Charlie Kellogg's TBM Avenger Build
10-05-2009, 08:40 PM
#401
RE: Charlie Kellogg's TBM Avenger Build
Hello Everyone,
I hope you do not mind me slipping in to invite you to Oklahoma and WARBIRDS OVER OKLAHOMA May 14 - 16, 2010.
Sure would be nice to see some of this fine work sporting the skies above the airport in El Reno, OK. Please see and share the information on the attached flier.
WARBIRDRCER
I hope you do not mind me slipping in to invite you to Oklahoma and WARBIRDS OVER OKLAHOMA May 14 - 16, 2010.
Sure would be nice to see some of this fine work sporting the skies above the airport in El Reno, OK. Please see and share the information on the attached flier.
WARBIRDRCER
10-19-2009, 10:11 AM
#403
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RE: Charlie Kellogg's TBM Avenger Build
Although I have only spent a sum total of 3 hrs on the plane in the past two weeks (thus, not much new to share, sorry), I noticed that this thread was getting pushed almost all the way to page 4 of the forum… that’s too little activity!
So, I thought I would “update†the thread with some older photos detailing the flap construction, cowl attachment and control surface preparation.
We’ll start with the flaps: Now most of you (I’m sure) end up with wing trailing edges that are perfectly true, but on this build I did not fall into that category. My trailing edge had a slight bit of waviness to it when it was all said and done. Note, I’m not talking about the flap hinge-line (which is perfectly straight), I’m talking about the actual trailing edge of the upper wing surface balsa sheeting. So, if I built the flaps on a perfectly flat work-surface, the trailing edge of the flap would not evenly meet the trailing edge of the wing. Thus, the flaps were built in place on the wing. This ensures that the surfaces meet up perfectly, despite any imperfection of the wing trailing edge.
The upper surface of the flap is 1/32 ply. The leading edge is ¼ square balsa. The location of each hinge along the flap leading edge was first verified by reassembling the hinges. For additional support, where the hinges attach, light ply was glued to the flap upper surface ply. I also added a ply support for the control horn. Once marked, the flap leading edge and hinge support ply was notched to accommodate the depth of the hinges. The support blocks were also planed down at an angle that sloped to the trailing edge. The flap side hinge-halves were screwed in place. I used screws that protruded all the way through the other side. The excess length was ground off the screws later.
The trailing edge was attached next. This was a piece of ¼ square spruce. Here is where you make the surfaces mate perfectly. With the flap hinged and in place on the wing, the spruce trailing edge and the 1/32 ply flap upper surface were gently clamped to the upper surface of the wing trailing edge. Once all was aligned, the spruce was glued to the 1/32 ply (thin CA wicked). After it was set, the cotter pins were removed and the spruce trailing edge of the flap was razor-planed at an angle to match the leading-to-trailing edge contour. After that, additional ¼ square balsa support stock was glued from leading to trailing edge. The flap was finished by sanding the ¼ square balsa to match the flap contour and finally sheeting with 1/16 balsa. Bottom balsa surfaces were glassed. This was simply repeated for the other side. The inner flap surfaces were much easier to make since those were perfectly rectangular.
So, I thought I would “update†the thread with some older photos detailing the flap construction, cowl attachment and control surface preparation.
We’ll start with the flaps: Now most of you (I’m sure) end up with wing trailing edges that are perfectly true, but on this build I did not fall into that category. My trailing edge had a slight bit of waviness to it when it was all said and done. Note, I’m not talking about the flap hinge-line (which is perfectly straight), I’m talking about the actual trailing edge of the upper wing surface balsa sheeting. So, if I built the flaps on a perfectly flat work-surface, the trailing edge of the flap would not evenly meet the trailing edge of the wing. Thus, the flaps were built in place on the wing. This ensures that the surfaces meet up perfectly, despite any imperfection of the wing trailing edge.
