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Post by delaplume on Jun 6, 2020 9:38:42 GMT
Hello all, Just to add a bit if I may, Bob ? I'm assuming Roger that you will be applying transfers, lining etc. after finishing the top coat ??..........If this is the case then go for a matt finish, apply the various items and then seal the whole with a gloss varnish ?? Why not practice on a dummy frame first ?.........you could easily knock up something from some scrap 3mm plate, angle iron and the odd block to represent a cylinder.. Between each coat cover the item with a non-porous material....Those big polythene drawers that are used for under-bed clothes storage are ideal if inverted...and remember to store overnight in a constant temp. environment.... As Bob rightly points out}---- Practice, practice, practice Good luck and plenty of photos please .... PS}------ Here's my alternative 3D printing --------LoL
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Post by Roger on Jun 6, 2020 9:43:31 GMT
Hi Roger. When the mixer is in the tin and it is held in the jig you printed, just gently bring down the drill quill, while revolving, to just rub on the bottom for a few seconds. The mixer will get close enough into the corner to drag out the pigment. Unless the paint has been standing for 2 or 3 years, the pigment won't have gone so hard that a few seconds won't get it loosened. If it is old paint, either break it loose with a screwdriver, as you suggested, or just run the mixer scraping the bottom for around half a minute, at around 1000 rpm. Once loosened, raise the mixing speed to the highest you can without the paint vortex coming over the edge of the tin and painting the workshop. If the mixer just fits through the top of the tin, the max speed is around 1500 rpm. If the mixer is small enough to fit a 50mls tin but you are mixing a 250mls tin, raise the mixing speed to around 2000. Make sure the mixer is always fully immersed while revolving. When i painted my frames, I made a metal plate to match the mounting flange of the cylinders and bolted that in place of the cylinders, to mask the area. Any masking would do for this, and you are right. Cylinders should be metal to metal, as should the rest of the frames assembly. Then I masked the sliding surfaces of the horns. Everything else got painted. This is where bead blasting is better than grit blasting. With grit blasting, any dampness in the air can cause flash rusting within seconds. Bead blasting doesn't have anywhere near such an aggressive action and flash rusting is much less likely. You are right in thinking that a number of thinner coats are better than one thick one. Just remember though that using several coats of a colour to get the paint thickness, will give you less than a full gloss finish. That might actually be what you want. Using several thin coats, built up, can give almost any finish from eggshell up to around a 90% gloss. If applying several coats, it is worth experimenting to see what sort of finish you will get as it depends on how thin the paint is, what air pressure you are using, and how far away from the surface the spray nozzle is. Spraying distance can vary the final paint finish from full matt to full gloss too, so it is important when using several coats of thinned paint, to try and keep the spraying distance as near constant as possible. This is not recommended for anyone wanting a matt finish though as the paint will have partially dried between gun and surface, and will lose adhesion. For our work, the ideal spraying distance is around the 2" (50mls) mark, and definitely not more than 3". The amount of thinning and the air pressure should be adjusted to enable spraying at this distance and achieving the wet surface without runs. You can tell if you are too far away as the sprayed surface should appear wet, to flow out, for a short while after the spray cone has moved on, but not wet enough for the paint to make runs. I'm afraid it's practice practice practice, to get the perfect finish. Starting with the frames is good because the finish can be anything from mediocre to excellent and generally they look the same after everything is fully assembled. It's the boiler, tanks and cab that everyone focuses on! Bob. Hi Bob, That's great, I'll make two mixers for the two sizes of tins. I've got both gloss and matt black which I intended to use to have a less glossy finish on the frames. Actually, I don't like the full gloss look on the rest of the locomotive. There was a locomotive like that at the Midlands ME Exhibition, and it really put me off the idea. It looks to Toy like in my opinion, and it must be a nightmare to keep looking good. I'd prefer to take that excessive gloss away. I presume you like the Air Brush for jobs like this because you can work your way around the shapes and angles from a relatively short distance away. It's hard to see how you'd use a larger gun on the inside of the frames and still get into the corners. Would you still use the Air Brush for the Pannier Tanks, even though the sides are quite large areas? The ends and tops have brackets and steps, so I can see why you would want to use the Air Brush for those. It's certainly going to be interesting.
