** ON TO THE NEXT BIT ** Nose to Tail - 1972 Spitfire MkIV restoration upgrades!!

[Dick Twitchen]

13 minutes ago, Colin Lindsay said:

"I never knew it did that!" when someone shows me..

Usually a teenager!

[Badwolf]

Tony/Doug - Chargers - They will be on again soon I'm sure. If we all keep an eye out in both stores one of us can post it up.

Colin -  My life is adventurous enough as it is at the moment. Having more than enough adventure trying to fathom out the workings of the new unit. Sorted most things except..bluetooth setting, usb/sd card playback, various presets like 'dx'  'loc' and aux. Getting there though. Maybe I'll re-write the instructions for others. This unit is smaller than other versions of the same type. Only about 3 inches deep, built in blade fuse brilliant for the price (at the moment)  I can see why Paul likes it. Colin, you will love it. Only ordered over the B/H weekend, arrived this morning.

[Colin Lindsay]

29 minutes ago, Badwolf said:

I can see why Paul likes it. Colin, you will love it. Only ordered over the B/H weekend, arrived this morning.

I don't need one... but on your trusted recommendation, I might just dip a toe in. That's this week's pocket money gone.

[Badwolf]

That's it. I have finally passed through some sort of time/age barrier. I am sitting in a 1972 Triumph Spitfire listened to music on the 'retro' style radio, 'Groovin' With Mr. Bloe' stored on a 21st century SD card, testing the suspension of a car in which it is very hard to groove in.  Help me please... anyone!!!  Very very pleased with the noise which is now showing up the fact that the front speakers are held in place by the speaker magnets on the body shell.  Hi-fi hell but what the.....  Its loud, its brash, it reminds me of the youth that I missed.

Colin - This is the one I got... https://www.ebay.co.uk/itm/Car-Bluetooth-MP3-Player-Retro-Radio-Stereo-MP3-USB-SD-FM-AUX-iPhone-Handsfree/223620945119?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[dougbgt6]

I have AC/DC on a memory stick in my disco radio  "Highway to Hell" has a whole new meaning bouncing down the A4 in the GT6.

db

[Colin Lindsay]

ACDC on USB on the A4 in a GT6? Cool!

Looks like I'll have to stick to the one I have for now... posts to UK and Europe but NOT to Northern Ireland? Anyone know where we are now? I'm lost.

[Badwolf]

Sorry Colin. Looks like the list of excluded countries is a fleabay standard list. It might be worth messaging my seller to see if they will ship to you. I suspect that some of them don't even realise where N.I. is and that they are losing trade because of the exclusion. Pity we didn't realise before your road trip last week. You could have picked one up.

[Colin Lindsay]

2 hours ago, Badwolf said:

 Pity we didn't realise before your road trip last week. You could have picked one up.

Pity I hadn't known I was so close! I'd certainly have called.

Found one seller pricing them at £13.97 who was happy to post to all of Uk, and was even happier to accept an offer of £11. I'm too easily talked into things.

Next local meet will be a lecture on how to set them up... starring me with a 12v battery, lots of leads, and a manual translation.

 

[Badwolf]

Well done, cheaper than mine.  Is yours the longer version or the short one.  Would you like me to make a list of what I have sorted out up to now, to start you off?

[Colin Lindsay]

2 hours ago, Badwolf said:

Well done, cheaper than mine.  Is yours the longer version or the short one.  Would you like me to make a list of what I have sorted out up to now, to start you off?

77mm deep. I never looked, to be honest - just ordered by the main photo alone. I think a stickie on how to work these would be in the interest of a lot of others!

[Badwolf]

Mine is 65mm deep. There does appear to be several versions. My instructions refer to a red and a yellow fuse but there is only a red one that I can find but it is a useful addition. SD card slot works, power from the usb but no noise yet and intesting stuff on the set-up that I have not worked out yet. I will have another play with it on Sunday and draw up some basic set-up instructions which can be updated as we go along. Bluetooth signal picked up by my phone.. amazing, does it work... absolutely no idea. This unit is good fun though (I really need to get out more).

[Paul H]

1 hour ago, Badwolf said:

Mine is 65mm deep. There does appear to be several versions. My instructions refer to a red and a yellow fuse but there is only a red one that I can find but it is a useful addition. SD card slot works, power from the usb but no noise yet and intesting stuff on the set-up that I have not worked out yet. I will have another play with it on Sunday and draw up some basic set-up instructions which can be updated as we go along. Bluetooth signal picked up by my phone.. amazing, does it work... absolutely no idea. This unit is good fun though (I really need to get out more).

Blue Tooth does work . I use Spotify on my iPhone 

Paul 

[Badwolf]

Colin - On Jonathan's radio thread you asked me to let you know how I got on in returning the original fleabay radio. Well, I complained about: no release pins supplied, no decent programming instructions and incorrect details in the listing (sd card, am, dab, bt etc). They came back offering a 30% discount and the suggestion that I took it to my local store for them to repair. I said no. They then offered a 50% discount. Again I said no. This morning I put it in fleabays hands and received a full refund within 2 hours. So I still have the radio, a full refund and no (decent) address to return it. That is the story so far.

As for the adhesive tests, I have been a bit busy stripping the underside of the bonnet of all the sh*t that has been painted on it over the years, along with other more pressing matters, but I will post the results, probably next week. Things are 'interesting'

 

[dougbgt6]

BW,

What did you use on the bonnet? I have stage one sound deadening, underseal. Who did that?!! 

Oh,  It seemed like a good idea at the time, I was young and impulsive. 

Doug

[Badwolf]

I have no idea what it was. Could have been some sort of underseal over the paint. Nightmare to get off even with Starchem Synstrip. Its taken nearly 5 litres to get back the bare(ish) metal. The coating appeared to be very brittle even after treating. I think it was put on during the original restoration but I'm not impressed with it. About a cm thick in places.

[dougbgt6]

Yewh! My underseal has been sprayed by the timing chain/crank cover oil seal leak, I think it will peal off easily, but I don't want to touch it.

db

[Badwolf]

After three days of paint stripping I have finally got rid of 99% of the old paint and underseal. The remaining bits are either difficult to get at (wheel arch tops) or not shifting for some reason Now ready for rubbing over and painting. Seens strange to breath without a face mask for the moment.

[Bfg]

On 21/08/2019 at 13:59, Badwolf said:

I am trying to evaluate all ideas so the more the merrier. Criticism, ideas, 'wouldn't do it that way', it all counts to helping me and so everyone on the forum. The comments already made to me both by an expert in speciality steel and about the length of time that bonding has been used has absolutely staggered me. If what I am trying helps anyone other than me, I will be well pleased.

For what it's worth, I owned a fibreglassing business at one time designing and making my own products including kit-cars, and then I worked in yacht design for many years.  Fibreglass (GRP / FRP) is of course simply bonding one fibre to another. A few years back I had a confrontation with my Naval Architect bosses because the company (Oyster Yachts) were moving from laminated (effectively built-in) bulkheads and structures to having a hull shell with a webbed frame structure bonded into that.  I argued that although this might be 'OK' for coastal day sailing boats - it was a dangerous practice for a company which specialised in quality offshore sailing boats, whose owners might expect their vessel to hold together even when rolled mid-ocean in the most adverse conditions.

The issues I explained ..as a staff design-engineer, but not a structural engineer,  was that the inside of the hull and the underside of the moulding would have to be so very clean and also scuffed for key - for the adhesive to bond properly.  Test bonds and their resultant performance were very different to a production environment.  Oyster Yachts were never a large scale manufacturer and so their boat building was akin to cottage industry practices, who subcontracted out their fibreglass production. Quality control would be a significant problem. 

Then, the adhesive compound would have to be applied to the underside of the flanges of the inner mouldings (which incorporated structural elements like essential stiffening frames and ribs, as well as the footings for structural bulkheads).  And this big floppy (freshly made, so still green / not fully cured) moulding would have to be lowered into exact position within the hull.  Any slight wandering would swipe the adhesive from where it was meant to be.  And lowering the moulding vertically into the curved upwards sides of the hull would also wipe the adhesive from where it was originally applied. 

For exact positioning the moulding would finally have to be giggled into position, smearing even more adhesive from where it was 'designed' to have been applied.  Because the (unskilled) staff would have to oversee this from above, and the adhesive would be under the flanges - even if they cared to, they simply couldn't see if any place had been accidentally wiped of all adhesive - even in crucial places where loading / the bond was most critical. 

I went on to add that the tolerances necessary for the rough inside of one panel to sit against the rough side of another would have to unduly slack ..not least to allow it to be maneuvered into position when being fitted.  But because the 'rough insides' would not be absolutely even, the gap for the adhesive would be dimensionally unpredictable. The ideal amount / depth of adhesive might be 0.5 - 1mm.   On the 46 foot boat we were discussing at that time, the hull thickness might possibly vary by 8mm (perhaps quite locally)..due to these being hand laid-up, the laminate counts, the material overlaps, resin to glass content (how much it was rolled), and drain down.  As a result, and quite possibly in some places - the hand-applied bead of adhesive might not even touch both hull and inner moulding, and in others the fit would be so tight that all the adhesive would be squeezed out.  In either (albeit localised) situation the bond would at best be very weak. 

