Swifty's build of Howell V4

[gus]

Everything x 2 or 4 or 8. There are so many mini parts to make. The Howell Engines are quite demanding on time and skill and quality and finishing.You want to make good parts. When there is one of the four is not so good looking, you will want to redo that part too.Eight Tappet Valves to turn is no joke.The stem is not thick and easily damaged.

I admire your determination to turn out a good engine.

 

[Swifty]

Next part to tackle is the Valve Lifter Bushings, 8 required plus 2 spare. The material is bronze, and they have an offset head for clamping purposes. First problem was that I did not have the right dia. bronze to turn them in the 3 jaw chuck, I had a slightly smaller bar, so by using the 4 jaw chuck and offsetting the bar I was able to turn all the parts.




Next job was to mill the heads to the correct shape, after a bit of thought, I made up a quick fixture that I clamped down on my rotary table. This worked out well, and they were soon all done.




Next, the parts were held in a collet chuck in the lathe, and the centre hole drilled and reamed. The only thing left to do now was drill and counterbore the hold down holes, each part has half a hole in them. Another quick fixture was used, held in the milling vice, the pressure closed the fixture and held 2 parts at a time.



Finished parts.



Paul.

 

[Swifty]

Just for a change, and to get away from multiple parts, I ground up the form tool that is used for the pulley grooves, and then turned the crankshaft pulley. There are 3 other pulleys that I can use the form tool for later. Also in the picture is a cap that will secure he pulley on the shaft.



Paul.

 

[gus]

One has got to love or hate the Howell engines for its many intricate parts.
Paul. Great job.

 

[Swifty]

Hi Gus, there's a lot more parts yet, I tend to look at the drawings and think "too hard", and go onto something else. But at some stage I have to face these hard parts. I have to order some cast iron for the cylinder liners, as usual, I only have enough material for 2.

Paul.

 

[gus]

I thought it was best to tackle the easy meat----------the small misc. parts and I was wrong. When there are 4 pcs, they just got to look same when 1 pce went way out, being a sore loser,I just had to make another pce. Ha Ha. Will be back on Friday 22 and work one last small piece---------the exhaust manifolds and the bearing housings,crankshaft etc folllows.

Burnt-Out battery now charging nicely.Ha Ha. Nellie having a great time window shopping.

Take care.

 

[Swifty]

The past 2 days, I've managed to do a few more parts, I turned up the cam blanks, plus 1 spare. You might look at the picture and wonder how I'm going to hold them for profile milling, I have an idea for a fixture that I hope will make it easy for me. I also have 8 + 1 valve lifters, and the valve push rods, the rods just need a thread on the end, just waiting on the arrival of a 3-48 die.



I also loctited the valve cages in the heads and drilled the inlet and exhaust holes. For those that have made this engine before, you may notice that I haven't machined the exhaust holes for a round gasket, I intend to have a full profile gasket in this area.



Paul.

 

[Cogsy]

Another selection of nice looking parts, especially those impressive heads.

What loctite did you use for the valve cages and are they a press/shrink fit or just snug? I've been mulling over my options for retaining my valve cages and haven't made a decision yet.

 

[Swifty]

Hi Al, I used loctite 601 retaining compound. It's a bottle that I had left over from work, but it's still fine, we used it for retaining pins in holes. I didn't realise that here were so many grades of loctite until I did a Google search, I have a couple of bottles of thread locking and a couple of retaining.

The guides were a light tap fit in the holes.


Paul.

 

[gus]

OuterHeads now growing parts. Thats good. Still in Penang with Nellie doing more than her fair share of shopping.Guess if I am not too tired,I'll start working on two small parts --------exhaust manifolds. 3/4'' x 1/2 x 1/2 .Gus is no good with small parts. Will make 4 to get 2.

 

[Swifty]

Hi Gus, glad you are having a great time with Nellie, on Facebook you seem to be eating all the time

I'm making spare parts in case I drop one and can't find it.

Paul.

 

[michael-au]

Nice collection of parts you have there Swifty, coming along nicely

 

[gus]

Hi Gus, glad you are having a great time with Nellie, on Facebook you seem to be eating all the time

I'm making spare parts in case I drop one and can't find it.

