Chas Parker 272 challenges

[btrnuthatch]

This is a follow-up to my recent thread re. my new vise addiction that included a Chas Parker 272. I don't know how much more I'll put into this thing vs. selling for parts. I am going to use the collar to create a mold to cast more in bronze. I think I'm missing a washer that sits behind the collar as there is a 1 1/2 turn slop when moving the jaw in and out.

The base is different from Catalyze's beautiful 272 restoration (a more recent version?) and those small set-screw pieces in the handle are missing. I'll also have to fabricate a handle for the swivel base tightening bolt.

I thought the original dynamic jaw was missing in the brazing (?) job done. But once I cleaned it up, it's actually still there though ensconced in the weld. Can't imagine what happened to necessitate that repair.

I'm still contemplating what to do about the swivel jaw piece that's broken at the bottom (including Outlaw's fine suggestions). I think it will work fine without fixing; it will simple lift out because the pin won't hold it in since the pin's has nothing to groove into.

Better as parts or worth salvaging with repairs?

 

[SJK2]

Let us all know if you cast parts, myself i need a collar.....

 

[btrnuthatch]

I've started the process today making 1/2 of the rubber mold of the 272 collar. I'll do the 2nd half next week. Then I'll use the mold to make waxes, one exactly like the 272 version and then I'll adapt the wax to make the 974 1/2 version. Next, on to the bronze casting work. It'll be a month or more before I get them done -- I'm going to do several copies. I'll post when that time comes.

 

[Packard V8]

Yes, as a project, it looks like fun.

No, as an economical fix for a hard-working vise, not so much.

Maybe, post updates as it goes along.

jack vines

 

[btrnuthatch]

Collar casting update.

I've made the mold from the 272 original. The mold is made in 2 parts representing the front and the back of the collar. After pouring melted casting wax into the mold and allowing the wax to solidify, I separate the mold to remove the wax impression. From the mold I've made a few wax replicas that will be used for casting which you can see in the bowl of water (to keep them cool).

 

[Provincial]

Does the mold material compensate for shrinkage of the wax and the part when cast? With such a small part, it shouldn't be much. I remember seeing a patternmaker's rule, which had the shrinkage built in - you had to be careful not to pick up that rule to measure or lay out anything normal, since it was long by 1/10" in a foot!

 

[Catalyze]

btr - Thanks for the very energetic approach to solving a common Parker problem!!
Also, with your photos and commentary, I will learn about how parts are cast. Keep up the good photos and efforts. I will keep checking on this thread.
Craig

 

[btrnuthatch]

I made 15 wax copies of the 272 collar and modified a few for the 974 1/2. The image is how the waxes are "gated" for the molten bronze pour (don't know why it's sideways). I forgot to take a picture today when I finished the gating which included attaching a pour cup. Then a cylindrical cage of chicken wire and roofing paper is made to receive an investment mixture of plaster and sand. That plaster cylinder will go into a kiln whereby all the wax will be burned out leaving a void of the gated collars -- the process is called "lost wax." The bronze will be poured mid Sept. The 2nd image is a previous aluminum pour.

 

[btrnuthatch]

Poured the bronze today. I quickly did a cursory clean-up on one to show how it looks. I'll need to do some additional detail work and tuneup do get a tighter fit. Anyway, my initial reaction is that they'll be serviceable.

A couple images are for comparing and contrasting against the original. And I included an image of the castings after being busted out of the plaster mold and a few of them after I cut them off the gates.

As previously noted, the Parker 272 collars are different from the 974 1/2 collar which I modified in the wax. I'll see if that adaption works soon.

 

[btrnuthatch]

Did more work today to try to better fit the 272 collar as well as fit the 974 1/2 adaption. Both are doing the job. I did recess the 974 1/2 version a bit since it is thicker. I included a side-by-side to show the differences.

I'll try to take out some of the blemishes but not to the nth degree because they're not that noticeable when installed.

That'll be it for this exploration. If anybody needs/wants one, send me a PM. I have a few extra of both versions.

 

[SJK2]

Received my collar tdy from Byron, great piece of work and shipping...........

 

[mcoz]

I am considering the acquisition of a 206. It is missing the front collar. I wonder if these will fit the bill?

 

[retDAC]

Notice the age of this thread. You need to PM the OP.

 

[mcoz]

Did that too. Thanks.

 

[jsmgpworker]

Do you have any of these collars left for sale; need one bad!

 

[btrnuthatch]

Yes, I have a few more but they are only semi-finished. They'll need more work. PM me if you are interested and I can send images to give you a better feel for what you'd have to do.