 

Like a high fill primer? Technically possible but would be a nightmare. Just guessing from the photo, but they look small enough that you might get away with using a 1k spot putty. Normally you'd use something like this on pinholes but with the type of project you're working on I'd give it a go. 

Just a standard sanding block size. With the rock chipa they are quite small. I sanded them as you could feel the edges. 

18 minutes ago, silviaz said:

Just a standard sanding block size

I'm guessing you mean something like this size?

https://www.supercheapauto.com.au/p/bodyworx-bodyworx-hard-soft-sanding-block---70-x-135mm/594184.html?cgid=SCA01100303#srsltid=AfmBOoq_qZTEe3boann9BaHiB2f59dxJlosWLzCr0zm_weHgUlDX-N5f&start=6

20 minutes ago, silviaz said:

I sanded them as you could feel the edges

Are they sanded completely flat?

Posted (edited)
11 hours ago, Murray_Calavera said:

Mine's a bit bigger at 70x150mm roughly.

The spots are flat, just can feel the edges if I dig my nail into it. I did fix some other other ones by both using my finger to sand that small spot (I'm a bit wary of doing this and creating hot spots and a bigger mess) and I also did sand over it flat and others, but this also worried me a bit because if I create an overall low spot on the panel on paint that is good. 

Correct me if I'm wrong but as long as it's flat even if I can feel the edges, I can put filler because it will all be level once I sand it?

I can see myself going in a circle after sanding guidecoat with 320 grit if for example the panel is flat with my hand but because I sanded the guidecoat I could have created a low spot again somewhere. Unless where I'm going wrong is what I mentioned previously where I didn't go low enough on the grits.

It's 1 step forward and 2 step backwards here haha. I'll probably need to experiment with it more. Last time I go back to bare metal lol.

Edited by silviaz
58 minutes ago, silviaz said:

Mine's a bit bigger at 70x150mm roughly.

Yep I guessed as much. You'll find life much easier with a large block something like this - 

https://wholesalepaint.com.au/products/dura-block-long-hook-loop-sanding-block-100-eva-rubber-af4437

This is a good demo video of something like this in use - 

 

1 hour ago, silviaz said:

The spots are flat, just can feel the edges if I dig my nail into it. I did fix some other other ones by both using my finger to sand that small spot (I'm a bit wary of doing this and creating hot spots and a bigger mess) and I also did sand over it flat and others, but this also worried me a bit because if I create an overall low spot on the panel on paint that is good. 

You have turned your small rock chip holes into large low spots. You'll need to fill and block these low spots. 

1 hour ago, silviaz said:

Correct me if I'm wrong but as long as it's flat even if I can feel the edges, I can put filler because it will all be level once I sand it?

It's always a little hard not seeing it in person, but yes I would go ahead and lay filler over the whole area.

1 hour ago, silviaz said:

I can see myself going in a circle after sanding guidecoat with 320 grit if for example the panel is flat with my hand but because I sanded the guidecoat I could have created a low spot again somewhere. Unless where I'm going wrong is what I mentioned previously where I didn't go low enough on the grits.

It's 1 step forward and 2 step backwards here haha. I'll probably need to experiment with it more. Last time I go back to bare metal lol.

Have a good look at the video I linked, it's a very good example of all the things you're doing. They went to bare metal, they are using guide coat, they are doing a skim coat with the filler and blocking it back. If what you're doing doesn't look like what they are doing, that's a big hint for you :) 

  • Like 1

Oh I probably didn't speak enough about the small sanding block for blocking large areas. 

In the video about 3 minutes in, he talks about creating valleys in the panel. This is the issue with using a small sanding block for a large area, it's way too easy to create the valleys he is talking about. With a large block its much easier to create a nice flat surface. 

Hard to explain but in practice you'll notice the difference straight away using the large block. 

  • Like 1
5 minutes ago, Murray_Calavera said:

Oh I probably didn't speak enough about the small sanding block for blocking large areas. 

In the video about 3 minutes in, he talks about creating valleys in the panel. This is the issue with using a small sanding block for a large area, it's way too easy to create the valleys he is talking about. With a large block its much easier to create a nice flat surface. 

Hard to explain but in practice you'll notice the difference straight away using the large block. 

To expand on this to help understanding...

The bigger/longer the block is, the more it's going to work to sit on your far away high areas, and not touch the low stuff in the middle.

When you throw the guide coat, and give it a quick go with a big block, guide coat will disappear in the high spots. If those high spots are in the correct position where the panel should be, stop sanding, and fill the low spots.

However, using a small block, you "fall off" one of the high spots, and now your sanding the "side of the hill".

Your little block would have been great for the stone chips, where you only use a very small amount of filler, so you're sanding and area let's say the size of a 5/10cent piece, with something that is 75*150.

For the big panel, go bigger!

 

And now I'll go back to my "body work sucks, it takes too much patience, and I don't have it"

PS, I thought your picture with coloured circles was an ultra sound... That's after my brain thought you were trying to make a dick and balls drawing...

