Another Edwards 5 Radial

[Rdean33422]

Yes Petertha that is something to keep in mind.
Thank you for the suggestion.

Ray

 

[peterl95124]

my success with cutting fins involves two ingredients, first an Iscar DGTR parting tool with a .055 width carbide insert (good looking fins at .100 pitch), and second a small squeeze bottle full of threading fluid with a blunt needle for application in the groove while it is being cut.
the Iscar parting tool has allowed me to cut fins on 1144-SP steel without any issues, and the threading fluid is a necessity regardless of what cutting tool you use or what material you're cutting.
yes, if you don't use threading fluid it will jam, you will shout expletives, the piece may be scrap, I always have a variety of oils on hand, here's the Iscar tool and my color coded oil bottles

 

[Rdean33422]

I found this rather ugly piece of aluminum in the (save it I might use it some day) drawer to make the cam housing.


Several hours of work later and the housing was completely machined with all the features except for the cam lobes.
Over on the CNC I cut side number one and it turned out great with nicely shaped lobes. Since there is an under cut the part has to be turned over to do the other side and the other two lobes. I flipped the part over and cut side number two and it turned out great also.


As I was admiring my handy work something didn't look right. When I flipped the part over I didn't get it clocked correctly in the vise so instead of the cam lobes being 60 degrees apart they were 90 degrees apart. In order to maybe salvage the housing I thought why not cut the housing flange off and re drill the holes offset by 30 degrees and here is the result.


The cam lobes are in the right place now but the ring gear is not exactly running true and that is very important.

Time to start over

Thanks for looking
Ray

 

[danallen]

I'm confused. Is this the cam or the cam housing? I see the ring gear which tells me cam but you are saying aluminum. In my plans the cam is steel and the housing is aluminum.

 

[peterl95124]

sometimes you can use a Woodruff Key cutter to make an undercut, and if you're just cutting aluminum you can turn the cutter to have a longer neck for longer reach, something I've done myself (yes you can usually turn HSS with carbide, not accurately because of the high forces required and consequent deflection, but just necking down a shank doesn't need to be exact)

 

[Rdean33422]

That's interesting Dan as I have seen some pictures that show the cams and the housing as separate parts. They are shown as one assembly in the plans I have and is made of steel. I have a different idea for the valve lifters so I think that aluminum should be fine.

Ray

 

[Rdean33422]

Happy Days
Practice makes perfect or just about as this time every thing worked out fine. The bumps are in the right places and everything fit as it should. I was going to polish it but then changed my mind as no one will ever see it but me.


And the other side.


I made a spacer from the crankshaft gear in the main housing to the cam housing bearing to get the height correct. I also made a spacer for between the two cam housing bearings and a long spacer for the nut to bear on. So when you tighten the nut there isn't any side load on the bearings. The shaft actually turns quite well with just one tight spot for every fourth turn of the crank.
I won't really know how well the gears mesh until I have the outer nose installed that has the outer crank bearing to hold everything in alignment.


Thanks for looking
Ray

 

[ajoeiam]

Happy Days
Practice makes perfect or just about as this time every thing worked out fine. The bumps are in the right places and everything fit as it should. I was going to polish it but then changed my mind as no one will ever see it but me.
View attachment 145923

And the other side.


I made a spacer from the crankshaft gear in the main housing to the cam housing bearing to get the height correct. I also made a spacer for between the two cam housing bearings and a long spacer for the nut to bear on. So when you tighten the nut there isn't any side load on the bearings. The shaft actually turns quite well with just one tight spot for every fourth turn of the crank.
I won't really know how well the gears mesh until I have the outer nose installed that has the outer crank bearing to hold everything in alignment.

Can't wait for the day when you get her all put together!!!

 

[Rdean33422]

Thank you ajoeiam

I got a late start today but things went remarkably well.

Cut a piece of new aluminum to length for the nose housing.


Over to the lathe to reduce the diameter almost 1".


So after a few hours turning on the lathe and a big pile of chips I found this.


All shined up.


I was concerned that the rough spot in the timing gears would get worse after the crank shaft was supported properly but it was just the opposite. The gears even feel better now and I think a little spinning on the lathe will solve the rest of the problems.
Very happy with the results today.

