Valve Grinding Equipment

[49-1183904562]

WPH,

How is the collet setting(Clamping) does your insert have the taper?

Rick

[WPH]

EDIT:

Insert has the same angle as collet, 16 degrees total (accuracy as per the lathe degree scale, didn't have anything more accurate way to do it).

I'd say the mainshaft has exactly the same kind on taper as per B&d grinders, at least it looks a lot like the one I have at work. Kind of a four piece "spring" collet, 8-11mm range. ER25 has a different angle on the "nose", it's not as steep. I just finished the trial assembly of the new mainshaft components and was surprised how small the run-out was. I did the centering with a dial indicator and the lowest reading was 0.03mm, average being 0.05-0.07mm. I didn't re-bush the shaft holder but I used a thin, concave washer which pre-loads the thrust setting pretty nicely. I think that re-bushing could possibly half the current run-out (which can also be quite big if you don't set the valve properly). I'll add couple of pictures as soon as I upload them to Photobucket.

[WPH]

Run-out was measured on the edge of 48mm SS valve with the setup below:

[106-1194218389]

So right now you gauge reads .005" run out correct? If this is so then it really is only out .0025" offset and this makes it act like a crank shaft stroke and shows .005".

John

[WPH]

0.05mm, not inches. Quite a difference, and this was the total measured value between high/low.

[106-1194218389]

Oh yeah much different. That is only .0019" run out and only .00098 off set. I'd run it Sorry for "assume" ing so I guess I made the proverbial donkey out of myself :;):

Good Work!
John

[49-1183904562]

WPH,

Is it repeatable or do you need to indicte each valve then Grind???

Rick

BTW, Nice first try, you are giving me hope

[WPH]

Unfortunately, repeatability is the issue. Angle at nose of the mainshaft is steeper than ER collet's. Collet has only a very narrow margin which centers it to chuck face. It kind of "bites" to this surface and the setup goes crooked. I'm thinking of another insert between the ER collet and the chuck, I'll probably get it turned today. Does anyone know the side angle inside the chuck on B&D grinders?

[WPH]

I managed to measure the angle inside the chuck, its 60deg total, the same as in ER collets. So thats for the theory on narrow margin. I thought this over once more and took a better look inside the chuck. The insert is supported in two points, at the end and in the middle. I have to measure the inner dia of the chuck more precisely and maybe to turn a new insert with even smaller tolerance.

[Moriniman]

[color=#000000]I've just found myself a Wolf brand valve refacer on ebay UK.





It cost me just GB

[larrycavan]

[49-1183904562]

Larry,

Do you have any interest in a J Head Bridgeport virtical mill? I am just finising rebuilding (bearings belts etc) the head on one that i plan on selling. I would offer a reduced price to forum members.

Rick

[106-1194218389]

[49-1183904562]

John,

Not sure if my motorcycle would pull the trailer :p

But if anyone is in driving distance to Maryland (Frederick) I would work with you.

Rick

[bruce]

I'm within driving distance :;):