|
Post by qreidford on May 31, 2018 21:53:26 GMT
Hi,
I shall probably not update this frequently as I’m far from a confident painter! However as Greenglade has been posting his painting exploits and we are sort of the same stage I thought the comparison of the technologies of the time were quite interesting. The Stirling chassis is the hay cart compared to the Mercedes race car of Flying Scotsman . Anyhow, here’s a couple of the frame primed with red inner frame and waiting patiently for red to cure before masking for the dark brown outer frame colour.
Cheers
Q
|
|
|
Post by qreidford on May 31, 2018 21:59:22 GMT
Couldn’t attach pictures so trying again
|
|
|
Post by Deleted on May 31, 2018 22:01:48 GMT
Now that's looking very nice Q..... a very neat job sir...
Pete
|
|
|
Post by Jim on May 31, 2018 23:29:12 GMT
I second that Pete, it is indeed a great paint job. The nice thing I like about painting as you go is the way a coat of paint be it primer or whatever changes a collection of assembled parts into a single unit that you can see as part of the model to be, if that makes sense.
Great job Q
Jim
|
|
|
Post by qreidford on Jun 21, 2018 23:48:08 GMT
Been busy but here is my bogie painted and lined, can’t say that I’m overly happy but it’s the best I can do and the cat seems to like it😀 Beginning to put things back together now and will post some more Cheers Q
|
|
|
Post by qreidford on Jun 26, 2018 23:11:56 GMT
Painting!! Well slow progress, nitomors to the rescue on the front buffer beam, had to get the white lining done and made complete mess of it so back to the drawing board with a complete strip down and remove all the paint. The plan now is to use the beuglar pen which will give good lines although I find limited mainly to straight lines and just have the patience to wait until base colour has cured....frustrating but it’s the face of the loco .... if I’m happier I’ll post Cheers Q PS what is the preferred solution for cleaning airbrushes which use enamel paints? I have been using white spirit but although I bought a new nozzle which worked great first time around the flow and spread is rubbish, I was using 20 psi and thinned to around 20% with Phoenix thinners but paint not getting through, do I increase the thinners and by how much? Getting very frustrated by this and stripping the brush down to clear blocks is time consuming, any help appreciated.
|
|
barlowworks
Statesman
Now finished my other projects, Britannia here I come
Posts: 874
|
Post by barlowworks on Jun 27, 2018 5:38:07 GMT
I always give my airbrush a blow through with cellulose thinners to clear out any last drops of paint. I have a sealed airbrush cleaning jar sold specifically for this purpose that catches the spray. Very useful.
Mike
|
|
|
Post by Deleted on Jun 27, 2018 5:47:09 GMT
Hi Q
Re white lining...if making a mess of the lining (it happens)..this should only involve a quick wipe with a paper towel or cotton cloth dipped in some white spirit to remove the offending line. This only works if the base colours have been left long enough to cure before lining. If you have been trying to spray over the last few days outside in direct heat...don't...it's too hot....I took the risk as I'm up against the clock...resulting in the use of paint stripper too...lol Afraid I can't type longer now as I'm just going out the door..heading for the coast for an overnight trip... Just wanted to send this to try to help first....
Kind regards
Pete
|
|
|
Post by qreidford on Jun 27, 2018 21:37:55 GMT
Thanks Pete, i’m Spraying indoors in the heat !youre advice is much appreciated. Cheers Q
|
|
|
Post by 92220 on Jun 27, 2018 22:18:46 GMT
Painting!! Well slow progress, nitomors to the rescue on the front buffer beam, had to get the white lining done and made complete mess of it so back to the drawing board with a complete strip down and remove all the paint. The plan now is to use the beuglar pen which will give good lines although I find limited mainly to straight lines and just have the patience to wait until base colour has cured....frustrating but it’s the face of the loco .... if I’m happier I’ll post Cheers Q PS what is the preferred solution for cleaning airbrushes which use enamel paints? I have been using white spirit but although I bought a new nozzle which worked great first time around the flow and spread is rubbish, I was using 20 psi and thinned to around 20% with Phoenix thinners but paint not getting through, do I increase the thinners and by how much? Getting very frustrated by this and stripping the brush down to clear blocks is time consuming, any help appreciated. Hi Q.