Thanks for looking
Ray

 

[gilbycoath]

my success with cutting fins involves two ingredients, first an Iscar DGTR parting tool with a .055 width carbide insert (good looking fins at .100 pitch), and second a small squeeze bottle full of threading fluid with a blunt needle for application in the groove while it is being cut.
the Iscar parting tool has allowed me to cut fins on 1144-SP steel without any issues, and the threading fluid is a necessity regardless of what cutting tool you use or what material you're cutting.
yes, if you don't use threading fluid it will jam, you will shout expletives, the piece may be scrap, I always have a variety of oils on hand, here's the Iscar tool and my color coded oil bottles

 

[gilbycoath]

Thanks Peter for the information on the Iscar DGTR parting tool 0.055.
I visited the Iscar site and couldn't find it. ( a huge site mostly devoted to automatic machines ) there are hundreds of tools.
I also looked at a lot of tool suppliers with no Luck.
If you remember or know where you got it from could you post it please.
Ron.
ACT Australia.

 

[ajoeiam]

Thanks Peter for the information on the Iscar DGTR parting tool 0.055.
I visited the Iscar site and couldn't find it. ( a huge site mostly devoted to automatic machines ) there are hundreds of tools.
I also looked at a lot of tool suppliers with no Luck.
If you remember or know where you got it from could you post it please.
Ron.
ACT Australia.

Hmmmmmmmmmm - - - - just tried - - - used a search "Iscar + DGTR" that would give you the specific part number(s).

As to finding a supplier - - - - it used to be you could use the 'Yellow Pages" (North America - - - dunno if its same down under) - - - that doesn't work so good here any more. I find its harder to find a distributor than to find the information on the tooling (today all the info is online and I believe they still LOVE to hand out huge piles of catalogs - - - there was tons of info in those things!!!!!!).

HTH

 

[Majormallock]

Hi Guys, I understand the problem. The drawing calls up 40 thou fins, , for my version I ground a thin parting tool. It worked but very slowly. So I bought some 40 thou slitting saws, ganged 3 together and put them in the mill and used my rotary table. That worked well. I liked your cam ring. Better than mine. Good luck with it

 

[josodl1953]

Ray, are you planning a surface coating such as hard anodizing for the cam lobes ? This part is subject to severe friction and you don't want wear particles circulating through your engine...

Jos

 

[Rdean33422]

I haven't decided yet just what the lifters will look like. I would like to make them from 1/4" brass with a roller bearing on the end but I haven't come up with a way to keep them from turning side ways. I thought of making them from 1/4"square brass but a square broach is so expensive and I haven't had any luck making one.
Do you have any ideas?

Ray

 

[Peter Twissell]

Hi Ray,
A couple of ideas to stop your lifters from rotating:
Most simple is to offset the roller from the lifter centre, so that it castors. Note that this will produce a small change to the cam timing.
Another method would be to put a flat on one side of each lifter and fit a ring into the housing between the two rows of lifters to sit against all the flats.

 

[peterl95124]

I have no recollection of where I bought the Iscar tool, here's a photo so you know what to look for, its their "DO-GRIP" model, I suspect DGTR means "do grip tool righthand"
under the insert are the number 031 and 11735 which don't mean anything to me
9.5B is the shank size (9.5mm ~~ 3/8")
1.4mm is the width of the cutter insert tip, not sure what D20 means but may be related to corner radius or one of the cutter angles
judging by the color of the insert I guess its TiCN coated, and hasn't worn even after making over a dozen cylinders out of 1144-SP (I love that alloy!)

(considering how long I've had it I'm guessing I got it from Rutland Supply, which sadly no longer exists)

 

[Steamchick]

Found them here...
https://www.iscar.com/eCatalog/item.aspx?cat=2301264&fnum=77&mapp=TG&app=51&GFSTYP=M&isoD=1K2

 

[Steamchick]

This is my latest "best buy" for parting tools...
https://www.chronos.ltd.uk/product-...mp-type-parting-tools-with-chipbreaker-blade/ It has a groove up the middle of the top surface of the blade, which causes chip breaking and hence swarf quickly escapes the groove. Means I can go all the way through the workpiece in a single continuous cut, without having to withdraw to clear swarf, or risk binding from swarf getting wedged down one side of the tool and causing tool breakage or workpiece damage. The v-groove also avoids side thrust - it actually appears to centre straight so every parted face is true and flat - unlike the previous similar tool with just a single angled top face for clamping.
These tools are easy to resharpen - just a single touch on the stone is adequate, although a rare task.
Well worth the investment as all my other parting tools are now redundant!
K2

 

[josodl1953]

Hi Ray,
Maybe it is an idea to make oval cam followers. Slots can easily be made with end mills ,see A. Finding rollers that small will be a challenge I think. Maybe you should consider using separate liners for the cam lifters bolted on to the cam housing, see B. This gives you more supporting length for the lifters. Another advantage is that, in case you mess up milling a slot, you don't have to make a new cam housing but only another liner.

Just a thought......

Jos