Re: Metal fatigue or Zinc Pest?

Yes.? "Zinc Pest" as mentioned.? Caused by impurities in the alloy.

It is my sense that this is very rare on Unimat parts.? But one bad batch of the alloy can produce a bac batch of parts that will fail, often taking many decades to do so..

Model Railroaders have seen a lot of this with parts made from zinc alloys with questionable quality control.? Here are photos of a Varny HO scale diesel switcher truck from a kit that was stored about a half century and never unwrapped.? The photos below show what I found.? Similar to your situation.? But it is not the only failure mode.? Sometimes it just starts crumbling to dust.? Sometimes a part may drastically warp.? There really is no way to repair it, and it will continue to get worse over time.

Charles E. "Chuck" Kinzer

On Tuesday, July 9, 2024 at 08:09:09 PM PDT, Brad Barton via groups.io <xbartx@...> wrote:

I have a DB200 lathe and the Vertical Column Headstock Adapter is in just the worst shape.

None of the other casting on the lathe shown any of these signs.

Anyone care to guess what caused this?

?

Re: Metal fatigue or Zinc Pest?

#63312

Zinc pest, for sure.?

Paul

Show quoted text

On Tue, Jul 9, 2024, 9:09?PM Brad Barton via <xbartx=[email protected]> wrote:

I have a DB200 lathe and the Vertical Column Headstock Adapter is in just the worst shape.

None of the other casting on the lathe shown any of these signs.

Anyone care to guess what caused this?

?

Metal fatigue or Zinc Pest?

#63311

I have a DB200 lathe and the Vertical Column Headstock Adapter is in just the worst shape.

None of the other casting on the lathe shown any of these signs.

Anyone care to guess what caused this?

?

Re: DB/SL Belt Sizes?

#63310

I use 4 mm polyurethane belts, which is about 5/32"
To measure the length, I use an appropriate cord and wrap it around the pulleys. ?I subtract 10% of the length from the measurement determined in this way. This results in sufficient tension and does not overload the bearings.
The belts are welded with a hot blade.

Re: What are these?

#63309

Could be that cylindrical gauges match bearing sizes? They could be used to check machined bearing seats for prescribed fit.
--
NapierDeltic

Re: Unimat 3 Vertical Milling Attachment; Pinion

#63308

Thanks Richard. With your numbers I moved forward with a bit of polishing on both the hole and the shaft. All is now fitting quite nicely.

Cheers,
Timothy Jump

Re: What are these?

#63307

?Carl, you may be correct.

Perhaps a little more background might help us. My step dad first took me to where he worked in 1955. It was the tool room for a large plant. I was not allowed to wander about and stood at the large open doorway and looked in. All a 12 year old boy saw were lots of very large and black machines.? The owner of the plant was a German immigrate coming here in the early 30's. I do remember my step dad telling my mother that most of the machines in the plant were German made, most likely before WWII. He also said that everything was made "in house". Perhaps because parts for these machines weren't? available.

I am sure they made gears. Perhaps this was the gauge he used to measure the width of various gears before they were made. This seems plausible.

There are still two other mysteries here. What could the tiny gauge be used for? The two gauges with a 40 degree pitch don't seem standard.

I know none of this has much to do with unimats. Just a puzzle I tried to solve for a long time.

Larry

?

Re: What are these?

#63306

开云体育

Hi Larry:

I think it is a thickness gage, the difference from one notch to the next is about 0.6 mm. It might have been used for sorting sheet metal?? The notches are not deep enough to check round stock, except across the end??

Carl.

On 7/6/2024 9:28 AM, Lawrence Miller via groups.io wrote:

Show quoted text

Carl,
Upon closer inspection, thy do seem to be hand made. I can see the bare metal between the "teeth" The ones with points, there are two of them, the angle appears to be 40 degrees. Neither comes to a sharp point. One shows more wear than the other.

Reading the gauge from left to right:
Number 1 6.25 mm
Number 2? 5.70 mm
Number 3? 5.10 mm
Number 4? 4.50 mm
Number 5? 3.85 mm

There is much smaller gauge which probably does not show up well on the photo I submitted. I has only 4 "teeth" and no numbers. It too seems to be hand made. For me, it is very difficult to measure.

Thanks Carl,
Larry

Re: DB/SL Belt Sizes?

#63305

For those who do not want to muck up their soldering iron:

-227 small drive
-237 large drive

if you want 3/16" wire just get -327 and -337 but honestly I think they are too tight and will trash your bearings.

My lathe came with a single o-ring that would work on one of the motor pulleys and the matching spindle pulley. This was:
-241 no idler.
The 341 o-ring mentioned above is the same size just 3/16" wire diameter instead of 1/8"

I find thew 1/8" wire o-rings are great and have crashed the lathe without them slipping. I tried 3/16" wire andit seemed to not fit in the groove well.

Re: What are these?

#63304

Carl,
Upon closer inspection, thy do seem to be hand made. I can see the bare metal between the "teeth" The ones with points, there are two of them, the angle appears to be 40 degrees. Neither comes to a sharp point. One shows more wear than the other.

