Doc James Hammond
Very Strong User
Hey lads! I'm just building up two Redshift f3f planes - would anybody be interested in the process/pics?
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Redshift building: Anybody interested?
- Thread starter Doc James Hammond
- Start date
B
bferg
Guest
Sure, I’m a newbee sponge 
J
JarHeadFlyer71
Guest
awaiting pics! Also need Wayne to let me know when mine arrives.
Doc James Hammond
Very Strong User
Hi Guys - got quite far into it but my pics are too large t pst so what can I do...wail wail...
Help!
Doc.
Help!
Doc.
Doc James Hammond
Very Strong User
Here goes:
Before we start:
Please measure twice and cut once.
The start of fuselage installation should begin with the 20mm x 20 mm ballast tube. As this is a member of considerable strength in its own right, I like to use is to add strength to the fuselage rather than just as a place to add weight.
NOTE that the carbon/glass tube supplied can use USA standard ¾†x ¾â€: (19mm) Brass, Lead in square brass tubes, Refined Osmium, or active Uranium ballast slugs, as well as the metric 20mm x 20mm versions.
So let’s go!
FIRST THING to do is to cut two 20mm x 20mm x 6mm ply end plates. Trim/sand to fit snugly inside the ballast tube.
NEXT, cut the opening for the slugs to be inserted or removed which should be slightly longer than a slug and about half way down the tube, so that you can grab them if needed. Remember to leave the ends intact for the ply end plates:
THEN, decide how long you want you ballast tube. Normally this will be as long as possible, but there are three things to remember:
NOW roughen and degrease the insides of the ballast tube at both ends and epoxy the end plates in. Try not to get too much epoxy inside the tube as this might cause the slugs to bind and there’s nothing worse than a slug stuck inside your tube – as the actress said to the bishop.
MARK THE MIDDLE OF THE SLUG MAGAZINE. That’s the space between the front of the rear ply plate and the BACK of the cut-out section at the front where all the ballast will be stored. In other words, all of the useable contained ballast space. You’ll need to know where this is when bonding-in the ballast tube to make sure the ballast is always around the CG.
OK, when that’s all cured it’s time to add the rails – note that you do not absolutely HAVE to do this but it makes several things easier, and adds a lot of strength to the fuse. I cut two nice straight grain spruce rails, 10mm x 5mm x 630mm (3/8†x 3/16†x 23â€) and then plane them so that one side of the rectangle is reduced to 3mm to account for the curvature of the fuselage. Then I epoxy them to the sides of the ballast tube with about 220mm (8.6â€) sticking out beyond the front of the tube, and the tops about halfway down. The front extensions will provide rails for the radio tray to sit on later.
More next time!
Before we start:
- Working surfaces:
- Your model has a nice high polish, and unfortunately its quite easy to get scratched by sharp tools, abrasive paper, your wife’s fingernails – when she finds out how much you paid for it - or even a slightly gritty surface. So, always use a cradle or at least a soft surface to lay your parts on when working – anything might do – an old blanket, just as long as it won’t scratch your baby, or the plane either.
- Glues not to use:
- There is no place on this airframe for 5-minute epoxy or hot glue. Please don’t use these. Yes, they may save time but I can assure you that you’ll spend a lot more time repairing the plane if they fail, and at worst you won’t be able to.
- Glues to use:
- Slow Epoxy, or failing that, slow epoxy, or as an alternative, slow epoxy.
- Cyanoacrylate – good quality and used in very small gaps, or for “tacking†components in place before securing with Epoxy.
- I have heard good things about Gorilla glue but I have never used it, so I can’t recommend it.
- Preparation:
- Always try to keep the surfaces to be secured clean and especially free of dust or any form of oil – ESPECIALLY - silicon oil or wax.
- Always prepare the surfaces to be bonded by light abrasion, and then by degreasing with good alcohol or acetone etc.
- Always make sure that the components to be secured fit well, with gaps as small as you can manage.
- Ballast tube (see pics below!)
Please measure twice and cut once.
The start of fuselage installation should begin with the 20mm x 20 mm ballast tube. As this is a member of considerable strength in its own right, I like to use is to add strength to the fuselage rather than just as a place to add weight.
NOTE that the carbon/glass tube supplied can use USA standard ¾†x ¾â€: (19mm) Brass, Lead in square brass tubes, Refined Osmium, or active Uranium ballast slugs, as well as the metric 20mm x 20mm versions.