So, to compensate (build in a safety margin) there would have to be more flanges to bond to.  And the amount of adhesive (both in weight and cost) and the time it took would be counter-productive to the cost savings the process was supposed to introduce.  As I say, this may be a different scenario where mass production, trained staff, and/or costly quality assurances are in place. 

And then for the adhesive not to sit useless ..squeezed out and laying as a bead alongside the flange, it ought to be squeezed back into the joint - similar to what a brick layer does, or else be injected from the side - like when caulking a door frame. But mostly either of these options was impractical because of the flanges would shaped be like the rim of a top hat section, where only the outside of the rim was (sometimes) reachable.  Inbetween the top-hats (shaped to be a structural beam) was frequently to be left filled-in ..as a smooth and clean liner to the boat's interior ..so subsequent access to caulk under any of these would be impossible. 

I also pointed out that all adhesives have a working time, so once committed the task needed to be completed quickly and without break, even if things went tits up.  And if it did go wrong then all that adhesive would have be removed and cleaned back so as to start again ..a nasty and very time consuming job !   Worse still was if delayed too long - then the adhesive might start to set before the rest of the moulding was bedded down in position. It could be bedlam.!   Again very different to a production facility where that amount of adhesive might be quickly applied by experienced staff, so as to allow more time for positioning and clamping in place.   But in an old and dirty boat-shed ..that was darn hot in the summer and bloody freezing and damp in the winter - things might get a little tense.! 

Furthermore, on such a large scale ; the lb/sq inch fitting-force on those flanges would be 'considerable' ..and yet ought to be relatively even throughout the 40+ foot boat.  And because the area of all those flanges added together amounted to several square metres - to squeeze that adhesive to a predetermined depth would be quite massive.  So the inner moulding would need to be held and braced securely within a steel jig for its fitting into the hull (..which would still be in its mould), to prevent the inner moulding and its flanges bending out of shape.  That would further limit access for seeing what was happening, for checking, and/or for squeezing the adhesive back into the joint.

 

Naturally,  as a mere staff-employee,  my words of caution were ignored by those with higher status and ego.  And I was sidelined to work on boat systems.  It appears the practice  continued to other models in the range, because in 2015,  two and a half years after I was made redundant - the keel fell off a nearly-new Oyster 82 ..in calm weather sailing.  Its keel to inner pre-moulded structural-frames moulding joint failed and the vessel very quickly sank. Fortunately the crew got out and, as they were not in the middle of the Southern Ocean, were rescued.  Oyster, the company, however floundered and then sank.  A very sad state of affairs from what used to be the premier brand in British yachts.

- - - 

I'm not saying one way or the other whether you should do so, but there are many points (above) which you may wish to consider when bonding (non-structural until in an accident) parts of your car together, particularly how to ensure there is enough adhesive within your joints to work.  Also how you might handle awkward panels rather than small test pieces, so the gaps are even and not too tightly squeezed. And in particular how to apply / squeeze the adhesive into the gap and then smooth its edges.  

Smoothing all around the edges is crucial for a strong joint ..because while you may achieve a good bond between the adhesive and each piece of metal, a failure will almost always propagate from a tiny split or hard corner.  To better understand this, please consider plastic packaging ..some of which is disproportionately difficult to open. But if there's even a tiny slit or sharp corner of a serration, then once the tear has started it's almost impossible to stop it tearing all the way down. The ground coffee I buy from Aldi is so packaged ..and its tear is unpredictable, so I now only open that over a clean dinner bowl .   As it happens.. this conversation  is significant to your query about the strength versus a larger bonded surface area :  It's only as strong as the weakest split.    

Materials don't matter so much as you might think.  Forged or rolled iron and steel is particularly resilient to splitting - which is why it's such a successful structural material. As are some adhesives like butyl rubber,  but most all other materials from the hardest jade (jem-stone) to the floppiest raspberry jelly will split easily once cracked.  Some materials like timber, slate, and even woven cotton have a quite predictable direction (of failure) in its structure, whereas many others are far less obvious ..but still once a crack starts it often goes right through.  

