robdebie

Don't make this a battle of who's right. I share my experiences, you share yours. Rob

My experience is the opposite: my CA glues do lose their adhesive power after (say) six months. It's usually the first signal the glue is getting too old. The second signal would be that it starts to form strings. I write the opening date on each container, and simply replace them after 6+ months. Almost every time I replace a container, I note that the glue works much better. The cost is minor. Rob

I would say six months, for a container that is opened regularly. Rob

Good point, you need a buck / master / plug. And that means more work. Here are two of mine. The first is for an A-12 Avenger, the resulting canopies are shown above. The second is for a Bede 5 homebuilt. I want to pull a negative mold from this master, because a piece vacformed straight over this master would be oversized. The model is so small that an oversized canopy would not work. I'm busy experimenting to laminate a glassfiber shell over it. Rob

I bought 0.5 and 1.0 mm (0.020" & 0.040"), and use both. It depends mostly on the size of the object to be vacformed, and the 'feel' of the vacformed part. Rob

PET-G will develop steam bubbles if heated too long. Here are samples with and without. Made on the very dental machine you're asking about. Rob

We bought one with a small group from our club, and have it's been doing rounds since then. The thing is clunky, but I would say it works well enough. The chrome ball knob needs to be in exactly one position, in my experience - I think the photo shows the correct one. And I never use the (what I think is) ball bearing holder, the first metal-colored thing from the bottom. Leaving it off gives you a flatter and slighter larger area to work with. Rob

Thanks all for the replies so far. A small update: I planned to do some experiments, with bent / folded plastic card strips, but I ran out of Zap thin CA, my prime suspect. The cracks in the tank trailer are repaired, and no new problems have surfaced. Rob

I had noted before that small polystyrene strips would crack severely if I bent them first, then glued them on a model's curved surface. Say a 1 x 1 mm strip would break up in 2 to 3 mm segements, and the segments themselves would also show many more tiny cracks. It difficult to photograph, so I can't show it (yet). Yesterday I made an extension for a 1/25 scale tank trailer (MPC / Lindberg). I first extended the top side of the tank forward with five plastic card 'stringers'. Then I cut a piece of 1 mm plastic card to the required (complex) shape, then pre-curved (rolled) it on the edge of a table. The edges were glued together to form a tube / pipe, and I installed an elliptical bulkhead internally. Lastly added the curved front face of the tank, as an oversize piece, glued on with Zap thin CA, purple label. And then it happened: severe cracking of the bent plastic card - something I had never experienced before. Is there anyone who understands what's going on here? I have a feeling it's not happening with all CA glues that I use, I should do more experiments. Rob

You are right: I meant to say the atomization principle is crude, not the manufacturing or finish. Rob

I forgot to point out that your 'new expensive airbrush' is likely a large part of the problem. It atomizes the paint too fine, creating a very large total surface area of the atomized paint. That in turn causes a lot of thinner evaporation in the short distance between the airbrush and the model. The paint arrives thicker (more viscous) on the model that it was before you added thinner, and is so thick it cannot flow out to a smooth paint layer. Hence the orange peel. One solution is a cruder cheaper airbrush, that atomizes coarsely - see the 'Donn Yost' technique as mentioned in my previous reply. Rob

Yet another route to try: the 'Donn Yost' paint technique, as demonstrated here: https://www.youtube.com/watch?v=lCKZ_fo4eW0 I had 30 years of problems like you describe, but this really works well, with all of the brands of enamel paint that I have in stock. No polishing, no clearcoat, simply smooooth paint ? The Paasche H, or a similar *crude* airbrush, is the key ingredient I believe. You need to crank it wide open for the final coat. Rob

I made a Blues Brothers Pinto Wagon from a glue bomb of the 46 year old MPC kit: Rob

Thanks! Now I can see the models you offer for the first time! Rob

I have exactly the same experience. I always use Future under the decals, although I recently started using Tamiya decal adhesive. The edges of the clear film curl up a bit, and need coaxing down, usually with a little bit more Future. But other than that, I would give them the same note as the average silkscreen printed kit decal sheet. I'm happy with them. Here's another model done with SpotModel decals, the 1976 F-16 model by Revell. Rob

