I just uploaded and reserved space for a couple of parts to be made by Print-a-Part. They are for a 1:20.3 small trussed beam bridge featuring a Phoenix riveted segmental round post. The parts were complex enough to give PaP a try.
I created them in TurboCAD deluxe, saved them as a Collada (.dae) file. I used MeshLab to test and convert them into the .stl file for stereolithography that PaP requires. The renderings below are via MeshLab.
I found the PaP website to be informative and very easy to use. My files uploaded perfectly with no errors. The reservation system is clear and simple. Their capacity was full for the next couple of days so I had to select Economy. They will ship Wednesday.
I am going to make a two-part mold for them so I can cast multitudes. I am planning an article on the whole bridge. Meanwhile, I'll post photos of the cstings when they arrive.
This is a very exciting opportunity for me. Thanks to all here who have researched and communicated about stereolithography for the common man.
John
Cool. I look forward to your results.
Marc
Me too!
I received my parts Friday. I took a couple of quick photos so you can see the results. I am quite pleased with them. I expected the print lines based on all the comments here. A little sanding and they will be ready. It was quite exciting to something that existed only as a virtual drawing come in a box to the house. Plus I can trust it is accurate, much more than I could have done it with hand tools.
Next I will make the Phoenix column tube with the riveted flanges, then assemble the these end castings.
After that I will make a mold box, pour some rubber and make castings. I'll post as I go.
John
PS Russ, the photos will improve as I get used to my new used DSLR camera and how it works with my old lenses.
Congrats! Very cool. Those would have taken a lot of work to scratch accurately...even with time spent sanding priming and surfacing, I think you still come out well ahead.
I look forward to more posts as you progress.
Marc
Nice photos and excellent parts. This 3-D printing concept already seems to be starting to pay dividends. -- Russ
Fabulous! Thanks for sharing.
John -- Since you're planning on making "multitudes" (if I remember for a possible commercial venture), why not try the other vendor and see if they don't come out in ready to cast condition?
Just a thought. I'm going to try that myself soon with some C&S brake components.
Thanks fellers. It is a very exciting concept.
I've been looking through a few eastern logging books and am now interested in recreating a log loader with the riveted boom, gears, drums, engine and boiler. Creating masters is an art that can be streamlined with techniques such as etching and machining, but both are limited in shape and complexity. This PAP is just wonderful- the tolerances are great and it can make very complex shapes. CAD skills and a good data are the major needs for mastering parts for a Barnhart loader kit. And the assurance of testing the fit via CAD can save lots of time, money and trouble.
Fred, it might be worth trying, but those parts cost $27 plus shipping. Very reasonable considering the technology costs. I don't wish to go too much higher so I'll work with them. Some lines may be due to my inexpensive CAD and me forgetting to increase the number of segments to a curved surface. I'll have to write instructions for myself for the next parts so I remember.
John
I finally made some time to work on the little bridge that I had the PAP parts made for.
The Phoenix columns are tubular posts made from rolled iron segments that are riveted together on flanges. I am using styrene tube for the posts so I needed to make riveted flanges to glue on. I used the rivet tool I made for the 1:48 rivets on my On3 truss kit. The .030" rivets are fine for the small flange rivets in 1:20.3.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FPalecki_rivet_tool_clamped_800-600x354.jpg&hash=40ac0bfc44dda4d6d7d2f15ef705746d368ae4b1)
The tool is aluminum with holes drilled in the top and partial holes drilled to match in the bottom. I use a .030" drill bit with the back end rounded to a rivet shape as an embosser. It is set in the pin vise to the exact exposure needed to create a nice round rivet head in whatever thickness styrene I am using. The styrene is butted against the stop strip and then clamped. I mark the top with pencil lines so I know what spacing I need as I go along and push the tool in.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FPalecki_rivet_tool_open_800-600x386.jpg&hash=aa3511a79f02a12992a2f207cdb5add016642b4d)
I drilled it on a home drill press. Marking the centers by hand was impossible so I used a Micro-Mark etching kit to etch holes in a small sheet of brass. The holes were lined up as closely as my printer allowed, which was just fine.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FPalecki_rivet_strip_example_800-600x305.jpg&hash=2a4b6cf598c507b171724b042ed028e86f058b00)
I can create rivet strips as above or emboss the sides of gussets. I made a space in the middle for inserting longer parts too.
