|
|
Aug 16, 2018 12:36:37 GMT
|
I would use a high quality etching primer once it is back from blasting - research the market a little and there are a few paint manufactures / suppliers that have a weld through etching primer which would be ideal in your circumstance if you have welded repairs to undertake on the bodyshell Two things of note in grumpynorthener's post 1- I had never heard of a weld through etch primer. going to have to research that 2- Etch vs Epoxy. For the rank amateur like me, and even more so for people who are facing their first paint job, when to use what primer and when is very confusing. Etch primer in particular confuses the heck out of me since when to use it, ands it compatibility with subsequent topcoats is not clear. I will admit that I took the easy way out many years ago and went with the recommendations of the BASF field tech who told me to use a paint system of: Epoxy-Fillers-Urethane-Paint. When I do use etch, it is out of a can and I use it to cover fresh metal-work. But then I scuff it off because I cant find any data sheets that say it is a suitable substrate for fillers. I do note on my polyester filler data sheet that if etch primers is used to cover any bare metal, then 16 hours must be allowed for the poly filler to cure. At that point I find myself reaching for the epoxy and mixing up a minuscule bit of epoxy ( royal pain that it is to mix and clean the gun for a few square inches of epoxy). Pete
|
|
|
|
|
|
|
Aug 15, 2018 15:15:42 GMT
|
gess thank you. Brave or just stupid. georgeb I was suprised actually how easy bolts and nuts are getting out. I did got some of them stripped, but just couple. Was expecting a bit more fight. gtviva it looks more or less solid, but I know for sure there is hidden "surprises" bjornagn Media blast and then it is a question with what to rust proof it until the body work is done. Any suggestions on that? I like epoxy primers as the first layer over bare metal.Preferably done immediately after media blasting. It is hard to beat the adhesion of an epoxy- to -metal bond and the sheer toughness of the epoxy film. Data sheet on the epoxy I used states that the car could be left outside after coating, would not try that with an acid etch primer. I then do my filler work right on top of the epoxy after a good scuff with 80 grit. The Glassurit product that I use has a chromate additive that optimizes rust prevention from both sides of the film.May or may not be available in your area depending on environmental regulations. www.glasurit.com/en-int/glasurit-801-703-cv-epoxy-primer-filler-chromatI hope you have a good sandblaster. My shell was literally destroyed by the person who blasted it for a previous owner. It took hundreds of hours to smooth it enough that it could then be skimmed with a layer of filer.
|
|
Last Edit: Aug 15, 2018 15:17:20 GMT by bjornagn
|
|
|
|
Aug 15, 2018 14:14:26 GMT
|
Once again... Progress often comes disguised as going backwards. Remember how happy we all were when the car was one color? ( I sure as curse word was!) Well, block sanding is a non-forgiving master. If it aint perfect, the long durablocks will toss your work under the bus and make you face realities you would rather not face. The reality is that the RH door could stand to be fitted better and have the gaps finessed. So.... there went another five hours of work over a week of project time and half a dozen beers. But now I am happy with the fit and the gaps. And by "Happy" I mean that my buddy who helps with this is threatening eithr physical violence or beer deprivation if I don't stop obsessing on the door. I am still going to lay on a layer of Rage Gold to take care of any minor blemishes, but,MAYBE, just MAYBE, I can get back to spraying E36 M3 on this thing by the weekend if I can sneak away from family obligations. The next step is another coat of the featherfill and another round of blocksanding. For those following along at home, the green E36 M3 around the door is fiberglass reinforced filler. I actually spread/bridge it over the door gaps to make a smooth transition from panel to door, then carve the door gap out juuuuuussssttt before it hardens. Then sand with a board across the gap till it is smooth. The fiberglass is less likely to chip at the edges than bodyfill that is a lot softer. Ideally, you still need to fit the door so that the depth of the fiberglass is not over 1/16" . On a positive note, the roof-panel has been declared as done.( see physical violence comment above) It is ready for urethane sealer.
|
|
|
|
|
|
Aug 14, 2018 18:07:51 GMT
|
Seems more solid than I thought at first glance.
