Delage 15-S-8 Grand Prix (1/8)

[Roy vd M.]

Thanks @Pouln and @Schwarz-Brot for your elaborate reactions and advice. 

 

On 3/22/2017 at 8:46 AM, Pouln said:

But, you found out that measuring from one point does help solve it. That's why construction drawings always measure from one single point.

 

Ok I did not know that. Learning along the way

 

On 3/22/2017 at 8:46 AM, Pouln said:

The apron is actually the vertical part (the face) of the support.

 

In this instance I meant the cross-slide while I was trying to translate 'support', so I was wrong anyway; the part I had in my head was the carriage... I thought the English term for that was 'apron'. I have corrected my previous post correspondingly, thanks. 

 

On 3/22/2017 at 8:46 AM, Pouln said:

From the pictures I gather that you have a quick exchange toolholder. You just don't know that you have it.

 

Proxxon calls it 'quick exchange', I reckoned they were a bit overly enthusiastic in their terminology; I had seen a few quick-release systems in Youtube-vids. But if you say and if Proxxon says it's a quick exchange toolholder then it most probably is. I don't know what a non-quick-exchange-system would look like. 

 

On 3/22/2017 at 8:46 AM, Pouln said:

You can buy some more of the actual cutting toolholders and then you will not have to set proper tool height anymore.

 

True, and a good idea at that. 

 

On 3/22/2017 at 9:25 AM, Schwarz-Brot said:

Roy, is the positioning done via a ballscrew spindle?

 

It's simply a tapped hole:

 

 

 

On 3/22/2017 at 9:25 AM, Schwarz-Brot said:

But look into your machines specifications. Should be listed there how much (little) is guaranteed.

 

Unfortunately there's no info about that in the manual. 

 

On 3/22/2017 at 9:25 AM, Schwarz-Brot said:

I would suggest cutting the hex surface immediately after the lathe work without taking the piece out of the chuck.

 

That was my original plan and way, which I amended to get a better comparison, but thinking about it I must admit you're right. I'll prepare each spark plug in one go. 

 

On 3/22/2017 at 9:25 AM, Schwarz-Brot said:

Another thing: If you don't already know how - you should get used to standard ways of indicating measurements in drawings. There's a reason engineers do so. I am sure you can work your system out, but for anyone else it is pretty hard. I then would work from those drawings instead of the written step plans (or combine the two). - Engineering drawings usually make it pretty obvious what needs to be done to achieve the result your after. Since you already have the drawings it is not a big deal - just print the area of interest and write down the measurements by hand. Having a drawing makes it much more easy to imagine the next steps while working on the parts.

 

Although It's not in principal my intention to change my own drawings / work methods for the purpose of easier comprehension by anyone but myself, and although if anyone wants to also build a 1/12th scale Delage and wants to follow my suggestions he'll probably find out what I mean in my step plan, I do agree with you that it might be easier not only for others but also for myself to use standardized plans. I'll remind myself of your advice and will look into that as soon as I will have mastered all other challenges in this build. Too many things to learn, too little time... 

 

On 3/22/2017 at 9:25 AM, Schwarz-Brot said:

 

An alternative to getting several identical parts would obviously be casting. 

 

Frankly I'm enjoying this lathe work too much  

[Roy vd M.]

83. As mentioned before I intend to build a lightly pimped 'what if'-version of the Delage. At the moment I'm busy turning the spark plugs, which now finally seems to work out. Between the turning sessions I started sketching how I see the design of the car to be modeled:

 

- Car lowered;

- Lower tyre walls;

- Fourteen spoke sports rims; I have considered using the original wire wheels but in the end those do not seem to fit in visually;

- Modest tribal at the sides;

- Racing numbers removed;

- Small spoiler.

 

I did not want to overdo. Hopefully this design looks nice to your eyes, I'm curious to learn your opinions. 

 

An update on the spark plugs to follow shortly.

Original:




Planned:

[silver911]

Hmmmmm.....and the date today is.........

