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RG1911
01-01-2018, 02:30 PM
I finally have my 1946 Delta drill press with the 220 head cleaned and back together. However, the V-belt that was with the DP seems to have way too much slack. I have a copy of the original owner's manual, which does not provide the necessary information, and an internet search using various terms has proven to be fruitless (and frustrating).

Does anyone know how to determine the correct V-belt size and cross-section?

Thank you (and Happy New Year!),
Richard

pworley1
01-01-2018, 02:53 PM
One way is to measure across the inside top of the pulley to get the width, and to measure the length of rope it takes to reach around the pulleys to get the length. Take those numbers to the store and they should be able to get you the correct belt.

alamogunr
01-01-2018, 03:51 PM
You might consider those segmented type belts. Not cheap but well worth the money. I've got them on both the drill press and tablesaw. The above tip for determining length would work since you buy by total length, so much a foot I believe.

MyFlatline
01-01-2018, 04:17 PM
rope the size of the pulley groove works well

abunaitoo
01-01-2018, 04:34 PM
Yep, use a rope to find the length.
Measure the width of the pulley to find the width of the belt.
That's an old one.
A picture would be nice.

W.R.Buchanan
01-01-2018, 04:59 PM
The belt is an "A" Belt size. There are "B" and "C" belts as well which are used for higher HP applications..

To determine the correct length,,,, Measure the Dia of both pulleys, then Pi x d for the circumference and then divide each by 2, and add together.

Then measure the distance between the shafts when the take up adjustment is halfway in it's travel. Double it and add to the pulley measurements.

If the machine has multiple pulleys use the center ones for the measurements.

This will give you the length needed. I would suggest going to a Bearing House for your belts and they will have them available in 1-2" Length increments and the necessary width sizes.

Hope this helps

Randy

country gent
01-01-2018, 05:12 PM
Make sure the adjustment isn't all the way down the motor should be on an adjustment set up so belt can be easily moved from pulley steps to others for speed adjustment. My little table top has about 2" adjustment for this. A piece of rope works to get length as does a cloth sewing tape measure. measure around the pulleys on the outside then around the outside of the vee belts. As mentioned above the belt is very likely a A belt size. It takes a big drill press to get into B or C belts. and they are more motor drives to a gear head press.
Your delta drill press is a good solid machine and most deltas spindle return spring is adjustable for tension. It can be adjust to just barely bring the spindle up to a real slam when it hits the stop. A good solid machine that holds up well.

RG1911
01-01-2018, 06:57 PM
The belt is an "A" Belt size. There are "B" and "C" belts as well which are used for higher HP applications..

To determine the correct length...
Randy

Randy, terrific! Many thanks.

Here are a few images (press still needs a bit more cleaning).

210867

210868

210869

210870

210871

This press apparently was supplied with either a high-speed or a low-speed pulley. Unfortunately, nothing I have found gives the diameters of the two pulleys, and neither has any part number. Because the spindle pulley is larger than the motor pulley, I am *assuming* that I have the low-speed model.

Speaking of the motor, it's a Sear and Roebuck motor (of the correct RPM and horsepower), so again I'm assuming it's a replacement; particularly since the switch has been moved to the side in a standard-size switch box.

I'm grad this is a sturdy (the table alone weighs 50 pounds), well-made press, because I suspect replacement parts would be a witch to find.

Cheers,
Richard

W.R.Buchanan
01-01-2018, 08:18 PM
Rich: the Low Speed models have a Secondary Reduction. IE: Three pulley sets and two belts.

The problem with the vast majority of Drill Presses is that they simply run too fast. Hence the low speed versions. Most you see are high speed versions because most people don't pay attention to this small but important detail or just don't know.

My Craftsman DP has the Secondary Reduction, but didn't come with it. I found another Craftsman DP and scalped it and put it onto my good DP.

The other pulley set fits into the top of the column and is eccentric so that it can make primary belt tension, then the secondary belt tension is done by moving the motor.

