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Author Topic: Donald Campbell's Bluebird K7  (Read 53562 times)

Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #100 on: November 10, 2014, 09:09:54 PM »

Hi George. The battery is there for the moment because that's where it needed to be on Mk I to get the CG right. Later on when the whole structure is modelled, I will be able to get an fairly accurate prediction of the CG from the computer (I'll have to make some guesses when it comes to weight of the waterproofing, paint and glue). I can then look at moving the battery if need be. Actually, it's not hard to get the battery in and out on Mk I but I shall design in a proper sliding drawer for it so I don't have to pull it out by the wires  >>:-( (if it stays where it is  ;)) If I go this route, the ESC will be hung from the hatch to keep it out of the wet. Not that my boats ever leak.... {-)

Now the booms. Yes, I did read your earlier advice. In this model, however, the booms are not going to be connected to the outer hull except by a little silicone sealer. The load is taken by the box between the inner frames. The box will be extended to meet the hull (to keep the water out) but between the frame and the hull skin it will be in clearance. I'll cover the details of my proposed arrangement in a later post.

Yeah, I have a bit of a weird approach but I see the functional structure in my mind and the hull sort of hangs off it. Quite the opposite of starting with a hull and building everything off that. I take all your comments on board and I'm still prepared to be shot down in flames later but I think you will understand my strange logic as the post progresses.

Just finished correcting the model of the cowling. That was hard work! Too late to post tonight but it's the next topic for discussion.
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Ramon

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Re: Donald Campbell's Bluebird K7
« Reply #101 on: November 10, 2014, 11:06:29 PM »

Tim - Can I just say that I find your detailed accounts of your thoughts and the reasoning behind it makes for interesting and informative reading. I fear I will have little to add but if I may make the following comment.


As a regular poster on another forum sometimes, when one sees the number of visits relative to the number of replies, it can get a bit dispiriting if you begin to feel you are talking to a vacuum. So, speaking for myself - I know I won't be having much to say nor likely to have much input but I do know I shall be following you every step of the way - you're doing a fine job  :-))


Regards - Ramon
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #102 on: November 11, 2014, 08:12:39 AM »

Thanks Ramon. I'm not concerned about the ratio of views to replies; I read a lot of other posts and just admire the work. A lot of them leave me speechless anyway - the craftsmanship is staggering! When the comments come in, they are always helpful and welcome.

I was thinking about what George said on batteries last night  (this modelling lark tends to take over a bit!). I'm using a 5000 mAh battery. If I find that I want to spend longer on the water I think I might invest in a second battery but swap them over mid-session rather than carry one round in the boat - I'm aiming for low weight after all. On the other hand, if the battery stays where it is, which depends on where the CG comes out, there is enough space between the existing battery and the motor to drop another one in. (I have designed the boat so that the battery slides back into that space to be removed and also so the battery position can be simply adjusted to get the balance right). Guess what? If I add a second battery just in front of the motor, it will be sitting right on the CG. No major re-trimming needed.

Of course, I planned it that way....... {-)

I haven't run the boat long enough to flatten the battery yet. Only time will tell what course I take. (Bit like my steering).
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #103 on: November 11, 2014, 10:37:54 AM »

I mentioned earlier that I'm going to split the cowling right down the boat. On Mk I the cowling was an integral part of the hull. That made it difficult to build, made the
model extremely diffucult to handle during the build and made access to the inside a nightmare, especially round the transom when I was going through a series of modifications such as moving the prop strut around. The rattling sound I hear when I pick the boat up now is all the lost M3 nyloc nuts floating around in there.

My approach on Mk I was to plank the frames with balsa strips, about 15 mm wide. I used CA glue and quickly learned what you all know already. The glue lines were harder than the wood, which made it very difficult to sand the skin smooth. I didn't use any stringers either so there was a tendancy for the skin to balloon outwards where the curves got tight. To this day, you can still see a slight 'barrel' effect (flat patches) when the light catches the cowl.I used a lot of glue and filler on that cowl, which may go some way to explaining why Mk I is, like her builder, a bit heavy in the rear end.

'Make it from fibreglass', I hear you shout. No, that's not going to happen. I hate the smell, the mess and the feel of fibreglass. I've never made any good out of it. I enjoy
working with wood even though I'm not very good at it. Why use a material you hate when a hobby is supposed to be fun?

