# Measuring Drill Press Feed Handle for Knobs



## HMF (Jan 14, 2014)

Very stupid question- I apologize in advance.

My drill press that I bought 35 years ago (Enco, made in Taiwan) needs new feed handle knobs.

http://www.use-enco.com/1/1/34994-pulley-driven-geared-head-floor-bench-drill-presses-308-0056.html

Here is the manual:

http://www.use-enco.com/Machinery/125-1142.pdf

I need to know the size hole of the knob and the thread to replace them. I have already sadly bought the wrong sizes once...   :rofl:

I have a prospective supplier:

Essentra (formerly Reid Supply):

http://www.reidsupply.com/products/knobs-handles-hand-wheels/knobs/ball-knobs/


But I need to measure the pull-down feed handle's thread diameter and thickness to know if I need 3/8-16, 10-32, 5/-18. 
I tried using a digital caliper, but I was off, and bought the wrong size. 

What do I need to measure the thread accurately?

Thanks in advance.


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## David S (Jan 14, 2014)

My guess is that it is a metric thread.  You can measure the diameter and the pitch with a metric thread gauge.  The other thing would be to get a selection of metric nuts from the hardware store and see if you can get a match.

David


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## Terrywerm (Jan 14, 2014)

Nels, you know better!! There is no such thing as a stupid question!!

I have a similar drill press, 20 years old or so, made in Taiwan.  Does this one look like yours??   13 inch, 16 speed, 1/2 HP

The threads on the spindle feed levers are definitely 3/8"-16 on mine.

Don't know if it helps, but maybe we'll get lucky on this one?    What sizes have you tried??    The knobs on mine do fit a little tight, but I believe that they are meant to so that they do not vibrate off when it's running.

Please excuse the photo quality. That corner of the garage has a fluorescent fixture in it that refuses to work most of the winter, so I had to use some improvised lighting.




ON EDIT:  I followed your link to the Enco machine, and it is exactly like my machine, except that mine is a floor model. Otherwise everything else is the same according to the specs on the Enco site.  The only thing that is different is that I only paid $140 for mine brand new, about 20 years ago.

UPDATE:  I just went out and threaded a 3/8"-16 nut onto mine - perfect fit.

To answer your question about measuring, I measured the rod diameter first, it was .327"   then measured the OD of the threads, which was .368"  (formed or rolled threads, explains the thread OD being larger than the parent stock)   then checked with a thread gauge, 16 TPI fit perfectly.


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## 12bolts (Jan 15, 2014)

http://www.hobby-machinist.com/show...se-for-golf-balls?highlight=golf+ball+handles

Cheers Phil


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## HMF (Jan 16, 2014)

terrywerm said:


> Nels, you know better!! There is no such thing as a stupid question!!
> 
> I have a similar drill press, 20 years old or so, made in Taiwan.  Does this one look like yours??   13 inch, 16 speed, 1/2 HP
> 
> ...




Terry:

Thank you so much for checking, just for reference, Essentra Components (formerly Reid Supply Co.) has the ball knobs in several diameters- I ordered item No. B-6 1-3/8 inch diameter, 3/8-16 thread, brass insert, phenolic in black,  ($1.76 each), and item DM-85 1-1/4 inch diameter, 3/8-16 thread, brass insert, phenolic in red (the originals were red) $3.38 each. They have other types- it's almost ridiculous how many choices you have there, including soft grip plastic and steel inserts. My originals were very cheap plastic with the threads molded in, no insert, and they cracked from years of use.

For measuring, I assume you used a caliper? And an imperial thread gauge like the sets Starrett sells?


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## HMF (Jan 16, 2014)

12bolts said:


> http://www.hobby-machinist.com/show...se-for-golf-balls?highlight=golf+ball+handles
> 
> Cheers Phil




That's ingenious, I should have searched on here. I don't play golf, and I don't know what balls cost. I bought the ones above for $1.76 and $3.38 each.


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## Tony Wells (Jan 16, 2014)

Every machinist should have a pitch gage. Then all you need is a way to measure the major diameter, and you can identify the thread.





There is a variety of these, some are UN only, some are Metric only, some are both, some are Whitworth, etc. Should be able to turn up something on ebay pretty easily.


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## Terrywerm (Jan 16, 2014)

Yup, I just used a dial caliper as dead on accuracy was not critical. Being off a couple of thou would not make a difference. For checking the thread pitch, I just used a thread pitch gauge, similar to the one shown in Tony's reply. 

I know what you mean about the original knobs cracking, as mine have done that also. I plan to replace them once I get my new shop space in the basement done and get the DP moved down there, but I was thinking of building a ball turning attachment for my lathe, then make my own knobs out of something exotic like teak, ebony or maybe bloodwood. Make them with brass inserts pressed into the blank, then I could simply thread the blank onto a self made 3/8"-16 mandrel in the lathe and turn the balls.  Once sanded and varnished, they should look pretty sharp!


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## HMF (Jan 21, 2014)

The saga of my stupidity continues....  :banghead:


I tried the 3/8-16 knob I got from Reid and it doesn't work- apparently the made the rods thicker back when I bought mine.