 

Ron

[Schwarz-Brot]

On 25.3.2017 at 8:26 PM, Roy vd M. said:

Frankly I'm enjoying this lathe work too much

 

There's some deep satisfaction to be found in that work. I understand exactly what you mean. So mesmerizing to see the spinning part adapting to the form given to it by the tool. And the satisfaction of productive work just gets on top of that.

 

I loved to work with lathes as well. And there's so much you can get out of them. There's a good reason a lathe is pretty high up on my list of tools to acquire.

 

For your subtle tuning - take a look into stancing. This might really add to the car!

 

Spoiler

NOT FOOLIN ME!!!

 

[PROPELLER]

Hum, my opinion, I'm sorry, a sacrilege, a crime maybe?

[CrazyCrank]

"Poisson d'Avril" as we say in, french.

@Roy vd M.You might replace the steering wheel by a bike handlebar

[Roy vd M.]

@silver911, @Schwarz-Brot, @PROPELLER, @CrazyCrank

 

I guess I'll just have a go at the original version, leaving the tribals and spoiler alone

 

(You're not too greedy an audience I must say... on another forum, where I thought I was know as a 'love everything original' kind of guy, they are giving me all kinds of advice to further pimp this hotrod...  ).

 

@Schwarz-Brot no joke is the fact that tonight for the first time I actually (and painstakingly) got a 2,4 x 4,5mm. spark plug out of the lathe / mill to a standard that could be final(ly usable). Only one flaw... to correct that I'd have to make another specific cutting tool.  On the other hand, the flaw is only visible if really focusing, for example through a magnifying glass. I guess it depends on how much autism will prove to be inside me. 

 

 

 

 

[NickD]

Hi Roy,

 

Having got one perfect sparkplug, you could always cheat and cast as many as you like in resin.

 

And on the subject of improvements, could you not stretch it a bit more and make the wheels even bigger. I'm sure Mr Delage would approve.

All the best

 

Nick

[PROPELLER]

I'm hit, not sunk... good shoot Roy!

[harveyb258]

Beautiful job on the spark-plug, Roy...hat's off, Sir!

 

On the subject of "pimping" this classic.....it's your model to create as you wish, however, I too think it would be sacrilage to alter such beauty. Just look at the sleek look of the black restored car....that's as pimped as it needs!

 

Keep up the good work matey.

 

Cheers, H

[Roy vd M.]

@NickD Resin-casting the spark plugs will not give the same level of results as turning them. Beside that I very much like the turning operations, especially now that I overcome several problems. 

 

I'll try getting the wheels a tad bigger

 

@PROPELLER Especially people who have seen several build reports of me spread over years, always defending originality in models, should probably have known better (on another forum that is). Your reaction was understandable and honest and I agree with it.

 

@harveyb258 I agree to what you're saying. 

 

Regarding the spark plug: it wasn't over yet...

 

 

84. Planning the replication of a spark plug turns out to be, honestly, quite difficult. Several problems to solve... and by solving the one you'll get to the next. To me the spark plug will have to be near perfect (to my own eyes) and until that will have been achieved I see all things I do as a learning process that will help me when I'll be doing less complex parts. From what I've seen of the car I estimate that the turning work on these spark plugs will be some of the most difficult throughout this build.

 

Coming close... 



The part is about as large as a grain of rice. On the photo you see a 8x enlargement. 

 

 

85. ... and then, all of a sudden, the idea comes to life to do things in a completely different way. To the workshop, trying and... it works! 

 

The spark plugs will be made in two parts, the one sliding into the other. The one part ('male') will have a pin turned at 0,95mm. The other part, having a minimal diameter of 1,60mm., will be drilled a 1mm. hole. 



86. Joined (don't mind the roughness of cut). 



Several opportunities and advantages:

 

- No more situations of having worked for 3 hours on one spark plug and, in the last half hour, making one single mistake. 

- Only one side has to be masked when painting the isolator.