What are your plans for stripping the coatings and rust off the shell? Media blast or just manual abrasion technology?
Pete
|
|
|
|
|
|
Aug 10, 2018 17:25:02 GMT
|
I've avoided doing this. I don't think I have it in me to sort out the panel gaps on a Princess. It is actually pretty easy if your eyes are good enough that you can aim the MIG wire at the thin edge of the door! Just one dot at a time and then a layer on top and so on. Better to spend a few hours doing this stuff than regretting the gaps for as long as you own the car. That said, if you are happy with that you see, then you are the only one you have to please. Pete
|
|
|
|
|
|
Aug 10, 2018 14:09:31 GMT
|
Got back out and finished the gap last night Then the Minion who hangs out in the shop pointed out that the new improed gap at the front made the one at the back look a bit less acceptable. So, off we go with the Mig and the grinder once more And since the pointy edge on the doorskin took a bit of a beating when swapping the new skin, I gave it a bit of the same treatment so that it would match the front fender. You can see where I knicked the fender with the grinder and ground through the filler. No matter as I am now going to sand back the coatings on both sides of the door-gap and lay on a spread of fiberglass filler that spand 2" either side. Most of this will be sanded off, but leave a level panel fit either side of the gap.
|
|
|
|
|
|
|
Had a door gap that was Almost "good enough", but my gut was not leaving me alone; it was just too wide and kept catching my eye. So out comes the welder and this happens About five passes with the MIG to build up the edge Bit of flap-flap with the flap wheel whizzy thing Ran out of time or beer, not sure, but left it at that until later where I will file the gap to size. The time to do this was about 15 minutes of work and 10 hours of procrastination. It all adds up!
|
|
|
|
|
|
|
I grew up on a Caribbean island, you did what you had to do with whatever you had to keep stuff working. Parts were not rally available.
Back in the day, we drove around with 5 kids in a Morris Minor Wagon with no doors cause the termites had eaten the wood. We knew nothing of seat-belts and car seats and airbags. Hell, we even drank un-pasteurized milk-products not knowing any better.
In today's litigation crazy society. I have to agree; do it right or do not do it. I wont take on a a project unless the owner is going to do it right, but then again, I am not dealing with people who have zero $$ and need the car to get to work on Monday either. The world has changed. And lets face it, compared to new cars, all classics are the definition of a deathtrap.
Pete
|
|
|
|
|
|
|
As we go down the road of criticizing the work done by previous owners/shops, lets just keep in mind that it was what kept the car from being scrapped at the time, and allowed for it to be brought back at this time. Think of it as a field dressing with a long time to reach proper medical treatment.
|
|
|
|
|
|
|
I don't have a close-up of the wheels and since it is not my car it might take me a bit to get one.
They are pretty much the same as the Minatoyr (sp?)wheels that I have on my GT except they are an Australian version. Are you familiar with the Minatour wheels? Those I can nip out to the shop and take a picture of. They are center-lock alloys where the hug is a big chunk of machined steelbolted to the alloy rim.
The wheels are great in that they run true and don't require inner tubes. They do weigh a ton.
|
|
|
|
|
|
|
|
Just an update for those that like to see stuff conclude... The car is back on its wheel on fully detailed suspension. Leaves for final paint tomorrow and should be painted by the end of the month ready for final assembly.
|
|
|
|
|
|
|
Got out and did the first round of blocksanding; in other words, sanding off all the expensive high fill primer that I just sprayed on the car; you can see it all on the floor.
Have to say I am pretty happy with what I see. This is blocked down with 80 grit to make sure that everything is flat. I am not looking for smooth at this stage, just flat so it is done with coarse paper and I don't go any finer. Nothing too tall or metal poked its head up through the poly primer and I stop when I get to the green epoxy. You can see that most of the poly ended up on the floor.
After a good session of getting dust of the car and the floor, I will do another coat of the poly. That will get blocked out to 320 grit and I will shoot a urethane sealer coat over that for the final blocking before paint. Then everything can sit for a few weeks to outgas.
No way I can make pictures of blocksanding exciting, but here they are as a milemarker in the project.
|
|
|
|
|
|
|
My reaction is positive!
