Egilman

Well, I guess I'm going to have to stop reading about General sherman to watch a general sherman..... pulling up the ol' three legged stool.....

The Garland ventilator is an example of the Coanda Effect in action, which produces a greater velocity in an airflow when the flow is moving along a smooth surface. When coupled with a large intake plenum (ducted fan principle) it actually increases the amount of air moved and the resulting flow increase causes the vented air to circulate farther than an otherwise simple duct would thereby increasing the ventilation effect.... At the time Garland designed his ventilator, the Coanda effect couldn't be explained by the engineers but it worked. It was used on a great many devices like the big oval ship ventilators. In 1909 Henri Coanda wrote the definitive paper on this effect in fluids, (air is considered a fluid in aerodynamics) and used what he learned to build an airplane which many describe as the first jet in 1910. (I don't know about that, but it was the first ducted fan) The Coanda Effect is similar to the Venturi Effect of increased volume flow through a tapered tube with a great many varied applications a lot of our mechanical devices require it to operate..... An example of practical engineering from observed phenomena without completely understanding the science behind it... It was patented in 1905, but didn't come into widespread use until the 1910-1920's

Good deal my friend, I've enjoyed your journeys, (in the short time I've been here) and am looking forward to more...

Thank you Dennis, going to get back to her real soon....

I agree with Jack here, I have the same problem, most of it is figuring out the dividing line between the reality we remember/investigate/research and what is possible to make in the current mediums in use... when I started the M8, I wanted to do all the details, right down to the bolt heads, the generator with the caps and chains attaching them.... My mind said I can, but the physical materials to make such tiny parts does not exist... We build representations that in our minds eye look real.... we cannot allow ourselves to get caught up in the "it's not going to be good enough" which grows into the "I'm not capable enough" meme that we all tell ourselves..... From what I'm seeing, your Huey is coming out great, probably better than I could do at this point.... don't fall into the trap of saying I can't match what others are doing, cause believe me, no one can do what you are doing either... Go for it brother don't allow doubt to stop you.....

This build was the second build back from a 30 year hiatus from building, (the first was an RPM FT-17 cannon version) I thought as you did that my skills were going to be too rusty for anything but my own edification... What I have really found, is with the patience and wisdom of age, I've actually gotten better.... It's like riding a bike, you never forget and the absolute enthusiasm of youth is moderated with the age..... And the results show it..... Thirty years ago this would not have turned out as well as it did..... (and I still see rome for improvement) My opinion, in this field of endeavour, age is a bonus that adds to the end result.... Over the last couple of months I have learned this, and I personally have no doubts you can do it at least as good as before and much more likely better than you ever have... My first kit in over 30 years...... If I can do that after a 3 decade layover, I'm sure you could too.... Go for it brother, you will not regret it....

Thank you Craig, I'm sorta partial to the subject myself, intend to do more artillery and prime movers in the future... (including the little know US Army "88") I lot of great scratchbuilding goes on here in this fora, I hope my contribution added to the overall knowledgebase... Thank you for the compliment it means a lot...

Thanks Ken, I don't know about perfect, but it does look the part.... I guess that is what we are after.... Thank you..

Thanks Jack, they both are one of those things I wanted to do as a young'un but didn't have the time nor resources.... I hope some of it helps you in rescuing yours.....

Thanks Lou, I suspect that if you built one today with the knowledge and experience you have now it would turn out just as well if not better.... I'm happy you enjoyed it....

Thanks Ed, I'm very glad you liked it....

