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[Twism_23]

I emailed to someone about milling my heads today and in his reply he wrote something I had never heard of so I wanted to ask you guys on here about it. When I asked the cost, he said, "normally it's $65.00 a head but to cut the step as well it will be $80.00." I don't know what he meant by "the step". I replied asking the question but they are closed so I thought I'd ask on here.
Thx

[TorqueInc]

Must be Coffee

might be referencing spin dropping the head....leaving the combustion chamber part of the head lower than the rest of the mating surface to increase compression without cutting the cylinders shorter or using pistons with a taller compression height.

[prodrag1320]

your not using cylinders with a fire ring? he could be talking about that.if its just a regular sock head/cylinder,i have no idea what he`s thinking about

[Twism_23]

Thanks

[HILLSIDECYCLE.COM]

We've established "drop-spin" cylinder head machining when/where warranted.
You can set the quench/squish your looking for, regardless of the piston being below deck, or cylinder head gasket thickness.
Piece-o-cake.............
Scott

[rbabos]

Yup. Spin drop developed by Coffey back in the shovelhead days. Better options these days. Heads hang around a lot longer then cyls do , so why not modify the cyl instead of the head for decking?
Ron

[TorqueInc]

 Probably would not hurt to square up the cylinders anyhow,probably should be done on a between centers mandrel instead of being stuck against a 3 or 4 jaw,way less runout. 

[timo482]

lathe chucks are within a few thou, 5c collets are within a few tenths - if they are clean. a mandrel can hold a tenth or two if the bearings are good on the live center and the dead center is true.

of course it helps to have a large oversize heavy lathe with good bearings..  hardinge or zubal or something like that.

to

[HILLSIDECYCLE.COM]

lathe chucks are within a few thou, 5c collets are within a few tenths - if they are clean. a mandrel can hold a tenth or two if the bearings are good on the live center and the dead center is true.

of course it helps to have a large oversize heavy lathe with good bearings..  hardinge or zubal or something like that.

to

We manufactured custom 6061-T6 aluminum soft-jaws to gently hold the radius of the ID of the cylinder, many, many years ago.
We then do not arbitrarily suspect that the cylinder is running true, as it is then checked with a Starrett Last Word universal test indicator, and adjusted to run true, if need be.
Then, at that point a bull-nose center is brought to contact/support the spigot, and the back face of the precision center is also indicated to run true, and then the tailstock is locked, and then gentle cuts are then made to establish the desired overall cylinder length.
This method is very rugged, and very accurate.
The mention of the 3-4 jaw comment is a totally ludicrous remark from someone not aware of simple, basic, machining processes, that any entry-level apprentice, would/should be overly aware of.
Boot, in mouth, once again.
Scott

[timo482]

 I recently made some steam valves that were spec'd four digits and had to sixe on the zubal, tool a day to make the fixture with a soft 5c face collet, 32 parts within five tenths... Exhausting work having to hold my breath moving the dials fractions of thousandths. Really should put a dro on the compound .

[HILLSIDECYCLE.COM]

I recently made some steam valves that were spec'd four digits and had to sixe on the zubal, tool a day to make the fixture with a soft 5c face collet, 32 parts within five tenths... Exhausting work having to hold my breath moving the dials fractions of thousandths. Really should put a dro on the compound .

Used to hold some mighty tight tolerances myself, when employed by various tool shops.
You could set-up a .0001" indicator such as a Federal, on that compound next time you encounter that?
The 10', .060" thick wall, Reynolds seamless aluminum tubing drive shafts for the AH-64 Apache attack helicopters had .0005" bores on each end, and had to run within .001" of each other.
Think about that one for a miniute...........no joy, but we made 'em.
Scott

[TorqueInc]

We manufactured custom 6061-T6 aluminum soft-jaws to gently hold the radius of the ID of the cylinder, many, many years ago.
We then do not arbitrarily suspect that the cylinder is running true, as it is then checked with a Starrett Last Word universal test indicator, and adjusted to run true, if need be.
Then, at that point a bull-nose center is brought to contact/support the spigot, and the back face of the precision center is also indicated to run true, and then the tailstock is locked, and then gentle cuts are then made to establish the desired overall cylinder length.
This method is very rugged, and very accurate.
The mention of the 3-4 jaw comment is a totally ludicrous remark from someone not aware of simple, basic, machining processes, that any entry-level apprentice, would/should be overly aware of.
Boot, in mouth, once again.
Scott

  If I wanted to spend all day setting up cylinders....that would be fine

  With a mandrel you can cut both ends off the same setup....much quicker and more accurate.

  Not sure how having the right tool for the job makes you right or wrong but.....no beaver tooth marks in my cylinders 

[HILLSIDECYCLE.COM]

  If I wanted to spend all day setting up cylinders....that would be fine

  With a mandrel you can cut both ends off the same setup....much quicker and more accurate.

  Not sure how having the right tool for the job makes you right or wrong but.....no beaver tooth marks in my cylinders 

 Too funny.............

[smiley1049]

Try using some of that knowledge Then

[willyB]

Oh no, the vendor on vendor sarcasm continues