My 9A-#16490 NKR

[silverhawk]

When doing the bed (or any surface that mattress with another), don't sand blast it unless you can protect the ways.

joe

 

[finsruskw]

Sand blast will be for the cabinet only, after the guts are all removed.
I'm thinking a little darker shade of grey to compliment the lighter color of the components.

Got the bed off and the gear box and head removed yesterday.
Will take the power washer to the bed today hopefully then mask, paint and set aside for now.
I'm gaining on it slow but sure.

 

[Karlito26]

Nice project. I love it when people restore older machines.
Question for all: on the carriage, inbetween the ways there are two 5/16 x 18 bolt holes. What are they for?

 

[finsruskw]

You mean on the back side of then saddle?
I wondered that myself.
Maybe something to do with a taper attachment?
I'll bet it's for that, part #10, bed bracket

 

[Karlito26]

Not on the backside but in the middle of the saddle. Inbetween the ways. On the last pic below the compound rest.

 

[derf]

That's for a follower rest.

 

[Karlito26]

My mystery solved! Thank you.
How often is something like that needed?

 

[finsruskw]

My 33/64" bit and M14 x 1.5 tap showed up this week so one of the projects today is finish the "tee" nut for the compound on the 9A.
Will be using the mill to drill and would like to power tap the hole once drilled.
Couple of questions here.
Is there a rule of thumb as to what size pilot hole to pre-drill for larger bits?
I plan on using a small end mill for a pilot hole, good idea or bad?
The slowest my mill will turn is 80 RPM, is this to fast for tapping a hole this size?

Thanks?

 

[finsruskw]

Tee nut is finished and I got the bed cleaned up and painted today
This is before primer & paint

 

[brino]

Sorry for the delay, I stopped getting notifications on updates to threads I "watch".

I know it's too late for your top-slide t-nut since you showed it complete above, but it may be useful in the future.

Did you power tap it? How did it go?

Is there a rule of thumb as to what size pilot hole to pre-drill for larger bits?

I like the chart from Little Machine Shop. I printed and laminated a copy and keep it in the shop.
The web page here shows only the imperial sheet: https://littlemachineshop.com/reference/tapdrill.php

However, if you download the PDF from this link on that page:



You get a PDF version with two pages Metric and Imperial.

What I like about that chart are the two recommendations for 75% thread or 100% thread depth.
You can choose what fits the application.

-brino