My plan for Mk II is this. I will cut the frames out as per the picture, mark out the final hollow shape but leave them solid for the moment. The frames will be assembled onto
a sturdy 'spine' sticking out of the bottom (not shown) that I can grip in the vice. The 1/4" square stringers are not 100% accurate in the CAD model but are close enough for
the CG calculations.I want to be sure that the join between the removable cowl and the fixed part is good. There are two sheet stringers shown in red and green in the picture. They will be glued to the frames but not to each other. In fact, they will be separated by the thickness of a knife blade. (I've got loads of blunt ones to use as spacers - never throw anything away).These lie on the split line. Below that there is one last stringer shown in orange. This one is curved in both directions and is the line where the cowl meets the deck. (Once again, the power of CAD allows me to extract that weird shape from the solid model easily).
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #104 on: November 11, 2014, 10:42:41 AM »

I am hoping to skin the frame using quite large sheets of 3 mm balsa, joining them on the stringers (chubby orange peel segments, if you like). The curves are not too severe
and I hope that with some steam or soaking and a lot of patience I can persuade the wood to take the double curvature. I can work out the shape of the segments by measuring off the curve length round the frames and create a flat pattern for each peice. I will then fit the peices to the frame one by one (but not glue them) and form them to shape before final trimming. I won't glue the skins on until they have had a chance to settle into their curved shape and have dried completely. I don't want to build a lot of
stress into the skin and have it springing off. This is going to be a slow process and I will start the build with the cowl so that it can be drying while I get on with other stuff.

If anyone has experience of this style of build and can pass on any tips, I'm all ears.

I intend to treat the skin and frames to a dose of Ronseal Wood Hardener. Yes, it does exactly what it says on the tin! Originally intended for rescuing rotten wood, such as
window frames, it's a water-thin polyester resin that soaks into the wood and sets rock-hard.It strengthens the wood (you end up with wood reinforced plastic instead of glass
or carbon RP), it repels water and gives a good surface for sanding. It should help keep the cowl in shape over time too. This time round, I will use it sparingly - it does
not evaporate so it adds to the weight. I used loads on Mk I and the structure came out heavy. I also recall it caused some problems when I applied Zap-Poxy to the hull before painting. The epoxy went off much too fast. (What I can't remember is whether this was a reaction on the dried surfaces or whether there were traces of wood hardener in the pot I used to mix the epoxy. I will need to check). 

The skin will initially continue beyond the deck stringers. Once it is all glued up, shaped and sanded, I will trim it back to the deck stringers and cut back the bottom of the frames to their final shape - they will now have legs between the split line and the deck stringer. I will adjust bottom of the cowl to fit the hull. This isn't a super-critical fit because there will be a fillet of filler added later at that joint. The next stage is to cut through the skin from the inside at the split line, leaving the frames intact for the moment. Now you know why the stringers were spaced apart (if you hadn't already worked that one out). I used a similar approach on Mk I to create the access hatch and it worked well. It keeps all the curves smooth.

The whole thing then gets glued to the deck and when it's all set, I cut through the frames with a razor saw from the outside (using the cuts in the skin as a guide). I'm doing it this way to make sure that the fixed part of the cowl doen't spring out of shape and everything is perfectly aligned.

The final stage is to cut out the centres of the frames in the detachable cowl using a Dremel (and put it in a safe place).
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #105 on: November 11, 2014, 10:44:36 AM »

The fixed part of the cowl will be trimmed up on the inside so it's all nice and tidy and the radius between the deck on the cowl will be formed with filler. The curve is far too tight to make from bent wood and the weight of filler required is minimal.

Next topic will be the booms. Bet you can't wait  {-)
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Ramon

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Re: Donald Campbell's Bluebird K7
« Reply #106 on: November 11, 2014, 06:44:46 PM »


Tim - Re the method of covering the cowl - 'Moulded balsa' has been used very successfully to shape complex compound fuselage halves. The balsa is soaked in hot water (ammonia used to be added but is now apparently difficult to obtain - besides it smells awful) and then carefully wrapped to a 'buck' or former using soft bandage. Left to dry, the balsa will retain the shape providing a very strong but very light component.
I Googled 'Moulded Balsa Fuselages' and found this [size=78%]http://www.clapa.org/windy2.htm[/size] - it's by someone considered in the control line aerobatic world to be an absolute master at it. Unfortunately there are no images but further searching will reveal the idea.