- Steel colored parts can be either turned out of steel or treated by Blacken-It or the like. No masking required. The border between steel and porcelain colours is exactly right. 

- Preventing problems in positioning the small hex. This used to be one of the most difficult parts of the workflow. 

- It also enables me to use the 2mm.-milling bit rather than the 1mm.-bit that snapped off (honestly) at the start of hex #12 out of 12.... I was in shock

- The hexes can be processed after one another, leading to greater accuracy. 

- The hexes may be made by using a wiggler, possibly leading to greater accuracy. 

- The odds that the part is broken are minimized. 

- The table will not have to be reset every half hour.... including checking and setting. It costs time and energy... and it has to happen each time I change between lathe and milling machine... that's a real disadvantage of the two-in-one system.

- And more. 

 

Micro-level breakthrough  

87. So I made the first piece and it snapped off at 1,04mm., the weakest link being the taper. The idiot in me is finally going to give up and try to make the illusion of the (extremely small) tapered end by cutting an additional groove. Even under a magnifying glass the difference will eventually be barely noticeable. 

 

The test would have been a success if not for the end... there the piece snapped off at a diameter of 1,07mm... although it should have reached 0,95mm. Careful as I was. The follower rest was of no use, because it would damage the workpiece. I hope that I'll get to 0,95mm. on the next piece, by not making the tapered end. The visible part of the workpiece will remain a bit stronger. 



By the way, hasn't anyone become sick and tired of reading about these darn spark plugs all the time?  

 

Anyway, after several failed attempts whereby the rod was bent or cut off for unclear reasons, finally it worked out okay. The clue is to use cooling (cutting) liquid. Just a little bit, as I did before. The finish of the part is smoother and because the part will stay cold it will not be annealed. I can understand the advice to not use cooling liquid for larger diameter parts, but here it is not applicable. The maximum diameter of this top half of the spark plug is 1,3mm. 

 

After using cooling liquid, no more snapping off. 

 

It's a challenge to make a part of this, but to me this is the first good specimen. 

 

 

89. A few weeks back in time: I elaborately research what measurements the (non-surviving) original spark plug would have had. The 1927 drawing was restored (alignment / proportions / measurements).

Other sources showed that the drawing was shrunk in height. Unfortunately those other drawings can't be used to make the part. One of the drawings (from 1927!) even proved to be incorrect, probably an older version of the engine.  



90. I encountered several problems, for example because the workpiece was too thin / long. To stabilize it I intended to put it between two centers. First, drilling a hole...



91. Positioning the center... no problem... or...!?



92. ... the cutting tool can't reach the workpiece anymore. Repositioning the cutting tool toward the workpiece would lead to instability. This is therefore no solution for this small workpiece.



93. Meanwhile I learned to work with reducing clearance in the cross slide and, as can be seen here, the top slide.

The clearance can be reduced and set at the desired rate by turning a few nuts and a bolt.  



94. At one point in time the fifth or so step plan seemed to work... be it that here I made an error, making the workpiece look completely wrong.



95. It was quite an effort to 'recover' the table, after using the milling machine or after rotating the table at 79 degrees for the taper, to get it at exactly 0 degrees.

What I have gotten used to do is extend the top slide all the way and then to check (by eye) whether the top slide runs parallel to the bed along all of its length. If necessary a hammer is used to very lightly hit the top slide. The problem of not doing it as accurately as possible is that a (minimal) taper is applied while turning. After each change between lathe and milling machine this will have to be checked through turning and measuring the workpiece at several distances. Those who want to prevent this should buy a separate milling machine. If your workshop is large enough, be sure to do so. 



96. The end result is getting closer... 



97. But then of course there are the new problems. For example, how to perfectly align the hexes. To find the middle I tried to use a so-called wiggler, but that didn't seem to work here.

A wiggler is used to find the absolute center of the part to be milled. The wiggler turns in circles but is ball-coupled to the milling machine. By pushing a pencil (for example) downward along the wiggler needle, the circles will get smaller and smaller; in the end it will be dead centered. The needle will then point to the center..