20psi is way too low. Use 30psi minimum up to max of 40psi. You may think that is high but if you were to use an aerosol of propellant, that comes out at 50psi. Thin PP paint around 30% thinners. Use the minimum thinners that will spray without leaving an orange peel surface. Do a test on a scrap piece.
To clean the airbrush fully, do as Mike does, spray cellulose thinners through it until it sprays clean. After cleaning up it's a good idea to dismantle the airbrush jets and put them in a small glass jar with a screw lid and let them soak in it in cellulose thinners. That will get the last tiny bits out that just spraying doesn't get out.
Bob.
|
|
|
Post by qreidford on Jun 28, 2018 7:57:30 GMT
Bob, and Pete,
Bob you have confirmed my suspicions that 20 psi was too low and I’ve been finding that I need to thin the paint more than 20% so I’ll try your formula and see what happens, also taking you and Pete’s advice on using thinners to clean the nozzle. Pete, my problem was that after I managed to get a half decent white line using my lining pen, I then foolishly tried to paint the edges in black with a fine brush and cleaning the odd overpaint when pear shaped as I had rushed it. We’ll see what happens this time around 😀 Thanks again I appreciate the help, advice and encouragement.
Q
|
|
|
Post by chris vine on Jun 28, 2018 8:20:53 GMT
Hi Q,
You may be told that 20 psi is too low, but it depends on many things. I painted the whole of Bongo at 15psi with just a small amount of thinner in the paint.
Here are two problems which you may be able to avoid:
1. As you put up the pressure, the paint droplets become smaller. This means that they tend to follow the flow of air from the gun and so they tend to miss the surface. At lower pressures, the paint droplets are bigger so they tend to go in straight lines and end up hitting the surface. At the higher pressures, you will have more difficulty getting the paint to go into the corners: The air has to come back out of the corners and so the smaller paint drops go with it! Also, at the higher pressures, and especially if you are trying to achieve a gloss finish, the higher air pressure can start pushing the paint around and leave ripples. These are the reasons behind the development of the HVLP type of spray guns, High Volume/Low Pressure.
2. It is important to keep the amount of thinners fairly low. Yes, it is easier to get the paint to flow with lots of thinners, but there is a problem with this approach: I found that with lots of thinners, the paint goes on beautifully, but then as it dries, the film thickness reduces as the thinners evaporate out and you can end up with such a thin paint layer that any rubbing down marks start to show through. This is a particular problem with gloss and won't be a problem with satin etc.
So, my advice is to keep the pressure low and use as little thinner as you can get away with. Of course it does depend on what gun and paints etc you are using!! I spent a lot of time going to higher pressures (doing as I was told) and found that it was a blind alley (for me).
Hope this helps. Chris.
|
|
|
Post by qreidford on Jun 28, 2018 20:45:18 GMT
Chris,
So that’s what HVLP means! I’m using my sons Aztec airbrush with limited capacity but the results I get are really variable. One day 20 psi and 20% thinners is ok the next the paint seems too thick and will not flow..I suppose I could blame the weather- but I’m pretty sure it’s pilot error, I have your excellent book but being an Aberdonian cheapskate i decided to use what I had, originally planned to use bespoke rattle cans but the paint shop ended up as an expensive mistake, so back to Phoenix, which I like when I get it to look acceptable!
Thanks again for your advice, I see why many people keep their models in metal - but it will look better 🤞🏻🤞🏻🤞🏻
|
|
|
Post by chris vine on Jun 29, 2018 9:37:51 GMT
Some people say that they prefer the look of their models in metal. But I suspect that is because they don't want to face up to the challenge of painting!!
When painting with not too much pressure and thinner, it can be a problem to get the paint to flow fast enough. Too slow and the coat starts to go tacky before it can flow out flat, result orange peel.