I know you said you do not want to go down the fibre glass route but if something like this type of balsa shell is covered with the very lightest F/G cloth say .6oz/sqyd it becomes immensely strong and very water proof. You do not have to use F/G resin - I have used two pack resin fuel-proofer to put this on with which works just as well. You can also use the thin epoxy vailable for the same purpose. The cloth is laid over the finished balsa and the resin gently painted through it with a flat soft haired brush working outwards all the time from the high point. The good thing about using fuel-proofer is that the pot time is long but the dry time is relatively quick. It will be much lighter that using the wood hardener I'm certain.


This is a technique used by many yacht hull builders - a search on here will produce the results.


Hope that's of use - Ramon
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #107 on: November 11, 2014, 07:27:06 PM »

All 'ammunition' is welcome Ramon! It's lodged in my 'things to try' department. Thanks!
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #108 on: November 12, 2014, 01:20:29 PM »

BOOM!

Did that get your attention? We come to an interesting area of the design that has developed round several things:
1)   George's operational experience
2)   My build experience from Mk I
3)   A bit of engineering
4)   How the prototype worked

In Mk I, the booms were made up as wooden U sections reinforced with aluminium tubes held in with fibreglass (yeuk!). The booms were fitted into a box in the hull and then the sponsons were attached. Finally the booms were built up with block balsa to give the final shape. One area of the build that gave me a lot of jip was trying to blend the booms into the hull and sponsons. I used a fair bit of filler but it was all inaccessible for finishing. In short, I made a pigís ear of it and I was never happy with the result.

Now, Iíve said before that I see the model in my engineering mindís eye from a slightly different perspective to others. The prototype boat had a structural space frame inside and everything hung off that. My model is somewhat similar. There are two big beams running the length of the boat and the booms attach to that, not to the skin of the hull. For the structural part of the boom, I am planning to use some 15 x 25 x 1 mm thick aluminium tube I found in the garage (an old shower curtain rail). To be honest, you could substitute a piece of wood here, perhaps spruce. It would be plenty strong enough and only weigh a few grams more (I checked!).
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #109 on: November 12, 2014, 01:52:26 PM »

The booms are going to be fitted after the model is painted.
Really??
Yes. I want to leave the hull as clean and accessible as possible for sanding and painting. Iím not very good with a paint brush and Iím an absolute menace with a spray can. I need all the help I can get! (I hope to get the hang of using an airbrush by the time I get round to painting this model but we will have to see). So how is that going to work without getting glue all over the boat and still make a good joint?

Cunning plan. The weight of the boat is carried by the top of the boom, so that is the bit I need to attach to the frame. The structural box (between the main beams) has a flat top and is deeper than is needed for the boom to fit. The bottom face slopes up towards the centre on both sides. Between the main beams and the hull, there is another box, 1-2 mm bigger than the boom all round. Slow-set epoxy is applied to the top face of the boom where it fits the box (with a smear on the sides too) and the boom is then slid into place across the bottom floor of the box so the adhesive is not wiped off. The ends of the boom are supported on level blocks and the hull allowed to drop onto the top of the boom, maybe with a bit of ballast for good measure. The whole lot will be trued up and checked then left to set. So far so good. The boom is attached where it needs to be attached but the joint is a little vulnerable. Adhesives are good in compression (thatís how it is being used here) and pure tension, good in shear (if the boom tries to slide out sideways) but much less strong in peel and cleavage. If I were to push down on one end of the boom while holding the hull still, the adhesive would be put under a peeling/cleavage load and thatís a likely fail. To get round this, after the epoxy has set, I will insert two glued-up wedges under the boom to make sure that this loading condition canít happen. So thatís why the box floor slopes!

