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Amen to that. Then you think you have finished a panel, only to look at it from a different angle ...

Pete
 

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Discussion Starter #582 (Edited)
The bumper story II

















It turned out that getting the bumper wing roughly in shape caused a line of buckles so deep inside the U-shape that they could not be reached with the existing tools. There are two options of how to remove them. The first but radical one is to cut the part along its welding seam, shape and planish with the English wheel, weld together and rework the weld. This I will keep as the last way. The other way is to make some tools to reach inside the U and planish the surface with a hammer, which IMO is more difficult than pulling a panel through the wheel.

However, a custom double anvil which I made out of stuff I had prepared in the past worked really well. The two halves of English wheel anvils are remainders of other anvils I made some time ago. The shaft is a leftover from my last manufacturing batch.













While figuring out how the part has to look in detail, it showed that the two references I have, differ in various points. The most obvious difference is the “flat edge” of approx. 1cm instead of the round edge on the other. The latter has a plain upper side which corresponds to the even underside of the rear fender. Both parts have different dimensions, mainly the opening of the U is different.

The Asian part generally follows the flat edge part, no wonder, because that was the part that served as a pattern. But the shape of the front end is not so good and the overall measures are way too big/wide.











One of the trim parts had a buckle, which probably had been created during dismantling. Trim parts are difficult to repair but I accepted the challenge, prepared a small aluminum anvil (a piece of aluminum rod actually), upgraded the surfaces of my lightest hammers, the bigger one of 100 g and the smaller one less than 50 g and tried to hammer the buckle out with very light beats. Achieved a considerable improvement but the task is not finished yet. Nevertheless the hammers leave some marks on the surface of the part which will have to be smoothed out later on.



-Timelapse -

Did some work on the part in the meantime. It shows that there is too much material at the elbow. As it is not possible to shrink the panel in this area, at least a partial cut will be necessary.















Have made new backplates for the long lateral trim pieces. While fitting them I found out that the left part does not end on the fender but on the rubber support pad of the tail light. This is how the car left the factory, but as some stainless-steel welding rod has to be ordered anyhow, I will try to correct that.
 

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ahh, the trims. they provide another challenge don't they. i have a similar situation with my appia vignale project. some are damaged, some are missing and i will need to manufacture them. it's interesting how much difference there is from one side of the car to the other. one of the side spears is almost 20mm shorter than the opposite side. is the whole car 20mm short on that side? hmmm.
like you, i will need to make some specific anvils to shape the trims, so continue to post your solutions please.
 

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[QUOTE = "1750GT, post: 8513310, membro: 4781"]
Ciao Giovanni .... il mio interesse è stato accentuato dal commento di Hubert in Post 580 ... dove possiamo vedere il blog che menziona?
[/CITAZIONE]
[QUOTE = "1750GT, post: 8513310, membro: 4781"]
Ciao Giovanni .... il mio interesse è stato accentuato dal commento di Hubert in Post 580 ... dove possiamo vedere il blog che menziona?
[/CITAZIONE]
è qui Non aspettarti cose meravigliose, è la mia prima esperienza di restauro ... Ho fatto delle scelte, soprattutto all'inizio che con il passare del tempo non l'avrei più fatto, avendo visto le cose e accumulato esperienza ... Purtroppo ho iniziato a scrivere dopo tanto tempo che ci stavo lavorando, quindi troverai le foto della situazione iniziale a pagina 12😩
Di recente mi sono registrato su Instagram e trovi le cose con un po 'più di ordine, ma meno dettagli ...
Bocchigiovanni85
#passioneflaminia
Buona visione
Giovanni
 

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Hubert, per quanto riguarda la testa dei martelli, per non graffiare e lasciare segni di colpi nella finitura, dovresti provare a usare martelli di gomma o nel caso in cui colla un tassello di gomma sulla testa. L'avevo trovato molto utile.
 

