David Matin

First parts from the machine shop have arrived. unfortunately I’m heading to a big model event next week so all my of effort is going into getting ready for that.

Your quite right, I was at work when I said 66mm, when I got home I measured that was the first tailwheel I made and saw it was well under sized. This is a picture of the full sized tail wheel a work colleague had and brought in for me to measure up. 150mm/6in rule for scale. Note the tire is totally wrong. he guessed it has come off a sea fury or similar. So you are going to need a much larger fork!

Not a bad solution but it will only accept a 50-55mm wheel, The scale wheel size is 66mm and its quite a square wheel shape so a fair bit larger fork would be required. Also you have to engineer a way to make that steeable becuase those plate are normally used when the leg is mounted to a retract unit.

What size of wheel can you fit to that fork?

Thank you. Just hoping I have a nice lanc to fly at the end of this build

I have a work mate with a few spare, but i don't have a steel ball or a glass one, so just using what I have available. The tops and especially the undersides of the 3D printed parts are not always the smoothest, so the bearing is there so the only friction will be the walls of the prints rubbing past each other. That will be enough friction. The weight of the bearing will be negligible compared to a steel ball or a glass one. he end goal is to not have the weight of the servo in the tail, as Mr Mcintosh has suggested None of the information I have seen about free castoring tailwheels had differential brakes available to them. Nor did they have a gyro assisting with keeping the model straight, so no one can tell me if it will work well or not. Its no loss to test if it will work. The model is going to the field for taxi testing either way and so if it doesn't work, It's not like it will be waiting 12 weeks for parts, I will design a steerable unit and by the next trip out it will be done. No big deal at all.

It's been designed around the thrust bearings that are used in Helicopter blade grips. Trex 700 to be precise

A far more developed tailwheel is now completed, and the first parts have started rolling off the printer The plan is that this will be a sprung, free castoring tailwheel. There are a few items not clear or missing from these drawings. namely that the tailwheel fork is retained into the spring housing via a pin and slot. I have added an arrow where the spring will be housed. then this whole assembly will be allowed to rotate within the castoring housing, and there will be a small thrust bearing in the top cavity to ensure smooth movement under load. Everything I have read on a freewheeling tailwheel on an R/C model is not great but I have a way of modifying this setup so that it can then be controlled by a servo If needed.

Spend a few hours today designing up the tail wheel assembly. I still have to design how it will mount onto the airframe, but at least this will let me do some test prints and see how it looks in position. before I get too much further along in the design.

Yeah ridged mounting the entire exhaust is a recipe for damage, so my idea with the silicon joiner is to give the system some flexibility to absorb the vibrations. I've also used aluminium tape to good effect in the past to shield from heat, and I've also used ceramic heat shielding paint in the upper sections of my 1/4 Fw-190 cowl to do the same job, so some options there. My preference is straight out though so I'm minimising the amount of heat within the cowl. the pipe would only be about 25mm long so a very short run. The test airframe to get some flight time into the saitos before the go to work on the Lanc is nearing completion, so we can do some real world testing of what muffler-less operation sounds like hopefully in the next week or two. And the machine shop have finally started on the more complex landing gear parts. once they complete those, I will have to start working on the other parts on my lathe at home.

ummm interesting… thanks for the heads up. my plan C was to just go straight out the side of the cowl With no muffler, but until I do an engine run and see just how loud it will be I don’t want to commit to that option. Everyone says saitos are quiet, and my little .56 four stoke is really quiet, but these gassers are a different beast. I could also line the firewall with 0.010” aluminium sheet to help deflect the heat. @martin, I’m supprised the Teflon melted? I have a Teflon joiner for the tuned pipes on an Edge 540, with a DLE 55, and no problems there.

They have a long, well documented history of failing. At least the saito ones do. Also from a flow of gasses perspective, They are not great. I work with a guy who is a qualified aircraft welder so this will be a great opportunity to finally learn to TIG weld.

