How to align Kurt clone Jaws

I need to align new jaws for my 6" Kurt clone. Jaw's lower end is not sitting against ways. Bottom of jaws is about 1/8 from ways. Jaw top and bottom are not quite parallel. Is there any procedure to make jaw's tops parallel to the table?

Thanks.

Reply to
Alex
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Reply to
Alex

If the jaws truly aren't parallel, top to bottom, they should be ground on a surface grinder until they are. You'd have to measure the jaws to determine which would be the better starting point, then grind one side of each jaw, then gang them and grind the second side with both jaws as a unit. Shimming could be required to correct any errors. If you don't understand the process, you'd be wise to recruit someone that is familiar with surface grinding.

I'm having a hard time coming to terms with the idea that you can't get the jaws within 1/8" of the ways of the vise. Do you have the proper jaws?

Here's what Id' do, assuming you had the proper jaws.

There's usually not enough slop to get off as far as you are, but I'd put the vise on the mill table, snug up the fixed jaw, then clamp it to the vise using a strap clamp from the mill table, clamping the top, so it bears down on the vise base. Just get it snug, so things can move under screw pressure. That should get it as near parallel as possible. Once you've snugged up the clamp, tighten the screws. Do it in a couple of sessions, tightening things a bit more for the second repetition, to insure that the jaw really is down. If, afterwards, the top of the jaw is not parallel with the table, you have some serious issues that need to be resolved. You should start by determining if the vise slide is parallel and perpendicular to the base.

Assuming the fixed jaw turns out well, follow up with a piece clamped in the vise, something that's parallel, and repeat the process you just undertook, only with the moveable jaw.

Harold

Reply to
Harold and Susan Vordos

Harold,

these jaws are for standard 6" Kurt. I have a Kurt clone. It has smaller screws, they placed wider that in Kurt and height of jaws is also different. The jaws are hardened. I don't have a surface grinder. Is there any way to grind hardened steel on my mill?

Thanks, Alex

Harold and Susan Vordos wrote:

Reply to
Alex

Are you sure your mill is tramed in properly?

Reply to
Dave Lyon

Greetings Alex, From your description it sounds like you have the jaws upside down. The bolt holes in the jaws are not on the centerline. This is so the jaws can be a little higher when needed. If you are clamping a really wide piece you can turn the jaws upside down and mount them on the backside of the fixed and movable vise jaws. This way a piece 12 inches wide can be held in the vise. Anyway, in your situation just turn the jaws over and they will sit down against the vise ways. Cheers, Eric

Reply to
Eric R Snow

Since the Kurt jaws don't fit the vise, either modify the vise to fit the jaws, or make new jaws that fit the vise.

You can move and enlarge the jaw mounting holes in the vise. How difficult this will be depends on whether you need to plug the existing holes to get a complete thread in the new location.

Aluminum jaws are adequate, and sometimes an advantage, for most purposes and are easily retrued when they get dinged up.

I have a Kurt clone with odd jaws like yours. It is the same height as a Kurt, so I keep it around for holding long pieces with two vises on the mill table.

Ned Simmons

Reply to
Ned Simmons

--Howzabout switching to soft jaws, then flycutting the tops? Soft jaws are about all I ever use these days..

Reply to
steamer

Yes, you can "surface grind" using a cup wheel that is hand dressed, but it's a poor compromise for a surface grinder. The biggest problem you have is that you can't get fast enough motion from the mill table to avoid burning. That's the reason for the hand dressing of the wheel, to minimize wheel contact. The cup wheel should be dressed with a slight angle inward, so the outer lip touches, and only for a small area.

If you decide to attempt this process, make sure the wheel you mount is run near the recommended speed, and mask your entire mill, even places where you thing grit won't accumulate. It will take you as much time to mask the machine as it does to grind the jaws. Depth of cut will be very shallow---a thou at a time at the most, and you'll have to be diligent about dressing the wheel------you'll notice that it starts burning quickly as the grains of the wheel dull. Dressing into a vacuum hose will help minimize the mess you'll make.

I think if I was you I'd pay special attention to the advice Ned provided.

Harold

Reply to
Harold and Susan Vordos

---but it LOOKED just like a vise.

This is so funny, it reminds me of an expression my friend uses all the time--

"If you want economy, you've got to pay for it."

Reply to
Jon

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