The upper surface of the flap is 1/32 ply. The leading edge is ¼ square balsa. The location of each hinge along the flap leading edge was first verified by reassembling the hinges. For additional support, where the hinges attach, light ply was glued to the flap upper surface ply. I also added a ply support for the control horn. Once marked, the flap leading edge and hinge support ply was notched to accommodate the depth of the hinges. The support blocks were also planed down at an angle that sloped to the trailing edge. The flap side hinge-halves were screwed in place. I used screws that protruded all the way through the other side. The excess length was ground off the screws later.
The trailing edge was attached next. This was a piece of ¼ square spruce. Here is where you make the surfaces mate perfectly. With the flap hinged and in place on the wing, the spruce trailing edge and the 1/32 ply flap upper surface were gently clamped to the upper surface of the wing trailing edge. Once all was aligned, the spruce was glued to the 1/32 ply (thin CA wicked). After it was set, the cotter pins were removed and the spruce trailing edge of the flap was razor-planed at an angle to match the leading-to-trailing edge contour. After that, additional ¼ square balsa support stock was glued from leading to trailing edge. The flap was finished by sanding the ¼ square balsa to match the flap contour and finally sheeting with 1/16 balsa. Bottom balsa surfaces were glassed. This was simply repeated for the other side. The inner flap surfaces were much easier to make since those were perfectly rectangular.
10-19-2009, 10:13 AM
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RE: Charlie Kellogg's TBM Avenger Build
I thought I would also share some shots of the trim tab details on the control surfaces. The tabs were built-up balsa, which was eventually glassed. The tabs were glued to the control surfaces. To make the “control arms,†I used a snipped-off servo arm embedded and glued into the trim tab. The actuating rod was just 1/16 music wire soldered to a metal clevis. The clevis was cut shorter, and because I cut off the pin on the clevis, I simply just glued the clevis to the control arm. Note: some balsa was glued into the control surface before I covered them so the music wire would have something to stick into. CA wicked down the length of the wire held it securely within the control surface. Finally, some plastic tubing was cut at an angle and attached where the rod exits the control surface.
The trim tabs actuating mechanisms are present on the upper surfaces of both ailerons, the right side of the rudder, the upper side of the left elevator half, and the lower side of the right elevator half. I think they turned out pretty good. They are a bit too large for scale, but because they are a bit larger, they are easy to see and appreciate when viewed from a few ~10 feet away. The photos are not the best, sorry.
The trim tabs actuating mechanisms are present on the upper surfaces of both ailerons, the right side of the rudder, the upper side of the left elevator half, and the lower side of the right elevator half. I think they turned out pretty good. They are a bit too large for scale, but because they are a bit larger, they are easy to see and appreciate when viewed from a few ~10 feet away. The photos are not the best, sorry.
10-19-2009, 10:32 AM
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RE: Charlie Kellogg's TBM Avenger Build
I’m not certain that my cowl mounting will hold-up in the long run. I may have to re-think this for two reasons: 1) it’s going to be difficult to get the mounting bolts in place once the motor is mounted and the baffling is attached to the cowl; 2) the cowl has a pretty good chance of simply falling off the front of the plane based on how I mounted it!
My approach: To avoid unsightly mounting bolts on the exterior of the cowl, I chose to glue some ply tabs (like a semi-ring) to the inner surface of the cowl. 10-24 bolts pass through the tabs and are secured to the balsa ring. There are threaded inserts glued into the balsa ring so that the 10-24 bolts have something to bite into. This is where it may be dicey… I’m worried that the inserts are going to eventually pull out with some stresses on the balsa. I did soak the balsa pretty well with CA, but I’m starting to sense that this system might fail in the long run. I suppose I just need to test them by applying pressure and tension. We’ll see. I may have to go another route.
Suggestions?
My approach: To avoid unsightly mounting bolts on the exterior of the cowl, I chose to glue some ply tabs (like a semi-ring) to the inner surface of the cowl. 10-24 bolts pass through the tabs and are secured to the balsa ring. There are threaded inserts glued into the balsa ring so that the 10-24 bolts have something to bite into. This is where it may be dicey… I’m worried that the inserts are going to eventually pull out with some stresses on the balsa. I did soak the balsa pretty well with CA, but I’m starting to sense that this system might fail in the long run. I suppose I just need to test them by applying pressure and tension. We’ll see. I may have to go another route.