THe good news is that a newly made custom decal sheet will look 10x better than the original decal sheet, I'm sure of that! Here's a sheet that I designed recently, and was printed by Spotmodel: I do custom decal assignments too, a few every year. Here's a page about that service: https://robdebie.home.xs4all.nl/models/customdecals.htm It has six examples of decal projects, that hopefully make clear why drawing decal art takes considerable time. It's like Dave Van asked: "Q is are you willing to pay for art and printing??".. Rob

Chris (who started this thread), could you check the power of the fan? It's a simple indicator of the air flow. In my current paint booth, I use a ~75 Watt blower from a kitchen hood, and it's marginal if I'm using my air brush wide open, like in the 'Donn Yost' technique. I have a 150 Watt blower waiting to be converted into a paint booth. Now that's maybe a tad too much, but better too much than too little. Rob

Peteski, that sounds like how I learned how an Alps printer worked from you and others, some 20 years ago ? One more comment is that the 'sphere and cone' markers are a bit misleading, the real supports are way bigger. In this case the real ones overlap the lower side and rear side of the louvers. Please note that I'm very much a beginner with this, I started doing the supports maybe a month ago, and applied the new knowlegde to maybe 10 parts. I don't have a printer myself, a club member does the printing for me. But having control over the supports is a great plus, it improved the results a lot. And it saves the club member some time too. Rob

I don't have total control over the supports. In the software I'm using (PrusaSlicer), you put a small sphere where you want a support, and it has a cone that defines the direction of the support. But the rest is up to the software, and it sometimes has a mind of its own. Rob

Peteski, that is an excellent question. I had to learn a thing or two on the subject of supports before the part came out right (out of the printer of a club member). I added the supports manually, because automatically generated supports did not yield good prints. It's my own interpretation of what was required, and I went for 'safe' regarding the thin louvers, giving them 10+ supports each. The overall result was a true forrest of supports. But that's mainly because this a strange part to print. The part now printed near perfect, but it was difficult to get all the supports off. I worked my way down from the grille's top, and maybe spent half an hour. I had positioned the supports on the louvers such that I could get to them with a razor blade saw from the front (as you see in the picture). I would then snip away the supports from the rear side. Still I broke three louvers, but the breaks are so brittle that they fit perfectly back together, and could be glued invisibly with thin CA. Rob

Here's a follow-up on the 'needle nose' conversion. It took a few attempts to get the grille printed correctly. The first parts shown on page 1 had many problems. The next print is shown on the left of the photo below. The louvers were made 0.45 mm thick instead of 0.3 mm, and still look thin enough to my eye. Each louver had about eight print supports. But I forgot to add supports to the frame above the louvers, so that came out deformed. Another problem that kept coming back were 'dog ears' at the bottom of each printed part. The next print was perfect! I added extra supports at the 'dog ear' corners, and that solved the problem 95%. A bit of sanding solved the remaining 5%. That part of the conversion is done, next is the hood. I will do a 3D design of that part too. Rob

Here's a great webpage on the subject: https://modelpaint.tripod.com/booth2.htm Rob

Simply judging from the fan's power, it won't be strong enough. In my current paint booth, I use a ~75 Watt blower from a kitchen hood, and it's marginal. I have a 150 Watt blower waiting to be converted into a paint booth. I too use (acrylic) lacquers, and you really need a good paint booth for those. Another thing is the ducting. The flow resistance it creates is expressed as 'back pressure' and reduces the flow. Search on 'blower back pressure graph' or similar to see what I mean. Using OSHA rules for paint booths, plus the dimensions of your booth, you can calculate the required flow. Rob

Not a direct answer to your question, but maybe of help anyway. Last year I built the Blues Brothers Illinois nazis' car, and posed it on a fictitious shop display: I put a lot of work in the nose section, and can show more photos if needed. Rob

Here's a great build report of the Lotus-Ford on another forum: https://forum.f1m.com/viewtopic.php?t=33637 I would try to replace the thick glass with a vacform piece. Rob