The measurements with a digital (Mitutoyo) caliper I got is: 

.4345 for the unthreaded portion of the lever (rod)
.4860 for the top of the threaded portion
.4360 for the indentations in the threads

I used the #472 Starrett thread gauge that I have as per Tony's post, and 11-1/2 was the best fit for the threads on the threaded portion of the lever.


I tried a metric nut, and it goes on a bit.

So...  What size knob is it?  Is it 5/8-18 or 20? Some metric size?  I need to match it to one of the ones that Reid sells.

Thanks for bearing with me, guys.


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## RandyM (Jan 21, 2014)

Nelson,

With the sizes you are quoting I would be inclined to go 7/16-20. Or one of these:

Reid Knobs

But, try a nut on it be for you buy.

Your number is even oversize for 12mm.


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## chuckorlando (Jan 21, 2014)

Yea your in the 7/16 area there. .4375


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## DAN_IN_MN (Jan 21, 2014)

Perhaps going to a GOOD hardware store and picking up a few different nuts in that size range for test fitting would be helpful here.

Or, you could turn them down to fit knobs you already have.


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## darkzero (Jan 24, 2014)

Nels said:


> The measurements with a digital (Mitutoyo) caliper I got is:
> 
> .4345 for the unthreaded portion of the lever (rod)
> .4860 for the top of the threaded portion
> ...



Correct me if I'm mistaken but I don't think it's 7/16-20 or 7/16 at all (he stated that's the unthreaded portion). From what I make out of Nelson's measurements .4860 is the major dia of the threads & .4360 is the minor (as good as his calipers can get into the root of the thread.

.4860 is just over 12mm so it can't be M12. Nelson said he seems to have measured 11-1/2 TPI. 1/2-13 is a common thread size & very common for knobs, 7/16-20 not so much. 13 TPI is a lot closer to 11-1/2 than 20 TPI. .4860 is on the small side for a 1/2-13 thread but that is still within a Class 1A thread (just barely).

Nelson, I think 1/2-13 should be you next try, as mentioned, grab a nut from the hardware store. If you still can't figure it out you could always go with one of these "universal" knobs. You just thread them on & don't need to worry about thread pitch. I've used them in some cases & never had a problem with them. They don't come in Phenolic though.

http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=25223060&PMAKA=328-2365

If you check out the catalog page there's a few different ones like tapered instead of ball & red.


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## Mark Lossner (Feb 1, 2014)

> What do I need to measure the thread accurately?


 I know that this is a late post for something you have already solved, but I took the following approach: Just measure the minimum diameter of the screw with a vernier caliper. Go to an art supply store and acquire wooden balls of a diameter that pleases you. Drill a hole into each one to match the previously measured diameter. A slightly bigger hole will insure that the ball won't split. Now just screw the wooden balls onto the threads of the levers. They thread on nicely and stay put.  Mark


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## HMF (Feb 9, 2014)

As it turned out, the only knobs I could get that sorta fit were 1/2"-13 at Reid Supply. They don't go all the way in (they need to be deeper, but they don't carry that).
Cost me $100 worth of the wrong sizes to learn this. Measuring wasn't that helpful, although by caliper it measured .48.  Thread measured 11 on the thread guage.

Always get the ones that have a metal insert. If you force the plastic threaded ones even the slightest bit, they crack. They will crack from ordinary use when you pull them down. 
Get phenolic with brass threaded inserts.

They don't make 1/2"-11 or a deeper one, so this is the best I can do.

Thanks fellas.


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## jim18655 (Feb 9, 2014)

Do the rods unscrew? Two options if they do - take one to the hardware store to fit a nut or turn down and thread to fit what you already bought.


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## darkzero (Feb 9, 2014)

Nels said:


> Always get the ones that have a metal insert. If you force the plastic threaded ones even the slightest bit, they crack. They will crack from ordinary use when you pull them down.
> Get phenolic with brass threaded inserts.



One of the reasons why I suggested the universal ones. They won't crack like the prethreaded ones you mentioned. The universal ones are not hard like phenolic & the thread forms when screwed on. Thread pitch does not matter, only the diameter range. Perfect for cases like yours.


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## Big Rack (Feb 10, 2014)

What worked for me I purchased a RF30 mill/drill that didn't have any handles price for 3 handles and 3 knobs was kinda high. I went to local hardware store bought 3 long bolts they were metric and I can't remember the size. Stopped by the local driving and asked if they had a few scarred up balls I could buy, they handed me a bag full a couple of dozen or so for nothing. They said they have some means of checking the balance as they use them and these were off. Balls were in great shape.
Now when I was a kid I took apart a couple they were  full of little rubber bands and a ball in the center with liquid but I figured I'd try them clamped the ball with a wooden carpenter clamp with the ball centered in the through hole of my drill press counter bored and drilled through with spade bits. No liquid, no rubber bands just a couple of colors of some sort of rubber material. Drove the bolts through and they work great and a lovely zombie yellow green color.
I don't know if standard balls are made this way but I sure found a source of file and other thingy handles. Can't claim to be an original thougt as I saw somewhere about using them for file handles but was real concerned about spurting goo.
Anyway it works and was cheap.


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## KBeitz (Aug 9, 2018)

Anyone else looking for knobs?
Junkyard garden tractor shifting knobs. 
If they don't fit just heat the shaft and push them on.


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