Suggestions?
10-19-2009, 10:34 AM
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RE: Charlie Kellogg's TBM Avenger Build
Anyway, once the cowl was mounted, Holes for the fake exhaust stubs and the real exhaust stubs were opened in the cowl and balsa ring, respectively. At this point, I am not willing to attach a funky home-made exhaust system to the radial in an effort to make the scale exhaust stubs functional. If the motor runs well and the planes flies nicely, I may go back and re-do this in the future. The down-side of my decision is that the fake and the real exhaust stubs are kind of close together, especially on the right side of the fuse. Purists may roll their eyes at my decision, but better safe than sorry until the components are proven and the plane flies well.
For the fake exhaust stubs, I picked up some P trap material at the hardware store (thanks, Charlie). I have not yet cut it, but I have them marked. Will likely finish this off this week.
It’s starting to warm up here again (with some sun, too) so I’ll try to get back to filling/sanding/priming the fuse and wings so that they will be truly ready for panel lines and rivets.
Will post again soon.
Noah
For the fake exhaust stubs, I picked up some P trap material at the hardware store (thanks, Charlie). I have not yet cut it, but I have them marked. Will likely finish this off this week.
It’s starting to warm up here again (with some sun, too) so I’ll try to get back to filling/sanding/priming the fuse and wings so that they will be truly ready for panel lines and rivets.
Will post again soon.
Noah
10-19-2009, 11:11 AM
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RE: Charlie Kellogg's TBM Avenger Build
One thing that I forgot to explain regarding the mating of the trailing edge of the flaps and wing...
Clamping the 1/4 spruce trailing edge and the 1/32 ply along wing trailing edge makes the spruce and the ply "slide" past one another as they conform to the bend in the wing edge. Once glued, the surfaces (generally) do not return to their original shape (flat). So, this is the real rationale for doing it this way. It's very effective, and even though most of the spruce trailing edge material is eventually razor-planed away, the flap still maintains it's contour to match the wing. The 1/4 balsa stringers and the 1/16 surface sheeting also combine to help maintain the shape when the flap is built in place.
OK, that's it. Will post again soon.
Noah
Clamping the 1/4 spruce trailing edge and the 1/32 ply along wing trailing edge makes the spruce and the ply "slide" past one another as they conform to the bend in the wing edge. Once glued, the surfaces (generally) do not return to their original shape (flat). So, this is the real rationale for doing it this way. It's very effective, and even though most of the spruce trailing edge material is eventually razor-planed away, the flap still maintains it's contour to match the wing. The 1/4 balsa stringers and the 1/16 surface sheeting also combine to help maintain the shape when the flap is built in place.
OK, that's it. Will post again soon.
Noah
10-19-2009, 06:27 PM
#408
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RE: Charlie Kellogg's TBM Avenger Build
Ok, now it's getting bad. About the time I start thinking I need my Avenger fix....over flies the full scale again yesterday....this time I was ready, and had the binoculars out for a better view. 
...and then, followed up with the awesome shots of the bird here in primer Noah....and of course to top it all off, of course there's the crucial "missing ingredient"....the bottle of Fat Tire on the workbench....my favorite beverage aside from coffee. Ugh. I might as well just bite the proverbial bullet and buy one of these things as it's just rubbing it in now 
For real...it looks awesome Noah. Great job again.
M.
...and then, followed up with the awesome shots of the bird here in primer Noah....and of course to top it all off, of course there's the crucial "missing ingredient"....the bottle of Fat Tire on the workbench....my favorite beverage aside from coffee. Ugh. I might as well just bite the proverbial bullet and buy one of these things as it's just rubbing it in now For real...it looks awesome Noah. Great job again.M.