98. The result is 'okay' but not perfect. The problem isn't merely to establish the center, but also exactly the right height. This has to be done by eye but this part really is too small for that. Going too far will destroy all work. Not going far enough, a 'plateau' is generated. Two or three hundreds of a millimeter makes all the difference. 



99. What isn't as accurate as I'd like it to be is the use of the self-made 'taper' cutting tool. The taper was cut alright, but the problem is that I have difficulty to assess how for I'll have to push it into the workpiece.



100. The following photo shows what part wil receive a taper. It's only the triangular hole and the light-colored metal below that. The rest of what you see is the (broader) underside of the cutting tool. An optical illusion... 



101. This seemed to give a good result, but the rings near the porcelain were added later (I got a bit more self confidence; and the drawing proved the grooves were taller) and I seemed to not be able to get them straight (disadvantage of repositioning a work piece into a collet and working it anew). The larger grooves were eventually to become part of the final step plan. 



102. The next problem: 'no twins'. By positioning the cutting tool slightly the end result will look radically different.



103. Then came the idea I already mentioned: dividing the spark plug into two parts.



104. After making yet another version of the step plan, I now tried to work with the follower rest. It could normally be used to support the workpiece at the cutting tool-opposing side. However... there was too little space for the follower rest; if used it would damage the workpiece.  



105. I'll fast forward a bit, skipping some pictures, or it would get very boring. Long story short: using cooling (cutting) liquid ensured that parts would not randomly snap off and that a smooth end result would be achieved. The cutting tool was straightened perfectly (left side) to make sure cutting was done fluently.

 

Here a bunch of failures, due to a non-perfectly-straight cutting and non-use of cutting (cooling) liquid...  



106. The cutting tool is positioned straight:



107. Finally there's a result that fully agrees with my ambition. Bonus: no 'follow up' of the cutting tool (to remove annealed / sticked-to-brass other brass pieces) was required, due to the use of cooling liquid. That stuff makes using the lathe on small parts like these so much easier. It also saves time. This is version 11 of the step plan... the final version as regards the top part of the spark plug. 



108. Only one cutting tool is used. Setting the cross slide is used only once (for eight parts), saving a lot of time. Turning the second specimen takes only 19 minutes. 

 

When (anxiously) comparing both specimens it appears that they look similar... although this was (finally) expected) I was extremely happy nonetheless. I started working on the third part right away. See here the result... I'm happy! 

110. Images say more than words. I made a video that shows all of the turning steps. Its length is a bit over 7 minutes. I have written a small commentary for each step.

[video=youtube_share;hhyMMEwDhbA]https://youtu.be/hhyMMEwDhbA[/video]

 

111. Going swiftly now... the eight top halves of the spark plugs are ready.

 

112. For completeness' sake, the final step plan as can be seen effectuated in step 110. If translation is required just let me know.

 

Total build time: 30h.

Total measurements study: 27h.

[silver911]

Forgive my asking....probably a stupid question but.....could you not have turned either in pairs or 4 at a time from a single piece of rod....along it's length?

A big advantage here is not having to realign/measure and seat so many pieces.

I recently did this (on the milling machine) when making electrical connectors for my Ducati build....all you need to remember is to leave some waste between each for separating.

This would also have the advantage that you wouldn't be so confined/restricted for working space around the cutting tools etc.

I was shown this way of working (it's called "step and repeat") by a friend who has been an engineer all his life.

 

Regards

 

Ron

[Roy vd M.]

@silver911 Thanks for the input; several reasons why that wouldn't work here, the most important being that the top of the spark plug has a diameter of only 0,38mm. That's 0,015 inches. Beside that ultra-thin diameter there are also some other smaller diameters. Even the mere turning on of the lathe would make the first part fly into space. 

 

The lower half of the spark plug: different story, same result. 

 

That having said I can certainly imagine situations in which your solution would work and save time. 

