Gotta crankpin question.

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You can't drill the crank. You need to coaxial indicate it in and than bore it to an interference fit on the pin. It depends on wall thickness left to the outer edge of the crank wheel as to whether it will still maintain a good press fit once the pin is installed.
 
Z.hb71 said:
The Piston is the same as they use, I think ALX has a custom rod which they will probably over charge and it's all the way in Italy, theyre probably not willing to share they're secrets but even if I tried they won't respond!!

Can't drill the crank cuz Ive got to remove meterial from
The inside of the crank so if I drill it, it will be really weak. I personally can't make a rod myself cuz I'm not experienced and don't have the resources. I prefer to buy a rod but if it comes to it, I'll splurge and get me made a billet aluminum rod

Can't drill the crank cuz Ive got to remove meterial from
The inside of the crank so if I drill it, it will be really weak. I personally can't make a rod myself cuz I'm not experienced and don't have the resources. I prefer to buy a rod but if it comes to it, I'll splurge and get me made a billet aluminum rod
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Not Aluminum. Even Billet Aluminum wouldn't be strong enough . Pretty sure rods are normally made from steel or titanium .
 
TODD said:
You can't drill the crank. You need to coaxial indicate it in and than bore it to an interference fit on the pin. It depends on wall thickness left to the outer edge of the crank wheel as to whether it will still maintain a good press fit once the pin is installed.
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Drill and bore, both enlargening a hole. Can't do it
1Coopgt said:
Not Aluminum. Even Billet Aluminum wouldn't be strong enough .
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So tool steal or titanium ?
1Coopgt said:
Not Aluminum. Even Billet Aluminum wouldn't be strong enough . Pretty sure rods are normally made from steel or titanium .
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EDIT: found the rod I wanna use, it's made by PRO X, for a Honda mb50, partnumber 03.1003
Here here's the specs Screenshot_20181227-192152.webp
 
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Z, your talking all one-off parts now. Why go this route? I understand the "I'm in too deep" concept but it seems like a dark tunnel that your going down. What are you going to do if a part needs replacing later on? You have way bigger gonads than me. If I couldn't source the needed parts and put it together I wouldn't even contemplate doing this. I'm good with my hands and building things, as I see you are, but the type of tools needed to do what you need done is way out of my and most scope. Maybe if you go talk to one of the machinist they will be into RC also and he will be way into what you are looking into doing and offer some guidance.
 
crucialRC said:
Z, your talking all one-off parts now. Why go this route? I understand the "I'm in too deep" concept but it seems like a dark tunnel that your going down. What are you going to do if a part needs replacing later on? You have way bigger gonads than me. If I couldn't source the needed parts and put it together I wouldn't even contemplate doing this. I'm good with my hands and building things, as I see you are, but the type of tools needed to do what you need done is way out of my and most scope. Maybe if you go talk to one of the machinist they will be into RC also and he will be way into what you are looking into doing and offer some guidance.
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Yes your right, I'm trying my best to avoid 1 off stuff. A custom crankpin is no problem just a custom rod like u said is a pain in the ass when time to replace. So I've found that Honda rod that looks good, right size except for the custom pin needed. I'll talk to a machinist Soon. ??
 
1Coopgt said:
Not Aluminum. Even Billet Aluminum wouldn't be strong enough . Pretty sure rods are normally made from steel or titanium .
Click to expand...

There are plenty of aluminum rods out there. Even top fuel dragster run them. It however may not be the best choice for this application.

Think if the crank and rid mentioned above could be had easily I'd be going that way. I have a great machine shop here close(used to work there) and it's expensive for custom work. If the correct crank and rod could be had it may end up being the cheaper rout to go.
 
Seandonato73 said:
There are plenty of aluminum rods out there. Even top fuel dragster run them. It however may not be the best choice for this application.

Think if the crank and rid mentioned above could be had easily I'd be going that way. I have a great machine shop here close(used to work there) and it's expensive for custom work. If the correct crank and rod could be had it may end up being the cheaper rout to go.
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I stand Corrected . (y)https://www.enginelabs.com/news/tech-quickie-what-makes-a-top-fuel-connecting-rod-special/ Kind of explains why when a Top Fuel Dragster blows up it always pretty spectacular .
 
mark35 said:
Hi Zee I have just been speaking with Alx and the crank is not moddefied which I did not think it would be.
Here is the crank he usesView attachment 48359
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Ok, I'll see about that. Thanks for the info Mark ?
EDITTTTTTT: it's a 10 pin, poop! Atleast I'll ask how wide it is so I can find a rod that wide.
EDDDDDIIIIIITTTTTTT AAGAAIINN: it's 13mm wide so like 1mm on each side of the rod when installed on the piston. The rod I want is 13mm wide so I'm on the right track (for once) ? just the pin situation, I think I'll just get one made, seems like the only/best option
 
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