10-21-2009, 07:53 AM
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RE: Charlie Kellogg's TBM Avenger Build
My approach: To avoid unsightly mounting bolts on the exterior of the cowl, I chose to glue some ply tabs (like a semi-ring) to the inner surface of the cowl. 10-24 bolts pass through the tabs and are secured to the balsa ring. There are threaded inserts glued into the balsa ring so that the 10-24 bolts have something to bite into. This is where it may be dicey… I’m worried that the inserts are going to eventually pull out with some stresses on the balsa. I did soak the balsa pretty well with CA, but I’m starting to sense that this system might fail in the long run. I suppose I just need to test them by applying pressure and tension. We’ll see. I may have to go another route.
Suggestions?
Suggestions?
Your approach is correct; however, IMHO, I feel your method will not withstand the vibration/oscillation of a gas engine used on your model.
If all possible, fabricate a 360 degree cowl ring from 1/4" ply and glass this into the cowling at the depth required by the firewall standoffs. In other words, construct, say four or five 1" x 2" hardwood blocks of the proper depth, pin and glue (epoxy only) to the perimeter of firewall. Plan their staggered location properly, so they don't interfere with engine components and you can view them from the front. Once you have the cowl ring made to fit snug within the fiberglass cowling, position the cowling onto the model and push the ring up against the glued firewall blocks. Tack glue the cowl ring (w/ CA) to the cowling sides, slide the cowling back and remove. Now fiberglass the ring inside the cowling, using strips of 3-6 oz. fiberglass cloth and structural epoxy. Once everything's cured, you can refit the cowling, match up to the firewall blocks and drill small pilot holes (w/ 12" long bits) throught the cowl ring and into the firewall blocks. Drill to size and tap. I would highly suggest using only 1/4 x 20 nylon bolts w/ nylon washers. Yes, nylon. They do not back out and hold up perfectly fine. Also, order yourself those allen head cap types. Forget using a flat blade screwdriver slot style. Now go purchase a set of those El Cheapo Chinese hex drivers (Harbor Freight), cut the selected size and extend the tool 18". I use 1/8" music wire and braze. This allows you to reach inside the cowling through the front of the model, effectively removing the cowl assembly.
Lastly, you may need to trim away sections the the cowl ring to allow clearance for mufflers, ignition modules, etc. Only do this if absolutely necessary, as this will reduce the integrity of the ring mounting.
I've used this system for 15 years on giant gas-powered heavy-metal warbirds and never had a cowling mount become loose and/or fail. Plus the appearance speaks for itself.
Good Luck, NICK
10-22-2009, 07:51 AM
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RE: Charlie Kellogg's TBM Avenger Build
Thanks for the comments, Nick.
Turns out that the threaded inserts were not difficult to pull out of the balsa... As Nick suggested, and as I suspected, it would have never lasted with vibration and oscillation. My new method will involve the installation of 5-6 locator pins (3/8 hardwood dowels) passing though the balsa ring into the 1/4 ply firewall and units of Tesla...
Just waiting for the magnets to arrive.
If the magnetic installation also looks suspect, I have a "plan C," too.
I will reveal my plan B results this weekend.
Mike, anytime you're traveling west along I-80, get in touch. I'll have a cold Fat Tire waiting for you!
Regards,
Noah
Turns out that the threaded inserts were not difficult to pull out of the balsa... As Nick suggested, and as I suspected, it would have never lasted with vibration and oscillation. My new method will involve the installation of 5-6 locator pins (3/8 hardwood dowels) passing though the balsa ring into the 1/4 ply firewall and units of Tesla...
Just waiting for the magnets to arrive.
If the magnetic installation also looks suspect, I have a "plan C," too.
I will reveal my plan B results this weekend.
Mike, anytime you're traveling west along I-80, get in touch. I'll have a cold Fat Tire waiting for you!
Regards,
Noah
10-22-2009, 08:00 PM
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RE: Charlie Kellogg's TBM Avenger Build
Rotfl Noah. No worries, I'll supply them. My parents live about a half hour from Davenport, so perhaps at some point, we'll see.
Nick's got it right on the cowl too...that's the way I attached my 190D cowl that you saw at Fon du Lac. Aside from finding the bolts inside the cowl with the driver, it works awesome. Keep on trucking. Looks fantastic.