The tool works well. I need to make more variations on spacing and size someday.
Next I'll make a column and post that.
John
I read through that at least three times. That is just .. cool. I'm impressed all to .. heck. :)
Wow....that is a cool tool you made!
If you ever decide to make and sell them (for .018, .020 or .025 ;) ).....put me on the list!
Marc
Jeepers thanks. If I had a lil' table top CNC I could make them up easily. It is a robust tool that has lasted for thousands of rivets. Someday I will make a micrometer adjustment for the embosser depth. That is the only drawback- when the drill breaks (moving to quickly generally) I need to grind a new round end and reset the depth.
John
Clever with excellent results! Most satisfactory. -- Russ
;D ;D ;D ;D ;D
Another tool project for the mill!
-Marty
I wasn't sure where to post this...but hopefully you don't mind it here, as this involves a mfr. using PAP for his parts/kist as well.
This is a link to a post on the MIG forum by David Harper of Hardcorpsmodels.com, re his new LTV tracks and sprockets....that are done by PAP. http://www.migproductionsforums.com/phpBB3/viewtopic.php?f=8&t=8256 (http://www.migproductionsforums.com/phpBB3/viewtopic.php?f=8&t=8256).....david in the past has shown other beautiful and really unique specialy model detailing parts that they sell that are done with 3D printing.
Just thought it would be of interest to illustrate others that sre using this method for their kits/parts.
Marc
Somehow I missed the progress...those parts look good John!
Marc, post anything you want here. It is always interesting- the obsession for accurate modeling is clearly in the military guys too. That track's a lot of PAP money though.
Thanks Chuck and Russ. Marty I can offer hints if you really are going to make them for us..I mean yourself.
Tomorrow I need to glue those rivet strips back-to-back without melting them. Then I need to glue them on edge along a tube to form quadrants. See the photo below of a beam from another bridge.
John
OK I assembled my column. I am very pleased.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FBonding_rivet_strips-600x319.jpg&hash=c78dc8506afc53cc46ec2074d286ee0b97e06168)
I clamped the rivet strips together then applied the Tenax.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FApplying_strips_in_vise-600x438.jpg&hash=ec0893688faca7f40cee6acd2468d5b837cb82af)
I marked the post using the end castings for alignment. Then I held the post in a vise and applied the strips.
(https://www.finescalerr.com/smf/proxy.php?request=http%3A%2F%2Fwww.jpstructures.com%2Fsitebuilder%2Fimages%2FPhoenix_beam_master_assy-270x600.jpg&hash=ce3c5a332c71792eb9c15d9a642582d5b26d3927)
I glued on the end castings with AC, cleaned it up and sprayed it with Dullcote to blend in the adhesive marks. The dark stains are from weathering chalk, which I use to highlight scribe marks in styrene.
I don't spray primer because it will come off in the mold and end up sticking to the cast first parts, although it would look better and photograph more easily.
Next I'll show my mold casting boxes and techniques. Stay tuned.
John
Excellent!
Philip
Looking nice...though the right side rivet strip seems to have "issues" at the bottom end ;)...or maybe thats just an optical illusion.
MR
Heck Marc, between 2 in the morning, my new bifocals and the distortion of the Opti-Visor lenses I'm surprised it doesn't look like a barber pole. I think there is some chalk shadowing the joint and maybe the seam on the two rivet strips is uneven. I did sight them all and they looked straight. I'll look again when I get home.
Nonetheless, the PAP parts made it possible to model the beam with its complex castings so I am looking forward to more applications.
John
Nice lookin' rivets, John. The time you spent making the tool and experimenting was well worth it, if you're doing cast iron and steam, you have to master rivets, they can't be fudged.