T/U Frame Fit

[shiney]

After leaving the canopy frame to work on other things I'm now back to it. Everything fits in place well but I'm concerned about the gap between the canopy frame and the deck, I think it's correct from reading ahead but the plans aren't good at this point and I'm concernred about drilling the hinges, is this correct or should the frame sit firm onto the deck ?

 

[Simon Hitchen]

Gap

There should be a 1/8th gap between the canopy frame and the top of the longerons. Dont set the position of anything until you have attached the side portion of the frame to the forward weldment. Then tape 4 pieces of aluminum spacers 1/8th thick to the forward and rear longeron locations. This will give you the correct spacing of the forward weldment to longeron.

Search the plans again. The measurement is there somewhere. I dont have mine at hand at the moment.

Good luck. Once you're done the canopy you're really on your way!

 

[shiney]

Thanks

Thanks Simon, I've seen the part about the spacers and this is what has confused me, I'm not sure if the canopy frame sits onto the forward deck and then the side weldements are spaced higher or whether the frame sits off the deck. I thought the latter and I think that is what you are saying.

Thanks

Martin

 

[Simon Hitchen]

correct

That's right Martin,

There is a seal that will run the entire length of the underside of the frame.
There needs to be space for it. When you get the correct spacing for the side of the frame and join it to the forward weldment the bottom edge of the two pieces should meet at the same level. The side skins will then cover the gap and be flush with the longeron.

Happy to help.

Simon

 

[dhall_polo]

tip: Go find four bars of 1/8" scrap, maybe about 2"x1" in size. Tape two of them down on the aft canopy deck just forward of where the canopy latches go, and tape the other two down on the forward part of the aft canopy deck. Just leave 'em there till the canopy is done.

 

[shiney]

update

Everything is in place, spacers under the rails, skin gap is good and overall frame fit is good but there are a few issues I'd like to deal with before I'm finally satisfied and I drill the hinges;

1).The forward skin is flush with the deck and the aft skin overallps, should I trim aft skin

2). There is a "step" of 3/16ths between the frame and the side rail on the right hand side. I think the only way to bring them into line is to trime the skin which will allow the frame to sit down more, any suggestions on this or should I leave the skin and live with this gap?

3). And finally, the canopy frame skin sits proud at the front end of the deckk line, any builder dealt with this problem?

Thanks everyone.


Martin

 

[robertahegy]

Shiney,

Here are some pics of my canopy frame. The front skin (glare shield) should not need trimming to fit the fuselage. The skin and canopy side skin should just rest on the outside top edge of the longeron and side fuselage skin for a nice flush fit and not overlap the fuselage skin.

You need to use spacers to support the canopy frame rails while assemling the whole thing. I used a seal material on the bottom of the canopy frame to cushion the frame and seal it.

The skins used to cover the caonopy rails needs to be fitted so the edge buts up to the glare shield skin.

Hope this helps,

Roberta

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[Brantel]

Looks like regular tipup madness to me!

Seems most if not all have the same problems that your seeing. No magic cure here.

I would not trim the tabs of the front canopy skin unless you plan on making longer side skirt skins which will require new material.

Your frame is too high in relation to the side rails. The top of the side rail will almost be even with that tab that sticks out of the frame once it is in the correct position. You may have to trim to skin to get it down there but be carefull not to trim too much.

If you don't get these proper, you will have a hard time with the splice plate and wedge spacer.

Like the others say, keep those 4 1/8" spacers in there throughout the process and make sure the side rails are clamped down whenever possible to keep the alignment correct on them.

 

[hydroguy2]

In my short canopy frame experience, until you get the skin and reinforcement pieces Riveted together, the frame will change shape everytime you take the skin on/off. So here's my path.

1. get the canopy skin gap fit as close as possible to the front skin. .020-.032 leaves you adjustment room later.

2. clecos do not pull the skin in tight enough on the sides, so do not shim this area

3. be patient, things move EVERY time.

I fit the side rails to the weldment without the skin in place. notice the tabs are out of position and need to be behind the siderails

finally you'll have a frame like this which you really like the fit, then you'll pull it apart for paint and riveting. Looks great, huh?

except now one side is up ~0.1" Aaargh!

shiney-your cleco clamp on the skin to side rail is hurting your fit. also your skin is not pulled in tight to the weldment and the ears on the weldment need rebent to go behind the side rails

b

 

[shiney]

Tip Up Frame Madness

OK fellas, I need help or I need a quick build frame!

The TU frame was set up beautifully, the 0.20 gap was perfect along the skins and the skin sides sat nicely along the fuse line. 1/8th spacers sat under the side rails and the side rails sat perfectly into position. All taped and ready to go. Drilled the hinge holes and the canopy worked like a treat.

Then I put the struts on and WOW, it all went pear shaped, here you can see there is a 3/8th rise on the skin;

Here you can see that the skin no longer sits on the deck, on the right side it has risen by 2/8ths and on the left by 3/8ths. There is so much spring in there, I push my hand down on it and it nearly goes back into position, but when I release my hand it springs back.

