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    • November 25, 2017 12:24 AM EST
    • The USN is no longer using MEK they are changing their instructions in their manuals to use Methyl Propal Ketone (MPK).

      http://www.eastman.com/Literature_Center/T/TT33.pdf

      http://www.oxea-chemicals.com/fileadmin/user_upload/110503_MEK_Replacement_Tech_Bulletin.pdf

    • November 24, 2017 5:31 PM EST
    • FYI for Californians, MEK readily available in NV, just a quick trip over the boarder and available at most paint and hardware stores.  Minimum size a pint.  Best thing is that you can enjoy a day of skiing or gambling while making this purchase.

    • November 24, 2017 8:57 AM EST
    • Seems this is very good for acrylics.....easy to apply....

       

      https://www.tapplastics.com/product/repair_products/plastic_adhesives/tap_acrylic_cement/130

    • November 24, 2017 3:34 AM EST
    • Ray Dunakin said:

      Sadly, MEK has been banned here in the People's Republic of Kalifornia. I bought a quart can shortly before they stopped selling it. If I had known, I would have bought a gallon. I haven't run out yet but I will eventually so I too am curious as to whether there is a decent substitute. I don't think acetone works very well.

       

       

      Why not LOAD UP  Ray when you visit a state that has not banned it

    • November 23, 2017 6:59 PM EST
    • Thank you Russ for that detailed post. Very helpful info there.  I do a lot of work with acrylics and expanded PVC board in my sign shop job. I use SciGrip 4 for acrylic and it works great for me. For foamed PVC to Foamed PVC I have used the self priming PVC pipe adhesive you can get at the big box stores with good results.  I use Weldon 16 at home for lots of modeling uses with generally good results. Last night I tried bonding Foamed PVC board to Styrene (A coupler mounting pad to a Delton Classic frame) with MEK  and the joint failed after 10 hours or so dry time, Today I re-joined it with Weldon-16 which I have used for the same job before with great results.  I also leaned not to over apply the MEK. I was using it to repair a broken truck mount with a PVC pad and a T-Nut from above. I nearly melted through the frame!

    • November 23, 2017 6:11 PM EST
    • I have used MEK, and acetone, but I also use "Lacqure Thinner", in fact I use it more than anything else, but it contains some of both of the others, I've been told.  We can easily get all of them here in Ottawa...Home Depot, and Crappy Tire carry them.

        Fred Mills

    • November 23, 2017 4:59 PM EST
    • Sadly, MEK has been banned here in the People's Republic of Kalifornia. I bought a quart can shortly before they stopped selling it. If I had known, I would have bought a gallon. I haven't run out yet but I will eventually so I too am curious as to whether there is a decent substitute. I don't think acetone works very well.

    • November 23, 2017 2:19 PM EST
    • I have been using Weld-On 16 primarily because I've always had difficulty finding MEK in anything less than a gallon can (and even that was difficult). I was at my local Ace Hardware and I found "Painter's Solvent," which says on the can that it replaces MEK. Has anyone ever seen or tried it before? Thoughts?

    • November 23, 2017 1:48 PM EST
    • Big thanks Russell. I've been using SG #4, but was planning on trying to glue acrylic shingles with MEK. So thanks for the averted mess! I'll get more #4. 

       

      Cliff

       

    • November 23, 2017 1:37 PM EST
    • I've been gluing together different plastics for 37 years now (!) at my job at TAP Plastics. I've seen a lot of really useful solvents disappear here in California as the VOC (Volatile Organic Compound) laws make them illegal. MEK has been the latest added to the list. We used to sell pure MEK by the Gallon and 5 Gallon container, now my customers have to go to Nevada to acquire large quantities of it.

      We use MEK at TAP Plastics to solvent weld together ABS and High Impact Styrene (Polystyrene). Nothing works better. If you need some body to the glue, I recommend using SCIGrip Weld-On 16 . The Weld-On 16 contains MEK along with other solvents along with Acrylic Monomer to thicken it. Here is the SDS... TAP Plastics also sells SCIgrip Weld-on 2354 for ABS and Styrene. It is mostly MEK and it is what we have to use in the shop now... Here is the SDS ... Of course, I use MEK at home.

      For the expanded PVC (Sintra, Komatex or Celtec) and other PVC sheets we use Weld-On 2007.It is a solvent only formula with no thickeners added so it flows really well.

