Member postings for David Kenyon 2

Hi , I made a Congreve clock about 4 years ago , the brass has a bright polish and coated with Renaissance wax. Its kept in a glass case.

On the brass plates I keep getting a brown mark , almost like a light rust, just in a couple of small areas. I can polish it out but it always seems to come back .

Is this caused by a bit of contamination in the brass plate itself?

Well finally finished my barrels , I was going to machine a spare but got fed up with the black mess.

May regret that decision later down the line .

Have spent the last two days cleaning my mill/lathe , to be fair the most of the dust was external and

the slideways were still clean but at least I feel better now and the machines are all readjusted .

I will give it a wipe over before I start barrel no2 then probably do a strip down when I get to no4.

I like to keep my machines clean anyway so I suppose a strip down will not do any harm.

Judging by how easy It is to machine I am guessing I have soft meehanite bar.

I have been machining a 2'' round piece of cast iron into a finned barrel for an engine I am making.

Going between lathe and mill I have managed to produce a large amount of swarf and everything is covered in black dust, including me.

Not enjoying it and I have another three to do.

Will all this dust be a problem, do I need to strip down my equipment and wash everything off when I finish barrel no4.

That's great Jason thanks , I presumed the flank had a slight radius, just curious but how do know

the flanks are flat.

Looking at the timing it shows the crank moves 240 degrees for the inlet and 260 for exhaust so that would be

120 and 130 for the camshaft . On the dials for the jig it states 130 / 140 which confuses me .

Here is the whole plan , you will need to zoom in

Its for a four cylinder Gypsy engine, the plans show that the cam is built up from separate parts ie. the lobes and bearings are machined then Loctite onto the shaft.

Now I understand what a camshaft does and how it operates but I have little knowledge of making one. After some research I feel making the lobes on my mill using small flat cuts with the aid of a rotary table would be the best option for me.

So I need to come up with some figures for the machining process.

The plans show just one lobe as below

There is also a timing guide and some plans for a jig which I am not sure how its used but I assume it may be for a grinding machine

Well I tinned each half with soft solder then clamped them together and re heated.

Worked well, I managed to machine 5 bearings with little trouble although the bar did split on my third bearing

when I drilled out the centre, the drill pulled into the bronze.

I re soldered but this time put a jubilee clip around the outside until I had finished the bore .

Well thanks for the replies, certainly given me something to think about.

I was worried that the solder on the mating surfaces would compromise the final bearing size

but I see this is not the case.

I will get some solder paste and give that ago first , will let you know how it goes.

I need to saw a piece of phosphor bronze round bar in half and then solder it back together before machining to size for the split bearings.

My question is, do I put flux on the mating surfaces before clamping together or leave them clean , clamp together and then just run flux along the join.

When the piece is soldered I will need to turn the diameter down so I presume the solder will need to penetrate the join so it stays in one piece.

I did my Myford about two years ago, as already said keep the old filler coat on . Once you sand off the paint the filler is easy to sand and you can get a nice finish .

I used HMG Paints C71 enamel **LINK**

Use a good primer , I used HMG again , still looks good today.

Hi , my lathe has not got reverse so is there a way of sharpening a cutter to run in both

directions, I was thinking a single point with a rounded tip. This is so I can use a shorter

bar and reverse it to do each half as suggested in the Benz thread

I am nearing the stage of line boring my Gypsy casting, I have done all the set up on my Myford saddle and intend to first drill the hole up to 14.5mm then bore out to the correct 5/8 inch [ 15.8750mm].

My question is , what diameter round bar should I make the boring bar out of.

If I use 14mm would that be enough clearance for the cutter or do you think I should drill through 15mm and use a 15 mm bar.

The casting is approx. 7 inches long with 5 main bearings to bore through.

Thanks everyone, put an End mill through each casting this morning and it actually

cut through really easy . All holes are running parallel now.

I think I will be investing in some quality drill bits now.

Yes it is the Gypsy , the drill bit was from Screwfix [ Erbauer ] and was new.

I am using my Chester Champion mill to do the drilling , I centre drilled first then followed

with the 2mm drill bit.

I have been getting aluminium sticking to the drill so withdrawing it to clean regularly.

You can not see it on the picture but this is how I discovered the holes tapered inwards.

Thanks, I will have a go tomorrow with an End mill .

I have not used castings before and did not realise how hard it can be to

drill through even being aluminium.

Should I put a M2 mill through or open it up with an M3 .

I have been machining some main bearing caps today from a casting.

I centre drilled then put a 2mm pilot hole through each cap which will be used to spot through to the crankcase and then opened out to 4mm for the mounting bolts.

Now I have discovered the holes [ 10 of them ] have all run out of true , I suspect I used a badly ground drill bit.

I need to straighten these hole as I open them out to 4mm and was thinking of using a BS1 Centre drill as this is quite stiff and only 1/8 diameter.

What do you think

Made this Cube inside a cube piece a while ago , it was good to make as I was fairly new to the lathe and needed practice using the dials and grinding lathe tools

Thanks , I will give the MEM site a go .