So, I have spent night after night trying to work out just why the struts have had such an effect on the frame.

I tried to reshape the frame but there is only so much you can do when the C614 has been riveted. I filed here, I field there, I moved the aft strut support back 2 1/2 inch in the hope it might releive some of the pressure. Nothing worked. Then I took out the hinge bolts, pushed the frame down, reset it all and got a good fit, with the hinge bracket hole now completely out of line with the guide holes.

I have done EVERYTHING on this frame by the book and to the plans, I have spent a lot of time getting it right becuase for me it has to look great, I can't tell you how pissed I am. I have no idea how this could have happend but it has and it's really demorolised me.

1). How do you think this has come about because I haven't a clue how it's happened?
2). Can I weld the hinge holes in any way so that I can still use this frame?
3). Has anyone else experienced this when puttng the struts on ?


Thanks


Martin

 

[Rockyjs]

Martin,
From your picture it appears the sub-panel and the canopy skin are not riveted! Things change once you rivet. Mine shifted around until I finally riveted the sub-panel, front canopy skin and the frame. You also need to cleco the forward skin in virtually every hole to prevent movement. Remove the struts. They will distort the frame, until the canopy is completely finished! Once riveted if you still have misalignment issues with the hinge you can:

a) If you have enough remaining clearance on the hinge holes. Drill an oversize hole moving it in the direction necessary to correct the misalignment and install a larger bushing with the same center dimensions.
b) You could take the frame and have the holes welded and redrill.

The Tip-up canopy frame is very frustrating to work on. I rate it as the worst part of the build. I ended up shimming the front skin to get a decent fit with some slight canopy skin puckering. In the end it came out fine.

Hope this helps
Rocky

 

[Jim P]

This canopy is absolutly the worst part of the kit, even worse than fueltanks from my perspective. Tippers had the reputation of being easier than a slider, but I'm not sure. I also have a gap between the sides and the longerons which is filled nicely by a seal, with no air gaps there. I also ended up with gaps at the forward edge; the forward edge was sitting higher than the front skin, so shims were put under the front skin prior to riveting. Even so, after riveting, I ended up with the canopy forward edge protruding above the forward skin. Now I'm doing some fiberglass fill work on the skin. Every one of these fits different and you'll just need to work it as you assemble for the final time.

 

[Finley Atherton]

I had the usual problems with the fit of the frame and skin changing every time I proceeded to the next construction step. I also managed to mangle the canopy skin when it caught on the fwd. fuselage top skin after installing the struts. In the end I replaced the entire canopy skin with a new sheet of the same type of aluminum purchased from the local airport. This turned out to be a quick and cheap solution. With the old skin in place I added masking tape at the edges to "fill in the gaps". I then used the old skin with the masking tape as the template to cut out and match drill the new blank sheet of aluminum. If I ever had to build a new canopy I think I would do the same again by considering that the original skin is a sacrificial item to be used to ultimately get the final second skin fitting perfectly.

Fin
9A

 

[shiney]

in summary

Thanks for your comments fellas, all are appreciated. I have now sorted it out and it looks a whole lot better, in fact, very nearly perfect and I am once again a happy and content builder!

What I have found with this T/U thing (and this is only a personal view) is that the Vans instructions are no where near adequate to get this thing to fit properly. There is so much "tinkering" to do, it must all be done BEFORE the hinges are cut.

So in summary, if I was to do this again, I would not drill the hinges until I had set the frame in position WITH the struts attached. You can then set the strut stops, which in turn get the frame square (because the struts pull it all over the place) before drilling the hinges.

Once again, many thanks.


Martin

 

[allbee]

wait until you drill for the locks in the back. You get everything working good than you bolt them in place, than it's back to square one because nothing works right. It's shave a little off here and there until you get it right again. Yup, I put my struts on and everything changed, I just went with the flow and said, ok, a little more gap there. So you change something somewhere else to make up for the previous. Before you know it your done. Maybe...

I threw Vans instructions a long time ago.

 

[shiney]

Thanks Steve,

I've joined the "we evantually got it right" T/U team. It took time, it took and it nearly robbed my gumption, but in the end it looks as I want it to look.

Thanks


Martin

 

[shiney]

Innovation ?

Has any one seen this?

http://uk.youtube.com/watch?v=sBIEPzC9G1s

 

[allbee]

wait until you drill for the locks in the back. You get everything working good than you bolt them in place, than it's back to square one because nothing works right. It's shave a little off here and there until you get it right again. Yup, I put my struts on and everything changed, I just went with the flow and said, ok, a little more gap there. So you change something somewhere else to make up for the previous. Before you know it your done. Maybe...

I threw Vans instructions a long time ago.

Yup, thought I was a smart one because I had my back locks great. Put them in final and nothing worked. I ended up taking a drill bit and sloting the holes a little to give a little slop, now they are good. That's what I've had to do with the whole canopy, make things fit, what a deal.