So let’s go!
FIRST THING to do is to cut two 20mm x 20mm x 6mm ply end plates. Trim/sand to fit snugly inside the ballast tube.
NEXT, cut the opening for the slugs to be inserted or removed which should be slightly longer than a slug and about half way down the tube, so that you can grab them if needed. Remember to leave the ends intact for the ply end plates:
THEN, decide how long you want you ballast tube. Normally this will be as long as possible, but there are three things to remember:
- The length of your slugs – I use 35mm (1, 3/8â€)
- The system you will use to keep the slugs in the tube. I use Depron or other hard foam.
- The Centre of gravity, which is 90 to 100mm (3.54†to 3.93â€)
NOW roughen and degrease the insides of the ballast tube at both ends and epoxy the end plates in. Try not to get too much epoxy inside the tube as this might cause the slugs to bind and there’s nothing worse than a slug stuck inside your tube – as the actress said to the bishop.
MARK THE MIDDLE OF THE SLUG MAGAZINE. That’s the space between the front of the rear ply plate and the BACK of the cut-out section at the front where all the ballast will be stored. In other words, all of the useable contained ballast space. You’ll need to know where this is when bonding-in the ballast tube to make sure the ballast is always around the CG.
OK, when that’s all cured it’s time to add the rails – note that you do not absolutely HAVE to do this but it makes several things easier, and adds a lot of strength to the fuse. I cut two nice straight grain spruce rails, 10mm x 5mm x 630mm (3/8†x 3/16†x 23â€) and then plane them so that one side of the rectangle is reduced to 3mm to account for the curvature of the fuselage. Then I epoxy them to the sides of the ballast tube with about 220mm (8.6â€) sticking out beyond the front of the tube, and the tops about halfway down. The front extensions will provide rails for the radio tray to sit on later.
More next time!
Attachments
Last edited:
Doc James Hammond
Very Strong User
Part II:
AFTER that’s all hard, it’s time to trial fit the assembly into the fuselage. This is where you have to make sure that you know the centre of the ballast mass and the CG of the plane. Trim, phiddle and phart with the assembly until its fits nicely inside the fuselage, while making sure the CG position and the centre of ballast mass are the same! That done, remove a portion of the rail just behind the ballast tube opening on both to run the wing servo wires down. You need this to allow the wires to pass the end of the ballast tube and go into the radio compartment.
NOW glue the assembly inside the fuselage, after checking ad infinitum that the damn thing is in the correct place.
FINALLY, after all is cured and hard as a diamond, make sure there are no obstructions, protrusions, debris, dead mice or any other mummified remains inside and route the wing wiring harness. The wires should fit into the “trenches†either side of the ballast tube and then run down through the removed rail portion into the radio compartment. And if you have done it right, you can reward yourself with a goodly swig of your favorite falling down water.
THAT done, it’s time to secure the connectors into the wing holes. What I do is to drip a little bit of cyanoacrylate glue into a discarded pop/soda bottle cap, and then use a toothpick or sharpened stick to get the tiniest drip of Cyanoacrylate and run it between the connector and the wing stub hole. Damn stuff is hard to control if you try to use the bottle nozzle, and the little nylon capillary tubes that come with the glue never last long.
AFTER that’s all hard, it’s time to trial fit the assembly into the fuselage. This is where you have to make sure that you know the centre of the ballast mass and the CG of the plane. Trim, phiddle and phart with the assembly until its fits nicely inside the fuselage, while making sure the CG position and the centre of ballast mass are the same! That done, remove a portion of the rail just behind the ballast tube opening on both to run the wing servo wires down. You need this to allow the wires to pass the end of the ballast tube and go into the radio compartment.
NOW glue the assembly inside the fuselage, after checking ad infinitum that the damn thing is in the correct place.
FINALLY, after all is cured and hard as a diamond, make sure there are no obstructions, protrusions, debris, dead mice or any other mummified remains inside and route the wing wiring harness. The wires should fit into the “trenches†either side of the ballast tube and then run down through the removed rail portion into the radio compartment. And if you have done it right, you can reward yourself with a goodly swig of your favorite falling down water.