We still have the Ďoversizeí boxes open where the boom comes out through the skin. I will apply a little low-modulus silicone sealer to seal this area to keep the water out, though itís not strictly necessary. The booms can flex all they like now and not transmit any significant force to the hull skin.
There you go, George, I was listening!   :-))

Instead of sheathing the booms in place, I am going to make up some cuffs that slide over the tube. They will be pre-painted to and only attached to the hull by a little silicone. (If I glued them to the hull, I would Ďshort circuití the silicone gap round the structural booms). Iím not going to try to blend these into the hull or sponsons, just make them a neat fit. Oh dear, that requires some skill so it will take a long time.

The sponsons will be fitted in a similar manner. In this case though, itís the bottom face of the boom that gets attached to the sponson structure and there will be a wedge above. That wedge will have to be part of the Ďcuffí. Oh dear, oh dear. More accurate building needed. I have some reservations about the attachment of the sponsons; itís quite a small joint to rely only on adhesive. I will make a judgement when I see the sponson structure. I could add a dowel down through a hole in the top of the sponson and patch the paint up afterwards if necessary. On the other hand, if there is a crunch, it would be better to have the sponson fall off rather than rip the whole side of the boat out.

The pictures below speak more than my thousand words.

I now have a lot of design work to do so please be patient. Eventually, I will get some good predictions of the weight and CG out of the solid model and then it's on to the drawings so that I can cut real wood!
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Mad Scientist

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Re: Donald Campbell's Bluebird K7
« Reply #110 on: November 12, 2014, 09:06:30 PM »

Thanks for sharing your design process with us, Tim. I, for one, find it fascinating! :-)

Tom
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Ramon

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Re: Donald Campbell's Bluebird K7
« Reply #111 on: December 07, 2014, 11:38:43 AM »

Hi Tim - any 'latest news' on the design work ?


Ramon
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #112 on: December 07, 2014, 01:53:03 PM »

Timely enquiry, Ramon; I was planning to post today.

Unfortunately, this project is currently stalled - NOT abandoned. I'm not sure if time is accelerating or my brain is slowing down but I have no spare time whatsoever at the moment! Changing computers seemed to take about three weeks, changing phones a whole weekend...... Mrs M has decided to make up for the schooling she never had as a child and she's studying ferociously every evening. As a one-time teacher, of course I get the privilege of helping. To cap it all, I am changing jobs in the new year, which means going back to a daily cross-Solent jaunt. (That's the second to last thing I wanted to happen. The last thing I wanted to happen was to find myself suddenly out of work, which was looking like a real possibility. Better to jump ship when the water's reaching the gunwales, I say).

I did manage to make some progress on the sponsons. The picture below looks simple enough but belies the work behind it. Just a soon as I get the time, I shall carry on working on the frames till I get to the point where I can pull of the drawings, then find a big printer. I will publish the drawings too as soon as they are done. Good chance I will get a few hours over Christmas but you never know round here!

Realistically, It will probably be around Easter before I get round to cutting wood, depending on how the new job goes. I've been told that I won't need to travel much but I've heard that one before!

So, don't despair! Mk I will be back in the water when the weather (and daylight) permits. Mk II remains a work in progress, albeit slow progress at the moment.

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Ramon

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Re: Donald Campbell's Bluebird K7
« Reply #113 on: December 08, 2014, 06:14:43 PM »

Hi Tim, Sorry to hear that the dreaded work has got in the way - know (or rather, knew) what that was like but the joys of retirement has seen that banished forever now :-))


A thought on the sponsons - would there be any advantage of bolting them on in such a manner that their angle of attack and possibly their height was variable in order to establish optimum position? Might require a small amount of metal work but would be glad to help if you thought it might be beneficial.


Glad to hear it's not abandoned - Ramon
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #114 on: January 18, 2015, 07:43:39 PM »

Happy New Year chaps!
(Chaps includes those of the feminine persuasion, just so as to avoid offence!)

There has been a little progress on the CAD work. Extracting all the parts from the solid is a fairly painful process but it just has to be done.
As things stand, the CAD model predicts a weight of around 2 1/4 kg, including the motor and battery but no prop strut or rudder and no allowance for glue and paint. At least it's starting in the right ball park. The CG comes out just a few mm forward of where I want it. That will move back when I add the prop.

One of the pictures shows two hatches; one in red and one in purple. The purple section I will sheet in and secure with silicone once I am happy with the work round the transom. The red hatch is the watertight access. Another picture shows the removable cowl (not watertight at all).

