Clean & Repaint of a Rockwell 21-122 Horizontal/Vertical

keeena

H-M Supporter - Gold Member
H-M Supporter Gold Member
Joined
Jun 10, 2019
Messages
166
I found your thread/watched your vids after posting an unrelated thread in this Rockwell forum. I liked the "rebuild" series - neat mill! Love to have one in my garage - its on the list. :)

For tapping or threading SS, I learned the hard way too. You definitely need quality taps/dies. The cheapos are garbage compared to quality brands. Buy once cry once. A long taper (starter tap) is a must. A 2- or 3- flute tap (vs. 4 flute) can also help.

What size drill were you using? On harder materials you can go with a smaller thread engagement (which means larger drill size). For 1/4-20 at the usual 75% thread you'd be using a #7 index. But for SS you could go as low as 60% thread and be plenty strong. But say 65%: you'd be at a #5 index. This little bit of extra size helps. (I should note: i'm just a hobbyist, but this is straight forward info from machinery handbooks).

One other thing I found useful on SS is a mix of tapping fluid and anti-seize. Picked this up from a vid on youtube and seemed to work better than straight cutting fluid for me.
 
Last edited:

polyfractal

Registered
Registered
Joined
Dec 8, 2017
Messages
16
I found your thread/watched your vids after posting an unrelated thread in this Rockwell forum. I liked the "rebuild" series - neat mill! Love to have one in my garage - its on the list. :)

For tapping or threading SS, I learned the hard way too. You definitely need quality taps/dies. The cheapos are garbage compared to quality brands. Buy once cry once. A long taper (starter tap) is a must. A 2- or 3- flute tap (vs. 4 flute) can also help.

What size drill were you using? On harder materials you can go with a smaller thread engagement (which means larger drill size). For 1/4-20 at the usual 75% thread you'd be using a #7 index. But for SS you could go as low as 60% thread and be plenty strong. But say 65%: you'd be at a #5 index. This little bit of extra size helps. (I should note: i'm just a hobbyist, but this is straight forward info from machinery handbooks).

One other thing I found useful on SS is a mix of tapping fluid and anti-seize. Picked this up from a vid on youtube and seemed to work better than straight cutting fluid for me.

Thanks for watching! I'm pretty happy with the little Rockwell. There are definitely times that a larger Bridgeport would be nice, but generally it does what needs doing, just need to slow down sometimes.

I hear ya with quality taps! After destroying all those cheapo taps I bought a bunch of new-old-stock quality taps off ebay. Life has been much happier since then :) Also got some spiral taps which have been nice as well.

To be honest, I don't remember what drill I used... but I think I was on the "more engagement" side of things. I've never been sure how much is needed and opt for more over less. I'll try less engagement next time in a hard material like SS, not sure why I didn't think about that. Thanks for the tip!

Will try the anti-seize too! That's a really clever idea
 
It can take up to an hour for ads to appear on the page. See our code implementation guide for more details. If you already have Auto ad code on your pages there's no need to replace it with this code
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock