Building the Formations 1/35 Chaffee (part 1)
I purchased this kit at the 2006 IPMS Nationals. I got everything I needed in the vendors area in one fell swoop. This included the Formations resin conversion, the Italeri donor kit, a vintage On the Mark photo-etch fret and a set of T72E1 Fruilmodel metal tracks. I thought to myself “Hey I can just build this one as is”. I didn’t know squat about the M-24, so how could I possibly go crazy super-detailing an already great resin conversion, anyway?
As you can see, I have already tossed the Italeri box. It was one of those unapealing Testors boxes (with the inner part that has to be slid out). So much stuff for one little tank model! I like to keep all my sub-assemblys in Lean Cuisine trays. I love these things, you can dig around in them to find what you need, are low enough to fit in a closed model box and because they are black your parts show up in them.
Normally, before constructing any model, I would go through all my references and make extensive notes on all the changes and super-detail upgrades I would be making beforehand. These then get turned into punch lists, which make it easier to scratch build. But I digress. In the Chaffee’s case, I skipped this step and dived directly into the build. (Incidentally my comrads in Hobby Club think I’m a nutcase).
Rob Ervin (of Formations) recommemded that I should align the nose of the resin hull top to the plastic hull bottom first, then fix any “gappage” that may appear from the rear. I did this, and as you can see there is quite a lot of “gappage” (almost 1/16 of am inch). While cruising though other online builds, the consensus seemed to be to simply shove a chunk of strip stock in this gap and fill it up. This seemed like a shame to me as the detailing on the back deck is so nice. The next obvious solution seemed to just shorten the hull so the rear deck would mate up, but alas it was not to be. The mounting hole for the rear idler was right on the furthermost edge of the hull sides. If I chopped the hull this idler mount would be compromised. And repositioning the suspension didn’t seem like fun thing to do.
Ultimately, I decided to fit the rear deck inside the plastic hull. This meant shaving off three sides of the resin part (the sides and bottom). This is not entirely accurate, but the fit was awesome, the deck looked great and I didn’t have to mess with the suspension. Its all about the model, right?
Of course, I ended up taking a little too much off the back plate. To fix, I removed a small portion of resin from a pour stub, squared it off and glued it to the edge of the part I wanted to enlarge. Resin super glues extremely well too itself. Once the super glue had set I can reshape the part using a variety of files. In the photo the red line shows what gets chopped off. This method is quick, especialy since you don’t have to mess with any filler.
Here is the rear hull plate in place. To get a nice snug fit, I also needed to remove a little strip of plastic from the hull bottom.
At this point in construction, I remove most of the plastic parts from the sprues. They get organised, by sub-assembly into various Lean Cuisine trays. I have a pair of sprue cutters, but I always seem to nip off a bit of the part when I use them. So I have gotten in the habit of using a flat chisel X-acto blade to chop them off. I have a bunch of Jenga blocks that I can slip under the sprues to use as a support base to cut. Some of these blocks I have cut notches and such into, so I can I can lay the sprue in nice and flat.
Here is a road wheel. The inner portion comes from the donor kit, the outer from the Formations conversion. The Formations part is really the same as the Italeri one, except that the lug nuts are more accurate. The resin has very generous pour stubs, half way around each wheel. These need to be filed off. This is my least favorite part of model building, cleaning up resin parts. The castings started to bug me a little bit, the mold must have bulged open a wee bit during casting, so some of the resin parts were not very true. This bugged me, and I spent a lot time figuring out how I could correct this. Hey, wasn’t I supposed to just “build” this kit?
I had several options to improve the road wheels. My first thought was to remaster one of the Formations parts and recast it. Ultimately I decided against this for a two reasons, 1) I was lazy and 2) castings of things that are supposed to be true and round are almost impossible to get. Resin parts always have a little weirdness. This weirdness becomes most evident in shapes which are supposed to be pefectly flat, round, etcetera. Then I tried to see if I could add the bolt detail to the Italeri outer road wheels, but this turned out to be a dead end. Then I decided to remove the rubber tire portion from the resin wheel on the lathe. My intention was to turn a new outer rubber wheel, then make a new master and cast them (which I said I wasn’t going to do). But then I thought maybe I could just make eveything I needed instead of casting them. There are five pairs of road wheels so this would mean removing the rubber from twenty wheels (ten Italeri ones and ten Formations ones) and fabricating twenty outer rubber tires. I knew I could turn one, but I wasn’t sure how to turn twenty that would be identical (the hard part is those angled sides). Normally, to do this you would grind an angled tool, but again I was too lazy to do this.