Away for a few days, showing families behind the scenes at the Talyllyn Railway. Chris.
|
|
|
Post by qreidford on Jul 7, 2018 19:23:15 GMT
Update on painting progress, after stripping the front buffer assembly I started again with a different strategy. Although far from perfect, it’s 100% better than the previous effort and now the loco has her/ his face on. However, the gremlins struck again just I was starting to put the brake gear back on....I always knew I had a problem with one side of the rear wheels and kept putting it down to a spring issue. Forced to examine the patient closely I realised after a few measurements that the rear frame was twisted, by around 3/16” so not insignificant. Stripping the newly attached brakes, rear wheels and platework makes me believe that the trouble lies with the main frame stretcher. Reason? Here an extract from the drawings showing the shape of the stretcher. The drawings do not show how this is orientated and I, as others before me, decided the curved section went under the boiler - not so, the cut-out is I think to help avoid hitting the eccentrics and give a fighting chance of fitting and using the blow down valve (so happens the boiler is more of a problem for the eccentrics - which is why I offset my axle pump to help the issue and the cut-out needs enlargement to be able to fit the blow down valve) Anyway by the time I realised my stretcher problem I had to turn it upside down and in doing so I think I made a cock up when spotting through the fixing holes so tomorrow I’ll have to drop the main wheels and all the valve gear and see if my theory is correct. If there is good news I think I have a spare casting for this stretcher, in cast iron which came with a few clarksons castings including a one piece front smoke casting (I didn’t use that) So if I continue to avoid heat stroke, I should know the worst tomorrow. Soothing ale I think 🍺 Cheers Q
|
|
mbrown
Elder Statesman
Posts: 1,717
|
Post by mbrown on Jul 7, 2018 20:14:44 GMT
Bad luck with the stretcher - hope it is rectifiable.
Interesting that several of us have reached the painting and lining stage at much the same time. Your buffer beam looks good and is more ambitious lining than I have so far attempted. From your description, it sounds as if you are getting similar results to me - not quite perfect but improving all the time. I have to say that, from the evidence of the picture your ms is going to looks great.
Malcolm
|
|
|
Post by Deleted on Jul 7, 2018 20:42:07 GMT
Don't worry Q, many have made similar mistakes, I did with my tender stretchers although to be fair I did follow the drawing, Don has a number of parts drawn upside down, he's good at that.. , at least others building Doncaster have made the same mistake so I'm not alone... Painting is looking great sir, lovely neat work... Pete
|
|
|
Post by qreidford on Jul 8, 2018 23:56:01 GMT
So today saw more backward steps, clamped the frames upside down to my table and the rear where the problem seemed to manifest itself measures ok. The front half however reads not ok, not by very much - 15thou at most - my question is what do i do next? Do I leave the back alone and loosen the other stay fixings? Although I saw the problem at the back, my feelings are the problem lies with the four stays from the main stay, to the stay under the cylinders and probably the front stay as well. What’s the technique? Loosen only one side and adjust. Or loosen both sides? Hot and bothered here so help requested. Cheers Q
|
|
|
Post by 92220 on Jul 9, 2018 11:53:14 GMT
Hi Q.
If it was me, I would machine up a locator piece that was a really good fit in the main driver horns, to ensure accurate alignment. Then I would undo one side stretcher fixings, and using parallels, set the frames up on the milling machine table to check how it is sitting. If it all lines up, I'd then re-tighten the stretcher fixings and re-check alignment. This would tell whether it is the fixings or not, that are causing the problem. If loosening the one side doesn't work, I'd then try loosening both sides, and then re-fixing the stretchers one by one, and checking alignment each time. That should tell you where the problem lies. Hope that helps.
Bob.
|
|
|
Post by Deleted on Jul 9, 2018 12:34:26 GMT
Hi Q
I agree with Bob...I'm not familiar with the singles chassis....is the trailing axle fixed in the main frames too?...if so I'd add to Bob's suggestion and machine a piece that's a good fit between the trailing axle too...this along with the piece in the driver horns should keep the frames square while you undo stretchers, retighten checking that things remain square.. I did the same when errecting 4472's frames...I had heavy bars of steel that were good fits in trailing a d leading axle horns to keep all square while the stretcher bolts had their final tightening...this was done on the mill bed to ensure no rock..
Kind regards
Pete
|
|