  • Like 1

With stone chips, you really can't just try to fill them. You really have to sand that spot to lower the edges of the chip, so that the filler will end up covering a wider patch than just the chip. Otherwise, you're trying to have a sharp edged paint surface match up to some filler, and they just do not sand the same and you always end up with a noticable transition.

A bunch of adjacent chips should be well sanded back, to round off all those edges, and use a lot (in a relative sense) of filler to raise the whole area back.

5 hours ago, Murray_Calavera said:

Yep I guessed as much. You'll find life much easier with a large block something like this - 

https://wholesalepaint.com.au/products/dura-block-long-hook-loop-sanding-block-100-eva-rubber-af4437

This is a good demo video of something like this in use - 

 

You have turned your small rock chip holes into large low spots. You'll need to fill and block these low spots. 

It's always a little hard not seeing it in person, but yes I would go ahead and lay filler over the whole area.

Have a good look at the video I linked, it's a very good example of all the things you're doing. They went to bare metal, they are using guide coat, they are doing a skim coat with the filler and blocking it back. If what you're doing doesn't look like what they are doing, that's a big hint for you :) 

Thanks for all that info.

I thought I heard that the size of the block should be the same size as the repair or is that wrong? Though I do have some long blocks which I can use for the dents in the middle of the panel. The issue is with the ones at the edge of the door and near the grooves.

5 hours ago, Murray_Calavera said:

Oh I probably didn't speak enough about the small sanding block for blocking large areas. 

In the video about 3 minutes in, he talks about creating valleys in the panel. This is the issue with using a small sanding block for a large area, it's way too easy to create the valleys he is talking about. With a large block its much easier to create a nice flat surface. 

Hard to explain but in practice you'll notice the difference straight away using the large block. 

This is probably what's happened to me. I'll put filler again on my repairs and use the long block and let you know how I go. Fingers crossed it's my last batch of filler lol. I can see that happening where my block dipped at certain points because it didn't cover all the high spots at the same time if that makes sense.

I'm just trying to visualise the fact that with the large sanding block I will be sanding far away from the central dent area and whether that will cause issues or whether that's going to fether out my repairs better.

Posted (edited)
5 hours ago, MBS206 said:

To expand on this to help understanding...

The bigger/longer the block is, the more it's going to work to sit on your far away high areas, and not touch the low stuff in the middle.

When you throw the guide coat, and give it a quick go with a big block, guide coat will disappear in the high spots. If those high spots are in the correct position where the panel should be, stop sanding, and fill the low spots.

However, using a small block, you "fall off" one of the high spots, and now your sanding the "side of the hill".

Your little block would have been great for the stone chips, where you only use a very small amount of filler, so you're sanding and area let's say the size of a 5/10cent piece, with something that is 75*150.

For the big panel, go bigger!

 

And now I'll go back to my "body work sucks, it takes too much patience, and I don't have it"

PS, I thought your picture with coloured circles was an ultra sound... That's after my brain thought you were trying to make a dick and balls drawing...

This makes a lot of sense! I just had that realisation a few minutes ago and wrote it above haha. This is a good new discovery. "Sanding the side of the hill" perfect way to put it.

 

😂 😂 

5 hours ago, MBS206 said:

PS, I thought your picture with coloured circles was an ultra sound... That's after my brain thought you were trying to make a dick and balls drawing...

