Author Topic: Bugatti Typ 50 1/4 Scale model  (Read 46017 times)

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #30 on: February 05, 2017, 07:59:57 AM »
Found some information in the megasquirt manual about ls1 chevy coils, wil give this also a try.
Orderd some caps.

Michael

Offline keith5700

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #31 on: February 05, 2017, 08:51:14 AM »
Michael, please bear in mind I'm not an expert on this, I just know what worked for me.
Roger is on the right track. I tried resistors but had no luck. I ended up with carbon resistive leads with just a short bit of 'scale size' ht wire at the engine end. At least 10kohm of wire. The plain wire needs to be as short as poss.

Then you need to sort out the earths. Everything needs earthing to the same point, either the battery or the block. The block worked better for me. Just run a thick cable from battery to block, and then earth everything else to the block.

I used screened cable for all the sensors, and earthed the screen to the Megasquirt case only, leave the other end free.

If you have no comms issues the that's great. I had to use a Bluetooth connection to get it to work.

Are you using Tunerstudio to run it?if so you should have a 'lost sync' logger which tells you how many times the trigger loses itself. Whenever the engine stumbles you can see the losing sync episodes piling up.
I used to get loads till I sorted the ht leads out. Now I just get a few now and again.

If you do what Per said and earth the hall sensor screen to the block then make sure the other end of the screen isn't earthed to anything.

Good luck, Keith.

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #32 on: February 05, 2017, 09:38:21 AM »
Hi keith many thanks for the input.
Now i have some points to test. The hall sensor cable screen ist conectet to eartg at ecu like you mentioned.
But will giv pers Suggestion  a try.
Will keep you informed

Michael

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #33 on: February 05, 2017, 09:53:49 AM »
Hi gys besides the ignition Problems i will kep on posting pics from the manufactoring process.
so here we go:

November 2012
did the angled gear for the Distributor. At first the plan was using a sigle coil and a conventional dizzy.
But later i decided to go go a more modern way with wastetd spark Coils.
I was afraid about the small distances in the dizzy cap.

I also did the Valve covers

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #34 on: February 05, 2017, 09:57:24 AM »
December 2012 i startet the engine holders.

some pics from machining and the ready pieces. This is a multiple side machining.

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #35 on: February 05, 2017, 10:04:48 AM »
2013 i was a Little lazy with the buuild so next parts start Decenber 2013

here i am working on the crankshaft. it is pressed together an uses roler bearing at the main and needle bearing at the rods.

One half is machined to spec the second half has left som 10th over to machie it ready after pressing together.


Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #36 on: February 05, 2017, 10:08:39 AM »
january 2014 i made the lower pulley for the cooling fan.
at the first time i planned to use a o-ring as belt but fortunatly i sorced a small angelt belt that look more scale
the belts are called 3m wide angeld belts

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #37 on: February 05, 2017, 10:12:24 AM »
february 2014 i worked on the dizzy. the cap is made from Hartgewebe donīt know the english Expression for this. maybee you know the Name pertinax itīs the same sort  plastic baut different filler.

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #38 on: February 05, 2017, 10:17:21 AM »
july 2014 the crank was ready. i was realy happy withe result. turned nearly free with only very small binding.
that went away after some turning the crank with an elektric drill

and a short Video


Offline Vixen

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #39 on: February 05, 2017, 02:35:00 PM »
Hello Michel,

I am following the build of your Bugatti project with great interest. I am full of admiration for your workmanship.

You have reached the part which is of great interest to me. I have been waiting to see how you would built the Crankshaft.

So you are using roller bearings and needle rollers in the same way as the original engine. I can see that you have assembled the crankshaft by pressing together the individual sections. Please explain how you achieved the perfect alignment between each section while it was being pressed together. There must be at least 16 sections that need to be in perfect alignment. I congratulate you on the achievement.

With an interference fit of a 10th, I don't think you can press a section apart or twist it to make corrections. I expect you do not get a second chance, the alignment must be perfect the first time. Please can you explain how you achieved this engineering miracle. Do you have photos for the fixtures and fittings you used and also the press you used.

I can see four holes in the centre of each crank web. Is this a clue to how you achieved the alignment? It would help me tremendously with my engine if you could provide additional detail of how you assembled your crankshaft. My Mercedes engine also has roller bearing mains and con-rods.

