PeeWee V4 slow build

[gus]

Hi Cogsy,

Very well done Carb!!! Beats mine.

 

[Cogsy]

I've been delaying attempting the camshaft as I still haven't worked out a way to mount the electric motor to my power hacksaw - it's an old motor that doesn't have any mounting points or holes. I think it may have been clamped originally. Anyway, I had to beak out my manual hacksaw and attack a piece of 1/2" plate and some 1" square bar I found at the back of the shed. More energy than I like to expend later, I had the rough-sawed bits.



A bit (lot) of milling later, plus a bit of drilling and a little tapping, and the fixture is almost done.



Here I've added the ali disc for the degree wheel and it just needs the bushes to secure the cam blank.



And finally the cam blank itself. The blank was more difficult to make than expected. I've discovered an issue with my lathe that I had to work around and I had to turn it in very small sections at a time.



Now I just need to actually cut the lobes. Fingers crossed I'll be attempting to get it done in the next couple of days but no promises.

 

[Davewild]

Hi Cogsy.

Great work, I'm at a standstill with mine, work keeps getting in the way, any update on your castings?

 

[Cogsy]

Hi Dave,

Still waiting on the castings unfortunately. Word is the foundry will be trying another pour in the next couple of weeks. Fingers crossed it goes well - I'm catching up to the point that I really need them soon.

So far it's been a really fun and challenging build. I look for new posts about yours all the time.

 

[Davewild]

Hopefully you will get an update soon, likewise I check out your build regular as I can offshore, I'm home now for a week trying to get the crankshaft finished, will be posting soon!!!

Hi Dave,

Still waiting on the castings unfortunately. Word is the foundry will be trying another pour in the next couple of weeks. Fingers crossed it goes well - I'm catching up to the point that I really need them soon.

So far it's been a really fun and challenging build. I look for new posts about yours all the time.

 

[Cogsy]

For my attempt at turning the cam lobes, I set the cam fixture between centres in the lathe. Actually I put it between a live centre in the tailstock and a nice big, pointy countersink in the lathe chuck :hDe:. The main reason I used the countersink instead of an actual centre was because I don't have any drive dogs. I contemplated making something up but decided to see if the countersink would provide enough drive. It worked better than expected - not only did it drive just fine, but if I ever made a grave error and ran the cutting tool into somewhere it wasn't supposed to be (like the side of a lobe or the end of the fixture) the slight 'crash' would overcome the driving force of the countersink and no damage would occur. Don't ask me how I know this though :wall:.

Here's the cam after the first of 72 'sides' has been cut. This 'side' took a whopping 50 minutes to cut. Luckily the rest were much quicker. The black marker on some lobes was just to help me keep track of which lobes not to cut for each 'side'.



After a bit more progress it started to take shape. As I made the fixture in 3 pieces I was able to easily shim either of the end pieces to perfectly align the cam blank in the lathe. Here you can see the piece of 5 thou feeler guage poking out from under the drive end. I'm not sure if I made the fixture slightly out or if the 5 thou was the inaccuracy of the 3 jaw chuck and countersink combined. It doesn't matter though - the shim took care of it.



Here's the cam after all the cuts on the lathe were completed (about 1/2 an hour ago). I still need to blend all the facets and round the nose transitions, then give it all a good polishing up, but my wife called me inside to make dinner so that'll be tomorrows job.



And a final shot to show the size of it. Most of the back portion is only for holding it in the fixture and will be removed.

 

[gus]

Looks like a very good looking cam shaft coming.

Thanks for posting. I knowing nothing with turn cam shafts on a lathe. The two cylinder inline engine require such cam shafts.

 

[stevehuckss396]

hold the cam between centers in the lathe to file the nose profile. The lathe does a good job of holding the shaft and you can rotate it easily as needed. Then just pinch the lobes with a piece of 150 or so grit sandpaper and run the lathe forward and then backwards for just ten seconds or so and the facets will disappear.

Nice job on the cam. How long did it take to make. I remember mine taking about four and a half hours after the fixture and blank were done.

 

[Cogsy]

Thanks for the tips Steve, they'll make it easier for me.

Not including making the fixture or the blank, and also not including setting the blank up in the lathe and grinding a few different HSS tools until I worked out the right shape, it took me about 7 hours spread over 2 days - I think maybe I should have run it at more than 300 RPM and it would have saved some time but I wasn't in a hurry.