I bet that if you found the parts that they would work for yours as well. Craftsman and Delta are pretty similar.

Here's a pic:

For drilling steel a 1/2" bit needs to be running around 300 rpms. No size drill bit needs to run any faster than about 700 RPMs for drilling steel until you get below about 1/8" then they work best faster, which cuts down on the chip load, and thus the stress on the bit.

You'll note that my DP is set on the slowest possible speed. I never change it because I mainly use it for countersinks which need to run slow.

For Aluminum or Brass just about any speed will work.

The thing about Drills is you can always go slower, but most times faster is too much and especially in steel or harder metals.

Randy

RG1911
01-01-2018, 09:24 PM
Rich: the Low Speed models have a Secondary Reduction. IE: Three pulley sets and two belts.
Randy

Randy,

Thank you. I saw several pictures of the secondary reduction system, but they were not identified as being the slow speed version. Actually, two of the parts breakdowns for the 14-220 head listed two different pulleys; one identified as slow-speed and one as high-speed. Somewhere I read that the slow-speed spindle pulley was larger than the motor pulley.

Questions: When you say to measure the pulley diameters/circumferences, do you measure the largest diameter of both pulleys?
Why would I look for v-belts at a company that makes bearings? (And doing a search for "bearing house" just got me bearings.)

Thank you,
Richard

country gent
01-01-2018, 10:12 PM
The one size adjustable belts tend to run smoother with less warm up needed for them to smooth out. Not a big issue on a drill press but on other machines it can be an issue. standard vee belts that sit awhile take a set and run rougher until they warm up some.

ulav8r
01-01-2018, 11:26 PM
Measure the largest diameter of one pulley and the smallest diameter of the other pulley. That is the way they will be used, one with the largest diameter up when installed, the other with the largest diameter down, and the belt horizontal.

country gent
01-01-2018, 11:49 PM
In the first shop I worked in high school we had a lot of flat belt ran equipment. I still remember the tic tic tic of the lacing on the pulleys when it came around. Vee belts are a big inprovement

john.k
01-01-2018, 11:58 PM
The motor slides back and forth to tension the belt,right?........There is a lot of margin for belt length there,and I suspect with the motor pushed right in,as shown,that simply running a tape measure around both pulleys will get a suitable length...........bearing houses do sell belts,only to desperate people......get on off ebay for a tenth of the price.

RG1911
01-02-2018, 12:54 PM
The motor slides back and forth to tension the belt,right?........There is a lot of margin for belt length there,and I suspect with the motor pushed right in,as shown,that simply running a tape measure around both pulleys will get a suitable length...........bearing houses do sell belts,only to desperate people......get on off ebay for a tenth of the price.

Regrettably, with the replacement motor, there is almost no way to remove slack. I don't know how the system worked with the original motor. There is a small bolt at the bottom of the mount that lets you tilt the motor forward and back a very tiny amount. I can't tell if it is a part of the original system, or if it's a kluge with the new motor. Old parts drawings don't show it.

Cheers,
Richard

RG1911
01-02-2018, 12:55 PM
Measure the largest diameter of one pulley and the smallest diameter of the other pulley. That is the way they will be used, one with the largest diameter up when installed, the other with the largest diameter down, and the belt horizontal.

Thank you for confirming how I thought the measurement should be done.

Cheers,
Richard

RG1911
01-02-2018, 01:01 PM
The one size adjustable belts tend to run smoother with less warm up needed for them to smooth out. Not a big issue on a drill press but on other machines it can be an issue. standard vee belts that sit awhile take a set and run rougher until they warm up some.

I had not heard of adjustable belts. Considering that the drill press will not be used on a daily basis, I think I will investigate the adjustable ones if they don't take a set.

