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stevehuckss396 said:
I wouldn't. I never feel guilty when it's over 100F and we are at 75F. My brother inlaw called from SC laughing. I told him to call back in August.

;D
Oh You speak wisdom my friend....same here!

Dave
 
Hi Dave,

I don't have words again... better... I have.. wonderful!!!

:bow: :bow:

Cheers,

Alexandre
 
stevehuckss396 said:
Then it was spot, drill, ream, repeat.

Steve, did you change the bits three times for every piston? Would it not be possible to spot them all, then drill them all, the ream them?

Also, what is holding the piston onto the fixture?

Kel
 
kcmillin said:
Also, what is holding the piston onto the fixture?

Kel
I was wondering that myself. Then I thought that if he was drilling exactly on center, it might not need to be more then his left hand.
 
kcmillin said:
Steve, did you change the bits three times for every piston? Would it not be possible to spot them all, then drill them all, the ream them?

Also, what is holding the piston onto the fixture?

Kel

I did all 3 and then went to the next piston. Once you break thru with the drill bit the piston is captured on the fixture so may as well just ream it before wiggleing it off. Wiggling it off can get to be a little bit of a pain because it dont wiggle much if any at all.

I just slip them on, tap it a few times, and hold them on with my finger. They are snug and don't move at all.
 
Steve

I have been following the thread from the beginning - absolutely brilliant.

There did not appear to be a backstop in the chuck when you machined the piston tops. Is this something that is of no consequence, or will final machining be carried out after measuring piston heights on a fully assembled engine? (Or with at least the con rod connected to crank and pistons).

Pete
 
Spurry said:
Steve

I have been following the thread from the beginning - absolutely brilliant.

There did not appear to be a backstop in the chuck when you machined the piston tops. Is this something that is of no consequence, or will final machining be carried out after measuring piston heights on a fully assembled engine? (Or with at least the con rod connected to crank and pistons).

Pete

The pistons are all the correct height to the drawing as of right now. Now I will make a test rod from the drawings and check the piston height. If any adjustment needs to be made, the rod will be adjusted to set the final piston height. I'm shooting for flush with the deck height for a compression ratio of 5.335:1
 
Thanks for that. My comments were based on a procedure I had read about for blueprinting racing engines.

Keep up the good work.

Pete
 
I decided to have some fun today and make a pattern for some thing I have been thinking of casting.

I used some lexan that was given to me. I pinned two pieces together so I can cast in sand.

Started roughing it out with a 1/4 inch cutter.

DSCN1175s.jpg


DSCN1177s.jpg


DSCN1181s.jpg



Then I made some horizontal passes with a 1/8 inch ball nose. Can see more detail coming out.

DSCN1189s.jpg


DSCN1191s.jpg



Then vertical passes .006 on center for a few hours.

DSCN1192s.jpg


DSCN1199s.jpg



Then to the manual mill to remove the extra off the bottom

DSCN1202s.jpg



Blower.jpg
 
Here is where you CNC guys start to make us jealous.
The likely forthcoming helix definately will. :-[
 
stevehuckss396 said:
Sorry to disappoint but they will be 3 lobe straight.

No disappointment here Steve. :big:

Kel
 
looks like a new manifold coming up... I was wondering a few months ago if someone would try this... I have been an avid reader of this thread since the start way back in June last year, its just stepped up a notch!

Thanks Steve.

P.s. I am assuming this is scaled for the current build??
 
Artie said:
looks like a new manifold coming up... I was wondering a few months ago if someone would try this... I have been an avid reader of this thread since the start way back in June last year, its just stepped up a notch!

Thanks Steve.

P.s. I am assuming this is scaled for the current build??

The sad thing is I cant modify an existing intake manifold. I will be making a new one. I'm going to carry on with the carburated build. I would like to get that one running. Once the first is running, the second one will get a blower.

I must be out of my mind!!! What the heck am i thinking?
 
stevehuckss396 said:
I must be out of my mind!!! What the heck am i thinking?

Thinking? OUTSIDE the box my man, outside the box... and Im bloody glad you are.... :bow:
 
Steve
u just blew my mind ;D
If I thought I could handle the computer side Id love to go CNC :bow:
Pete
 
stevehuckss396 said:
The sad thing is I cant modify an existing intake manifold. I will be making a new one. I'm going to carry on with the carburated build. I would like to get that one running. Once the first is running, the second one will get a blower.

I must be out of my mind!!! What the heck am i thinking?


Rof} Rof}

OK....lets recap...we spend hours of of time wittling out an untold number of parts to build a miniature V8 engine that by all accounts no one understands what we are going to do with or why ( see the thread recently on "how do you answer the question") and you think putting a blower on it going over the top?



Dear god man I think its b(*#* Brilliant! Can't wait to see it!

Dave
 
That blower is a pretty cute idea. How come you're casting it? Seems like you've almost got it done in plastic. Had that been aluminum it'd be done. I've casted a lot of aluminum. The trouble I've had is trying to end up with aluminum that was machinable after it was cast. I always used scrap in the melt and that most likely didn't help. Seemed the casting was always soft and gummy. It didn't lend itself to machining. We used some kind of flux in the melt too to float the dross. Without the flux I just had a mess of pits and slag. And the temperature of the melt was important. I poured about 1300 F. If I got it too hot the melt was ruined, too cold and it wouldn't run. Shrink was an issue too. You need to use large gates so the cavity has a ready supply of molten metal. For sand I used Pextobond I think. It worked well but finding small quantities might be troublesome. Have fun.
Guys that can crank out good castings one after another know what they're doing.
 
jpeter said:
That blower is a pretty cute idea. How come you're casting it? Seems like you've almost got it done in plastic. Had that been aluminum it'd be done. I've casted a lot of aluminum. The trouble I've had is trying to end up with aluminum that was machinable after it was cast. I always used scrap in the melt and that most likely didn't help. Seemed the casting was always soft and gummy. It didn't lend itself to machining. We used some kind of flux in the melt too to float the dross. Without the flux I just had a mess of pits and slag. And the temperature of the melt was important. I poured about 1300 F. If I got it too hot the melt was ruined, too cold and it wouldn't run. Shrink was an issue too. You need to use large gates so the cavity has a ready supply of molten metal. For sand I used Pextobond I think. It worked well but finding small quantities might be troublesome. Have fun.
Guys that can crank out good castings one after another know what they're doing.


I'm casting it because it is just another hobby of mine. Other than all you say above, it should be easy. I have the sand, flux, ect, ect. I'm going to waste a few saturdays pouring them and see if I can get a few good ones. Never know if there might be another club member that builds a V8. Maybe they would like to machine one up.

Did you heat treat the aluminum after you poured it?
 
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