I didn't want to stop on day 1 but my back was absolutely killing me and I had no choice. I also think I might have held my breath the whole time. With every cut I was sure I was going to mess it up somehow, and the closer I got to finished the more nerve-racking it got. Now that's it's all over I can sit back with a massive sense of achievement and say it was fun!

 

[Davewild]

Beautiful, beautiful, beautiful, well done, was it as bad as you thought? You can't have many pieces left now? My crank is coming along nice hopefully I will post before the weekend.

Dave

 

[Cogsy]

Looks like a very good looking cam shaft coming.

Thanks for posting. I knowing nothing with turn cam shafts on a lathe. The two cylinder inline engine require such cam shafts.

Gus, there is a fantastic document in the downloads section by Steve Huck that explains the procedure in great detail. You'll have to do a little math but if you follow the steps you'll have no problems. Here's the link.

 

[Cogsy]

Thanks Dave. It wasn't a bad job at all, just a little nerve-racking keeping track of all the steps and trying hard not to run the tool into places it wasn't supposed to go. To be honest, once I recover from making this one, I might make another cam just for display.

What's left to make (in random order) : all the castings will need machining, liners, the rods, pistons, rings, wrist pins, valves, guides, retainers, gears (modifying not making), flywheel, adapter plate, intake manifold, exhausts, dipstick, various external fittings, engine mounts, radiator and re-do a dizzy cap. Then it's just mounting the whole lot to something and fitting an ignition. Really not as much as I thought once I see it all written down. I may just complete this thing this year!

Good luck with the crank, I'll be keeping an eye out.

 

[gus]

Hopefully you will get an update soon, likewise I check out your build regular as I can offshore, I'm home now for a week trying to get the crankshaft finished, will be posting soon!!!

Hi Dave,

Where are you now??? Loyang Marine Base or Batam???

Am glad you can get on to HMEM while overseas.

Take care.

 

[e.picler]

Congratulations Cogsy!
Very good job, you are progressing well on your PeeWee. For sure I will use your thread as reference when building my PeeWee (next project).
I also machined the lobes on the blank of the Tiny 4 inline this weekend. I did that on the CNC milling machine, it took me more than 2 hours to machine the 8 lobes because I used a very conservative (slow) feed rate.
I will post pictures before the end of the week.

Edi

 

[Cogsy]

Thanks Edi. I've been watching your Tiny build and I think I may have to build one in the future as well. Great looking engine and you're doing a nice job on it.

 

[Cogsy]

I chucked up a piece of scrap ali and bored it to suit the hub of the distributor gear so I could bore it out. As per Swifty's suggestion I drilled and tapped for an M3 set screw to secure it as well.



Then I pressed it onto the cam, with a bit of loctite for safety as well. The next step was supposed to be turning the O.D. of the gear hub to accept the rear cam bearing, but due to a slight error in the plans, I didn't have the bearings on hand. The plans call for the cam bearings to have a 0.187" I.D. but the front of the cam is 0.250" and the shaft the gear presses onto is 0.187" meaning the entire hub would need to be machined away to fit the bearing. I've got the correct bearings ordered and I should have them next week, so I continued on to the other gears.



Again I used some scrap ali as a fixture and this time made the hole a tight tap-in fit. I didn't use a set screw and was hoping I could part through the fixture and the hub as well, as I needed to remove the Hub and I didn't want to try holding the gears by the teeth. It worked reasonably well and only required a little clean up and the teeth were untouched.



Here's the gear-train all completed, except for a bit of polishing. I was a bit disappointed with the cam gear. I had to reduce the hub length and drill/tap for a new set screw. The unfortunate thing is the old set screw hole was not completely removed and looks unsightly. It won't affect anything, and will be hidden inside the engine, but I'll know it's there.



Now I have a little clean-up of some parts and a bit of polishing, then I think I'm pretty much stuck waiting for castings.

 

[Cogsy]

For a bit of fun I decided to try and whip up a Holley-style air cleaner for the Peewee. Not sure I'll use it while it's running but should keep the crud out of the carb when it's on display. I had fun making the tri-corner 'nut' and it takes me back a few years when this style was all the rage (including on my car).

 

[michael-au]

Like the air cleaner Cogsy, good job

 

[gus]

Hi Al,

Great looking Air Intake Filter. Very sporty. Makes mine antique.

 

[Cogsy]

Thanks guys. I wanted a bit of old school charm and I figured it'd be an easy piece. Turns out I was right for a change.

I'm thinking I might have to ask Santa for a better camera though, some of my pictures are so bad I don't want to post them. I promise most of my stuff looks better in the flesh.