My parents live about a half hour from Davenport, so perhaps at some point, we'll see.Nick's got it right on the cowl too...that's the way I attached my 190D cowl that you saw at Fon du Lac. Aside from finding the bolts inside the cowl with the driver, it works awesome. Keep on trucking. Looks fantastic.
10-23-2009, 05:12 PM
#412
RE: Charlie Kellogg's TBM Avenger Build
Noah,
Sorry for the delay in posting, as always your work is TOTALLY Awesome, our update is finally got the 2nd light coat of resin on the fuse and will get it sanded and primed next week. Started working on the hinges on the bomb bay doors... tougher than we thought, but het who said this would be easy.
Loved the trim tabs you made, they look awesome, something else we will need to add to ours
.. hopefully I can get some pix posted of the fuse with wings attached by next week... I'm working on the frames for the windows, which I am painstakingly cutting for .20 styrene, I have the 2 large frames made and hopefully the 2 smaller ones this weekend. Oh that's right after fixing a wingtip for a friend of mine.. weather calls for strong winds and rain and Saturday but bright skies on Sunday.. oh yeah and wind gusts over 20mph another lost weekend of flying...
Take care and once again my kudos to you for the build and to your wife for putting up with it..LOL
Larry
Sorry for the delay in posting, as always your work is TOTALLY Awesome, our update is finally got the 2nd light coat of resin on the fuse and will get it sanded and primed next week. Started working on the hinges on the bomb bay doors... tougher than we thought, but het who said this would be easy.
Loved the trim tabs you made, they look awesome, something else we will need to add to ours
.. hopefully I can get some pix posted of the fuse with wings attached by next week... I'm working on the frames for the windows, which I am painstakingly cutting for .20 styrene, I have the 2 large frames made and hopefully the 2 smaller ones this weekend. Oh that's right after fixing a wingtip for a friend of mine.. weather calls for strong winds and rain and Saturday but bright skies on Sunday.. oh yeah and wind gusts over 20mph another lost weekend of flying...Take care and once again my kudos to you for the build and to your wife for putting up with it..LOL
Larry
10-25-2009, 07:55 PM
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RE: Charlie Kellogg's TBM Avenger Build
Hi, Larry.
Glad to hear that you're still chipping away at the plane. I know the bomb bay doors can be a little tedious, but they'll be well worth it in the end. I hope that others who have checked out this thread, and are considering building the Avenger from Charlie Kellogg, don't get frightened away by the apparent complexity of the kit... it's not that complex, and it's really a straightforward build. It's all the scale details that take time and effort!
Shoot me some pictures when you get around to it, Larry. I'm looking forward to seeing your progress.
So, I spent a few hours on my Avenger this weekend. The major task that I knocked out was the installation of the cowl and the baffling of the engine. As I indicated earlier, I decided to not use standard fasteners but instead magnets. I installed 5 locator/alignment pins (5/16 hardwood dowels that pass all the way through the balsa cowl ring and into the firewall) and 4 magnets, each with 8 lbs of holding force. The cowl is snugly attached to the fuse, and I have no doubt that it will remain in place and not fall away from the firewall when the engine is running or while the plane is in flight. It's actually pretty tough to pull it off the plane (I needed the help of my wife, to be honest). Nevertheless, I'll do some extensive testing before actually taking flight with this set-up.
Anyway, I forgot to shoot some pictures of the magnets and pins, but did get some of the baffling. To make the baffling, I first cut a cardboard disk that fit into the cowl at the appropriate depth, then I traced this onto some 3/32 ply. Next I made a cardboard template for the actual baffling. The baffling pattern was then also traced onto the 3/32 aircraft ply. I cut the perimeter of the ply and installed the disk into the cowl with methacrylate before I started cutting out the baffling voids. Once the adhesive was cured, I slowly opened spaced between the baffles, continually checking and re-checking the fit on the plane with the engine installed. In the end it came out pretty good, but it took a fairly long time. The baffles will be glassed tonight... More for accepting paint (i.e. resisting oil!) rather than strength... they are plenty strong and well-secured inside the cowl. Hopefully they'll do the job and force the air over the cylinders and out the cowl flaps. I might also open the cowl flaps a little wider, just to be sure there's plenty of negative pressure back there to suck out the hot air around the cylinders.
