Hello all,
I am familiar with the "old" Chris Ward locos and have built quite a number of them - where the loco body has to be burnished.
I have a "new" CWR side tank loco to build but the body is built out of a white 3d printed material. I was wondering if anyone had advice (or could refer me to an article on the forum) as to how to deal with this body - it does not look as though burnishing is required.
Thank you
Robert Berry
Robert,
Could you provide a photo of the body?
Jeff S.
3D printing has improved considerably over the last 18 months or so, and good quality prints do not need as much preparation work as was previously the case.
Many of us have developed our own techniques & here are mine.
1. For a print that has not had a cover of primer, first soak ( in a covered container ) in turpentine substitute for 24 hours. Rinse in cold running water, leave to dry naturally for
48 hours. DO NOT LEAVE ANYWHERE NEAR A HEAT SOURCE OR IN DIRECT SUNLIGHT. Turpentine substitute readily obtainable from Wilko's.
2. Apply a very thin light coat of your preferred primer -- I use Halfords Grey Primer Aerosol. When dry ( use the sniff test , if you can still smell the primer, it aint dry yet).
This first coat of primer will reveal where smoothing to eliminate the layering effect is required. I have found that gentle scraping with the back --- not the cutting edge ---
of a Swann Morton Surgical scalpel blade is best for small areas.
3. Depending on the orientation of the original print, one side will probably need more work than the others.
4. Roofs are often a problem & still suffer from grooving, I deal with this by applying a cellulose based filler "Mr Surfacer 500" ( this is a Japanese product -- there are a number
of UK suppliers -- just do an online search for "Mr Surfacer".
5. The "Mr Surfacer" is applied with a flat brush. Dries in 30 minutes, and can be sanded with fine grade wet & dry paper. Depending on the quality of the print and the depth
of the grooving, this procedure may have to be repeated a number of times. You will also need a tin of cellulose thinner to wash the brush.
6. When satisfied , apply another light coat of primer. Leave to dry thoroughly. at least 36 hours.
7. Model should now be ready for painting, after problems with enamel paints on the very first 3D printed models some years ago ( they took over a week to dry and the finish
was far from perfect -- I now only use acrylic paints on 3D models --- Revell Aqua-Color and Games Workshop Citadel are both good.
8. Painting --- Remember that 3 or 4
very very thin coats are far superior to one thick coat. The first thin coat will look absolutely awful -- you must resist the natural temptation
to apply more paint. Let each coat dry thoroughly before applying the next --- sniff test again!
Hope this helps ,
Garry.
Bob, Use pm facility in "my messages" if you want to contact me if there are further problems.
Picture of CWR loco body as requested
Robert
Robert,
I think Chris got some new printers, a year or two ago now I think. The bodies that came off those were very different from the previous ones and certainly the one I got needed very little polishing before painting it.
Frank
I have just had a look at my Belgian Tram loco, purchased a year ago at Colehill, it doesn't really need any burnishing...
I still need to finish it, but that's another story!
Cheers,
Friso
For your information, Chris and Christine Ward retired from this business last May and the goodwill, and name, have been taken over by Tim Evans of Chase 3D (that's not me!) The website remains the same - http://www.cwrailways.com/, and Tim states he uses "...Stratasys Eden 260v 3D Printing (additive manufacturing) machine."
Tim Sanderson