Thank you,
Richard

RG1911
01-02-2018, 08:11 PM
Originally Posted by john.k View Post
The motor slides back and forth to tension the belt,right?........There is a lot of margin for belt length there,and I suspect with the motor pushed right in,as shown,that simply running a tape measure around both pulleys will get a suitable length...........bearing houses do sell belts,only to desperate people......get on off ebay for a tenth of the price.
Regrettably, with the replacement motor, there is almost no way to remove slack. I don't know how the system worked with the original motor. There is a small bolt at the bottom of the mount that lets you tilt the motor forward and back a very tiny amount. I can't tell if it is a part of the original system, or if it's a kluge with the new motor. Old parts drawings don't show it.

Okay, time to admit that I have suffered from operator headspace error (as we said in the computer business). The civilian version is "I'm an idiot."

I was looking at the motor mount when the lightbulb started glowing, I slapped my head, and said "So that's how it works!"

The mount does, indeed, slide on two large-diameter pins that have lock bolts to hold the mount in place. I didn't pay close attention to the system when I disassembled and reassembled the unit.

Don't get old.

Richard

Chill Wills
01-03-2018, 02:39 AM
Bingo. you got it.
Yours is a DP-220 I think. I have one, but older. The belt adjustment is just like you described and maybe not the fastest but does have a lot of room to adjust. Plus once locked back in it is bomb proof.
Yours looks like a good clean up or good restore job on your part. Nice.

Mine is my second floor drill press (back up) to my larger one and I got it from Craig's list $50 in poor shape knowing I would clean and restore it. There are parts a plenty on ebay should you need them. The only costly one is if you need a spindle pulley with the bearing. That is the keystone part. Everything else is available for a fair price.

I am attracted to old American iron. It makes me feel good to see these old tools put back into service. Looks like you'll have a great floor drill press.

BigEyeBob
01-03-2018, 03:19 AM
I had not heard of adjustable belts. Considering that the drill press will not be used on a daily basis, I think I will investigate the adjustable ones if they don't take a set.

Thank you,
Richard

Its called power twist and can be adjusted in length by handwith no tools
neccesary

Chill Wills
01-03-2018, 01:17 PM
Its called power twist and can be adjusted in length by handwith no tools
neccesary

Are these kind of belts (in design) the same as can be put on flat belt applications? (Not V belt for Flat belt but flat for flat and V for V) Like the old lathes South Bend and all?

john.k
01-03-2018, 09:48 PM
In these old drill presses,everything runs true because they were made that way....buy a new Chinese one and the spindle has .015 runout,chuck has .015 runout,table adjustments wont hold,and they use tiny belts to get multiple speeds.And they use minimal size bases meaning they must be secured or tip over (un)expextedly.

Shopdog
01-05-2018, 06:44 AM
Sounds like you're getting the drill press up N running.You won't be disappointed.We're a Walker Turner shop.

Reason for post,look up Baltimore Belting,25th st....they are the guys when it comes to serious vintage "arn".

w5pv
01-05-2018, 02:40 PM
Remember that the sides of the belt do the pulling not the bottom of the V,keep the V up and off the bottom

RG1911
01-06-2018, 09:20 PM
Remember that the sides of the belt do the pulling not the bottom of the V,keep the V up and off the bottom

Thank you. I was not aware of that.

Richard

RG1911
01-06-2018, 09:21 PM
Sounds like you're getting the drill press up N running.You won't be disappointed.We're a Walker Turner shop.

Reason for post,look up Baltimore Belting,25th st....they are the guys when it comes to serious vintage "arn".

Slowly getting it up and running. Will be using it to build my new, rather massive, reloading bench.

And I'll certainly look up Baltimore Belting.

Thank you,
Richard

W.R.Buchanan
01-09-2018, 04:51 PM
Richard: the reason you go to a bearing house to buy your belts is because they usually have a large selection of belts in 1" increments.

I didn't mean shopping Bearing Houses on the internet I meant physically going to a Bearing House and finding the belt you need.

Doesn't your parts break down give a belt dimension?

Randy