I thought About Ramon's comment about adjusting the sponsons. Normally, I would built in adjustment but in this case it's not practical because there is no space. I have done the tuning on Mk1 so I'm pretty confident this version will run OK. If push comes to shove, I'll adjust the planning shoes.

Not much of a post but at least you know the project is not dead. Must dash - Mrs M will be home from work in a minute and wanting her dinner!
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #115 on: July 05, 2015, 02:01:18 PM »

Long time no see. Hope you are all fit and well  :-))

By now you would be forgiven for assuming this is just another fly-by-night abandoned project but finally, after six months of chaos I found a couple of hours to sit down and look at the CAD model. I was a lot further down the line than I realised. My original idea was to produce proper, commercial standard drawings for every part so that anybody else could build the model. I realised that not only would that entail a huge amount of work, it wasn't necessary. Instead, I have taken sections through the assembled model to produce the cutting templates I need. I will produce the others as I need them. If anybody else wants to have a go at the build, you have the same information as me. It is, after all, a scratch build. Some things will be worked out on the fly. (Oh, if anyone wants a copy of the solid model - stp or iges, let me know)

I've uploaded the first three drawings. One shows the details of the cowl, one shows the main hull frames and the third is a general assembly. I've managed to get the frame drawings so they will print 1:1 on A3 paper; should be easy enough to get that done by a shop if you don't have access to an A3 printer. If you want to print the GA, you're going to need an A0 plotter! We have one at work, I just need to creep round the right person........ 

And just lookit what arrived on Wednesday  %% along with a couple of shiny new router bits for my Dremel. Yes, it's now Sunday afternoon and  I've have only just found time to open the parcel. Such is life round here. That's a lot of wood for one Bluebird but I decided to buy ahead for this and the next project. The delivery cost was about 15% of the order, even delivered to work on the mainland. Delivery to the IOW would add an extra 20 quid! The filler? Not that I ever bodge anything.... the design actually calls for a bead of filler along the cowl-hull joint so I got a proper lightweight one while I was ordering the wood.

The cowl gets built first. Far and a way the most complicated part of the build involving 3D forming of the skin, which will need plenty of time to dry out. Never done that before so it could get exciting.

I would like to say I'm off to the cave now to start tracing the frames onto ply but I haven't printed the drawings yet so I guess I'll have to do the ironing instead. >>:-(. I'll keep a photo log as I go along and keep you posted. I can't do a Krishna (I LOVE those foam and scrap boats!!) and produce a model every day but we should see some progress now. Watch this space (but don't hold your breath).
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Re: Donald Campbell's Bluebird K7
« Reply #116 on: July 05, 2015, 05:08:12 PM »

Hi Tim - Pleased to see you back on this. I know exactly how it is -I'm having a break from my launch too  :-)

My offers still good on the mount - not doing any machining at this precise moment but keep me in the picture as to when you need it by at the latest.

Looking forwards to the build - I'd love to do one myself but have more that enough waiting to do as it is - nice thought though ok2

Regards - Ramon
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Re: Donald Campbell's Bluebird K7
« Reply #117 on: July 05, 2015, 05:09:08 PM »

Hi Tim, I am glad to see you back I have followed this from the beginning only the other day I was wondering if you was continuing with the build.

Keep the pics coming, I have just down loaded your PDF's I have no idea what to do with them as I have never built from scratch but you never know there is always a first time.

Kelvin
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #118 on: July 05, 2015, 05:32:53 PM »

Back so soon?

Half way through the ironing I remembered that I was going to draw all but two of the frames onto the wood rather than trace them. They are all circular, except the front two. I only needed a couple of dimensions for each frame. I should have put them on in the first place as a check (you can't be sure a '1:1' print really is 1:1 unless you measure it). Printed them off on A4 and hid myself in the garage.  I have uploaded 'Issue 2' of the drawing.

I chuckled as I set to work. The ruler still has splashes of blue overspray from when I built the first model about 15 years ago. The only problem is that the millimetres have got an awful lot smaller. I will need to print the front two frames and trace them onto the ply. Then I need to find the bits for the Dremel (I'm sure I have a trammel attachment for it). Before I start cutting I need to re-set my head. My 'spring project' was a table - started out as a piece of mahogany, 10" x 2" x 5ft long. Gotta think delicate, gently does it!