Last construction update..... Finished the Generator and mounted it. Manufacturing the lifting lugs proved to be a bit fiddly but I got it done. Lifting Lugs constructed and attached to the clevises and cables.... Preparing the attachment points.... Putty fills the holes on the ends of the half-round skid bumpers.... Sanded flush and Lugs mounted.... Generator mounted to the lift and raised halfway to full height..... Opposite side view...... Fully loaded position, the fit appears to be perfect.... Painting off the corners and touch ups.... Another test fit.... Cables painted off gunmetal, the Cables, although when manufactured were painted OD Green, in a very short time with moderate usage the paint flaked off leaving the oiled cables exposed. the cables were oiled to prevent corrosion.... Left side profile with the Generator in it's final position and the cables superglued to their lifting hooks....... Left Front view..... Right Rear View...... Right Front View.... Rear view with the generator permanently in place..... (and one touch-up still to do) Mount the drivers door mirror, body hoops and the antenna and she is done.... Complete...... With its M-51 Skysweeper hooked up..... I decided not to load up the body with details, I could have gone another couple of weeks building and adding stuff. This would make an excellent diorama subject not often built... I added a tarp, folded in its storage place above the ready ammo lockers, a simple piece of napkin trimmed to appropriate size, rolled and folded to fit it's space, then drybrushed in field drab with olive drab highlights.... An issue vehicle would have it's tarps... And no the M-51 didn't travel with ammo in the autoloader, it's just that sitting on the shelf for 4 months has caused the rotation mechanism of the ammo holder to freeze up. I couldn't rotate them to remove the shells. So I left it this way cause I didn't want to break it just to take a pic as unloaded..... FINISHED! Thanks for the comments and likes, this was my first major project in a long time and I hope that you enjoyed it.... (even the wife was impressed) EG

Thank you Mark Almost finished, thanks everyone for following along....

Well we are now going to finish off the M-18 Generator, it's all in the details.... It's pretty much laid out in the pictures above what the details are, most of them are fairly simple and can be reproduced in similie with tidbits from the parts box except the very distinctive louvers, the three power receptacles, the lifting lugs on each corner and the radiused bullnoses on both ends of the frame bottom.... We will start with the Louvers very small and difficult to reproduce. Fortunately, Archer Fine Transfers has come to the rescue..... They make a set of very fine cast resin louvers on decal paper. now these are "O" gauge railroad scale which translates into 1/48th scale for those of us not familiar with rail scale.... Problem is I'm working in 1/35th scale, an oddball metric scale designed to fit plastic models around little electric motors to make build your own toys.... so what we have to do is figure out how long a louver we need and see if something will match the length..... Well my trusty scale calculator told me from my scaled drawings that I needed louvers that were approximately .125 inch long and I would need twelve of them in each of eight vertical columns on both sides of the generator housing.... the vertical column measures .75 inch. In the picture above the shortest louvers on the sheet measure exactly .125 inch and at 1/48th scale that makes a pretty good representation of a 6" louver..... The louvers I need are somewhere between 4-5 inches long so I settled on 4.5 inches long which in 1/35th scale equals .128 inch.... but, in the vertical space allocated for louvers, I cannot fit 12 louvers I can only fit 8.... so we are looking at impression rather than absolute accuracy... the louvers are there and in certain light conditions are very apparent and would be missed by anyone familiar with the equipment.... So, lets see how we did.... This is the left side, sorry it's a little blurry... (they apply and lay down just like decals cut dip in water and when loose, slide into position on a glossy surface, and let dry) The right side in a much better pic.... Now I know they look like black lines, the real effect comes when you paint over them..... Another blurry pic, (I've got to get a better camera) the receptacles mounted on the left side, these are the electrical connections for the gun and director.... This pic of the right side rear shows the frame bullnose, fuel filler and gauge and the radiator cap the hinge detail added above the side doors.... we are now ready for painting...... First coat of paint, left side, given the light angle the louvers are hard to see, they are there but almost invisible.. (which was expected given the color and light conditions) Right side, again the louvers are there, a bit easier to pick out here but still almost invisible... which is what you would see in real life in similar light conditions. Subtle, but effective and very scale appearing in my opinion..... Up on the mount in loaded position the slight light change casts a bit more definition to them. I think they are spot on as far as effect.... but that is just my opinion.... Next up, lifting lugs, mounting to the tractor and finishing off.... EG

I thought about that Ken, but I really have never had good results with SG on polystyrene as the primary glue, I can never seem to get it to hold.... what I did was put .020 panels between the formers high enough to lay under the hood/doors giving a large firm gluing area. Then the hood/doors was pulled down over the formers real tight and clamped, letting the tubes hold the shape while the glue set between the flat panels. when it was dry, I put a dab of SG on the peaks of the hood at both ends so the end panels wouldn't shift.... It's remarkably strong.....