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JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,956
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Post by JonL on Jun 6, 2020 9:46:12 GMT
My son uses matt paint for all his models and then uses a gloss or a matt clearcoat for the finish he desires. It's very effective.
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Post by Roger on Jun 6, 2020 9:47:35 GMT
Hello all, Just to add a bit if I may, Bob ? I'm assuming Roger that you will be applying transfers, lining etc. after finishing the top coat ??..........If this is the case then go for a matt finish, apply the various items and then seal the whole with a gloss varnish ?? Why not practice on a dummy frame first ?.........you could easily knock up something from some scrap 3mm plate, angle iron and the odd block to represent a cylinder.. Between each coat cover the item with a non-porous material....Those big polythene drawers that are used for under-bed clothes storage are ideal if inverted...and remember to store overnight in a constant temp. environment.... As Bob rightly points out}---- Practice, practice, practice Good luck and plenty of photos please .... Hi Alan, That's an interesting point about the transfers. Yes, there will be a transfer on the side of the Pannier Tanks, but the rest is just lined. Is it necessary to varnish the whole tank though? Couldn't you just carefully varnish over the transfer so that it just covers the edges?
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kipford
Statesman
Building a Don Young 5" Gauge Aspinall Class 27
Posts: 573
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Post by kipford on Jun 6, 2020 10:07:17 GMT
There is the theory that transfers are more easily applied to a gloss surface. In the 4mm world we normally use gloss, though I often go for satin, apply transfers, then either use matt, gloss, satin, mix a bit of black in it or whatever varnish to achieve the final effect. Dave
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Post by Roger on Jun 6, 2020 11:24:52 GMT
There is the theory that transfers are more easily applied to a gloss surface. In the 4mm world we normally use gloss, though I often go for satin, apply transfers, then either use matt, gloss, satin, mix a bit of black in it or whatever varnish to achieve the final effect. Dave Just a stupid question... can't you just apply the transfers and leave it at that? If they get damaged, you can always apply a new one?
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Post by simplyloco on Jun 6, 2020 11:30:11 GMT
There is the theory that transfers are more easily applied to a gloss surface. In the 4mm world we normally use gloss, though I often go for satin, apply transfers, then either use matt, gloss, satin, mix a bit of black in it or whatever varnish to achieve the final effect. Dave Just a stupid question... can't you just apply the transfers and leave it at that? If they get damaged, you can always apply a new one? Not at £17.50 a GNR pair you don't! John
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Post by Roger on Jun 6, 2020 11:38:27 GMT
I thought it was easiest to quickly put the buffer stocks back on so I could use the turning frame to move the frames around while scribing the masking lines round the many components that need it. The buffer beams and pump stretcher are going to be permanent, and possibly the brake stretcher, but I'm not sure about that one yet. The massive stretcher under the cab is going to be removable because that may well need to have modifications done to it when the piping up is done. It may also need additional brackets for the whistles. It will make life easier if I can get that out for machining. 20200606_113309 by The train Man, on Flickr I might leave the 'I' section bracket area painted and just open out the holes in the brackets. We'll see. 20200606_114246 by The train Man, on Flickr The Smokebox Saddle is a metal to metal stretcher so that needs masking too... 20200606_114735 by The train Man, on Flickr ... as do the cylinders... 20200606_120705 by The train Man, on Flickr ... and the Gear Frame. I've scribed all of these deeply so they will still be visible after shot blasting. 20200606_121902 by The train Man, on Flickr 20200606_121912 by The train Man, on Flickr
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Post by Roger on Jun 6, 2020 11:44:17 GMT
Just a stupid question... can't you just apply the transfers and leave it at that? If they get damaged, you can always apply a new one? Not at £17.50 a GNR pair you don't! John Hi John, That seems a bit steep. I've just looked up the BR ones from Phoenix Precision and they're £9 a pair.
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Post by simplyloco on Jun 6, 2020 12:45:40 GMT
Not at £17.50 a GNR pair you don't! John Hi John, That seems a bit steep. I've just looked up the BR ones from Phoenix Precision and they're £9 a pair. Amortisation rules Roger. BR transfers probably move more quickly.
