Author Topic: Holt 75 from Germany  (Read 16701 times)

Offline michelko

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Re: Holt 75 from Germany
« Reply #120 on: May 27, 2024, 11:05:28 AM »
Hi,
just started with the intake manifold. It is made from two pieces soldered together.
First milled the inner passage on both pieces, then firs touter contour.
the mill ran quite a while for this.
Hope the soldering will work well.
The milling marks will be filed and sanded.

Offline gbritnell

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Re: Holt 75 from Germany
« Reply #121 on: May 27, 2024, 11:40:29 AM »
When I redesigned the engine drawings one of the more complex fabricating jobs was the manifolds.  With the originals being cast aluminum and having all curved shapes I designed them to be fabricated from pieces of steel or brass and silver brazed together.
Talent unshared is talent wasted.

Offline michelko

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Re: Holt 75 from Germany
« Reply #122 on: May 30, 2024, 06:00:39 PM »
Hi Guys,
the intake manifold is ready. Just a little bit of sanding.
Soldered the two pieces together and then again onto the mill.
After the CNC action i filed and sanded the machining marks.
Maybee i will get it glas blasted to look more like casting.
Next will be the exhaust.

Cheers Michael

Offline Vixen

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Re: Holt 75 from Germany
« Reply #123 on: May 30, 2024, 06:48:33 PM »
Hello Michael

Beautiful 3D sculpture. You should very pleased with the result.

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Admiral_dk

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Re: Holt 75 from Germany
« Reply #124 on: May 30, 2024, 10:04:48 PM »
I agree with Mike - beautiful result  :praise2:

Per  :cheers:

Offline gipetto

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Re: Holt 75 from Germany
« Reply #125 on: May 30, 2024, 10:16:49 PM »
I thought you were going to leave the billet block bolted to the engine. that looks like an oem part.

Offline gbritnell

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Re: Holt 75 from Germany
« Reply #126 on: May 30, 2024, 11:43:13 PM »
Truly outstanding results!  It looks just like the manifold on the full-size engine.
Talent unshared is talent wasted.

Offline Dave Otto

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Re: Holt 75 from Germany
« Reply #127 on: May 31, 2024, 01:15:39 AM »
Nicely done!

Dave

Offline Zephyrin

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Re: Holt 75 from Germany
« Reply #128 on: May 31, 2024, 08:55:56 AM »
great results, outstanding carving of this manifold inside and outside from 2 solid blocks, inspiring thread !
what is the wall thickness at the end, how thick did you dare?
« Last Edit: May 31, 2024, 09:00:10 AM by Zephyrin »

Offline michelko

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Re: Holt 75 from Germany
« Reply #129 on: May 31, 2024, 11:27:31 AM »
great results, outstanding carving of this manifold inside and outside from 2 solid blocks, inspiring thread !
what is the wall thickness at the end, how thick did you dare?
its still quite a heavy lump. wall thikness is about 3mmm

Michael
P.S.
Thanks to all for the kind words.

Offline Roger B

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Re: Holt 75 from Germany
« Reply #130 on: June 01, 2024, 11:27:36 AM »
Excellent  :praise2:  :praise2:  :wine1: I was interested to see how you were able to keep the manifold fixed to the milling table until almost the end.
Best regards

Roger

Offline michelko

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Re: Holt 75 from Germany
« Reply #131 on: June 05, 2024, 03:03:28 PM »
i made a mistake on cutting the stock pieces for the exhaust to length, soi had to order new ones. Waiting for them i made the spark plugs.


Offline michelko

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Re: Holt 75 from Germany
« Reply #132 on: June 05, 2024, 03:05:09 PM »
Would it be better to leve the electrode flat or should i grind them like a needle?

Offline Admiral_dk

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Re: Holt 75 from Germany
« Reply #133 on: June 05, 2024, 07:57:42 PM »
I would leave them flat - as it is the Edge that the Spark starts from (and why very round electrodes can give you problems with a worn sparkplug).   :zap:

Nice looking plugs  :ThumbsUp: 

Per    :cheers:

Offline gbritnell

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Re: Holt 75 from Germany
« Reply #134 on: June 06, 2024, 12:27:42 PM »
Great job on the spark plugs. Yes leave them square.
Talent unshared is talent wasted.

 

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