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Discussion Starter #587
Hubert, per quanto riguarda la testa dei martelli, per non graffiare e lasciare segni di colpi nella finitura, dovresti provare a usare martelli di gomma o nel caso in cui colla un tassello di gomma sulla testa. L'avevo trovato molto utile.
That is a good idea. I do have plastic and aluminum hammers of various sizes, but not that small. So covering/plating with some plastic material will definitely improve the surface of the small hammers.

In this particular situation my thinking was that a hard surface is required, while the back (the "anvil" made out of aluminum) is comparatively soft. If a soft hammer would be used, it would absorbe the uneveness of the work piece so that the buckles would stay. Hitting the raised areas with a hard surface while the backing is "soft" should lead to the intended shrink, at least that was the theoretical background as far as i understand it. Hard backside with hard hammer will remove the buckles as well but inherits the danger of stretching the material when hitting to hard, one has to be very careful when doing so.
 

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when i need a plastic cover for my body hammers i use a product called durasurf. made by crown plastics. i'm sure you must have an equivalent available there. it's thin uhmw-pe with very strong pressure sensitive adhesive. i use a thin section of it and replace it when it gets ruined. i use a sharp gasket hole punch closest size to the hammer face and ease the edge of the perimeter.
i also use it to cover my anvil in some instances, like working aluminum pieces or thin stainless sections.
 

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Discussion Starter #589
Liner protrusion





















Lancia specifies a protrusion of the liners of 0,04-0,06 mm. After fifty or more years the liners regularly fail to keep this value. Some show much bigger protrusion due to corrosion of the seat, most of them have sunk in. The protrusion is very important to get the right surface pressure on the head gasket, especially when running high compression ratios.

Started today with the assembly of the first of the 3.0L triplet I am preparing at the moment. Measured the odd liners 1-3-5. One was 0,16 mm out, the others 0,02 mm. After removal of the liner and cleaning of the seat of no 1, it had no protrusion any more, 0,00 mm.

There are different ways to gain back the required value. One could skim the surface of the block, which would keep the differences between the cylinders but create a protrusion again. Can not be done at home because special machinery needed.

The liners can be turned down on the lathe and a copper shim/gasket can be used to achieve the needed height again. Again, precise machinery is needed, the shims (e.g. 1mm) have to be made or sourced and each liner has to be worked individually as to get even protrusion values afterwards. The forty years old lathe in the company definitely is not the right machine for this job.

There must be an if not more elegant then at least easier way to lift the liner in the seat. When using a center-punch one creates a crater. The material displaced forms a rim around the crater. I used an automatic center punch to place three punches at about 120° from each other on the liner seating in the block. Inserted the liner, et voilà, the liner stands out by 0,06 mm.

Now I will fill the gap with a special sealant we use for high temperature applications of more than 300°C. This sealant is gap filling and hardens after a few minutes. I have used this stuff successfully on previous engine overhauls.



Will address the bumper issue next.
 

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Your method of raising the liner sounds interesting and if you have successfully used it in the past, good. However, I would make sure that the sealant can stand the compressive stress when the liner is installed and the head bolts torqued. If it's ductility and compressive yield are greater than aluminum it should work reliably. Otherwise the low surface area of the center punch dimples will allow yielding and you won't achieve the clamp load intended.

How does this affect future removal?

I have heard of the shimming method used to balance the deck height of Porsche air cooled engines - same idea. Not sure what the ID /OD of those would be, but sourcing the shims is probably not an issue regardless. Except for axial runout, the lathe cut does not need to be very precise.

To each their own, which makes this hobby interresting. I wish success to you.

Mark
 

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Discussion Starter #591
Your method of raising the liner sounds interesting and if you have successfully used it in the past, good. However, I would make sure that the sealant can stand the compressive stress when the liner is installed and the head bolts torqued. If it's ductility and compressive yield are greater than aluminum it should work reliably. Otherwise the low surface area of the center punch dimples will allow yielding and you won't achieve the clamp load intended.