Been toying around with different versions of the exhaust for the saitos and this is the one I have settled on. I really do dislike seeing mufflers hanging out of scale models it so handy to be able to print parts to model what they will look like before committing to making them. In this case they will be made from 12mm mandrel bent stainless steel tube with a silicone joiner to allow for easier disassembly

Reached the point where the design of the wheel hub has been frozen and the flying version printed. On the inboard hub I have added a recess for the brake assembly and the steel brake disk drive dogs slot into those 3 holes. They are also the attaching screw holes so the hubs are screwed into the tires first and then the brake disk is inserted. I find that it normally take 3-4 prints of the tire to get one that I am happy with, so once I had a good example. I made 3 of those. I like to have a spare especially in the early days of a new model just in case the design needs some tweaking . the TPu printed wheels will go through what I would term an extensive post production process to get them looking like tires. The printing of the final scale exhaust hubs is also underway with just one more set to come off the printer

The landing gear design was start a fair while ago, and it has been slowly progressing as time allows or the decision making process needed me to develop it further, like the final tire sizes were done some time ago, but one decision I still needed to make and couldn’t really delay any further was between the electron ER-40 and the ER-50 retract units. their sizes are quite different and I want sure what would fit. luckily their website has engineering drawings so I modeled both units and this then allowed me to see what would fit best without a penny leaving my pocket 😄 In the end with the fuel tank installed in the inboard nacelle, the ER-50’s proved to be too big, so the 40’s were ordered. the first test print of the wheels were also done. I find it takes between 3-5 prints of the tires before I get the right balance of firmness.

Payneib is correct, The saitos I'm using are 17cc Gas motors so about .90-100 glow 4 stroke equivalent. Power is not something I expect to be short on other than if the 3 blade props rob too much power but honestly I was going to buy the 14cc version, but elected to purchase the 17cc so I could spin that size prop. 12kg is a great weight! A modeling buddy's last TN Lanc has tipped the scales at 24kg 😮, Flies around pretty well he tells me.

I don't fly at night too often..... 😆 There are the port, and starboard wingtip lights, the landing lights in the port wing that retract and the 3 IFF lights under the rear of the fuse that i'm aware of. Other than for landing I wouldn't imagine the crew during wartime would have been in a hurry to turn any of them on. But the actual response is I had to choose my battles if I ever want to get this model finished. I will probably come back and re-visit the wingtip lenses at some point.

You can see some of the steps on the build thread here: I do use it over automotive acrylics. The glossier you can shoot your base colours down onto the airframe the easier it is to work with the oils. The oil paint takes a good 4 days to dry. this means that you have 2-3days dependent on your weather conditions where you store the model to play around with it to get the final finish you are after. The picture I posted was just the first of 4 colours used to make the exhaust staining on the Lancaster. I had to wait 2-3 days for the black to cure enough to allow me to come over the top with the next colour. This is only true if you was visible variation between the colours. if you want them to blend in a little more do it the next day. Once its dry I would highly recommend clear coat for a number of reasons. firstly it will seal and protect the oils from handling damage over time. second and more importantly, the clear blends in all the colours to make a more homogenous finish. it really completes the picture in my eyes and also allows you to finish the model to the sheen you are after. I shoot an automotive 2-pak clear coat because I love the hardness and durability of the finished product but this might not be within everyone ability to play with. There are other great products out there that give you a similar finish. I'll try post some other pictures of models I have completed.

A quick print of the landing gear I’m designing to see how the overall sit of the model will be and a good thing I tired because I ended up cutting about 1.5” out of the overall length. the blue wheel is the solid test print of the tires I will 3D print for it. The tire will be a flexible TPU material and the rim will be an ABS. I’ve run 3D printed rims and tires on my 1/4 17kg FW-190 for 3 years now so this should be no challenge for a similar weight Lancaster

I have moved away from airbrushing and now use artist oils for the majority of my weathering. Love the control and the ability to wipe it all away and start again, and you also get about 2-3 days to adjust it to your liking. There are many techniques to achieve weathering, but my saying is there is no wrong technique, but there is a wrong outcome. So try a few of them and use what you find the easiest to get the correct outcome.

With all the painting done I can move to installing all the fuel tanks, throttle servos and motors. quick little 3D print to keep foreign objects from going into the exhaust of the saitos while I work.

Thank you Richard, Just hoping I finish up with a nice looking and flying Lanc

With the wings cleared it was time to check where the CoG was at so far. while it was in the living room wifey manages to snap these pictures. Unfortunately it was a little too dark to get really good detailed shots but she is looking fairly complete in these pics

Two of my favorite pics of the Lancaster so far, and then the one is just sizing up the crew figures to suit the pilot seat