      For Acrylic Plastic we use Weld-On #4, #3 and the TAP Acrylic Cement.   #4 is a little slower in evaporation and thus has more time to melt the acrylic and make a strong bond. We use this the most, especially on aquariums and thicker sheets. The TAP brand and the #3 are the same product but we are able to sell it at a lower price since it carries our name. These are the Applicators we use to apply these water thin solvents...

      Jon posted this link.." http://nerfhaven.com/forums/topic/18527-intro-to-solvent-welding-plastic/ " and in general it is correct. I would never use MEK or Acetone to glue Acrylic... I've mixed up bottles in the past in our shop and I can tell you accidentally using MEK on acrylic doesn't work. The joints fail quite easily... Also, I've never found a solvent that will bond HDPE, UHMW, LDPE, Polypropylene or Delrin. Heck, the solvent applicators mentioned earlier are made of solvent resistant polyethylene! I also found it interesting that he says Methylene Dichloride is banned in Europe while Ethylene Dichloride is not... The opposite occurs here.

      Russ Miller

      Past BAGRS President

      NGRC 2016 Chairman

      TAP Plastics Manager

    • November 24, 2017 9:38 PM EST
    • My next project is to attempt to make a diesel loco based loosely on an RS-3 using a Little Critter as the short hood and cabin and trying to make a long hood and extend the deck. 

      The railways in my state of New South Wales (NSW) had a version of an RS-3 (see picture) with a different shaped cabin.

      I have a motor block that I can use and I plan to clone the side bars.
      I would like an RS-3 but to get one to Aust costs more in postage than what I could buy one for, last time I looked $450 US for the loco and $500 for postage and handling, so this is my solution.

      Might take a while but who knows, I think my biggest problem will be shaping the long hood, the rest should be easy (famous last words??).

    • November 24, 2017 9:31 PM EST
    • Last one I call it "Frankenwagon" as it is mage from bits of junk (or treasure if you so desire) I had lying around the shed that was heading for the rubbish bin.

      The thinking behind this is (well was I thinking) something along the lines of a power wagon that could be shunted onto a siding at a logging camp to provide electricity for the huts.
      The managing director being built for comfort and not for speed with a passion for Glamping ordered it built as he did not want to be using oil lamps when that new fangled electrickery technology was available.

       

       

    • November 24, 2017 9:23 PM EST
    • Second lot
      The planking on the flat car is made from paddle pop/coffee stirrer sticks glued on and stained with acrylic artist paints diluted with methylated spirit/de-natured alcohol.
      In the first pic you can make out the pieces of flat steel that is used to prevent warping of the MDF deck and adds weight, all my wagons are on the same chassis design 
      The pipes are 25mm PVC electrical conduit with the flanges cut from an old plastic sign, the rests are just pieces of timber with grooves (made with a round file) to stop the pipes from rolling sideways.
      The chains on both are from the cheap/DIY jewelry section of a $2 shop, in the gondola they are attached by hook and loop dressmaking accessories and rivets that I bought from a bloke in Sri Lanka (goes by the name of Pasidump on ebay) who make G Scale kits of short flat cars, plus link and pin couplers similar to LGB.

       

    • November 24, 2017 9:15 PM EST
    • The last of my "therapy wagons" are now complete, they were originally started to give me something to do while recovering from hip replacement surgery but took a little longer to finish than I planned, there are 6 wagons in all to go behind my Bachmann "Connie".

      First one is a gondola with scrap vehicles going to recycle yard, I found the vehicles in a market stall amongst some old toys total cost 50c, the dents are the result of the use of a blow torch and some shaping.

      I varnished the wood instead of painting it because SWMBO said it would be a shame to cover it up, the "bolts" are brass dressmaking pins blackened with a felt tip pen.

    • November 23, 2017 1:34 AM EST
    • Now on the roof, draw a line 1/8" back from the front edge.

      Run some 3/64" angle along this line. End it just before the curve at the outside edges of the roof. Keep the angled corner towards the rear.

      Now for the bell mount start with two pieces of .02" styrene 1/2" squares. Mark them up and cut them as shown below.

      Cut a 1/2" piece of 1/8 x 1/8" styrene. Drill a 1/16" hole 1/8" from the front, and notch the rear slightly so that it will sit nicely against the bend between the front windows. Insert the bell, and glue on the sides.

      Mount it up against the top curve of the cab.

      Cut two 1/2" pieces of .01 x .04" styrene.

      Glue one on each side of the bell assembly.

