Welcome to Club SAITO !
11-08-2020, 04:15 PM
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Gee Dave, you are taking to that lathe like a duck to water! Setting up the angle for those internal baffle ports is a real trip eh? Don't have a 220 but I think that Cap44 may. Another possible, make an adapter and run that one on a 120.
My buddy bought lunch today at the ham radio swap so had had money left to burn. I burned a few more pennies worth of Liquid Gold and have some numbers to report.
My old, well worn, early model POS FA-62 was clamped into the iron and flogged with some rather hefty plastic sticks. For direct , relative comparison to the oft overlooked and belittled FA-65, I ran the same propeller trio on the FA-62 that I earlier ran on the FA-65. Fuel from the exact same batch, weather, near identical as well. These props are fairly tough loads for the baby FA-62 but they are the same props I used for the stout cased FA-65.
All props are APC
12.5-6 FA-62 9550 RPM, FA-65 10,850 RPM
13-6 FA-62 9200 RPM, FA-65 10,300 RPM
13-8 FA-62 8350 RPM, FA-65 9700 RPM
This FA-62 is fitted with the extra long, machined from solid bar, velocity stack I have shown here before. I rarely mention on line that that stack does have a positive RPM gain over no stack or even the factory supplied stack. It is precisely sized and aligned to the carb inlet and the bell is an exponential horn rather than a simple, straight horn. It works, but to say so online guffaws and scorn are sure to ensue, so be it. Any body is welcome to visit and see for themselves. I did take advantage of the fresh runs with that stack and decided to pull it off for comparison. I took great care to get an absolute max reading.without the stack. While short stacks typically show little, if any gain, a longer, bell shaped stack, match sized and ALIGNED for smooth, bump-free transition at the joining, can indeed work.
APC 12.5-6 With stack, 9550 RPM, Without stack, 9400 RPM
These props are not the props I typically ran on the FA-62 as it does prefer lighter loads and higher RPM to get into it's realm. Stroke to bore relationships come into play.
Also consider, both engines are running the same carburetor part number IIRC.
Machined, wide, true exponential long stack matched diameter intake.
Gee Dave, you are taking to that lathe like a duck to water! Setting up the angle for those internal baffle ports is a real trip eh? Don't have a 220 but I think that Cap44 may. Another possible, make an adapter and run that one on a 120.
My buddy bought lunch today at the ham radio swap so had had money left to burn. I burned a few more pennies worth of Liquid Gold and have some numbers to report.
My old, well worn, early model POS FA-62 was clamped into the iron and flogged with some rather hefty plastic sticks. For direct , relative comparison to the oft overlooked and belittled FA-65, I ran the same propeller trio on the FA-62 that I earlier ran on the FA-65. Fuel from the exact same batch, weather, near identical as well. These props are fairly tough loads for the baby FA-62 but they are the same props I used for the stout cased FA-65.
All props are APC
12.5-6 FA-62 9550 RPM, FA-65 10,850 RPM
13-6 FA-62 9200 RPM, FA-65 10,300 RPM
13-8 FA-62 8350 RPM, FA-65 9700 RPM
This FA-62 is fitted with the extra long, machined from solid bar, velocity stack I have shown here before. I rarely mention on line that that stack does have a positive RPM gain over no stack or even the factory supplied stack. It is precisely sized and aligned to the carb inlet and the bell is an exponential horn rather than a simple, straight horn. It works, but to say so online guffaws and scorn are sure to ensue, so be it. Any body is welcome to visit and see for themselves. I did take advantage of the fresh runs with that stack and decided to pull it off for comparison. I took great care to get an absolute max reading.without the stack. While short stacks typically show little, if any gain, a longer, bell shaped stack, match sized and ALIGNED for smooth, bump-free transition at the joining, can indeed work.
APC 12.5-6 With stack, 9550 RPM, Without stack, 9400 RPM
These props are not the props I typically ran on the FA-62 as it does prefer lighter loads and higher RPM to get into it's realm. Stroke to bore relationships come into play.
Also consider, both engines are running the same carburetor part number IIRC.
Machined, wide, true exponential long stack matched diameter intake.
Last edited by Jesse Open; 11-08-2020 at 06:37 PM.
11-08-2020, 05:44 PM
Interested to know how those $4 GP work out. I need to restock I think I have 2 merlins left. I started polishing the wing for the Corsair. Looking pretty good, especially my blend considering it was the first one, and used lacquer thinner instead of the proper reducer to edge it in. It will never look like a car finish since it is on wood, but will look good enough flying. I used 4 grades wet dry to get it smooth, then Meguiars compound and a DA to bring up the gloss. Once I have it all to my liking I can go over it with some of my high end final polish to make it really shine. Looking at it, you would never know it was house paint.