Thank you for sharing this excellent build with us. I wish I could help you with the ignition problem, however you are getting some very useful advice from the other MEM members. They must be some of the most knowledgeable miniature engine builders in the world. You are in safe hands

Thank you

Mike
It is the journey that matters, not the destination

Offline steamer

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #40 on: February 05, 2017, 02:50:40 PM »
I too am very interested in this solution.   The 917 12 lurks in the engineering phase, but I could be persuaded to go that way .....hmmmmm

Dave
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Damned ijjit!

Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #41 on: February 05, 2017, 04:10:13 PM »
Hi guys,
today i did some Research on the ignition and then i decide to test the System with motorcycle plugs.
These are with build in resistors with 4,7 kOhm.
Conectet the coilpaks with my wonderfull crocodile wires andf cranked the Bugatti.
Guess what..... Rocksolid rpm Signal. Not one single spike in the log.
Maybee it does matter where the resistor is located?

i added a resistor with 4,7kOhm in my sparkwires with not the expected effect.





Online michelko

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #42 on: February 05, 2017, 04:21:56 PM »
Hello Michel,

I am following the build of your Bugatti project with great interest. I am full of admiration for your workmanship.

You have reached the part which is of great interest to me. I have been waiting to see how you would built the Crankshaft.

So you are using roller bearings and needle rollers in the same way as the original engine. I can see that you have assembled the crankshaft by pressing together the individual sections. Please explain how you achieved the perfect alignment between each section while it was being pressed together. There must be at least 16 sections that need to be in perfect alignment. I congratulate you on the achievement.

With an interference fit of a 10th, I don't think you can press a section apart or twist it to make corrections. I expect you do not get a second chance, the alignment must be perfect the first time. Please can you explain how you achieved this engineering miracle. Do you have photos for the fixtures and fittings you used and also the press you used.

I can see four holes in the centre of each crank web. Is this a clue to how you achieved the alignment? It would help me tremendously with my engine if you could provide additional detail of how you assembled your crankshaft. My Mercedes engine also has roller bearing mains and con-rods.

Thank you for sharing this excellent build with us. I wish I could help you with the ignition problem, however you are getting some very useful advice from the other MEM members. They must be some of the most knowledgeable miniature engine builders in the world. You are in safe hands

Thank you

Mike

Hi Mike,
there is no big secret behind. As i wrote above i machined one disk completely ready to the specs, the other side was machined with 5/10 mm additional Diameter.
Then i pressed in the crankpin into the ready machined part. took this Setup in the lathe chuck and the other side disk into the tailstock.
Alligned the two picec and slightly stuck them toger, just enough that they dont fall appart. Took These assembly added some Loctite 648 into the bore and then pressed the parts together with the mill vise.
last step was take the whole part again into the lathe chuck, check runout and then turn the second disk to secs.
Unfortunatly i didnīt took Pictures of this process or they are lost. Donīt know.

I hope this discription helps you. If you Need more Information please ask.

Michael

Offline Vixen

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #43 on: February 05, 2017, 05:24:16 PM »
Hello Michael

Thank you for your reply, The information is very helpful for my Mercedes engine project.

I mistakenly thought you made the discs with an interference press fit, It appears you have bonded (glued) them together with Loctite 648. Is this correct?

Am I correct to think you make the second disc with a 5/10 oversize bore to give some small clearance for the Loctite 648 ?.

I am sorry Michael, but I did not understand what you meant by "check runout and then turn the second disk to secs."

After your press the two discs together in the vise, do you return the parts to the lathe to check the runout of the two parts and twist the two parts to correct any misalignment. How much time do you have to correct any misalignment before the Loctite starts to harden?

What is the diameter and width of the Loctite joint? and how wide are the discs?

Sorry to have so many questions. You will understand,  it is important for me to correctly understand the process of assembling a straight crankshaft

Thank You

Mike
It is the journey that matters, not the destination

Offline Roger B

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Re: Bugatti Typ 50 1/4 Scale model
« Reply #44 on: February 05, 2017, 06:05:28 PM »
I think that the difference when you carried out your test with the resistor plugs was that they were not grounded to the engine block but to the ignition modules, hence the possible requirement to have a good ground between the modules and the engine block.
Best regards

Roger