Ramon, I'll keep you posted  :-))

We have progress!


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Re: Donald Campbell's Bluebird K7
« Reply #119 on: July 05, 2015, 07:30:12 PM »

Hi ya Tim

Watching with great interest :-) what ply are you using here?   Already downloaded and going to talk to the Mrs to see if she can print the images off at work.

aye
john
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #120 on: July 05, 2015, 10:26:20 PM »

That's 2mm lite ply. More common for aircraft but weight is critical on this model.
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Re: Donald Campbell's Bluebird K7
« Reply #121 on: July 06, 2015, 07:58:00 AM »

Sweet build watching with interest  :-))
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #122 on: July 06, 2015, 07:46:43 PM »

Does this put it in perspective  {-)
(Sorry about the knees)
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Re: Donald Campbell's Bluebird K7
« Reply #123 on: July 11, 2015, 07:17:44 PM »

First Cut.
I found the trammel attachment and, to my delight, in amongst the kit of a million and one useful things to attach to your Dremel, a parallel routing fence that goes with it. I started by cutting the slots in the frames where the joint will be. The actual position isn't critical but they all need to line up. A parallel fence needs something to bear on both sides of the cutter so I cut the slots while I still had a sheet. (The very observant will notice that the frames are not the ones I showed last time. Although the position of those slots isn't critical I cut the slots and then realised I was about 7mm out from where they should be. I'd relied on memory instead of checking the drawing. :embarrassed:  I wasn't sure if I would be creating problems later so I just joined up the slots and re-drew the frames. By now, I have 1:1 prints so it didn't take long)

I then used the trammel to cut the frames out. They are circular so it was a doddle. You'll notice I decided to sacrifice a square of ply as a disposable cutting board. The new router bits are great but they're also six pounds a pop so I don't want to ruin them hacking into chipboard. The red spot on the trammel is, by the way, A neg. That point is really sharp! I have a couple more frames to cut that are not circular (different router attachment).

I've decided to change the design slightly. You may recall that I was going to keep the frames as sheets during the build then remove most of them later. I realised that this would entail a lot of difficult keyhole surgery and I've opted to add lightening holes now (cut with hole saws). Much easier and leaves the frames stronger - now I have the wood, I have a better feel for the strength. Is it worth it? I weighed the disks that I removed. 10 grams total. OK, sounds like nothing but the frames themselves weigh 80 grams so it's over 10% weight saving.

Oh yes, I weighed three sheets of ply while I have them intact. They weighed about 975 grams. From that I calculate that the density of (my) lite ply is about 445 kg/m3. That's a note for me as much as anything - I'll check what number I used in the CAD model later.

Hopefully, more progress tomorrow.
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Tim_M

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Re: Donald Campbell's Bluebird K7
« Reply #124 on: July 12, 2015, 02:10:28 PM »

On we go...........
I was thinking about all the details I had to cut in those frames today and, to be honest, not relishing the thought. It would be so much easier if I had a table router.
Aha! Half an hour later I have a table router! And I didn't destroy anything to make it (unusual for me). I have one of those conical router attachments for the Dremel. I just routed out a rebate in a piece of MDF so the cutter pokes through the right amount, fixed the router attachment with some wooden blocks and Bob's your uncle. Works really well. Go on you need one!

All the little notches and slots cut. Time to tackle frames A and B, the ones I had to trace because they're not circular. Where did I put them? You remember that piece of ply I sacrificed as a cutting board? Guess what was on the other side.  :embarrassed: Never mind. A quick re-draw and we're off. By now, I have also found the spring bow I bought as an apprentice. Beautiful instrument; 45 years old and as good as new. Brought back memories of getting a right royal rollicking from the (pipe smoking) drawing office manager for turning up to work without a tie.  {-)

Notice how I cut one of the frames on the table router. Actually easier than using the trammel.

By the way; my garage isn't really as messy as it looks in the photo's! And yes, that one of those Chinese sailing boats in the background. Whatever the experts say, for a total amateur it's a nicely made boat and great fun to sail, if ever I find the time.

Quick rub down to make the frames look respectable and on to the next stage.
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