After careful consideration I settled on a way to attach the hood to the frame without the warping and distortion..... The main issue was not enough support from the formers for the thin sheet plastic of the hood. So I cut down the center profile to just below the door hinge line. I then added tubular rods on the three curves, both shoulders and the peak, then sanded the joins smooth. This adds support for the full length of the hood and doesn't need glue except a few tiny drops along the edges..... Below along the frame I added some .040 plastic sheet to reinforce the center support and give thicker plastic where the side panels and doors would wind up, a solid gluing surface..... Lets see how it turned out...... Back to square one, figuring a new way to mount the hood. I need to use .010 for the hood as it gives the proper scale appearance, but have to figure a way to edge glue it without depending on the formers to shape it. Beefed up frame.... Hood and side doors prebent. I lengthened the hood to incorporate the side doors into one piece, this allowed the side doors to keep the outer edges of the hood from bowing outwards. Since the hood and doors lay on the same plane in real life this is the elegant solution for the plastic tension that was causing the hood to warp.... Hood and Doors folded along the shoulder line, I'm using my container of paint stirrers to provide the weight needed for the plastic to stay in shape and settle into it's folds without creasing the corner.... The folded hood ready for installation..... The hood installed and the door separation groove cut to just below the hinge line. Right front view, completely glued and no distortions/warping.... Left Rear view, you can clearly see the hood end overhang without any deformation or warping.... Since we now have the M-18's basic shape complete it's time for its first test of fit sitting in its position on the rear platform of the M-8 HST..... And the opposite right rear view showing it appears in scale and fits in its spot comfortably... Now, continuing on to the details...... EG

That cause we all knew that the sharp edge went forward so it cleanly cut thru the air.... (even that young we understood that the pointy end goes forward)

As mentioned before I was able to obtain the US Army Tech Manuals for this particular piece of equipment, it is a 35Kw continuous duty alternating current generator. Usually it was supplied to the antiaircraft units using the 90 & 120 mm antiaircraft guns during WWII/Korea and postwar to the M-51 Skysweeper battalions. Capable of supplying the power requirements of an entire battery of guns, (4) including their directors. Additional units were supplied to support the radar companies that were attached to the AA battalions. Little known fact, all of our heavy antiaircraft weaponry from about mid 1942 on, has been power laid and radar guided, accompanied by the VX fuse, they became the deadliest AA guns the world had ever seen. This was the power unit that made it all happen for the US Army. This is my attempt to recreate in 1/35th scale one of these absolutely essential pieces of equipment. Time to hack some plastic...... Basic box parts used as a frame. the original frame was built of steel channel and plate, for this a simple box will do. Base glued up, I'm using .040 sheet styrene to make the foundations and basic profile shapes. Tabs added as stiffeners and locators for the interior bulkheads Rough cut radiator in place along with the end bulkhead and sidewalls for the fuel tank compartment. Forward bulkhead glued behind the radiator, core support sections added around the base of the radiator, two more bulkheads in the middle to support the side panels to go. Fuel Tank cover in place cut from .010 sheet.... Radiator built up with doors and side supports out of .020 sheet.... Once the radiator was added the whole thing started to develop a narrowing towards the top, so I added a strut to push the top opening wider and back into vertical alignment. Center support build up out of .020, this is needed cause the side panels are split fore and aft forming the two access doors and side covers. Forming the hood out of .010 sheet. (wrapping it around a file handle to set the curve) Hood glued on the left side. Gluing the right side of the hood around the profiles. Beginning to take shape, but note the wrinkle that has developed in the middle of the hood. Sorry for the blurry pic. But even such, you can easily see that with the right edge glued down around the side curve, a major issue shows up here, the glue (MEK) is too strong for the .010 sheet styrene and has caused warping and deformation of the sheet on the ends. Also note the edges of the hood over the openings, the tension in the sheet has caused the hood to bow outwards. This isn't going to work. I need to support the hood on the ends and middle where it contacts the formers also over the openings so it doesn't warp....... I need to rethink how I'm going to form the hood..... It needs support all along the top edge and an alternative way of gluing it down so the glue doesn't destroy the edges..... Next up, the solution...... EG