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kipford
Statesman
Building a Don Young 5" Gauge Aspinall Class 27
Posts: 573
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Post by kipford on Jun 6, 2020 12:51:08 GMT
Roger Transfers are easily damaged and you will soon get fed up with the cost and effort of having to replace them and the damage that does to your lovely glossy paint finish. Varnish also tends to blurr out the transfer backing film edge lines which cannot be avoided. Dave
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Post by simplyloco on Jun 6, 2020 13:10:20 GMT
Roger Transfers are easily damaged and you will soon get fed up with the cost and effort of having to replace them and the damage that does to your lovely glossy paint finish. Varnish also tends to blurr out the transfer backing film edge lines which cannot be avoided. Dave Good advice Dave. I'm not putting any transfers on the Stirling until it has passed its tests and is on the display stand! John
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Post by Roger on Jun 6, 2020 13:15:49 GMT
Roger Transfers are easily damaged and you will soon get fed up with the cost and effort of having to replace them and the damage that does to your lovely glossy paint finish. Varnish also tends to blurr out the transfer backing film edge lines which cannot be avoided. Dave I wonder if you could just make a mask and spray over the transfer and just cover the edges then with a very thin coat of varnish?
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timb
Statesman
Posts: 512
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Post by timb on Jun 6, 2020 13:22:43 GMT
Slightly different Roger but I used Humbrol matt varnish brushed onto decals for Airfix models and you could not tell there was varnish on them and they never peeled I assume they are a similar item. I am not sure how this would effect any additional painting though.
Perhaps try a few different finishes with some cheap decals on scrap painted steel and see what turns out best, lots of cheap waterslide transfers on Amazon for instance.
Tim
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Post by Roger on Jun 6, 2020 19:41:06 GMT
I'm just doing a few odd jobs at the moment while waiting for some parts to be delivered. This is an experiment with a piece of fine Brass gauze dropped into the bottom of the axlebox pocket to make sure that oil still finds its way into the feed holes which you can just see to the left and right of the reservoir. 20200606_202135 by The train Man, on Flickr Although this cover will stop a lot of debris getting into the oil, it can still happen, so I'd like to filter that. I'll hold these in with a couple of drops of Threadlocker because they have the unfortunate habit of sticking to the top face of the horn if the axlebox is pushed right to the top. Although this is probably not going to happen in practice, it's not good if it does. That's because the cover doesn't easily drop back in place, so I'd lose about 2.5mm of travel. In case you're wondering what those four small holes are for... they're to let the air out else you can't fill it through the middle hole. If you recall, I put a tiny hole in the side of the reservoir to oil the horns. However, I've forgotten to add a clearance on the side of the cover plates to let the oil get to the holes. I'll have to sort that out next. 20200606_202151 by The train Man, on Flickr This is the Smokebox door ring. Originally I made it to be a snug fit in the smokebox, but I've subsequently realised that there's no room for any paint on either of these parts. So here I'm very lightly holding the inside of the flange on the jaws with a drop of permanent Loctite to keep it from slipping while I turn the outside. I've turned it so one of the pieces riveted to the inside is butting against one of the jaws in the direction it will resist the cutting force. 20200606_162140 by The train Man, on Flickr And here's the first use of the Diamond Toolholder. I'm using this with a sharp corner so that there's the smallest possible cutting force. I'm also only taking 50micron (2 thou) cuts so it doesn't end in tears. Altogether I've reduced the diameter by 0.5mm which feels about right. We'll see. 20200606_163106 by The train Man, on Flickr
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Post by Roger on Jun 6, 2020 20:50:04 GMT
These are the axlebox reservoir covers with the feed holes added to the ends for the hornblock lubrication holes. The holes in the reservoir are deliberately placed near the top so that they don't get over oiled. The holes are only 0.4mm and you only get a smear of oil but it really only needs enough to make sure it's not running dry. If it needs a little more, I can open out the holes a little to let more through. 20200606_214340 by The train Man, on Flickr You can just see the oil hole near the left end of the axle block 20200606_215118 by The train Man, on Flickr
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Post by chris vine on Jun 6, 2020 21:22:59 GMT
Hi Roger,
for transfers, I found it best to cut away as much of the backing as possible, IE take the triangular bits out of Ns etc. then, after applying, drying etc, I applied a slightly thinned varnish/lacquer with a long brush and with a head magnifer. I just went about .5 mm over the edges to seal them onto the paint.