- RADIO TRAY:
THAT done, it’s time to secure the connectors into the wing holes. What I do is to drip a little bit of cyanoacrylate glue into a discarded pop/soda bottle cap, and then use a toothpick or sharpened stick to get the tiniest drip of Cyanoacrylate and run it between the connector and the wing stub hole. Damn stuff is hard to control if you try to use the bottle nozzle, and the little nylon capillary tubes that come with the glue never last long.
Attachments
Doc James Hammond
Very Strong User
Part III:
NEXT I usually make some Depron or other foamy type connector wire keepers to bung inside the fuselage wing stubs to prevent the wires and pushrods from obscuring the wing joiner orifice. Note that these are about 20% larger than the space they have to go into, both are different sizes, and they have channels cut so that each side holds down the wires, etc. well. In this case (see above – I made 2 sets while I was at it) it was bit of blue packing foam.
FIRST MAKE SURE that the Teflon control rod tubes are ON TOP of the wire bunches, then use something thin and flat to hold down the wires and pushrod tubes, and then slide/push the keepers into place each side front and back – a bit farther than the orifice. I used a stainless-steel spatula, but a steel rule works well. Bingo! wires and tubes now firm and secure and not obstructing the ingress of the wing joiner.
NEXT I usually make some Depron or other foamy type connector wire keepers to bung inside the fuselage wing stubs to prevent the wires and pushrods from obscuring the wing joiner orifice. Note that these are about 20% larger than the space they have to go into, both are different sizes, and they have channels cut so that each side holds down the wires, etc. well. In this case (see above – I made 2 sets while I was at it) it was bit of blue packing foam.
FIRST MAKE SURE that the Teflon control rod tubes are ON TOP of the wire bunches, then use something thin and flat to hold down the wires and pushrod tubes, and then slide/push the keepers into place each side front and back – a bit farther than the orifice. I used a stainless-steel spatula, but a steel rule works well. Bingo! wires and tubes now firm and secure and not obstructing the ingress of the wing joiner.
Attachments
Doc James Hammond
Very Strong User
Part IV:
NOW it’s time to get the control rods sorted out. After many years of using carbon rods and plated brass clevis/ball joint leaders, I have come upon the method that works the best for me: First abrade all the surfaces lightly - until they don’t shine is enough. Then degrease the rod and the leader with alcohol or acetone etc., before using Cyanoacrylate glue to secure the leaders to the rods. After that, thread an appropriate sized piece of heat shrink tubing on to the rod and get it back out of the way. Next thoroughly mix up a very small amount of 30-minute at least, (24 hour is better) epoxy and dab a bit round each rod. NOT TOO MUCH!
THEN slide the heat shrink tubing over the assembly and heat it gently with a heat gun (not a flipping cigarette lighter or a blooming blowtorch!) and shrink it until its tight. It’s a good idea to have a piece of tissue or a rag to dab away any escaping epoxy – and there will be some. Neat huh?
This is how I do all my control rods so I won’t bother to repeat this elsewhere in the instructions.
NOW it’s time to get the control rods sorted out. After many years of using carbon rods and plated brass clevis/ball joint leaders, I have come upon the method that works the best for me: First abrade all the surfaces lightly - until they don’t shine is enough. Then degrease the rod and the leader with alcohol or acetone etc., before using Cyanoacrylate glue to secure the leaders to the rods. After that, thread an appropriate sized piece of heat shrink tubing on to the rod and get it back out of the way. Next thoroughly mix up a very small amount of 30-minute at least, (24 hour is better) epoxy and dab a bit round each rod. NOT TOO MUCH!
THEN slide the heat shrink tubing over the assembly and heat it gently with a heat gun (not a flipping cigarette lighter or a blooming blowtorch!) and shrink it until its tight. It’s a good idea to have a piece of tissue or a rag to dab away any escaping epoxy – and there will be some. Neat huh?
This is how I do all my control rods so I won’t bother to repeat this elsewhere in the instructions.
Attachments
Doc James Hammond
Very Strong User
Doc James Hammond
Very Strong User
Part IV
This can be done in three ways:
Remember that the tail stubs and the Tailplanes are not 90 at degrees to the 5mm rods, but ARE at 90 degrees to the fuselage centre line. Extend the holes carefully, using a very slow drill speed and a gently pushed 5mm bit to ease through the fuselage. To make a more secure alignment, I wax the ends of the 5mm joiner rods and insert them so that they can protrude through the bottom of the fuselage. Then I pull them out again, and add splooge through the new holes on the underside of the fuselage.