Pete
|
|
|
|
|
|
Jul 31, 2018 18:00:02 GMT
|
If it's polyester based then the size of the mix will effect how fast it cures. A bucket of the stuff will cure much faster than a test-tube of it due to the heat generated during its exothermic curing process not having anywhere to go. When I used to work with fibreglass, if we were worried about cure time we used shallow dishes with polyester resins to increase the surface area and let it loose its heat more easily; it definitely slowed things down compared to the deep tubs we'd use when time wasn't an issue. No idea if that's useful food for thought or just teaching you to suck eggs! Great work on the car by the way! I've been lurking for a while enjoying the build. It'll be a fantastic car and testament to your skills when done. That is a great obseration and I suspect a big part of what happened. The big lump got hot enough that you could not touch it with bare hands. Two thoughts: 1- It bears mentioning something like this in the instruction sheet. 2-As an engineer and someone who knows what an exothermic reaction is, I should have twigged to the runaway thermal reaction. Pete
|
|
|
|
|
|
Jul 31, 2018 15:01:56 GMT
|
This is something that I have found to be very satisfying and enriching and probably destined to be the future of my car hobby when the Molvo is finished. Not so much satisfying in the $$$ way, but because I have met some good people and been able to advance their projects and my capabilities while using their wallets. I have also discovered that in no way would I want to do this as a business; if I could not pick and choose the projects, it would become drudgery in a hurry.
|
|
|
|
|
|
Jul 30, 2018 23:47:55 GMT
|
I have used it before about five years ago and don't recall this issue.
Pete
|
|
|
|
|
|
Jul 30, 2018 17:32:00 GMT
|
You could probably use a laugh at this point. I made this last night That is about $50 worth of poly filler. Funny story..... When they say you have 35 minutes to spray the stuff, they really mean more like 20. AND there were to guns loaded with poly to boot ( another funny story) I can laugh now, but last night it was not funny.
|
|
Last Edit: Jul 30, 2018 17:39:57 GMT by bjornagn
|
|
|
|
Jul 30, 2018 16:09:56 GMT
|
It should not set anywhere near that quick, what ratio were you using? Was it extra fast hardener? If so get some slow hardener. Data sheet calls for a 35 minute pot life, I can tell you that by 20 minutes the gig is up! The gallon of Featherfill comes with four tubes of hardener. The instructions say to mix one full tube to one quart of primer. It occurred to me to use less hardener, but with no experience, was more worried that I would have a car covered in Featherfill that did not harden; been there with the engine compartment paint and would rather not go there again. I can manage by mixing 1/2 quart amounts of the stuff, but the reality is that you need to be cleaning the gun every time you re-load because the clock has started ticking on the remainder of what was in the gun already, so about 4 times per coat on the entire car. I did catch myself thinking out loud that is is a bit silly for a production application.
|
|
|
|
|
|
Jul 30, 2018 15:59:26 GMT
|
Like for the progress, rather than the accidental paperweight there. I can laugh about it now, but last night around 11 pm my sense of humor was not in the building. ¯\_(ツ)_/¯ All part of being an amateur learning new stuff that the pros take for granted. Pete
|
|
|
|
|
|
Jul 30, 2018 14:01:38 GMT
|
It is funny now, but humor was wearing a bit thin last night... Task was dead simple. I had 72 hours to spray the poly high build over the epoxy primer. How hard can it be. Learning a lesson from the epoxy, I mixed up a half gallon of the high build and set at it. Then the stuff was not spraying right out of the gun, so I quick grabbed a different gun and it was working a bit better for a while. Then I noticed that the poly was going off in the gun Yeah, fifteen minute window means 15 minutes and I wasted it farting around with guns that would not spray. So, two guns with solid filler in the works and a $50 paperweight is how I finished the night. Knowing that I had a limited window to spray the poly on the epoxy without having to sand the epoxy first, I went out this morning and tried the gun with a bit of uncatalyzed filler, seeing as it was working I mixed up half quart lots and proceeded to do this The car is now ready for the first session of block sanding. Figure another two coats of poly and a coat of urethane and we should be ready for paint. Pete
|
|
|
|