The P.1121 get's it's feet wet

[Gondor]

More metalwork mayhem.

I started by tinning the inside of the ends that would fit onto the short uprights. Then I used my files to make sure that they would still fit.



That's good  :thumbs-up:  Right, add solder next. One section at a time.



Second section added





Yes, it's a bit messy, but it will be hidden, and I think I may need to upgrade to a blowtorch to get the solder to flow correctly. 

After a bit more work





And overlayed on a set of plans



The plus signs show where frames Two and Three are, and where the centre of the wing, front to back, crosses them. That is where the next holes are to be made, and where sections of smaller tube will go through.

This is probably way over-engineered, but I can't think of any other way to do it, other than to use plastic. I thought the brass would be a bit more robust though, and carry more weight.

Gondor

[Rick Lowe]

If something's worth doing, it's worth overspecing...

[NARSES2]

If something's worth doing, it's worth overspecing...

 

[Gondor]

Roughly two months to Telford, and I am starting to get worried as there is tons still to do.

I have managed to drill the start holes for the two almost uprights from the keel. I reckon that there is another four, possibly six more to do then plastic can be hung onto the frame.

Gondor

[Gondor]

More progress.



First one cross piece fits into the near vertical member, then the second.



Next, I have to braise the parts together and get the position of the new parts exactly symmetrical to the keel. Lots of fun to ensure this happens.

Gondor

[Gondor]

Oh Poo!

Ten days since my last progress post on here, not good now that we have just under eight weeks until Telford.

I have finally got something worth posting about. In the previous post, I had made the holes for the cross members at wing frames two and three. This afternoon I braised them to the existing frame!









Knowing my luck, I have probably fitted the front one to the rear and vice versa. My technique is getting better as well I think. No removal of excess solder this time. The next step is to mark out and make the holes for the cross members to go into. The longerons, for want of a better descriptive term, will provide support not only for the cross pieces, but they will also be behind the internal skinning I have done for the wing roots. The ends of the longerons will also help tie some of the internal structure together that is supplied in resin. I will be using epoxy for that part.

Gondor

[NARSES2]

Soldering looks good    When I did soldering at school the world price of tin went through the roof 

[Gondor]

The last set of holes have been started.



Three on one side and two on the other. The three holes are on the outside, and the two holes will fit over the cross members I soldered in place yesterday. This is due to the extra third hole being exactly in line with the forward resin frame fitted to the main undercarriage bay. Cutting a couple of slots out of their sides for the longerons is not a problem, but for more brass similar to the other parts I have soldered together, it's a very big problem.

I have already started expanding the holes with a square file. This may take a day or two's worth of filing as its a total of ten holes to make bigger, and in the right places.

Gondor

[frank2056]

It may be a bit late - but use a non-acid based flux (even if the solder says it has flux) to make the solder flow better.

[Wardukw]

Very nice work Al ,,,  
As Frank mentioned about helping the solder to flow ,,i use a stuff called Duzal ,,it makes any solder flow and ya get fantastic results even tho it can be a wee bit messy ,,its a life saver with the amount of soldering i've had to do at times .

[Gondor]

The brass work is just about finished. 

This is where I had got to yesterday.



Today I made the holes big enough to fit onto the cross members.



And now they are lightly soldered in place, and only on the tops for now.



A month to the day that I posted the first step in this part of the build. I am so glad it is effectively over!

Gondor

[Gondor]

Arrrrg   

A quick check to see how the frame fits the fuselage, and I find that some of the frame is too long   



The white is the inside of the right-hand side of the fuselage. The nose will be to the left and the tail to the right. The grey part inside the fuselage on the left, is the nose undercarriage bay. The upper arms, longerons, are too long on the left side of the picture, as they would go through the frame that holds the engine compressor face. The keel is too long in the opposite direction and intrudes into where the main undercarriage bay is to go. The longerons are supposed to sit on top of the main undercarriage bay and help provide structural strength.

In the picture below, I have marked where the relevant sections need to be cut.



The good thing is that they are too long, rather than being too short.

Gondor

[Old Wombat]

All this metalwork!   

You may as well skin the thing in aluminium & be done with it!     

[Spino]

Was wondering when we would get to see something other than square metal tubing on this thread again!  Vacform stuff has always been too much for me, for exactly this reason.  You have to construct a frame to support the whole thing, from the inside!

[Gondor]

Was wondering when we would get to see something other than square metal tubing on this thread again!  Vacform stuff has always been too much for me, for exactly this reason.  You have to construct a frame to support the whole thing, from the inside!

The last one of these that I built was OOB. I am building the frame for this one because of all the hacking about the fuselage has taken and the fact that the wings need to be folded. Vac-form kits usually just need tabs on the inside of the edges rather than pins in injection kits.