How does this affect future removal?

I have heard of the shimming method used to balance the deck height of Porsche air cooled engines - same idea. Not sure what the ID /OD of those would be, but sourcing the shims is probably not an issue regardless. Except for axial runout, the lathe cut does not need to be very precise.

To each their own, which makes this hobby interresting. I wish success to you.

Mark
I am aware that it is an unconventional method and I will report whatever happens, success or failure. Yet I have spent quite some time thinking back and forth.
As you say, the center punches will hold almost nothing, they are really only ment to position the liner.

The sealant has nothing in common with the universal sealants we use to seal valve covers, oilpans and so on. These products, like Hylomar blue (do you know that in the US?) have a high elasticity once they dried.

The material I am using hardens completely. It gets so hard that you can break off excessive material. It is capable of filling bigger gaps and very rough surfaces. Once hardened the surface stickiness is zero. It does not glue to the block or the liner, therefore removal of the liners is no problem.

The first time I have used this material was 11 years ago and the engine is still running without issues.

Regardless, the whole project is a big experiment and although my intention is to build a durable Autobahn burner, I am prepared to face some setbacks. Hopefully the camera is on when they happen!
 

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Interesting that there is no adhesion to either side. That is good - allows recovery if the plan does not work as intended. I wish you luck, and your previous experiment makes a repeated attempt worthwhile. Sadly, we will need to wait quite a while (hopefully) to prove success. [much less to prove failure] :)
 

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Discussion Starter #593 (Edited)
This is # 13 with that sealant. Bad omen? Hopefully not, I was born the 13th. 🤔

Will keep you informed. Meanwhile I have made a support to improve measuring, measurement readings can be reproduced to 0,01 mm now.
 

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hubert, do you mind sharing the name of the product? there are instances when a product like that would be useful to me. not for piston liners mind you, more of an industrial setting.
 

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Discussion Starter #597 (Edited)
Mishap













All liners have been positioned in exactly the same position +0,06 mm. Made a board that can be bolted to the block for this (measuring) purpose.






Pistons/pins have been tared to the same weight with a difference of 0,0 g

Conrods tared to difference of 0,5 g for total weight and balanced on small ends to 0,0 g. The 0,5 g difference is the result of the last conrod being lightened a little bit too much, all others are 0,0 g difference. I could have added the 0,5 g, but was too lazy . . .

Crankshaft plugs have been removed and crankshaft has been cleaned and ground to 1st undersize.






When inserting the pistons one piston ring cracked. It slipped my attention that it was not covered by the adjustable sleeve at one end and got squeezed.


 

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Discussion Starter #598 (Edited)















The engine rack that had been bought some fifteen years ago has been annoying me since the day I unpacked it. To be fair, it worked primitively but ok for the money, but turning the engine was difficult, the support I had made was not ideal, because it blocked the sides of the engine and the wheels are a real mess.

Now, while #stayathome is everydays (or everyone´s) credo, upgrading the workshop equipment by DIY and intensifying project work appears to be the splendid future for the next weeks.

First thing: Build a better engine mount. Specifications are: tiltable to +-30°, best possible accessibility incl. flywheel, easy operation (ball bearings), use on the bench or anywhere else in the shop.

Still needs a little bit of finishing and paint, but it works fantastically.

Modified the old rack as well, so the new device can be mounted on it.

The engine "La Bomba #1", is prepared for final assembly, but as the Italian head gasket supplier is closed due to Corona, I have to wait. Italy is hit hard. Hope for my Italian friends that the epidemic will end there soon.
 

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"L'Italia è colpita duramente. Spero per i miei amici italiani che l'epidemia finisca presto lì".
Grazie.
Buona fortuna anche lì.
 

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hmm, parts of that stand look familiar to me. is that a 4x130 bolt pattern on the pivot assembly? nice little stand. i love building my own stuff too, you get what you want that way.
 
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