Silver Bullet in progress

stevehuckss396 · Apr 27, 2010

Mosey said:
I have the water pump almost done and will put up some pics shortly.

Do you think that making a multi-cylinder engine from billet is such a great idea for a beginner?

I look forward to seeing the pics. Nothing wrong with making a billet engine. No castings to screw up.

Mosey · Apr 27, 2010

Sorry, I only meant that the parts outside the block are from billet, as it is a casting kit of course.

el gringo · Feb 20, 2011

Chuck,
My silver bullet is coming together nicely. I am going to make the cam next.
My question is what holds the cam in place axially and why the split front brg? Bob says it is for easy removal? This is my fourth Bob Shores engine and the beat goes on.......

Ray M

Mosey · Jul 30, 2011

Well, I finally am back to work on the Sllver Bullet.
I am working on the fan, which has been duly reported on another topic. Here are some pics of my first attempt to mill a 9 blader. Critiques and comments are welcome. This is how rank amateurs do it.
I am using the universal table tilted to 30 degress, Sherline RT, and 2 mini-clamps. I think I need the elves to come in as this is tiny stuff. I had to align the center of the RT with the center of the mill spindle at the height of the top of the work piece. I have to move the clamps as I rotate the table to clear them.

stevehuckss396 · Jul 30, 2011

Looking good so far!!

metalmad · Jul 30, 2011

go Mosey :bow:
Pete

Mosey · Jul 30, 2011

Well, nobody rose to the question implicit in my setup. When the table is tilted, then the axial center of the RT and the work is only aligned with the spindle axis at 1 point where the 2 axis cross. I set it up to cross at the top surface of the workpiece.
Now I plan to drill a small center hole in the fan hub, flip it over and realign with the spindle axis at the new top surface of the hub. Then mill the other side of the blades. Also, have to align the fan blades so that they are milled to match the other sides. Piece of cake right?

Comments are invited.

stevehuckss396 · Jul 30, 2011

Mosey said:
When the table is tilted, then the axial center of the RT and the work is only aligned with the spindle axis at 1 point where the 2 axis cross. I set it up to cross at the top surface of the workpiece.

What?

I trust you have it under control.

Mosey · Jul 30, 2011

Trust me! The check is in the mail.

gbritnell · Jul 30, 2011

Hi Mosey,
I have been following the conversation between you and Steve about fans and would just like to interject my thoughts. While I certainly applaud the effort that you are putting into your fan I think that you are making more work for yourself than necessary.
You could cut the fan out of a piece of flat stock and then as was mentioned, make a curved buck from a piece of wood and press the curve into the blades. Drill the center hub area for mounting holes and screw it to a machined pulley.
That's the way the full sized ones are made,(before plastic). Attached is a picture of my Holt fan. It was made as I describe.
As far as your setup, it looks fine to me although instead of moving the big clamps around I think I would have made some small ones that could be moved more easily.
gbritnell

Mosey · Jul 30, 2011

You're right, of course. I did want to see if I could mill it, but I think I will follow you're suggestion.
Thanks.

Mosey · Jul 31, 2011

gbritnell said:
Hi Mosey,
I have been following the conversation between you and Steve about fans and would just like to interject my thoughts. While I certainly applaud the effort that you are putting into your fan I think that you are making more work for yourself than necessary.
You could cut the fan out of a piece of flat stock and then as was mentioned, make a curved buck from a piece of wood and press the curve into the blades. Drill the center hub area for mounting holes and screw it to a machined pulley.
That's the way the full sized ones are made,(before plastic). Attached is a picture of my Holt fan. It was made as I describe.
As far as your setup, it looks fine to me although instead of moving the big clamps around I think I would have made some small ones that could be moved more easily.
gbritnell

Stainless, or Alum? Gauge?
By the way, those clamps are only 1-1/2" x 3/16" thick. I got them from an auction and they are hardened. Very nice. Smaller??

Dave G · Jul 31, 2011

Hi Mosey, I built the Silver Bullet about 10 yrs ago and it has been a good runner. I built the radiator to Bob's design and it has a 4 blade fan for cooling which it doesn't do very well. Mine will get quite hot (200 degrees) fairly quickly. I think the radiator is of sufficient size but the fan doesn't pull much air. A good multi blade fan that is shrouded would help a great deal.
The water pump is built to Bob's specs also using pinion stock with an o-ring between the pulley and housing for sealing which works alright. It seems to move plenty of coolant as my coolant lines are clear and you can see the coolant flow. I don't normally run my engine long, maybe for 5-8 mins before shutting off. The Silver Bullet was my first IC engine build and remains one of my favorites. I hope you will enjoy yours as much as I have mine. Dave

Mosey · Jul 31, 2011

Dave G.,
How nice of you to tell me about your SB! Encouraging.
I am feeling my way through slowly and having a great time. I had to get my machines and my skills up to snuff, so that has slowed me down as well, but I'm chugging now.
I will take pictures so the other newbies can go along with me.
I will definitely make a good multiblade fan, and think about shrouding it.
I have the pump made and am making the gears from scratch, which I enjoy.

:

Mosey

gbritnell · Jul 31, 2011

Hi Mosey,
I would stay with aluminum. Less rotating mass. As far as gauge, I would say around .032 should be more than sufficient for anything up to 2.00 diameter. Once the curve has been pressed into it, it will become much stiffer.
gbritnell

Mosey · Aug 1, 2011

Dave G said:
Hi Mosey, I built the Silver Bullet about 10 yrs ago and it has been a good runner. I built the radiator to Bob's design and it has a 4 blade fan for cooling which it doesn't do very well. Mine will get quite hot (200 degrees) fairly quickly. I think the radiator is of sufficient size but the fan doesn't pull much air. A good multi blade fan that is shrouded would help a great deal.
The water pump is built to Bob's specs also using pinion stock with an o-ring between the pulley and housing for sealing which works alright. It seems to move plenty of coolant as my coolant lines are clear and you can see the coolant flow. I don't normally run my engine long, maybe for 5-8 mins before shutting off. The Silver Bullet was my first IC engine build and remains one of my favorites. I hope you will enjoy yours as much as I have mine. Dave

Dave,
Been thinking..too late for this head, but I've been wondering about finning the head, now I have an excuse, to cool it. Humm?
Mosey

Mosey · Aug 6, 2011

gbritnell said:
Hi Mosey,
I would stay with aluminum. Less rotating mass. As far as gauge, I would say around .032 should be more than sufficient for anything up to 2.00 diameter. Once the curve has been pressed into it, it will become much stiffer.
gbritnell

I am giving it a go. What do you think of this blank?

Mosey · Aug 6, 2011

And now I have formed the fan blades in a die, using a form I turned. I next have to straighten the blades and clean up and polish. Then I will turn a little hub cap, and bolt it to the fan hub with 3 1-72 bolts. Hopefully I can make it look less crude, just like the big guys.
Critique is welcome.