WE all have our glue smeared messes in our backgrounds.... part and parcel of learning the art... just like not being able to color between the lines in kindergarten.... the more you try, the better you get..... Michaelangeo didn't carve "David" his first time out..... Thank you for the comment....

Yes, the extant case was in baltimore where a 7 yr old ws suspended for chewing his poptart into a gun shape and was suspended on the school districts "zero" tolerance for guns policy.... shortly afterwards a child ws bounced here in washington and in florida for the exact same thing citing the same policy... Later the courts, on appeal upheld the suspension which is now permanently on the boys school record.... Here in Washington it is ok for an elementary child to carry a 6-9" ceremonial dagger in school as a religious object (sikh religious artifact) but can't point his finger and go "Bang Bang" https://2ahawaii.com/index.php?topic=16905.0 (unfortunately the links to the original media story are dead)

Yeah, it's gotten to the point if you take bites into your poptart in the wrong places and sequence in the school lunchroom, you can be booted out of school for firearms violations..... (at least in certain school districts here in Washington State...... (true story)

That was one of the first things President Reagan did, start the process of upgrading all the almost worn out WWII/Korean war equipment that the military was making due with...... it's one of the things you CAN credit Bill Clinton with is that he continued the process.....

They built a lot of M-18's they were used throughout the '60's well into the '70's before they were replaced....... They remained substitute standard into the '90's....

Well it's time to start the process of accurately modeling an M-18 Generator... first step gathering images, overall images and detail images.... All scale scratch building starts with preparation..... This is what I need to create, it measures Length, over-all ................................... 100 1/2 in. in 1/35th Scale ...... 2.87 in. Width, over-all ..................................... 41 5/8 in. ...... 1.189 in. Height, over-all .................................... 56 5/8 in. ...... 1.618 in. First thing to do is get an accurate profile so I will need two sides and a vertical.... The images above I've posted before they definitely give an indication of the details required and come from the US Army Tech manuals for the unit.... These two images come from the US Army Tech manual for the M-7 Generator set, the M-7 is just an earlier model of the same capacity and size just not s refined.... It's good to get a design history so one can see what the engineering principles were for the particular piece of equipment. These two generators were used interchangeably during WWII, but the M-7 was phased out by the Korean War in favor of the M-18. Although good for details, these images do not give me what I really need, which is profile drawings/images..... for that we have to turn to the operator's manual TM 9-617.... Page 26 and 51 of the operator's manual gives exactly what is needed, direct face on profiles.... The first step we need to do is clean, correct their sizes and scale them... For example look at the radiator and core support image above, it is stretched vertically.... the fan opening need to be a circle.....Ve I prefer to use gimp for image processing, the vertical profile is now corrected and scaled as well. It was squeezed narrower that it really was. This was easy to fix in Gimp by scaling it out wider till the fan opening in the shroud was a true circle.... M-18 left & right side cleaned, cropped and scaled. The fan shroud pic above also has the radiator core support so it was an easy job to scale it to size matching it to the left profile in height from the core support up to the radiator cap, this also gives you an accurate width once the vertical stretch was removed. Frame image cleaned and scaled. Once all this is done we can assemble and print out a scaled construction guide...... This image shows all necessary views needed to build a scaled replica..... Next part, cutting plastic.....

You never know with the Department of Homeland Security nowadays......