11-08-2020, 06:05 PM
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Jim, I didnt forget about your concerns with the weight penalty when replacing an FA100 with an FG21 in a 60 size warbird. Just did it.
I had to add 3-1/2 oz. of weight to the tail to balance out the FG21, larger prop, ignition box, 6.6v LiFe Batt and IBEC. Total added weight was 15-1/2 oz. Sounds like a lot but the flying weight is only 8 oz. heavier due to carrying around half the fuel weight. I also swapped out the mechanical metal/plastic retracts that used a single JR servo to Eflite electric retracts, that could account for a little of the added total weight.
Keep in mind that this is on a nose heavy TF P51 ARF which had already had 1.75 oz. of lead in the tail to balance an FA100. On a plane requiring a lot of nose weight for balance the weight penaly could be much less, if any.
Have to see how it flies but one thing for sure is I'll be able to fly all day on pennies.
I had to add 3-1/2 oz. of weight to the tail to balance out the FG21, larger prop, ignition box, 6.6v LiFe Batt and IBEC. Total added weight was 15-1/2 oz. Sounds like a lot but the flying weight is only 8 oz. heavier due to carrying around half the fuel weight. I also swapped out the mechanical metal/plastic retracts that used a single JR servo to Eflite electric retracts, that could account for a little of the added total weight.
Keep in mind that this is on a nose heavy TF P51 ARF which had already had 1.75 oz. of lead in the tail to balance an FA100. On a plane requiring a lot of nose weight for balance the weight penaly could be much less, if any.
Have to see how it flies but one thing for sure is I'll be able to fly all day on pennies.
Jim
11-08-2020, 06:11 PM
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Gary, the front wall is a little thicker than the stock muffler cap so I cut a groove on the front face that was angled so that when the drill bit approached the cap it had a surface perpendicular to the drill center to start. The exit holes are really close to evenly spaced, hard to do without a verticle mill. I had some fun and learned as I went along.
I'll report back on the FireBall Standards.
I'll report back on the FireBall Standards.
11-08-2020, 06:21 PM
Gary I made a muffler cap for the 220 muffler you sent me, it seemed like a project I could handle and I got one made. Hidden inside are six 4mm exit holes on a much shallower angle than the stock muffler cap. Not intentional, it just turned out that way. So who has a 220 to try it out? If it becomes one of those very large pictures I may be embarrassed.
11-09-2020, 05:54 AM
Excellent, nice how that all came together.
Dave, do you have a FA-62? I would like to send you the same three props that I ran on my old beater FA-62. Be interesting to se your numbers.
Dave, do you have a FA-62? I would like to send you the same three props that I ran on my old beater FA-62. Be interesting to se your numbers.
11-09-2020, 07:18 AM
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Yes I do, I would be glad to compare a few props. Do you have an idea of the approximate dimensions for a tuned velocity stack for a 180. I have one in the rough on the lathe. Thanks
11-09-2020, 08:11 AM
So I was looking at the 120R3 and wondering how to make an exhaust system that routes out the correct location on the Corsair. If I model the F4U-1D, that would require modifying the fuse, don't want to do that. The alternative is the -4 variant where the exhaust comes out just above the wing, but the -4 also had a 4 bladed prop. Either case, what I need it 7mm tubing that I can bend, and 10 mm hex stock to machine the nuts. What material should I use for both? I found 7mm x 300mm copper, but looks like it is not the bendable grade. It will need to be bent beyond 90* for at least one pipe, not an elbow bend but a radius bend of about an inch or so.
Also what thread are the nuts, will need a die for those. My lathe doesn't have the thread cutting attachment, https://www.sherline.com/product/310...ng-attachment/ yet.
Also what thread are the nuts, will need a die for those. My lathe doesn't have the thread cutting attachment, https://www.sherline.com/product/310...ng-attachment/ yet.
11-09-2020, 09:07 AM
Metric hex material, free machining C1045 is a good choice. Cuts cleaner than cold rolled steel resulting in smoother threads when done correctly. With aluminum mating threads hardness is not an issue. I do have some and can send it.