Paul.

Good Idea. Some of the parts are so small,you lose it when parting off.
Some parts gets badly dented when dropped. The rocker arm pins too.Some gets lost or misplaced.Ha ha.

Penang food hawker food is quite unique. Its not Chinese or Malay. Its mixed Chinese,Thai,Malay and Indian. Very unique and authentic. Somehow back in Singapore,we cannot cook as good or near to authentic.

No worry,we did not eat like gluttons. Nellie and Gus would share one bowl of whatever desserts of the streets. Heading home tomorrow and go on diet to trim back.Ha ha.

Bought a AC/DC converter for the Power Mill Table Feed to replace the 12 v battery. Very cost effective. Very favourable currency conversion.OneS$ =2.7 Malaysian $.

 

[Swifty]

Nice collection of parts you have there Swifty, coming along nicely

Hi Michael, I have the mill all set up to go for machining the cams, no more work today though. Tomorrow I have the grandson all day to look after, so it looks like Saturday before I can try out my method of cam cutting. I will post lots of pictures.

Paul

 

[Swifty]

I machined one end of the cams tonight, took me a casual hour to machine 5 (one spare), its the intake end. I made a fixture that bolts to my rotary table, fixture was in 2 parts, I bored the location hole all the way through and put a plate underneath, this way I had a nice square corner in the bottom of the hole, when trying to bore a blind hole, it's always a pain to get a sharp corner. The plate was centralised on the rotary table and I tapped a 3/16"hole in the bottom plate to allow me to fasten the cam blanks. Before I did any more, I set the boring head to the correct radius for the cam flank, I used a scrap piece of aluminium and turned the large dia, to suit the size required, and a step the same size as the cam blanks to locate in the fixture. I adjusted the boring head until the tool just scratched the setting piece.



The first cam blank was then set up, I had previously worked out on CAD where the flank rad centre was, so the X axis was set to the correct dimension, and I fed in on the Y axis until the correct reading was showing on the readout.




I then moved the other way and cut the second flank.



All I had to do now was swap over to a cutter and mill the excess away between the flanks.



For the next one, I just left the cutter in the spindle and cut the excess first, then put the boring head back and cut the flanks, this saved a bit of double handling of cutter and boring head. When I did the CAD drawing, I also drew in the correct angle to blend in the flank. I started with the rotary table set on zero degrees, so just had to rotate in either direction to the correct angle. Here's one end straight off the mill.



I have an idea how I'm going to locate for the other end, 2 of the cams are "left hand"and 2 are "right hand", so I have to be able to rotate the fixture to suit, and also set the first profile in the correct position.

Paul.

 

[gus]

Your cam looks good.

Start work again. The exhaust manifold took 2 hours in the morning and another 1 1/2 in the afternoon with one minor goof.
No extra weight gain and possibly due to the sightseeing and walking.

 

[michael-au]

Nice job on the cams Swifty 👍

 

[Swifty]

I've made a new fixture to locate the inlet profile and machine the exhaust profile. The first one I did, I took a bit too much off the flanks, so there goes my spare. After a readjustment, the next one came out fine. I will post the pictures tomorrow.

Paul.

 

[Swifty]

Here is my modified jig to locate the end that has already been machined. I started off with a hole the same diameter as on the cam, but then I made a sliding location plate that locates the high point on the inlet cam and pushes it against the location dia.




The end that I was machining in this set up is the exhaust cam profile, I had to be careful as 2 are LH and 2 are RH. Just a matter of rotating the rotary table to the correct degrees. Here are the 4 cams, just need blending of the top radius and some polishing, then heat treatment.



Paul.

 

[Swifty]

Just a bit of an update, I made the spacers that go between the rocker arms, as well as the bearings that are inserted in to the pivot holes in the rocker arms. The drawing calls up delrin for these parts, I tried using some plastic that I had, but was not happy with the results, so made the parts out of brass instead. I have started to paint the grooves in the heads and the side pockets of the rocker holders, first off was a coat of etch paint prior to the top coat later.



Paul.