Holding 'thin' parts for off centre hole making.

[PaulR]

You can often use the front face of the tailstock barrel. With 3-jaw work I grip the job lightly, push it in a bit with the tailstock then tighten.

Another useful tip, thanks!

[Zephyrin]

clamping a part by the tip of the 3 or 4 jaws alone is difficult, as this part is often worn, and the presence of a bevel generally prevents effective clamping if the part is very thin...
gluing, screwing or tin welding the part to a support is preferable in my opinion.

[PaulR]

clamping a part by the tip of the 3 or 4 jaws alone is difficult, as this part is often worn, and the presence of a bevel generally prevents effective clamping if the part is very thin...
gluing, screwing or tin welding the part to a support is preferable in my opinion.

Yes, thanks for this. When I get time I'm going to make a small fixture plate, I just need to work out how to position holes and what size clamps I'll need for the most versatile solution.

[90LX_Notch]

Paul-

Don’t over think it, start simple. You can take a block of scrap, square it and add two tapped holes to get a job done. 

I’ve included a photo of my junk.  The angle plates were acquired over the years at swap meets.  The one in the foreground is what I copied the hole pattern for my shop made plates.

The hole pattern that I use for my “standard” is .500 apart left to right.

The rows are .250 apart from each other and the first hole of every other row is shifted .250. 

Everything pictured is a “system” that includes plates, clamps, datum points, spacers etc.  Some of the plates are sacrificial, others are not.

All of the holes pictured are 10-32.

If you search for my build entitled “First I.C. build “Tiny”” there are a bunch of photos with stuff in use.  Also, my “GDB Inline 4 Cylinder OHV I.C.” thread shows some.

-Bob

[steamer]

Take a good look at this video......

I'm going to go this way for thin parts...

Dave

<a href="https://www.youtube.com/watch?v=W7jZO3ZTd0Q" target="_blank">http://www.youtube.com/watch?v=W7jZO3ZTd0Q</a>

[90LX_Notch]

Dave-

This is easier to make, it is my rendition of a Spider.  It has set screws that can be adjusted for part thickness.  A surface plate and indicator are used to assure that the set screw tips are all in the same plane.   Different length set secrets can be used as needed. 

I threw the quarter in for the picture.  If I adjust the set screws, I should be able to face both sides of the  quarter.

-Bob

[90LX_Notch]

Both sides faced, taking it from .067 thick across the center to .045.

[crueby]

The set screws are a clever idea!   




Hmm, adjusted for deflation and thinning, is that quarter now a dime?!   

[90LX_Notch]

Thanks Chris.

[PaulR]

Don’t over think it, start simple. You can take a block of scrap, square it and add two tapped holes to get a job done. 

Thanks for the info and photos Bob. Having returned to the hobby 6 months ago starting from absolute scratch (almost no equipment or materials) the issue I have at the minute is lack of scrap and the price of stock has really increased in the last decade so I need to think carefully before cutting up new material. I wish I still had the big blocks and plates of steel and assorted castings I'd accrued last time I was involved but it all went when I sold up. 

I think you can still be hung, drawn and quartered for doing that to coins of the realm here in GB 

[Admiral_dk]

I think you can still be hung, drawn and quartered for doing that to coins of the realm here in GB 

That is still the case here in Denmark - but I haven't heard of any actually being convicted for that Crime the last 50 years ....

I can't remember who to Credit for this idea (came from YouTube) :

The Four Distance spacers can be moved to the outer threaded holes and lightly skimmed - WITHOUT the Jaws installed => Very precise.

Per       

[Jo]

I think you can still be hung, drawn and quartered for doing that to coins of the realm here in GB 

Only if you are a man, women were burnt at the stake 

Catherine Murphy was the last English woman burnt at the stake for counterfeiting in 1789, the Treason Act of 1790 changed it to merely drawing and hanging for women caught counterfeiting, the drawing bit (and the hung, drawn and quartered bit for men) was kept to entertain the onlookers until 1870.   

Jo

[PaulR]

Only if you are a man, women were burnt at the stake 

Discrimination! 
It didn't stop it happening though (I've written about lots of cases in my books https://www.lulu.com/spotlight/books_by_paul_robinson).

[Admiral_dk]

OK - I better fess up a bit !!!!

Damaging the Danish currency (and I wasn't even referring to counterfeiting) - Bills and Coins - can be punished by quiet a lot of Jailtime .... but not Capital punishment !!!!

That can be as little as bending a coin or writing on the Bills - but as previously mentioned - I don't remember anybody being prosecuted for that kind of offence the last 50 years.
There might been a good number who got to pay a Fine - but that doesn't make the news ....

[steamer]

Dave-

This is easier to make, it is my rendition of a Spider.  It has set screws that can be adjusted for part thickness.  A surface plate and indicator are used to assure that the set screw tips are all in the same plane.   Different length set secrets can be used as needed. 

I threw the quarter in for the picture.  If I adjust the set screws, I should be able to face both sides of the  quarter.

-Bob

I like that!