Glad to hear that you're still chipping away at the plane. I know the bomb bay doors can be a little tedious, but they'll be well worth it in the end. I hope that others who have checked out this thread, and are considering building the Avenger from Charlie Kellogg, don't get frightened away by the apparent complexity of the kit... it's not that complex, and it's really a straightforward build. It's all the scale details that take time and effort!
Shoot me some pictures when you get around to it, Larry. I'm looking forward to seeing your progress.
So, I spent a few hours on my Avenger this weekend. The major task that I knocked out was the installation of the cowl and the baffling of the engine. As I indicated earlier, I decided to not use standard fasteners but instead magnets. I installed 5 locator/alignment pins (5/16 hardwood dowels that pass all the way through the balsa cowl ring and into the firewall) and 4 magnets, each with 8 lbs of holding force. The cowl is snugly attached to the fuse, and I have no doubt that it will remain in place and not fall away from the firewall when the engine is running or while the plane is in flight. It's actually pretty tough to pull it off the plane (I needed the help of my wife, to be honest). Nevertheless, I'll do some extensive testing before actually taking flight with this set-up.
Anyway, I forgot to shoot some pictures of the magnets and pins, but did get some of the baffling. To make the baffling, I first cut a cardboard disk that fit into the cowl at the appropriate depth, then I traced this onto some 3/32 ply. Next I made a cardboard template for the actual baffling. The baffling pattern was then also traced onto the 3/32 aircraft ply. I cut the perimeter of the ply and installed the disk into the cowl with methacrylate before I started cutting out the baffling voids. Once the adhesive was cured, I slowly opened spaced between the baffles, continually checking and re-checking the fit on the plane with the engine installed. In the end it came out pretty good, but it took a fairly long time. The baffles will be glassed tonight... More for accepting paint (i.e. resisting oil!) rather than strength... they are plenty strong and well-secured inside the cowl. Hopefully they'll do the job and force the air over the cylinders and out the cowl flaps. I might also open the cowl flaps a little wider, just to be sure there's plenty of negative pressure back there to suck out the hot air around the cylinders.
10-25-2009, 07:59 PM
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RE: Charlie Kellogg's TBM Avenger Build
One of the other things that I got a start on today was the turrret inner-workings.
I made all of the parts from styrene and balsa, and a small length of air line tubing that was glued behind the gunner's seat for effect. Basically I was patterning my gun turret after Charlie Kellogg's photos. I still have a bunch of detail to add, including the 50 cal. gun, but that will have to wait until later this week. The bullet-proof shielding (taped over in the photos) was cut from the clear outer case from a music CD. Good material, nice and stiff and crystal clear. No fogging when using CA, either.
I made all of the parts from styrene and balsa, and a small length of air line tubing that was glued behind the gunner's seat for effect. Basically I was patterning my gun turret after Charlie Kellogg's photos. I still have a bunch of detail to add, including the 50 cal. gun, but that will have to wait until later this week. The bullet-proof shielding (taped over in the photos) was cut from the clear outer case from a music CD. Good material, nice and stiff and crystal clear. No fogging when using CA, either.
10-25-2009, 08:04 PM
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RE: Charlie Kellogg's TBM Avenger Build
Speaking of the 50 cal. gun, Chic (redtail), my friend that started this thread, sent me a gift many months ago: a perfectly scaled 50 cal gun for the Avenger.
Unfortunately, this gun might be way too heavy (it's straight die-cast metal). I'm not overly concerned about adding weight aft of the recommended CG, but more worried that my light-weight turret will not hold up. The styrene will collapse under the weight of the gun. I will continue to think about this installation. I wish the gun were lighter, though! We'll see.
Unfortunately, this gun might be way too heavy (it's straight die-cast metal). I'm not overly concerned about adding weight aft of the recommended CG, but more worried that my light-weight turret will not hold up. The styrene will collapse under the weight of the gun. I will continue to think about this installation. I wish the gun were lighter, though! We'll see.