But I figured it out. I cut all the rings (i.e., rubber tire parts), first. Then I turned a fixture that the rings would press fit onto. Next, I turned the cutter on the lathe at an angle in order to make the angled side cuts on each tire. I put the first ring (or tire) into the fixture and made the angled cut. Once I had made it I zeroed the position of the cutting tool. Then it was just a matter of pressing each ring onto the fixture, cutting it down to this zeroed position. By flipping the tire both sides were cut. Repeat a zillion times and you have tires. It may seem that this would add a lot of extra time to the whole building process, but I probably net out even in the end. The castings still have to be cleaned up in the first place and because the rubber part are seperate parts I can paint them individualy, so no masking. And they will just look a whole lot better.
Here is the finished road wheel.
Here is the front underside of the hull. It’s a bit warped, but I figured if I glued a brace on the bottom and once it was glued to the hull it would straighten out.
Hmmm. Here it is glued to the hull. As you can see, my hopes were dashed to bits. My ruler shows it it is still noticeably concave.
So I took a deep breath…and started to cut the front off. I scored in a guide and then flipped my X-acto over and scraped instead of cutting. I find this “cuts” better because it doesn’t make a furrow.
Front is off. Broke, too. Darn.
Time to make a new front plate. Save the old one, it will be useful as a guide and has details I can remove to fabricate the new one. I cut a strip of styrene sheet with an ajustable protractor a bit wider than the opening.
The angled part of the opening is trued up on the resin hull peice. Next, the plastic sheet is cut to mate up with this opening. I match the hardest part first (in this case the upside down”v” on top) then I will cut everything else to fit. Note there is a centerline marked on the part, this is extremely helpful to make sure it is centered on the model and symetrical. It also is an aid to position the details.
I put a support inside the hull to pop up the resin part a wee bit…it’s already open, right?
Once the front plate snugs up in place, I hold it on with masking tape and using a very sharp pencil, trace a line around the bottom. The plate is then removed and the lines are a guide to show what gets cut off.
Heres the start of the Trans cover. I use the dimensions from the resin part. All marked and ready to cut the corners off. Its also not a bad idea to check your references at this point, they may have been lazy or just got it wrong. Formations got it right.
Time to cut corners. Again, I use a flat 1/2 inch blade to knock them off. This insures the cuts are arrow straight. Note center line, which can be matched up with the center line on the other plate.
There are a number of recessed hex bolts around the cover. Take a compass and use it to draw a line around the outside. This line will be used as a guide to locate the bolts.
Heres the cover on the model. Lines will be used as a guide to place details. Its good to do a check like this every now and then just to make sure everything looks proportional. Size and thickness looks good.
I need the machine gun hump. I could make one, but its much easier to use the one I already have. Don’t make it, unless you gotta. (Couldn’t I just have used the road wheels?). I cut it out and sanded it flat. Save those parts!
Here it is on the new plate. Again, I draw on numerous guide lines to aid in construction.
Theres a divot in the hull for the MG mounting plate. If I’m going to dig into this part, I need to add a little thickness here. I super glued a chunk of square stock to the bottom. I use super glue for stuff like this becxause the melty tube stuff shrinks when it dries and this can warp your part.
Now take the grinder and… grind. Go slow and let the cutter do the work.
Hump & divot. (Google that!) All I need is a weld seam….
Back to the plate. I know where the holes are going to be. I use a metal probe (as a center punch) to make a starter holes for my drilling. When you use a drill bit to make the holes, the tip will “find” these indentations so as you go they won’t wander off the line.
I jump around a bit when I’m working. This is the bottom of the turret. I decided to get it to fit. While fitting it, I decided that it I should make it key into the hull with the tabs and notches.
This way if someone picks the model up the turret woun’t fall off. And it’s also nice to be able to turn it, especialy for photographing. So here are the “tabs”, two lengths of flat stock. First, I tack them into place and put the turret on. I wiggled the turret, guesstemated the slop, pull the tabs off, sand them. This in effect moves the tabs tighter to the hull. Re-attach. A nice tight, but not too tight, fit. Perfectamundo.
Look at the time! See you next time…
Here’s some of the music I have listened to so far during this build: Star Wars (A New Hope), The Cure (Wish), Ladytron (Softcore Jukebox), Schubert (Symphony No. 7) and the Moody Blues (A Question of Balance).
Part Two will pick up right where part one left off.