      Cut four small pieces of .05" round styrene and mount around the top of the bell as shown. I also added a small piece of stripped telephone wire for the air line. I drilled a small hole for the rear and used epoxy to attach the front.

    • November 23, 2017 12:51 AM EST
    • Run some 3/64" angle along the rear of the nose.

      For the rear window frames, start with two pieces of .02" styrene cut 5/16 x 15/16". Mark a 1/16" frame around the edges. Drill 1/8" holes in the inner four corners and then cut out between the holes. Sand the outer corners to match the inner curves.

      Center these on the rear windows and secure them. Make sure they do not interfere when the cab is placed against the tapered section.

      For the front window frames, cut a .02" piece of styrene 3 1/2 x 7/8". Divide it up into four 7/8" squares. Mark lines 5/16" between the windows at the top. Mark 1/16" frames and mark the inner corners to be drilled at 1/8".

      Drill the inner corners.

      Cut out between the drill holes.

      Separate the window frames.

      Cut off the excess at the bottoms. File the outer corners to match up to the inner curves. (not shown)

      Tape them into place and once you are happy with the spacing, glue them in.

      Once they are dry, you can clean them up as required with a file.

    • November 22, 2017 8:19 PM EST
    • The tail end hatch mounts centered and 1/4" in from the end. Facing the tail end, the hinge is towards the right.

      For the front hatches, draw a line on the nose from the back edge of the side corner curve up to the bend in the nose hood.

      The front hatches mount with the hinge towards the center of the nose. Looking at the hatch from above, line it up with the bend in the nose hood, and the line you drew. From above, it should stay within these two lines.

    • November 22, 2017 7:49 PM EST
    • Sand hatches. We're going to build three sand hatches. Two are for the nose, and one is for the tail.

      Front - two pieces of .03" styrene cut 1/2 x 5/16" and two pieces of 1/16" styrene cut 7/16 x 1/4".

      Rear - one piece of 1/16" styrene cut 1/2 x 5/16" and one 1/16" piece cut 7/16 x 1/4".

      Center and glue the smaller pieces on the larger ones. The lid of the tail end is thicker.

      Cut three pieces of .015 x .1" styrene 1/16".

      Mark a 1/8" section centered on the short side of the tail lid and centered on the long side of the front lids.

      Glue the little pieces you cut overhanging one side by half as shown.

      Cut six pieces of .015 x .1" styrene 3/16", and mark a line 1/16" from one end.

      Cut about 2/3 out of the 1/8" side.

      Mount these on the opposite side of the small tab along the lines you drew.

      Cut three pieces of .025" rod 1/8" long.

      Mount these as shown below at the base of the two thin pieces to represent hinges. File the top outside corners of the thin pieces to a slight curve. Leave the bottom squared.

    • November 22, 2017 6:58 PM EST
    • Now for some detail. Cut eight pieces of .025" rod 1/8" long. Four will be for hinges, and four will be for wing screws.

      Cut four pieces of .03 x .1" styrene into squares.

      File one side into a nice curve.

      Cut four more pieces 1/16" long and mount them on the squared side.

      The hinge pieces mount on top 1/8" in from the edges. The above pieces mount on the bottom 1/8" in from the edges with the 1/16" piece down, larger curved piece up with the curve at the bottom. Then mount a piece of rod on top to represent the wing screws. Try to mount them at different angles. (painting note - these wing screws are unpainted brass)

    • November 22, 2017 6:17 PM EST
    • Thanks Guys

       

      Now it's time for the number boards. Start with some .02" styrene cut 7/16 x 15/16".

      Mark the frame 1/8" from the top, 1/16" from the bottom and 3/16" from the sides. The corners will be drilled at 1/8" so mark the 1/16" centers.

      Drill guide holes and then work up to 1/8"

      Cut out between the drilled holes.

      Cut some .03 x .1" styrene for the frame. Cut two pieces 15/16" and two pieces 3/8".

      Glue the top and bottom pieces to the back, flush with the edges.

      Once the top and bottom are dry, glue the sides into place. You may have to sand them a little to get a good fit.

      Cut a couple of base plates 7/8" x 3/8" out of 1/16" styrene. Sand them so that they fit nicely into the rear of the number board frames. If they are too tight, you'll pop the side frames.

      The number boards mount 1 1/2" from the bottom of the nose, 1/16" from the outer edge, and 1 3/16" from the center of the nose. Mount the base pieces centered within these marks, leaving room for the .03" frames. The right hand number board sits snug against the door hinge. Make sure you have enough space for the .03" frame to slide into place.