Edited by silviaz

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • See if you can thermal epoxy a heatsink or two onto it?
    • The other problem was one of those "oh shit we are going to die moments". Basically the high spec Q50s have a full electric steering rack, and the povo ones had a regular hydraulic rack with an electric pump.  So couple of laps into session 5 as I came into turn 2 (big run off now, happily), the dash turned into a christmas tree and the steering became super heavy and I went well off. I assumed it was a tyre failure so limped to the pits, but everything was OK. But....the master warning light was still on so I checked the DTCs and saw – C13E6 “Heat Protection”. Yes, that bloody steering rack computer sitting where the oil cooler should be has its own sensors and error logic, and decided I was using the steering wheel too much. I really appreciated the helpful information in the manual (my bold) POSSIBLE CAUSE • Continuing the overloading steering (Sports driving in the circuit etc,) “DATA MONITOR” >> “C/M TEMPERATURE”. The rise of steering force motor internal temperature caused the protection function to operate. This is not a system malfunction. INSPECTION END So, basically the electric motor in the steering rack got to 150c, and it decided to shut down without warning for my safety. Didn't feel safe. Short term I'll see if I can duct some air to that motor (the engine bay is sealed pretty tight). Long term, depending on how often this happens, I'll look into swapping the povo spec electric/hydraulic rack in. While the rack should be fine the power supply to the pump will be a pain and might be best to deal with it when I add a PDM.
    • And finally, 2 problems I really need to sort.  Firstly as Matt said the auto trans is not happy as it gets hot - I couldn't log the temps but the gauge showed 90o. On the first day I took it out back in Feb, because the coolant was getting hot I never got to any auto trans issues; but on this day by late session 3 and then really clearly in 4 and 5 as it got hotter it just would not shift up. You can hear the issue really clearly at 12:55 and 16:20 on the vid. So the good news is, literally this week Ecutek finally released tuning for the jatco 7 speed. I'll have a chat to Racebox and see what they can do electrically to keep it cooler and to get the gears, if anything. That will likely take some R&D and can only really happen on track as it never gets even warm with road use. I've also picked up some eye wateringly expensive Redline D6 ATF to try, it had the highest viscosity I could find at 100o so we will see if that helps (just waiting for some oil pan gaskets so I can change it properly). If neither of those work I need to remove the coolant/trans interwarmer and the radiator cooler and go to an external cooler....somewhere.....(goodbye washer reservoir?), and if that fails give up on this mad idea and wait for Nissan to release the manual 400R
    • So, what else.... Power. I don't know what it is making because I haven't done a post tune dyno run yet; I will when I get a chance. It was 240rwkw dead stock. Conclusion from the day....it does not need a single kw more until I sort some other stuff. It comes on so hard that I could hear the twin N1 turbos on the R32 crying, and I just can't use what it has around a tight track with the current setup. Brakes. They are perfect. Hit them hard all day and they never felt like having an issue; you can see in the video we were making ground on much lighter cars on better tyres under brakes. They are standard (red sport) calipers, standard size discs in DBA5000 2 piece, Winmax pads and Motul RBF600 fluid, all from Matty at Racebrakes Sydney. Keeping in mind the car is more powerful than my R32 and weighs 1780, he clearly knows his shit. Suspension. This is one of the first areas I need to change. It has electronically controlled dampers from factory, but everything is just way too soft for track work even on the hardest setting (it is nice when hustling on country roads though). In particular it rolls into oversteer mid corner and pitches too much under hard braking so it becomes unstable eg in the turn 1 kink I need to brake early, turn through the kink then brake again so I don't pirouette like an AE86. I need to get some decent shocks with matched springs and sway bars ASAP, even if it is just a v1 setup until I work out a proper race/rally setup later. Tyres. I am running Yoko A052 in 235/45/18 all round, because that was what I could get in approximately the right height on wheels I had in the shed (Rays/Nismo 18x8 off the old Leaf actually!). As track tyres they are pretty poor; I note GTSBoy recently posted a porker comparo video including them where they were about the same as AD09.....that is nothing like a top line track tyre. I'll start getting that sorted but realistically I should get proper sized wheels first (likely 9.5 +38 front and 11 +55 at the rear, so a custom order, and I can't rotate them like the R32), then work out what the best tyre option is. BTW on that, Targa Tas had gone to road tyres instead of semi slicks now so that is a whole other world of choices to sort. Diff. This is the other thing that urgently needs to be addressed. It left massive 1s out of the fish hook all day, even when I was trying not too (you can also hear it reving on the video, and see the RPM rising too fast compared to speed in the data). It has an open diff that Infiniti optimistically called a B-LSD for "Brake Limited Slip Diff". It does good straight line standing start 11s but it is woeful on the track. Nismo seem to make a 2 way for it.
    • Also, I logged some data from the ECU for each session (mostly oil pressures and various temps, but also speed, revs etc, can't believe I forgot accelerator position). The Ecutek data loads nicely to datazap, I got good data from sessions 2, 3 and 4: https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-2?log=0&data=7 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-3?log=0&data=6 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-4?log=0&data=6 Each session is cut into 3 files but loaded together, you can change between them in the top left. As the test sessions are mostly about the car, not me, I basically start by checking the oil pressure (good, or at least consistent all day). These have an electrically controlled oil pump which targets 25psi(!) at low load and 50 at high. I'm running a much thicker oil than recommended by nissan (they said 0w20, I'm running 10w40) so its a little higher. The main thing is that it doesn't drop too far, eg in the long left hand fish hook, or under brakes so I know I'm not getting oil surge. Good start. Then Oil and Coolant temp, plus intercooler and intake temps, like this: Keeping in mind ambient was about 5o at session 2, I'd say the oil temp is good. The coolant temp as OK but a big worry for hot days (it was getting to 110 back in Feb when it was 35o) so I need to keep addressing that. The water to air intercooler is working totally backwards where we get 5o air in the intake, squish/warm it in the turbos (unknown temp) then run it through the intercoolers which are say 65o max in this case, then the result is 20o air into the engine......the day was too atypical to draw a conclusion on that I think, in the united states of freedom they do a lot of upsizing the intercooler and heat exchanger cores to get those temps down but they were OK this time. The other interesting (but not concerning) part for me was the turbo speed vs boost graph: I circled an example from the main straight. With the tune boost peaks at around 18psi but it deliberately drops to about 14psi at redline because the turbos are tiny - they choke at high revs and just create more heat than power if you run them hard all the way. But you can also see the turbo speed at the same time; it raises from about 180,000rpm to 210,000rpm which the boost falls....imagine the turbine speed if they held 18psi to redline. The wastegates are electrically controlled so there is a heap of logic about boost target, actual boost, delta etc etc but it all seems to work well
×
×
  • Create New...