On Bongo, I didn't apply varnish over the whole surface after painting. Although many people seem to do this, including on many cars. The advantage is that you can flat down the paint and take out any ripples or blemishes and then apply the varnish over that. It brings it back to gloss (which is good on coachwork parts I think) but is much easier to spray than the actual paint as it seems to flow much better without the pigments.
I found that airbrushes etc, didn't put the paint down quickly enough (at least on parts the size of Bongo's tender) to let the paint flow and pull out flat.
Chris.
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jma1009
Elder Statesman
Posts: 5,913
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Post by jma1009 on Jun 6, 2020 22:04:37 GMT
I think you are all getting a bit too absorbed in all this without seeing the bigger picture.
GWR locos were generally badly painted in 'A' shop. There was no dedicated paint shop, and all paint was applied by brush.
The 15XX class probably came within the period of commercial tins of paint. But gloss black is gloss black. That is what these locos were painted with. There is substantial photographic evidence of this.
I've never known of waterslide transfers deteriorate, and, yes, they should best be applied to a gloss paint surface. And I've never used varnish on a miniature loco either.
You stir a tin of black gloss enamel to paint a 15XX just as they do on the SVR, and many of us do in our workshops. You don't have to stir up pigments at the bottom of the tin for black gloss, or stir it around at 1000rpm scratching the bottom of the tin; it is black gloss enamel after all.
Cheers,
Julian
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Post by Roger on Jun 6, 2020 22:05:12 GMT
Hi Roger, for transfers, I found it best to cut away as much of the backing as possible, IE take the triangular bits out of Ns etc. then, after applying, drying etc, I applied a slightly thinned varnish/lacquer with a long brush and with a head magnifer. I just went about .5 mm over the edges to seal them onto the paint. On Bongo, I didn't apply varnish over the whole surface after painting. Although many people seem to do this, including on many cars. The advantage is that you can flat down the paint and take out any ripples or blemishes and then apply the varnish over that. It brings it back to gloss (which is good on coachwork parts I think) but is much easier to spray than the actual paint as it seems to flow much better without the pigments. I found that airbrushes etc, didn't put the paint down quickly enough (at least on parts the size of Bongo's tender) to let the paint flow and pull out flat. Chris. Hi Chris, Thanks for that, I like the sound of the way you did the transfers, I'll probably do the same. I can see how getting enough paint down quickly might be a problem on those bigger areas. I've got a bigger gun that I might have to use for that then. I imagine I'll have to use the Air Brush on places where there are steps and other obstacles though. The bunker is probably going to be a nightmare.
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Post by Roger on Jun 6, 2020 22:23:22 GMT
I think you are all getting a bit too absorbed in all this without seeing the bigger picture. GWR locos were generally badly painted in 'A' shop. There was no dedicated paint shop, and all paint was applied by brush. The 15XX class probably came within the period of commercial tins of paint. But gloss black is gloss black. That is what these locos were painted with. There is substantial photographic evidence of this. I've never known of waterslide transfers deteriorate, and, yes, they should best be applied to a gloss paint surface. And I've never used varnish on a miniature loco either. You stir a tin of black gloss enamel to paint a 15XX just as they do on the SVR, and many of us do in our workshops. You don't have to stir up pigments at the bottom of the tin for black gloss, or stir it around at 1000rpm scratching the bottom of the tin; it is black gloss enamel after all. Cheers, Julian Hi Julian, Maybe if paint is applied by brush, there isn't an issue with pigment settling out. Bob was in the business of manufacturing paint, so I wouldn't dismiss his advice unless I knew better, which I certainly don't. It may be that for every 30 or 100 tins, you'll get one that has settled enough to be a problem. Unless you're in the business of making the stuff, I don't think you would ever know if it was a problem or not. Since there's an easy way to follow best practice, it makes sense for me to do that and avoid those situations where the paint isn't evenly mixed.
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