Then push them back and twist them to distribute the splooge inside. Be careful to remove any epoxy that gets pushed out. When cured you can knock the rods out and shape the ends of the joiner rods to the fuselage contour by carefully sanding.
Note: Using the chuck end of 5mm drill bits, or even better, using 5mm ground steel dowels is better than using the carbon Rods.
Last part V is coming!
Cheers,
Doc.
- V-Tails:
This can be done in three ways:
- By continuing the 5mm hole through the fuselage sides, and bonding the 5mm rods through the fuselage. Problem there is that if you break the rods – which is highly unlikely – then they won’t be that easy to remove and replace.
- By adding a bit of “splooge†(epoxy and filler) around the ends of the 5mm rods where they touch the bottom of the fuselage. Again, unless you wax the ends of the rods or use substitute ground steel dowels prior to adding the splooge, then this again presents a “permanent†solution.
- Belt and braces - combining 1, and 2:
Remember that the tail stubs and the Tailplanes are not 90 at degrees to the 5mm rods, but ARE at 90 degrees to the fuselage centre line. Extend the holes carefully, using a very slow drill speed and a gently pushed 5mm bit to ease through the fuselage. To make a more secure alignment, I wax the ends of the 5mm joiner rods and insert them so that they can protrude through the bottom of the fuselage. Then I pull them out again, and add splooge through the new holes on the underside of the fuselage.
Then push them back and twist them to distribute the splooge inside. Be careful to remove any epoxy that gets pushed out. When cured you can knock the rods out and shape the ends of the joiner rods to the fuselage contour by carefully sanding.
Note: Using the chuck end of 5mm drill bits, or even better, using 5mm ground steel dowels is better than using the carbon Rods.
Last part V is coming!
Cheers,
Doc.
Attachments
Doc James Hammond
Very Strong User
Another one ready to go.
J
JarHeadFlyer71
Guest
Looks great! When is Wayne going to have some of these available?
Doc James Hammond
Very Strong User
Not sure Jar. Best to ask him?
Cheers,
J.
Cheers,
J.
Doc James Hammond
Very Strong User
Part V:
PLEASE DO remember to make up your wings on a soft surface. The paint used for the model is actually hard 2-part car paint so it’s pretty resilient, but we use a lot of hard tools, mini-grinders, and abrasive paper - not to forget the vengeful wife’s nails - all of which can be harmful to the nicely polished wings.
Design notes:
THE WINGS for the Redshift have a very advanced planform that is designed to give a good elliptical “type†lift distribution while minimizing the boundary layer departure problems often associated with the ellipse type wing configuration. Added to that and to make thing even more weird, you will notice that the aerofoil sections are double cusped – that is, as a friend once put it – they have undercamber AND “overcamberâ€. This is a high control response section that is designed to give good reaction to control inputs, so you get more effect for less angle of deflection. Or to make it easier to understand, less drag per given control input/control response.
If you want to know more about this, please contact me.
AS USUAL, all this means penalties, as there is no free lunch. The aerofoils are 8% thick, and have just under 2% camber with the high point at about 25% of the chord – which leaves the rear of the airfoil a bit thinner than “normalâ€.
The end result of this means that for the ailerons, the new 8mm (5/16â€) thick wing servos are easiest to install – and these are in fact what the wing is designed to use. 10mm Servos will fit, but end up being a bit fiddly to install. Here I have illustrated the “worst case†by using 10mm servos in the aileron pockets.
Note: For flaps, 10mm thick servos will be no problem.
Flaps Ailerons
Start by spotting the servo mounting holes on the servo frames – either the ones supplied, or any you wish to use. The drill the correct sized holes through the frames and trial fit the servos, checking to make sure that the mounting screws do not protrude through the bottom of the fames. If they do then just file them off. Sometimes I have found I necessary to file a small clearance on the side of the frames to let the servo wires fit freely.
Note: If you are using 10mm servos you will need to trim the servo hatch mounting area to allow enough room to get the servos and frames in.
TRIAL FIT everything! Make sure the whole assembly fits where it should, and that the servo arms will line up with the control horns. If anything needs to be fettled, adjusted, or modified – now is the time to do it. Also, please don’t forget to roughen the undersurfaces of the servo trays to provide good adhesion.
