Small V8

[kcmillin]

The twins look Great Steve!!!

Excellent job.

When you milled down the tops of the cylinder liners did you take any material off the top of the head?

Kel

 

[stevehuckss396]

The twins look Great Steve!!!

Excellent job.

When you milled down the tops of the cylinder liners did you take any material off the top of the head?

Kel

Just enough to make new machine marks. .001 - .002 at the most.

 

[SAM in LA]

Steve,

Very impressive.

I look forward to reading your posts and seeing the progress that you have made.

Regards,

SAM

 

[Artie]

Steve, thats just amazing mate, absolutely gorgeous. Even if you went no further those would look brilliant on any desk or study as they are. Simply stunning.

Loving it. Please keep on it.

Cheers Rob T

 

[stevehuckss396]

I had to order metal so i decided to work on the cam. I did some math and created the cutting table. Then just to be sure I drew the cam in Alibre and mated it with the block. I started to rotate the cam in the block and watch the lobes to see if I had the orientation correct. Something was all screwed up and nothing was working out. I went back over the table and all looked good. I checked the 3D model and that looked OK. Took about 30 minutes to realize that I had the cam mated to the block backward.

What a butt head!!

All is well now and I can get to work on the fixture.

Thanks Everyone!!!

 

[stevehuckss396]

Hello All!

Made some progress on the crankshaft today. This piece is going to be a very tough piece to make. It is very fragile.


9 inch long piece of 1 X 1 inch 1018 CRS. The centers are drilled into both ends.

The OD is turned down. Then i marked with a grooving tool where all the crank webs will be. Everything except the spots where the marker is will be cut away in some form.

Then I moved off center for the first crank arm. This took forever. Have to cut real slow and not hurry or bad things can happen.

Thats all for now!!

 

[SAM in LA]

Steve,

It looks to me that you need some sort of follower to support the back side of you cuts so the crank does not twist up like a piece of spaghetti. Perhaps a spring loaded follower? I'm just guessing and have no experience to put behind my idea.

Good luck,

SAM

 

[Lakc]

Looks like a good start, brings back memories. I was going to start on a crankshaft today, my first time playing with 4140, and now that I remember all this I am wondering if I shouldnt just walk the dogs instead. It does require a whole lot of patience.

 

[don-tucker]

That looks very dodgy indeed Steve,I think i would have been inclined to rough them all out first leaving about 1/8" plus,just thinking out loud.There again looking at the work you have done so far you know exatly what you are doing

Don

 

[gbritnell]

Hi Steve,
Boy, I really hate to throw a wrench in your plans but why 1018? In my experiences with CRS, every time I take a cut it bends one way or another. I only use 1144 any more. It machines nicer than 1018 and there is no internal stresses thus the name 'stressproof'.

Another thing you might want to consider is doing your machining process like I did for my Holt crank. It can be found here:
http://www.homemodelenginemachinist.com/index.php?topic=5673.0
I found that by not relieving all of the throws at one time the material was much more rigid. On top of this you don't have to spend as much time on the lathe going, kachunk, kachunk, kachunk and hoping something doesn't catch and bend.

George

 

[stevehuckss396]

That looks very dodgy indeed Steve,I think i would have been inclined to rough them all out first leaving about 1/8" plus,just thinking out loud.There again looking at the work you have done so far you know exatly what you are doing

Don

If you rough them all out the crank will fold up like a book. I like to cut the first arm and then put a filler piece in the finished slot made to the .0005 thou. Then go to the next arm and then fill that one and so on. Looks bad, but works great.

 

[stevehuckss396]

why 1018?

Another thing you might want to consider is doing your machining process like I did

I had an old timer in my metal club tell me that the stress is in the skin. Once all the skin is gone the stress should be relieved. That is why I cut the OD of the crank first. I'll have to look into this 1144.

I do mine much the same as you only I cant pre-machine much on a 90 degree crank. I have to cut an arm 100%, then fill it with a piece of filler and then pre-machine the second one on the mill and then finish that one 100% and fill it, ect!

Also I wanted to finish all the arms and then do all the center bosses in one shot.

 

[stevehuckss396]

Well I just scrapped the crankshaft!

Hey G! I have to start over anyway. Where can I find a 1 inch square bar of the magical 1144?

 

[Lakc]

Well I just scrapped the crankshaft!

Hey G! I have to start over anyway. Where can I find a 1 inch square bar of the magical 1144?

Mcmaster has it, but it looks like its only available in round.

 

[gbritnell]

Hi Steve,
Jeff is right. It only comes as round but for a V-8 crank that's what I would work with anyway. Here's a link to the best price I could find for 1.25 dia.x 1 foot.
http://www.speedymetals.com/pc-1590-8239-1-14-rd-stressproof-or-equivalent-cold-finished.aspx
George

 

[stevehuckss396]

Hi Steve,
Jeff is right. It only comes as round but for a V-8 crank that's what I would work with anyway. Here's a link to the best price I could find for 1.25 dia.x 1 foot.
http://www.speedymetals.com/pc-1590-8239-1-14-rd-stressproof-or-equivalent-cold-finished.aspx
George

13 bucks for a 3 foot bar and 13 bucks to ship? OUCH!!

 

[kcmillin]

13 bucks for a 3 foot bar and 13 bucks to ship? OUCH!!

Ouch is right. Now is the time to get any more material you may need. They combine shipping on multiple orders. This will offset the cost of the shipping.

Kel

 

[Lakc]

I show $21 for a 3 foot length, after all the money I spent with them too

Metal supermarkets in Livonia doesnt carry it, which is too bad, as its right near my house. Metalmart in Sterling Heights? might be worth a call on Tuesday, as would Meco metals on Coolidge in Oak Park. Factory steel, which is open on Sundays, doesnt seem to carry it.

I would not recommend the 4140 route. While a fresh endmill left a beautiful finish, my lathe is not having much luck. Now I see why they offer it in leaded, dont know why I didnt buy that in the first place.

 

[stevehuckss396]

Hi Steve,
Jeff is right. It only comes as round but for a V-8 crank that's what I would work with anyway. Here's a link to the best price I could find for 1.25 dia.x 1 foot.
http://www.speedymetals.com/pc-1590-8239-1-14-rd-stressproof-or-equivalent-cold-finished.aspx
George

Did a search for metal suppliers in my area. Speedy metals is 5 miles from my house. I also have Metal Mart, Metal Express, and Industrial Metal all within 8 miles.

Phone calls will be flying tomorrow.

 

[putputman]

Steve, I think once you try 1144 you will really like it. It machines a little like cast iron. It is especially nice when using a parting tool as the swarf comes off in small chips rather than long cures.

The only negative I have heard about it is that it does not weld very well. Not a problem for model builders.