Kurt D688 vise tear down and rebuild

[Asm109]

The rubber o rings under the moving jaw help with the positive pull down feature of the vise.
The act as a spring to hold the jaw up within the small clearance of the moving jaw.
When you tighten the screw, the pull down features force the clamp to move down slightly bringing your part down snug onto parallels or the bottom of the vise.

 

[Mill Lee farm]

Thanks @Asm109 !
I did learn about the O-ring purpose from browsing the forum and watching Joe Pie’s video. But adding it to this thread is a good idea. I’m hoping this thread might help other’s like me out.

I’m sure rebuilding a Kurt is a pretty simple and common thing for the pro’s and old hands on here, but I found a lack of available info. Maybe this thread can fill in some of the gaps?

The interweb seems to be at odds on the usefulness of the O-rings. Some feel the ~.002” lift will just let chips and junk under the jaw and wear the ways… Others think it helps in clamping.

That’s probably a discussion better addressed in another thread though?

 

[Mill Lee farm]

Came home to a care package on my porch

 

[finsruskw]

I went down that road w/my D675 a few years back.
And doing it again with another.
The base is at the shop getting the ways cleaned up as I type this.
What are you going to use for paint?
Outlandish blue??!

 

[Eddyde]

My D688 vise came with the two lift o-rings when I bought it new in 2015 but didn't install them at the time. I recently gave the vise an inspection and cleaning, I thought I'd try the o-rings but I did not see the circular recesses for them. Baffled, I reached out to Kurt, who told me they discontinued making them that way because of the chip fouling issue.

 

[Mill Lee farm]

Baffled, I reached out to Kurt, who told me they discontinued making them that way because of the chip fouling issue.

Now that is interesting hearing it directly from Kurt.
That does seem to be the concern stated by many.

@finsruskw Not sure about painting. the oiriginal paint isn't 'too' bad....
But I think I still have some Ford tractor blue brush on. Maybe I'll try touching up some of the bare spots etc?

 

[Eddyde]

Here's the email I received from Kurt:

Hi Ed,

Thank you for reaching out about the following:
I purchased a D688 from you in September of 2015, the vise came with 2 o-rings and instructions on how to install them under the moving jaw. However, I did not install them at that time. I have lightly used the vise since without any issues, It works flawlessly. I recently disassembled the vice for cleaning and thought I'd finally install the o-rings and give them a try, however I could not see any recess or place they should go! I then searched the web and found a couple of videos clearly showing two ring shaped recesses on the underside of the movable jaw. They are not present on my vise. Apparently, they were skipped in production and overlooked in QC? Can you please remedy this?

When we first designed the D688 vise, we had this O-ring design incorporated into the movable jaw. We eventually discontinued this design in the movable jaw because it caused many problems with metal chips getting stuck under the jaw.

We found that it was a bad design, so we discontinued it.

Let me know if you have any questions.

Thank you,

Caden Hill
Technical Support Engineer
Kurt Manufacturing Company
9445 East River Road NW
Minneapolis, MN 55433
chill@kurt.com
Phone: 763-572-4425
www.kurtworkholding.com

 

[finsruskw]

Great info to put away in the ol' memory bank or, in my case, what's left of it!

 

[Mill Lee farm]

Been checking around for a shop that can regrind the vise. No one does it around here? At least no one that I talked to or that responded to me. A number of shops haven’t responded to emails and voicemails.

One of the local shops said he had a good grinder guy in York but that shop closed down because he got tired of searching for employees… no one wanted to work I guess? He told me that if I find someone to let HIM know! lol

Anyway decided to slap it back together with new parts and check it out.

First I needed to clean up the badly worn section of the screw. Badly groved and scored.
(I forgot to take before pics)

After a little time in the little Atlas 6” lathe with a file. (Had to take the tailstock off! Also, I left Mom’s motivational poster from the 80’s up for a little flair! Ha!)





Then I worked it with a coarse stone followed by a fine stone. Much better! Feels smooth. Still grooved but the contact surface is now smooth:




Next was the vise body… same thing. Badly scored and grooved.



I used a small cylinder hone in a drill and worked it for a while until smooth:



I put it all together with a touch of oil and it is SO much smoother!!!

Now I just need to find someone to surface grind it and it’ll be like new!