NOW it’s a matter of degreasing the pocket insides and the servo trays then bonding in the trays with epoxy. I find its best to do them one by one, even if it does take longer as this part is important. Try hard not to get any epoxy on the wing surface or better yet if you are not a lazy bar-steward like me - bung some masking tape down.
In any case its always a great idea to have some alcohol around for a quick wipe.
SERVO HATCHES supplied are too large to fit the servo pocket recesses, so you will have to sand them down to fit. I normally save a little time by snipping off the sides to within a couple of millimeters of the correct size and going from there.
LAST, PLEASE thread the servo connector harness through and connect the servos. To keep things tidy and not too loose I put some Depron “keepers†where I can to hold it in position. Ever since I was a baby I have hated rattles. Don’t be tempted to glue the connector into the wing. It’s hard to get correctly aligned and really not necessary.
Now...a bit of a tidy up here and there, a bit of lead in the nose (remember to glue in the nose weight at LESS than the required weight - they are a bugger to drill out of you find you need less weight) some radio titillation and its off to he Races!
Very best,
James hammond, B.Sc., M.Sc, (Cantab) PhD, (Cantab) DBA, Lighter of dark corners, and all around good egg.
- Wings:
PLEASE DO remember to make up your wings on a soft surface. The paint used for the model is actually hard 2-part car paint so it’s pretty resilient, but we use a lot of hard tools, mini-grinders, and abrasive paper - not to forget the vengeful wife’s nails - all of which can be harmful to the nicely polished wings.
Design notes:
THE WINGS for the Redshift have a very advanced planform that is designed to give a good elliptical “type†lift distribution while minimizing the boundary layer departure problems often associated with the ellipse type wing configuration. Added to that and to make thing even more weird, you will notice that the aerofoil sections are double cusped – that is, as a friend once put it – they have undercamber AND “overcamberâ€. This is a high control response section that is designed to give good reaction to control inputs, so you get more effect for less angle of deflection. Or to make it easier to understand, less drag per given control input/control response.
If you want to know more about this, please contact me.
AS USUAL, all this means penalties, as there is no free lunch. The aerofoils are 8% thick, and have just under 2% camber with the high point at about 25% of the chord – which leaves the rear of the airfoil a bit thinner than “normalâ€.
The end result of this means that for the ailerons, the new 8mm (5/16â€) thick wing servos are easiest to install – and these are in fact what the wing is designed to use. 10mm Servos will fit, but end up being a bit fiddly to install. Here I have illustrated the “worst case†by using 10mm servos in the aileron pockets.
Note: For flaps, 10mm thick servos will be no problem.
Flaps Ailerons
Start by spotting the servo mounting holes on the servo frames – either the ones supplied, or any you wish to use. The drill the correct sized holes through the frames and trial fit the servos, checking to make sure that the mounting screws do not protrude through the bottom of the fames. If they do then just file them off. Sometimes I have found I necessary to file a small clearance on the side of the frames to let the servo wires fit freely.
Note: If you are using 10mm servos you will need to trim the servo hatch mounting area to allow enough room to get the servos and frames in.
TRIAL FIT everything! Make sure the whole assembly fits where it should, and that the servo arms will line up with the control horns. If anything needs to be fettled, adjusted, or modified – now is the time to do it. Also, please don’t forget to roughen the undersurfaces of the servo trays to provide good adhesion.
NOW it’s a matter of degreasing the pocket insides and the servo trays then bonding in the trays with epoxy. I find its best to do them one by one, even if it does take longer as this part is important. Try hard not to get any epoxy on the wing surface or better yet if you are not a lazy bar-steward like me - bung some masking tape down.
In any case its always a great idea to have some alcohol around for a quick wipe.
SERVO HATCHES supplied are too large to fit the servo pocket recesses, so you will have to sand them down to fit. I normally save a little time by snipping off the sides to within a couple of millimeters of the correct size and going from there.
LAST, PLEASE thread the servo connector harness through and connect the servos. To keep things tidy and not too loose I put some Depron “keepers†where I can to hold it in position. Ever since I was a baby I have hated rattles. Don’t be tempted to glue the connector into the wing. It’s hard to get correctly aligned and really not necessary.
Now...a bit of a tidy up here and there, a bit of lead in the nose (remember to glue in the nose weight at LESS than the required weight - they are a bugger to drill out of you find you need less weight) some radio titillation and its off to he Races!