[silver911]

4 minutes ago, Roy vd M. said:

@silver911 Thanks for the input; several reasons why that wouldn't work here, the most important being that the top of the spark plug has a diameter of only 0,38mm. That's 0,015 inches. Beside that ultra-thin diameter there are also some other smaller diameters. Even the mere turning on of the lathe would make the first part fly into space. 

 

The lower half of the spark plug: different story, same result. 

 

That having said I can certainly imagine situations in which your solution would work and save time. 

 

Agreed...that's too fine a size to hold between each.

 

Ron

[CrazyCrank]

@Roy vd M.

 

Really strongly inspiring job and report of mistakes and methods, which, finally, provide a stunning result

 

Had you thought you could try to start turning a hex brass rod of the needed diameter, to avoid having to mill the hex faces on such a tiny part ?

 

[Roy vd M.]

@CrazyCrank Thanks for the motivational words. Yes I had received that advice before on another forum, but there are (were) six reasons why I didn't want to go there:

 

1) Two hexes have to be milled in each spark plug, each a different size. So one would have to be milled anyway. 

2) I could never find exactly the right diameter (exactly 2,10mm.). Or it would be a coincidence. 

3) I might get in trouble turning the sub-largest diameter on the lathe... traces of the hex could remain. 

4) My first idea was to first use lathe, then milling machine (this argument has ceased to be, by the way... more on that later). 

5) I want to practice using the milling machine as much as possible for the later spoking works.

6) Most importantly for me personally, it is my intention to build this model from the rawest of materials: rod, sheet, solder, wood, paint. In brief: this has been a dream of mine. And it would make me so much more proud than if I used aftermarket stuff for example. This is also the reason why I don't use aftermarket bolts. I'll make them all 'by hand'. 

[Robin Lous]

Not making at least one spare?....brave man! Never heard of the carpet monster? 

[Roy vd M.]

@Robin Lous Actually I did make a spare. Then I found out, when comparing them, that one of the 9 parts had an error so I had to throw it away. I decided against making another one... if it will turn out to be necessary I can turn another one. But you're right... the carpet monster is always jumping around in my workshop. Not that we have (a) carpet anywhere in our home, but still. 

 

Let's say I like to live life on the edge

[Roy vd M.]

113. I have some question about the spark plugs.

 

In the drawing as seen hereunder, two hexagonals can be seen. In the drawing they are exactly at the same position, rotation-wise: 

 

 

 

But I have seen photos of spark plugs online that show the one hex in a different 'rotational position' than the other hex. For example, these spark plugs all have a different 'relative hex setting': 

 

 

 

My two question: 

 

1) In these vintage spark plugs, what was the small hexagon used for? I would guess to set the electrode, but I'm not sure.

2) What would be a logical way of representing them on the Delage?

 

- All (approximately) the same relative position?

- Or exactly as shown on the drawing?

- Or would it be more logical that they would each have their own relative position? 

- Would it depend on whether I represented the car in the first race (all spark plugs were newer) or a later one? 

 

Looking forward to your thoughts. 

[Schwarz-Brot]

I can imagine two reasons for two hexes:

 

1. As you mentioned: To set the size of the spark gap.

or

2. The larger piece is an adapter that fits a one-size spark plug to some typical larger threads one might have found on engines of that time.

 

In either case the position of the hexes would be random. Technical drawings are not to picture reality but to transport information about measurements and / or functionality. This means sizes, shapes and positions can be different from what you'd see in the real world. Shocks for example would be shown in either their lowest / most compressed position or, more likely in a technical drawing - in completely relaxed state at the other end.

 

I am glad you found a way to duplicate your pieces. I think retrying the cooling liquid was a major helper here and it show that you get a feeling of the process. A real machinist feels, smells, hears and sees what his parts and tools need

I feel a bit embarrassed I advised against the use of cooling liquid. This is missing experience with such small parts. Sorry for that.

Really interesting to see how differently things behave on a small scale.

