Link belt slipping on delta DP220 drill press...

[56type]

I restored a Delta DP220 drill press and made my own speed reduction assembly. Offset the pulley a bit from center to allow belt tensioning by the column insert rotating as the motor is tensioned. Herad good things about the link belts so thought I'd give one a try. Picked up a harbor freight link belt along with an aluminium 4-groove pulley off amazon and got the column insert turned on the lathe, drilled & tapped for an axle bolt to mount the pulley with a broze sleeve bearing. Set up look good and function fine until under load...First time use yesterday drilling 0.250 in. hole in some angle steel for another project and the bit would bind and belt would slip or belt would slip & bit would bind in work as a result. Either way the belt is slipping with some frequency. Anyone else run into this ?? the alum. pulley is fairly polished while the spindle pulley & motor pulley is painted cast metal from what I can tell. Don't seem to have much issue with the same belt slipping between the motor drive pulley & alum. speed reduction pulley. The slipping seems to occur between the spindle pulley & aluminum speed reducing pulley.....

 

[dlane]

I restored a Delta DP220 drill press and made my own speed reduction assembly. Offset the pulley a bit from center to allow belt tensioning by the column insert rotating as the motor is tensioned. Herad good things about the link belts so thought I'd give one a try. Picked up a harbor freight link belt along with an aluminium 4-groove pulley off amazon and got the column insert turned on the lathe, drilled & tapped for an axle bolt to mount the pulley with a broze sleeve bearing. Set up look good and function fine until under load...First time use yesterday drilling 0.250 in. hole in some angle steel for another project and the bit would bind and belt would slip or belt would slip & bit would bind in work as a result. Either way the belt is slipping with some frequency. Anyone else run into this ?? the alum. pulley is fairly polished while the spindle pulley & motor pulley is painted cast metal from what I can tell. Don't seem to have much issue with the same belt slipping between the motor drive pulley & alum. speed reduction pulley. The slipping seems to occur between the spindle pulley & aluminum speed reducing pulley.....

Didn’t have that problem with mine , I used roller bearings on the speed reduction pulley when I made mine and used the link belts , tighten the belts for 3/4” deflection when pushed in ,I did have to remove a couple links after 5 minutes of run time.

 

[benmychree]

Is the belt bottoming out in the pulley groove?

 

[darkzero]

I use link belts on my lathe & air compressor but mine are Fenner Power Twist. Link belts stretch a bit since the links settle/interlock tighter when new so after you have run them for a belt recheck the belt tension.

 

[56type]

Is the belt bottoming out in the pulley groove?

Not that I can tell...If anything it seems to be a bit proud of the grooves in the pulley. I retensioned the motor to add some extra tension to speed reduction & spindle pulleys. I don't know that removing links will help as I set the belt length with the motor bracket fully into the housing to account for any strectching of the belt during normal use/wear. Alternatively I had thought of spraying the aluminium pulley with a teaxtured paint similar to used on stairs to provide traction or truck bedliner spray to add some "grip" to it for the belt to bite into ??

 

[pontiac428]

I thought the belt was a little proud, like it's a size too big, but it appears you're getting full engagement. Maybe some break-in time under no load to improve things? My green belts slipped minimally until they ran enough to darken along the contact surfaces, after that they were trouble-free. You are running in the correct belt link orientation. Just give it some time to settle in.

 

[yendor]

Link Belts are directional. Make sure you have them running in the correct direction.
The bulk pack of link belt material I purchased had directions on which way to have it feed.

 

[mattthemuppet2]

I never had any luck with link belts. They're real useful for working out the size of the belt(s) I actually want to buy, but I've only ever had them slipping on both my lathe and drill press. Use the existing link belts to work out what size AX belts you want. They'll wrap around those small pulleys much better and the grip will go way up. On my Walker Turner with a similar speed reduction set up I have to be drilling 1" holes in steel or power tapping 3/8-16 or above to get the belts to slip. I also use an AX belt on my mill, but I've changed my lathe to polyV which grips way better than pretty much anything else.

Another thing work looking into also is the speed you're running that drill at. That looks like the lowest speed setting (200rpm?), so it might be worth going up to 5-600rpm or so. That'll get you better belt wrap and less chance of slipping.

 

[hman]

Link Belts are directional. Make sure you have them running in the correct direction.
The bulk pack of link belt material I purchased had directions on which way to have it feed.

Durn it, none of the packages I've seen have ever included directional info! Had to do a web search and really dig for it. Finally found the info, and now use the mnemonic, "Tabs trailing." Maybe "Tails trailing" would be more specific.

PS - I've always had good results with link belts.

 

[darkzero]

I run the Fenner Power Twist belts & they have directional arrows on the links. I posted in a recent thread that I run them in reverse often even though not recommended by Fenner. Never had a problem running in reverse, just a bit noisier is all.

I've had good luck with link belts too. They cured a surface finish/harmonics problem I had on the lathe. I even run my link belts a bit loose, well looser than I would a standard v-belt, never had them slip. My lathe has dual belts though. I run one on my air compressor too but only cause I had enough left over. No benefit on the compressor, whatever belt was on it was too long.