Very best,
James hammond, B.Sc., M.Sc, (Cantab) PhD, (Cantab) DBA, Lighter of dark corners, and all around good egg.
Konrad
Very Strong User
Wow, I love these detailed write up!
I have a question, how do you fasten the stab to the fuselage? I’m now using a draw bar threaded in the end of the carbon pin which is epoxied int the stab. The problem with this is that I need to make a boss at the bottom of the receptacle tube and threading carbon it problematic.
I will say that this draw bar has saved 2 gliders in mid-airs. Far too often a gentle mid-air will knock off a taped on or friction held stab with disastrous effects!
All the best,
Konrad
I have a question, how do you fasten the stab to the fuselage? I’m now using a draw bar threaded in the end of the carbon pin which is epoxied int the stab. The problem with this is that I need to make a boss at the bottom of the receptacle tube and threading carbon it problematic.
I will say that this draw bar has saved 2 gliders in mid-airs. Far too often a gentle mid-air will knock off a taped on or friction held stab with disastrous effects!
All the best,
Konrad
Last edited:
Myself, I rarely make my tails removable. I like to glue them in with some rubbery glue (I use Foam Cure lately) should I need to I can cut the glue joint with some dental floss. I do not enjoy the process of removing a V-tail and have little reason to do so for my normal planes. If I am building a "traveling" glider, I may consider a removable tail. For me this would be a plane that needs to break down to as small a package as possible to maybe fit into a suitcase or similar.
If I do build with a removable tail, I will use a tape. Depending on the weight and strength of the model I will adjust the type of tape I use. For light weight stuff, I am not worried about strength, but weight is the big concern, I may use simple clear tape. For a larger plane, and one that might see some abuse I will jump to the heavier tape: https://alofthobbies.com/wing-tape-for-moldies.html
If I do build with a removable tail, I will use a tape. Depending on the weight and strength of the model I will adjust the type of tape I use. For light weight stuff, I am not worried about strength, but weight is the big concern, I may use simple clear tape. For a larger plane, and one that might see some abuse I will jump to the heavier tape: https://alofthobbies.com/wing-tape-for-moldies.html
Konrad
Very Strong User
Yes, that is my small 2 meter glider, I think it is an Astra. Marketed by Sal at Northeast Sailplanes as the Orion or Omega. I kept damaging the tail as my landing shock loads often failed the tape. Surface goes one way, and the servo and plane another.
My only assembled photo of this ship.
http://www.hippocketaeronautics.com/hpa_forum/index.php?topic=21046.msg213843#msg213843
I have found that the bolted down stab is a bit more stable in pitch.
My only assembled photo of this ship.
http://www.hippocketaeronautics.com/hpa_forum/index.php?topic=21046.msg213843#msg213843
I have found that the bolted down stab is a bit more stable in pitch.
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Doc James Hammond
Very Strong User
Hi Guys,
I'm like Wayne - normally I tend to leave the tailplanes in place for local flying - if I have to travel with a plane I take them out.
On my own designed planes, the tailplanes are a "push fit" on the rods and so they don't tend to come out in flight unless well worn - in which case I rub a bit of cyano on the carbon rods to tighten them up a bit!
For the competition V-Tailplanes I use tape, and I like the PVC electrical variety because it's stretchy, provides the right amount of "Mechanical fuze" as it will break if over stressed, and does not leave a sticky mess on the surfaces.
To be honest I don't like to make any holes in composite fuselages - especially at stress points - unless really necessary, though I can appreciate the "draw bar" idea.
Pics of the Samsara are coming!
Cheers,
J.
I'm like Wayne - normally I tend to leave the tailplanes in place for local flying - if I have to travel with a plane I take them out.
On my own designed planes, the tailplanes are a "push fit" on the rods and so they don't tend to come out in flight unless well worn - in which case I rub a bit of cyano on the carbon rods to tighten them up a bit!
For the competition V-Tailplanes I use tape, and I like the PVC electrical variety because it's stretchy, provides the right amount of "Mechanical fuze" as it will break if over stressed, and does not leave a sticky mess on the surfaces.
To be honest I don't like to make any holes in composite fuselages - especially at stress points - unless really necessary, though I can appreciate the "draw bar" idea.
Pics of the Samsara are coming!
Cheers,
J.
