M-25 Belt slipping in drill press


I was doing some drilling with my drill press yesterday, using an MT2 shank
25/32" bit @ 300RPM (and plenty of cutting fluid). It was just for
experimenting, as I have never used a bit that large before, and wanted to
see how my new press would handle it.
Everything went well, except that the front (idler pulley to spindle pulley)
v-belt (size M-25) would slip the idler pulley (spindle would stop) if I
applied too much pressure. This meant that I had to peck at it, which isn't
what I am looking to do.
So, as this is a used press, I considered getting a new belt, but it is hard
locating an M-25 belt, especially locally, and even online (couldn't find
one at mcmaster carr) From what I can tell, the M refers to the large width
being 10mm, and the 25 refers to a 25" circumference. Would a 3/8" (9.52mm)
belt work in this application?
What I would like is a belt that was less prone to slipping when I drill
large-ish holes (13/16" is the size I will be doing a lot of in the near
future). Would a cogged belt be a good solution for this? Any other
less-slippy belt suggestions?
Thanks,
Jon
Reply to
Jon Danniken
Loading thread data ...
M-25; Z-25 or 3/8-25 All nominally the same section AFAIR
Have you tried just tightening it a bit more?
Mark Rand RTFM
Reply to
Mark Rand
Are you exceeding the drilling capacity in steel vs.HP spec of the drill press?
Bob Swinney
I was doing some drilling with my drill press yesterday, using an MT2 shank 25/32" bit @ 300RPM (and plenty of cutting fluid). It was just for experimenting, as I have never used a bit that large before, and wanted to see how my new press would handle it.
Everything went well, except that the front (idler pulley to spindle pulley) v-belt (size M-25) would slip the idler pulley (spindle would stop) if I applied too much pressure. This meant that I had to peck at it, which isn't what I am looking to do.
So, as this is a used press, I considered getting a new belt, but it is hard locating an M-25 belt, especially locally, and even online (couldn't find one at mcmaster carr) From what I can tell, the M refers to the large width being 10mm, and the 25 refers to a 25" circumference. Would a 3/8" (9.52mm) belt work in this application?
What I would like is a belt that was less prone to slipping when I drill large-ish holes (13/16" is the size I will be doing a lot of in the near future). Would a cogged belt be a good solution for this? Any other less-slippy belt suggestions?
Thanks,
Jon
Reply to
Robert Swinney
First try to clean the belt.May have years of oil and dirt on it. Perhaps IPA, ispropal alcohol, get at any drug store. Check for glazed spots where the belt has slipped a lot and particularly clean there. Other possibility is the belt may be old and stiff and has a spot with a permanent curved hard spot. That may mean a new belt. Also clean the pullies.
Paul
Reply to
co_farmer
Belt is dry and clean and the pulleys are clean. There don't appear to be any glazed spots. I did measure the outer circumference and found the 25" inch belt to be 25.75, so perhaps it has stretched a bit, and this is indicative enough of the need for a new belt.
I'm still not sure if a 3/8" belt will work, but I'm going to pick one up and try it. I'm also still not sure if an cogged v-belt (if that is the correct nomenclature) belt is "grippier" than a flat belt, but since the cogged belt is in stock, I'll pick one up anyway.
Thanks for the suggestions,
Jon
Reply to
Jon Danniken
Was the hole drilled trough already to allow the web to pass ?
I work up on drills - not every size but plenty. If important I might use number, fraction, letter, metric and do a fine cut at the last.
Remember the center of the drill mostly pushes with a turn. the outside has the surface length to turn. Without a center hole the center of the drill has to cut or mush out to be cut the core as wide as the web diameter.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net "Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufk> I was doing some drilling with my drill press yesterday, using an MT2 shank
Reply to
Martin H. Eastburn
What Martin sez. It never ceases to amaze me people that take numerous passes in a lathe seem to expect a drill of any size to cut cleanly and efficiently in one big thrust. It takes a finite amount of power to remove a given amount of metal whether it be in one pass or many passes. A twist drill is a poor cutting tool compared to a lathe bit.
Bob (call me a pecker) Swinney
Was the hole drilled trough already to allow the web to pass ?
I work up on drills - not every size but plenty. If important I might use number, fraction, letter, metric and do a fine cut at the last.
Remember the center of the drill mostly pushes with a turn. the outside has the surface length to turn. Without a center hole the center of the drill has to cut or mush out to be cut the core as wide as the web diameter.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net "Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufk> I was doing some drilling with my drill press yesterday, using an MT2 shank
Reply to
Robert Swinney
in a lathe seem to
It takes a finite
many passes. A twist
If you have a split point drill bit, you have a lot less force needed, because it cuts right to the center. (Not as efficiently near the center, but enough to make a big difference in performance.
Enjoy, DoN.
Reply to
DoN. Nichols
Aye, I always at least use a spotting bit the diameter of the web. In thic case, there was actually a full through hole, 7/16" in diameter.
Aye, thanks Don. The Silver/Demming bit I will be using for my 13/16" holes is indeed a split point.
Jon
Reply to
Jon Danniken
I tied getting an M-25 belt, but nobody in town carried one. I ended up getting a Gates belt from Napa in 3/8" instead (3L250).
Although I was concerned that it wouldn't be wide enough, it was actually wider than the supposedly "M" belt that I had on there before, actually measuring about 10mm. The sides of the new belt are nice and grippy, and I don't think I'm going to be having any more problems with that belt slipping.
Jon
Reply to
Jon Danniken
My husband has been searching for an M-25 with no luck. He'll take your suggestion of 3L250 Napa belt. But yet another problem - do you know the size of the other belt required for the Mark 1 drill press? The old one disintegrated, so no way to measure. The drill press model # is C-114FX - spindle mount #2.
Liz
Reply to
Liz Cady

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