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This is the cylinder head frame that I worked on today. All I need to do is tap the thread for the NGK spark plug and bore the recess for it. I won't do that until I receive the plug so I can double check the dimensions and thread.

I have ordered some drill rod for the cam shaft. I am also going down to the Viton Dealer tomorrow and pick up a few Viton O-rings.

You will notice on the photo that one of the holes is slightly damaged at the start of the hole (this was the last hole to drill). I was being very careful, however, I had inadvertently knocked the adjustment wheel on the milling machine table. To make sure that it was going to be in the correct position in relation to the other holes, I reversed the piece and drilled it from the other side. This took me about 45 minutes to set up so that it was going to be in the right position. Anyway, all worked out ok.

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Brian,
I have been reading to posts on the Webster and I notice that you reamed the bore for the cylinder with a 7/8 chucking reamer. I was going to do it on the lathe with a boring tool. Now, I am not sure what is the best method of getting a good finish and a straight bore. Can you give me some advice on why you went that way?
John
 
Simister--When I built the Webster I was very new to this machining game. I had read many posts about the poor finish left by internal boring, the problem with internal tapers induced by boring, and a whole load of possible "fails" caused by boring the cylinder. I thought, "What the heck"---If I buy a reamer, the finish will always be consistent, assuming the same rpm and material and lubricant used, there should be absolutely no induced taper, I won't have to worry about tool flex on long bores---And--If I build a dozen more engines in future (which I pretty well have) the size and finish of my reamed bores is never going to change. I have taken out all of the variables. Now 500 people will immediately jump on me and tell me that boring is better, but I know what worked well and continues to work well for me. I do have a complete set of boring tools now, and a boring head for my mill, but I still use reamers when making cylinder bores.---Brian.
 
Hi John
Your Webster is looking good. Personally I have to agree with Brian. I have a decent set of boring bars and I do use them a lot but to be honest if I’ve got a reamer the right size I’ll use it.
I’ll be following along for the ride . . .
 
Bob & Brian,

Thanks for your input.

I cannot purchase a 7/8 chucking reamer here in Australia. I have contacted a number of suppliers and they claim they are not available. Can you suggest a company in the US that I can contact where these would be available. I have a US shipping address so it can be on forwarded to to me.

Also, I would require it with a MT2 taper. Should I get a right hand or left hand cut?

Thanks guys.
 
I cannot purchase a 7/8 chucking reamer here in Australia. I have contacted a number of suppliers and they claim they are not available. Can you suggest a company in the US that I can contact where these would be available. I have a US shipping address so it can be on forwarded to to me.

Also, I would require it with a MT2 taper. Should I get a right hand or left hand cut?

Thanks guys.

It will be referred to as being a 7/8" taper shank reamer, chucking reamers always have a straight shank. Should be no problem getting one in Australia, even try Ebay.

Edit. Quite a few straight shank reamers available, but the shank size is also 7/8", look for a taper shank one.http://www.ebay.com.au/itm/size-7-8...66?pt=LH_DefaultDomain_15&hash=item2c769cb692

Paul.
 
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On those larger reamers, the working end is hardened. The shank is soft and can be turned down with a carbide to fit into a 1/2" or 5/8" tailstock chuck. You can buy through Travers Tool co. inc--they ship internationally.
 
Spark plug arrived today. "Wow - it is small - very cute" . I checked the threads and finished the cylinder frame completely. Now on to the next piece.

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Does anyone know where I can purchase the intake and exhaust valve springs?

I have tried a few of the spring dealers here, but whilst they have plenty of compression springs they don't have the specs required for the webster.

Is it that important or could I use a stock compression spring of similar coils and wire?
 
You can use any suitable spring, the specs are just a guide. I bought a cheap spring assortment box from the hardware store for about $15 with a mix of compression and tension springs and I've used various sizes on my I.C. engines. I just dig through and try different ones til I get one that works.
 
Hi John,

No worry.Just like Cogsy,my Webster Engine valve springs came from same box. Engine ran very well.
 
I bought mine from CenturySpring. They have a $40 minimum order, so I bought springs for the Webster, the Farm Boy (future build), and a few standard sizes I'll find a use for someday to flesh out the order.
 
Thanks Guys. I have a box of assorted springs so I will try those. I did have a look at the Century Spring website and thought that they would have to custom make them.

John
 
John--In Canada we have two major suppliers of industrial fasteners, Brafasco and Fastenall. They sell nuts, bolts, etcetera, and they both sell a wide assortment of compression springs. I can't remember the name right now, but there is a spring company (probably out of USA) that has a fairly large metal box with about 50 drawers in it full of various little springs in all of these stores. The springs are sold individually for about $2 or $3 each, and are perfect for engines like the Webster. If you have an industrial fastener supplier anywhere near you, that would be the place to look. I have had to wind my own tension springs for governors on hit and miss engines to get exactly what I needed, but never for a valve spring.---Brian
 
OK, Thanks Brian,

We do have some industrial fastener suppliers close by. I will call in as it would be handy to know what is available off the shelf.

I had been calling spring manufacturers and they basically manufacture to order in large quantities.

I have a box of assorted springs here, so that will probably get me started.
 
''Spring Design and Manufacture'' by Tubal Cain is highly recommended for wannabe DIY Spring Makers. Made some with piano wires bought from AeroModel Hobby Shops. Will take a bit of practice to make springs to satisfaction.

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