Hoglet started (and running!)

[Jasonb]

I opted to drill the holes before cutting the fins. There was a small amount of wander in a couple of the holes, I mostly solved this buy enlarging the holes by 0.5mm in all but the top fin so the heads would still be corectly located. One of the holes also needed a lick with a file just to pull it over a bit more.

If I were doing it again I would start with a stub drill after the Ctr drill or cut the fins first and drill all the way with a 1/8" centre drill changing part way for a long series one, then open up to 4mm (I used M4 threads on 5/32 rod)

Jason

 

[kustomkb]

Thanks Phil, Chuck and Jason.

I've got some hollow cast bronze for my flywheels so just need to skim them inside & out

I was looking for that, I had some but wrong size, Shame to waste all that brass in the centre.

how difficult was it to drill the long, deep holes

I haven't drilled them yet. Thought about drilling before the fins like Jason suggested but I was in a turning mood.
So now I might centre drill and drill each fin. Also my parting tool deflected a bit leaving the fins slightly tapered, which complicate the drilling further.

Stock centre drilled;

Drilling;

boring; (I bored .090 oversize to allow for a .045 wall cast iron sleeve)

Dialing the QCTP back in after setting the compound over 5 deg;

fins ready to cut;

fins cut;

Tapered;

Polished ready for parting;

polishing a few tenths off the spigot end;

And now its starting to look like something! I should change the title to "hoglet half way"!

 

[kustomkb]

The drawing for this engine calls for a carb purchased from OS engines.

Does anyone have a suitable design they could share?

It would be a shame to slap on a factory made component.

Thank you very much.

 

[Jasonb]

I have a suitable OS card laying around so will us ethat to start with. May decide to build one which was in Model Engineer Mag a few months back, there is a picture of it fiotted to one of the designers engines half way down this page

Also worth a look at his latest design the "Bobcat" there is a video of the first run on the home page.

Jason

 

[kustomkb]

Thanks Jason,

That carb would be perfect! I also have an OS carb I thought about using just to get up and running but I have come this far...

I think between that nice photo and Maryak's step by steps, I should be able to come up with something.

What are you doing for your ignition? Electronic like the RcExcel?

It is very compact and I think it will run off a single Lipo cell.

Kevin.

 

[Maryak]

kustomkb,

Very nice, :bow:

Glad my ramblings are of use to others.

Best Regards
Bob

 

[kustomkb]

Thanks Bob,

It's a real help, none of us were born with these skills so it's good to share. Methinks.

Started on a drill jig I think will keep my centre drill/ drill straight and stiff.

The plan is to c'drill and drill each fin 1/8 in my drill press before opening to a 5/32 slide fit. (wishful thinking)

bore out a large dia. bottom plate to hope for squarness;

Fit bottom spigot;

And tap 1/2-13;

then machine top end that will hold drill bushing;

And ensure fit;

Drill jig without reamed holes for bushing;

have fun!

 

[kustomkb]

Clarence over at 3 little hogs has built the Hoglet with the 4 lobe cam.

He has done some very nice work.

http://www.telusplanet.net/public/celias/home.htm

 

[kustomkb]

Drilled the cylinders yesterday.

I clamped the jig to the drill press table, then aligned the bushing with a dowel pin then switched to a long centre drill.
I choked up on the drill for the first few fins and then went to full length. The fins were thin enough so that I was able to pilot drill with the centre drill the whole way;

Then switched to a .146 drill;

And finally reaming size for size to 5/32";

The holes came out very straight thanks to the long drill bushing. And were a snug sliding fit on the studs.

I often end up fighting myself because I make things unnecesarilly close fitting. After trying them out to check for alignment I will need to open them up to ensure the faces of the heads and cylinders are pulled square to one another for a good seal.

 

[cfellows]

Looks good, Kevin. Nice technique. By the way, where did you get that long center drill?

Chuck

 

[kustomkb]

Thanks Chuck.

The centre drill has been in my box for years. I also have a 6 inch. Most tooling shops should have them.

Looks like I spoke too soon. One of the holes wandered and will need to be pulled over slightly at the bottom.

It was probably the first hole which I switched to a 1/8 drill after centre drilling only the first fin. :-\

 

[kustomkb]

I made the brass valve guides today.

Started by setting a "form" tool to 14 deg. to plunge cut the taper where the intake and exhaust blows by;

and the plunge cut;

Then turned the OD for a 0.0015" press fit;

After drilling and plunging out the back end for 0.010" spring ID clearance it was ready for parting off;

Final reaming will be done after instalation.

Next up, finish the heads.

 

[itowbig]

hey can i get some of that talent so i can make prety parts like these. i really could use some.
thats coming along real nice. thank you im in school everyday.

 

[kustomkb]

Thanks alot Sid.

can i get some of that talent

"If you build it, they will come"

A little more today.

Drilled the intake and exhaust holes;

Then drilled and reamed for 1/4 dowels to set the fixture over 21deg.

I reamed a scrap of AL. to ensure the pins pressed in square;

Then replaced the soft jaw and clamped the fixture in place, ready to mill the angled ports;

Ciao for now!

 

[Maryak]

Kevin,

Nice work. :bow: :bow: ETF ???

Best Regards
Bob

 

[kustomkb]

Thanks again Bob.

ETF

??? ???

Heads set to 21 deg. for intake;

Intake bored;

Set over for spark plug bore;

Bore complete;

ready for outside contour;

Roughed;

finished;

cooling fins cut;

Test fit of heads;

Also radiussed the tips of the push rods;

And used a crappy tire die nut : to threads 4-40

which cut okay

Then faced to length and centre drilled the push rods;

And turned down between centres, (had no 3/16 AL)

Have a good day!

 

[PhillyVa]

Hi Kevin,

Wow that's look'n real good...keep up the great :bow: work :bow:

Can't weit to hear it run and that's no th_bs

Have a great long week end.

Regards

Philly

 

[Maryak]

Kevin,

Beautiful job. :bow: :bow:

Best Regards
Bob

 

[kustomkb]

Thanks alot fella's.

This weekend I hope to get the valves and lifters finished and rough out the cam.

Looks like we'll have nice weather for the long weekend finally, eh Phil?

KB

 

[PhillyVa]

Yea nice for the long weekend and a :-* HONEY :-* DO LIST a yard long. :shrug: Maybe I'll have to go on an building materials run and pop by.

Regards

Philly