10-25-2009, 08:13 PM
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RE: Charlie Kellogg's TBM Avenger Build
So this is basically where I am as of today. Some more sanding and filling on the fuse and wings, and then it'll be onto panel lines and rivets. I know I say that every week... but seriously, one of these days I'll get to it.
By the way, I think that I'm going to come in at right about 50 lbs. This thing is getting heavy, baby!!! At least Brian reports that this model will fly well at this higher weight. Once I get it all assembled, with some of the radio gear installed, I get a weight on the model.
Maybe I'll share the numbers here (maybe not!).
Regards,
Noah
By the way, I think that I'm going to come in at right about 50 lbs. This thing is getting heavy, baby!!! At least Brian reports that this model will fly well at this higher weight. Once I get it all assembled, with some of the radio gear installed, I get a weight on the model.
Maybe I'll share the numbers here (maybe not!).
Regards,
Noah
10-25-2009, 08:45 PM
#417
RE: Charlie Kellogg's TBM Avenger Build
You are my hero Noah, so glad to see you pressing on. You work is outstanding and very educational for those of us still building and well behind your accomplishments. Of course we will use your instruction and advice. You will make all of our builds go soooo much smoother. Great news, I have just been released to start lifting stuff and I spent the day in the shop cleaning, moving stuff around. Had a few aches and pains but I expected a few of those. I stood looking at the "DAWG" which I will work on first as you suggested. The "Avenger" looks safe and sound in its spot and is waiting its turn. I'm sure you are right about the weight of the 50 cal., did not think about that, you are right about it being something to consider (weight wise) even though they do look good. Keep up the great build and I for sure will keep watching. Chic (Redtail)
10-26-2009, 05:49 AM
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RE: Charlie Kellogg's TBM Avenger Build
Hi, Chic.
Good to hear from you, and I'm glad that your shoulder has been cleared for additional activity. Do what you can when you can. Looking forward to seeing updates on the Dawg in time on the other thread.
I'm still trying to come up with a way to make the gun work... but it's literally about 4.5 oz, and this will be way too much stress for my little plastic gun turret. I think that I can get it in securely, but it's going to take some strategically placed reinforcments.
I'll continue to work on the gun installation this week as I add the additional details to the turret.
Chic have you heard from Frank lately? I wonder if he's flying his Avenger already?!?
Speak with you soon.
Noah
Good to hear from you, and I'm glad that your shoulder has been cleared for additional activity. Do what you can when you can. Looking forward to seeing updates on the Dawg in time on the other thread.
I'm still trying to come up with a way to make the gun work... but it's literally about 4.5 oz, and this will be way too much stress for my little plastic gun turret. I think that I can get it in securely, but it's going to take some strategically placed reinforcments.
I'll continue to work on the gun installation this week as I add the additional details to the turret.
Chic have you heard from Frank lately? I wonder if he's flying his Avenger already?!?
Speak with you soon.
Noah
10-26-2009, 04:55 PM
#419
RE: Charlie Kellogg's TBM Avenger Build
Noah,
Here's a thought for the gun, this months Model Airplane News has an article who won this years Top Gun with a highly detailed F-16 cockpit. He goes through the steps and said in the article that he made a lot of silicone molds to make resin castings. This might be the ticket for the 50 cal., would probably save a ton of weight and the detail should hold pretty well. Should it work we would be willing to pay you for a pair
.
Let me know what you think. BTW, we start final sanding before primer on the fuse Wed, I started on the bomb bay doors today, we are slightly counter sinking the screw holes for the mounting screws on the hinges.
I am following your advise about only putting in 4 screws until everything is lined up... I will have some pix for you next week after we get a coat of primer on the fuse.
Keep up the excellent work, it gives us something to strive for.