KS Tubing, the stuff in hobby shops, now handles 7mm brass tubing, you may need to special order. They have it on the shelf at our LHS; Prop Shop Hobbies in Warren MI and they do have a website. Hard drawn copper can and should be annealed before and during the forming operations as it work hardens with every move. Try to find some bearing balls that will pass thru the tube, the closer to size, the better as long as they pass thru. Get enough to more than fill the tube. They come in handy for removing kinks as you go or when done. Just drop them in one after another and tap thru as needed. Sometimes helps to have a smaller set too, just to get started.
The quality of the thread cutting does can matter. eBay can be a toss up , I buy everything Metric from Metrics Unlimited in Warren, MI, Drills, taps, dies, metric hex bar etc. They also have a website but they do have a lot more on hand than just what is seen on the site. Got to call. The guy may seem a bit abrupt and grumpy but he really is a good fellow.
If you find him difficult, let me know, they are close by and I can pick up what you need and send it out. Likewise the 7mm brass from Prop Shop. I need to pick up some props anyhow so I can get you some tube. Prop Shop and Metrics Unlimited are both very nearby. I am also headed that way to get some methanol for next years fuel .
KS Tubing, the stuff in hobby shops, now handles 7mm brass tubing, you may need to special order. They have it on the shelf at our LHS; Prop Shop Hobbies in Warren MI and they do have a website. Hard drawn copper can and should be annealed before and during the forming operations as it work hardens with every move. Try to find some bearing balls that will pass thru the tube, the closer to size, the better as long as they pass thru. Get enough to more than fill the tube. They come in handy for removing kinks as you go or when done. Just drop them in one after another and tap thru as needed. Sometimes helps to have a smaller set too, just to get started.
The quality of the thread cutting does can matter. eBay can be a toss up , I buy everything Metric from Metrics Unlimited in Warren, MI, Drills, taps, dies, metric hex bar etc. They also have a website but they do have a lot more on hand than just what is seen on the site. Got to call. The guy may seem a bit abrupt and grumpy but he really is a good fellow.
If you find him difficult, let me know, they are close by and I can pick up what you need and send it out. Likewise the 7mm brass from Prop Shop. I need to pick up some props anyhow so I can get you some tube. Prop Shop and Metrics Unlimited are both very nearby. I am also headed that way to get some methanol for next years fuel .
11-09-2020, 02:09 PM
I built one of the original World Engines version Robin Hood kits around 1981. Real fun plane and looks quite nice in the air. Used a Super Tigre X-25 engine and as I recall a bit over powered at that.
May have to pick up one log the new versions. Let us know how the kit looks.
May have to pick up one log the new versions. Let us know how the kit looks.
11-09-2020, 02:09 PM
I found some small stock items to play with including copper 7MM tubing on Amazon that I can play with, can't find 10mm hex, only 3/8 stainless or brass, and I know stainless and aluminum don't play well. I found 10mm hex bar from Mcmaster Carr, but don't know shipping costs until the order is placed. A different site I found a few items I could use, but the shipping costs just as much as the materials. A $44 came out to $84 by the time I was done. I will check the local place in Rockford and see what they have in the way of Hex stock. I have to get the P-61 plans out and see how much of the landing gear is drawn up to get an idea of the material I need to make retractable gears for it. I put the steel tubing and solid rod that would be needed for the B-25 struts, 24" long each would be enough to machine the mains and nose on the lathe, and when I got the shipping costs, for just a few pounds, I was, NOPE. So will check with the Rockford place, and call in for a pickup if they have it. $16 to ship a $2 piece of steel! Need a 9 x .75 die too, searching for that now.
I like the idea of using steel bals for the tubing, so will need to find out the inside diameter of the tubing, I think it is .02mm walls, so that would make it 6.6mm inside diameter, but have to verify. Could probably get away with using .250 bearings for this.
I like the idea of using steel bals for the tubing, so will need to find out the inside diameter of the tubing, I think it is .02mm walls, so that would make it 6.6mm inside diameter, but have to verify. Could probably get away with using .250 bearings for this.
11-09-2020, 03:04 PM
11-09-2020, 04:04 PM
11-09-2020, 05:01 PM
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That's beautiful Andy, thanks for the picture.
Gary, here is the big one, second down: https://www.radicalrc.com/category/Kits-145
Gary, here is the big one, second down: https://www.radicalrc.com/category/Kits-145
11-09-2020, 05:57 PM
The little one with three channels is my choice.
A nice four stroke glow engine, simple and sweet.
A nice four stroke glow engine, simple and sweet.
Last edited by Jesse Open; 11-09-2020 at 06:07 PM.