Edited April 8, 2017 by Schwarz-Brot

[Mark_1984]

The smaller hex would be a hex head on an external threaded pipe (Sorry, I don't know the proper name for it) the would hold the insulator in place.  I.e.  The spark plug would be an assembled component as they didn't have the manufacturing technology to make them in one piece as they do today.

They would just be at a random relation to the larger hex.

 

Your attention to detail on the plugs is impressive.  I'm looking forward to your start on the engine block.  How are you going to tackle that ?

[Pouln]

Well Roy, I'm in awe with your stamina. In the end, you've nailed it and at the same time found a solution that made fabrication so much easier (using 2 parts).

I agree with the remark that the drawing of the hexes will not be representing the position of the hexes on the real thing.

in real life they will mostly not be positioned the in line.

 

[Roy vd M.]

@Schwarz-Brot Thanks for your suggestions. I guess Mark_1984 has the final answer here, it makes perfect sense. 

 

Re. the cooling liquid: I understand why you advised against it and it was a well meant advice. I'm happy with all the hints, tips, advice received and if 5% of yours doesn't work the other 95% would easily make up for it. Beside, it teaches me more than doing everything perfectly for the first time. I guess this topic shows, superfluously, that I make mistakes all the time. That costing a lot of time, is compensated by the things I now learn, preventing the mistakes at times where they are more crucial. 

 

1 hour ago, Mark_1984 said:

The smaller hex would be a hex head on an external threaded pipe (Sorry, I don't know the proper name for it) the would hold the insulator in place.  I.e.  The spark plug would be an assembled component as they didn't have the manufacturing technology to make them in one piece as they do today.

They would just be at a random relation to the larger hex.

 

Thanks, that seems like a solid explanation! I'll make them random. 

 

1 hour ago, Mark_1984 said:

Your attention to detail on the plugs is impressive.

 

Thanks. It brings me great joy (as long as it works :D)

 

1 hour ago, Mark_1984 said:

 I'm looking forward to your start on the engine block.  How are you going to tackle that ?

 

Right, there's a bit of a disappointment probably. Before I'll do the engine I'll first await the exact measurements from Revs Institute. Whereas the car was planned to get back to Florida a few weeks back, I was informed last week that it won't be back until later this year, possibly even September. That's because of the 90 years-jubilee of these cars.... Brooklands museum has the car on display right now. So I'll have to wait for that... meanwhile I'll have to find something else to do. 

 

How I plan to tackle the engine: I reckon the hardest parts will be the cam covers. I'll start with those. On the first page of this thread you can see some thoughts on how to do them. My plan right now is to use brass sheet, shape it, drill holes to fit small pipes, silver solder the aluminium (I already have the specific solder for that job) and then spend the next bit of time applying all the 'turned metal' swirls. 

 

@Pouln Thanks for your support. You mention the term stamina... for me the end result is almost never the thing I look forward to, no exception with this Delage. I enjoy making each part as well as I reasonably can. Probably this clarifies why I've been having such a good time during the creation of these small spark plugs, and that it doesn't bother me at all if something at first doesn't work. No time pressure here  

 

I want to show you the first combination of hexes, made out of steel. I must say I'm in awe by the quality and precision of Proxxon's milling machine. It isn't the largest or the most expensive but it is (considerably) more accurate than I had imagined it to be. I can see no flaw... very impressive, compliments to Proxxon here (not always in order, but here they sure are): 

 

 

[PROPELLER]

Congratulations Roy! Your perseverance and details research are rally amazing! I love that. For machining tips and tricks, take a look at the kind of this site...

 It was very useful for me!

http://www.homemodelenginemachinist.com/forumdisplay.php?s=503b463bc79936fc4d08799bd3074002&f=31

Dan.

[larchiefeng]

Those are some pretty nice examples of spark plugs Roy. I admire your wanting to make everything from scratch including all the nuts and bolts; that's going to require a lot of patience and perseverance! Lots of good info here on lathe work, thanks guys.