Larry
Here's a thought for the gun, this months Model Airplane News has an article who won this years Top Gun with a highly detailed F-16 cockpit. He goes through the steps and said in the article that he made a lot of silicone molds to make resin castings. This might be the ticket for the 50 cal., would probably save a ton of weight and the detail should hold pretty well. Should it work we would be willing to pay you for a pair
.Let me know what you think. BTW, we start final sanding before primer on the fuse Wed, I started on the bomb bay doors today, we are slightly counter sinking the screw holes for the mounting screws on the hinges.
I am following your advise about only putting in 4 screws until everything is lined up... I will have some pix for you next week after we get a coat of primer on the fuse.
Keep up the excellent work, it gives us something to strive for.
Larry
10-26-2009, 04:59 PM
#420
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RE: Charlie Kellogg's TBM Avenger Build
Hey, Larry.
I'll look at the article. Thanks for the heads-up. If it's not too bad, I would gladly make a set for you.
Looking forward to seeing your Avenger!
Noah
I'll look at the article. Thanks for the heads-up. If it's not too bad, I would gladly make a set for you.
Looking forward to seeing your Avenger!
Noah
10-26-2009, 06:10 PM
#421
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RE: Charlie Kellogg's TBM Avenger Build
Noah, I'm pretty sure I've got a set of .50's here from Dynamic balsa in probably the right scale that you could have if you want a lighter set for flying purposes and the heavier ones for display. Turned out I didn't need them. I know I've got at least one somewhere. Just LMK and I can get measurements and stuff if you need it. They don't look as nice as the metal one obviously, but they're not bad at all.
Checked, and I have one gun, which measure 8.25" long from stock to barrel tip and 6" of ammo belt and bullets. Yours if you need it.
M.
Checked, and I have one gun, which measure 8.25" long from stock to barrel tip and 6" of ammo belt and bullets. Yours if you need it.
M.
10-26-2009, 07:50 PM
#422
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RE: Charlie Kellogg's TBM Avenger Build
Mike, thanks, that's very generous.
I like the sound of swapping the metal out for the Dynamic Balsa gun for flying. I'm going to PM you my email address so we can work something out. Is the DB gun resin?
Too bad about the die-cast being so heavy... it's perfect in every detail. I just don't think that I can get it safely secured for flight.
Will be in touch soon.
Best,
Noah
I like the sound of swapping the metal out for the Dynamic Balsa gun for flying. I'm going to PM you my email address so we can work something out. Is the DB gun resin?
Too bad about the die-cast being so heavy... it's perfect in every detail. I just don't think that I can get it safely secured for flight.
Will be in touch soon.
Best,
Noah
10-26-2009, 09:39 PM
#423
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RE: Charlie Kellogg's TBM Avenger Build
I had a few inquiries as to whether my estimate of 50 lbs was accurate...
I just got up from the shop. I have a pretty accurate set of scales so I weighed everything that I intend to install in the plane (all servos, batteries, receivers, switches, wiring, fuel tank, propeller), as well as all the subassemblies (wing panels, flap sections, cowl, bay doors, control surfaces, etc...) and I came up with 41.3 lbs.
I think that with final paint/stencils, clear coat, canopies and the last of the hardware installed, I'll still be less than 45lbs.
I'm a little surprised, and very relieved (that I will not have to get the plane inspected). I thought for sure I would be pushing 55 when all said and done.
At this weight, I might even be able to stick a pilot and one crew member under the canopy!
That's cause to celebrate with a Fat Tire, Mike! So, off I go.
Noah
I just got up from the shop. I have a pretty accurate set of scales so I weighed everything that I intend to install in the plane (all servos, batteries, receivers, switches, wiring, fuel tank, propeller), as well as all the subassemblies (wing panels, flap sections, cowl, bay doors, control surfaces, etc...) and I came up with 41.3 lbs.
I think that with final paint/stencils, clear coat, canopies and the last of the hardware installed, I'll still be less than 45lbs.
I'm a little surprised, and very relieved (that I will not have to get the plane inspected). I thought for sure I would be pushing 55 when all said and done.
At this weight, I might even be able to stick a pilot and one crew member under the canopy!
That's cause to celebrate with a Fat Tire, Mike! So, off I go.
Noah