In this respect it's very interesting that a drilled hole can stop a crack from propagating further.  The stresses no long work at a molecular level to unzip (split) the material but are led to flow around the hole (where there is no sharp corner or split).  A similar situation happens with spot welds, insomuch as if one splits then there is no direct link (crack) to the next. So although the forces might be sufficient to tear several or all spot welds apart - the force needed to tear one is much the same as the next each time (..although once some have come apart the leverage may increase). This is very unlike splitting which happens through a single material.    

So one of the primary keys to any built-up structure ..whether in fastening or bonding panels together or in designing the next Titanic  - is to avoid any place that might focus stresses and be the start of a split, whether that be a rounded bead which instigates what appears to be a failed bond between the adhesive and what is being bonded,  a split, a line of weakness, or simply too sharp an inside corner.   Of course yield points are also used to good advantage, for example a white-water canoe may be designed to break in half (at the cockpit) rather than trap its occupant when wrapped around a rock.

Your further investigations might also go on to encompass chemical, heat, and/or UV breakdown of the adhesive.  Often plastic materials go hard and in time go brittle or start to crumble when exposed to prolonged heat soak, certain chemicals, &/or UV ..which in turn leads to their cracking.  Other plastic materials seriously soften when exposed to such environments.  Decent rubberised products used in the automotive industry are good for six to ten years. Others are 'disappointing'.

I'll stop there for now, but possibly this offers something(s) to think about.

Bfg.  

 

[JohnD]

Fascinating, bfg!     I made several GRP components for Silverback, and learnt a lot in doing so (in an amateur way!).    In particular, joining previously made panels, I found as you say that ensuring they were clamped together while bonding was essential.  

I was especially impressed by the strength of double skinned parts with honeycomb filling     The estate roof I made was a quarter the weight and many, many times stiffer than the OE metal roof!   All thanks to paper honeycomb!

John

[Bfg]

Hi John

yes perhaps the single-most great disadvantage with bonded joints is holding them still, and in shape, while they individually fully cure.

And again yes..  cored composites are brilliant and imo not yet used nearly as much as they might be.  I replaced the (sodden) end-grain balsa core with foam core for the whole length of the bridgedeck on my aged (classic !) 30ft sailing catamaran. It was not difficult to work with ..but the many benefits over solid GRP laminates are tremendous.  I don't suppose you have a spare estate roof in grp ..going for a song,  do you ? 

Pete

[JohnD]

No, but I have the mould!  I might be induced to get it out and try again!

I also tried polyurethane foam as a spacer, but it's open cell and soaks up resin, making the finished part far heavier than needed.

John

[Bfg]

^ indeed PU foam is heavier both in its own right per sq.ft. for the same thickness and yes again it does use more resin to bond. However for what I needed (ie., strong enough for my 110kg to jump down onto)  it's also tougher.  I'd think honeycomb is lightest for a roof and if you have problems with adhesion then switch to epoxy resin.  Btw a paint finish is much thinner and therefore lighter than gelcoat, but if you do without then first apply a single layer of surfacing tissue before applying your laminate, otherwise you'll have a rash of surface pinholes to deal with. 

If you do have another try and find you're not happy with it - then I'll have one of your seconds.  I'll be chopping it up anyway for use on another car but it will give me a lightweight starting point to build upon.  

p.s. I understand from local members that estate tailgates are hard to come by.

 

Have to go now before the off-topic police arrive.

Pete

[Badwolf]

Bfg - Sorry about the slow response, been away. Thanks for your insight. What I am doing is purely experimental, but in view of the exceptionally poor welding which was done on the repair panels (came apart with the twist off a screwdriver/panels welded with no anti rust treatment on the inside), the adhesive that I am trying has got to be an improvement. Indeed half a dozen pop rivets would be preferable. Will post the results shortly for you and John to pick over. All thoughts are very gratefully received but in my situation, thankfully any failure will not result in sinking without trace!!

[Colin Lindsay]

On 29/08/2019 at 18:30, Badwolf said:

Colin - This is the one I got... https://www.ebay.co.uk/itm/Car-Bluetooth-MP3-Player-Retro-Radio-Stereo-MP3-USB-SD-FM-AUX-iPhone-Handsfree/223620945119?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Mine arrived yesterday; took about a week. First impressions are that because of the silver front moulding they're not as solid as the all-black version, but it's closer in looks to the old Motorola version that i'm replacing in the Herald. Is yours still behaving?

[Badwolf]

Colin- Not had a chance to experiment further as yet as I have been away.  Will post further updates about it later in the week. Hope to do instructions as well.