Reading the gauge from left to right:
Number 1 6.25 mm
Number 2? 5.70 mm
Number 3? 5.10 mm
Number 4? 4.50 mm
Number 5? 3.85 mm

There is much smaller gauge which probably does not show up well on the photo I submitted. I has only 4 "teeth" and no numbers. It too seems to be hand made. For me, it is very difficult to measure.

Thanks Carl,
Larry

Re: Unimat 3 Vertical Milling Attachment; Pinion

#63303

Hello Timothy,?? I measure my U3 at 12.03 for the hole and 11.95 on the pinion (tooth tip to tip) with 11.97 on the pinion shaft.?? Hope that helps!?? Rgrds,?? Richard.

Re: What are these?

#63302

开云体育

Hello Larry:

Can you measure each gap (1-5)? and tell us the sizes?

Thanks, Carl.

On 7/5/2024 8:39 PM, Lawrence Miller via groups.io wrote:

Show quoted text

That makes sense. These belonged to my step father. Before I was in high school, he was a machinist.? He worked in the machine shop at a local mill. He spent over 40 years there later becoming the foreman .

My mother told me that when he retired he either gave or sold all of his tools. The only thing left was a long tool box. After he passed away, my mother gave me that tool box. The only things in it were two very large and long screwdrivers, a few hand made chisels and a few hand made punches. Carefully packed in a small box were the items I posted. He must have valued them.

Through the years I have shown these to many and no one can say for sure what they were used for. Thanks for the reply.

Larry

Re: What are these?

#63301

That makes sense. These belonged to my step father. Before I was in high school, he was a machinist.? He worked in the machine shop at a local mill. He spent over 40 years there later becoming the foreman .

My mother told me that when he retired he either gave or sold all of his tools. The only thing left was a long tool box. After he passed away, my mother gave me that tool box. The only things in it were two very large and long screwdrivers, a few hand made chisels and a few hand made punches. Carefully packed in a small box were the items I posted. He must have valued them.

Through the years I have shown these to many and no one can say for sure what they were used for. Thanks for the reply.

Larry

Re: Unimat 3 Vertical Milling Attachment; Pinion

#63300

I just got a 12mm pinion blank, but to my surprise it does not fit into the Unimat 3 Vertical Milling Attachment. I measured the opening in the milling attachment and it comes in at 11.8mm. So now I'm trying to determine if the actual pinion for the Unimat 3 is something other than 12mm OD. If someone could measure the opening in their Unimat 3 Vertical Milling Attachment and verify if it is bored to accept 12mm, or if it is less than this, it would be a great help.

Thank you,
Timothy Jump

Re: What are these?

#63299

开云体育

I am just guessing here, but they possibly could be shop-made Acme or square thread gauges.

?

Jerry F.

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Lawrence Miller via groups.io
Sent: Friday, July 05, 2024 6:33 AM
To: Carl; [email protected]
Subject: Re: [Unimat] What are these?

?

Can anyone identify these? There are 4 of them, the larger one with "teeth" is numbered 1-5.

Thanks,
Larry

Re: What are these?

#63298

Can anyone identify these? There are 4 of them, the larger one with "teeth" is numbered 1-5.

Thanks,
Larry

Mystry tools.jpg

Re: What are these?

#63297

开云体育

Hi:

They could be sorting gages, each step is a different size for matching graded parts.

The other option is the could be used as mandrels between centers for certain parts.

Carl.

On 7/4/2024 7:45 PM, Brad Barton via groups.io wrote:

Show quoted text

These came along with my lathe, It came with a lot tooling that looks like they were for a bigger machine and these might not been used with the Unimat.

If I were guess, I would guess gauges of some sort.

Re: What are these?

#63296

I strongly suspect these are a form of "go - no go" plug gauges.? I suspect the various diameter features are a series of slightly different diameters.

Used for inspecting parts.? The knurled handles just facilitate handling them.

I have a different style of a "go - no go" gauge that you can buy commercially but have not ever seen this style.? Maybe they were commercially produced gauges.? Or perhaps made custom in some company.? A lot of places have custom made their own inspection tooling.? I wonder if the application might be automotive.

Charles E. "Chuck" Kinzer

On Thursday, July 4, 2024 at 04:45:33 PM PDT, Brad Barton via groups.io <xbartx@...> wrote:

These came along with my lathe, It came with a lot tooling that looks like they were for a bigger machine and these might not been used with the Unimat.

If I were guess, I would guess gauges of some sort.

What are these?

#63295

These came along with my lathe, It came with a lot tooling that looks like they were for a bigger machine and these might not been used with the Unimat.

If I were guess, I would guess gauges of some sort.

Re: Unimat 3 Vertical Milling Attachment; Pinion

#63294

Sorry, I was thinking of my old SL and didn't notice it was for the U3. Maybe more accurate dimensions will be required for that. Even so, a lot of it could be improvised according to what you want to do. Somewhere in the depths of my garage I have a U3 style milling column which will need a complete rebuild. I'll see what I learn from that.