New to me Hartford Mill
- Thread starter Susquatch
- Start date
Talked to H&W today. Seems their offer to have customers call and get help is limited to "what part number do you want and what is your credit card number". Pretty disappointing really.
All they would do is tell me that their belts and pulleys were different depending on HP and mill model. They didn't want to help find the appropriate parts based on specifications or dimensions. The trouble is that I don't know what model Bridgeport model has the same back gear belt and pulley as my Hartford. I can measure it, but I don't know which one that corresponds to. I do know that my step pulley Hartford does NOT have the same belt or pulley as a step pulley Bridgeport. They also thought it wouldn't be the same as the 2HP vari speed because it has round cogs. They didn't offer to read part numbers off of their belts in inventory. However, they will take the parts I received back - except for the belt which was part of a kit.
Does anyone here happen to know if any model of Bridgeport uses a belt and pulley that matches these specs:
Bando Synchro 230 H 125 G 1 G
According to Bando's web site, that all means that the belt is a type G belt 23" long and 1.25" Wide. But I could not find a belt on their website that matches my specs.
By my measurements, the pitch is 1/2", and there are 46 teeth, and the cogs are 0.25" root-to-root.
I suppose I can use the existing belt and pulley for now, but it won't last for long. The back of the belt is already starting to erode away.
All they would do is tell me that their belts and pulleys were different depending on HP and mill model. They didn't want to help find the appropriate parts based on specifications or dimensions. The trouble is that I don't know what model Bridgeport model has the same back gear belt and pulley as my Hartford. I can measure it, but I don't know which one that corresponds to. I do know that my step pulley Hartford does NOT have the same belt or pulley as a step pulley Bridgeport. They also thought it wouldn't be the same as the 2HP vari speed because it has round cogs. They didn't offer to read part numbers off of their belts in inventory. However, they will take the parts I received back - except for the belt which was part of a kit.
Does anyone here happen to know if any model of Bridgeport uses a belt and pulley that matches these specs:
Bando Synchro 230 H 125 G 1 G
According to Bando's web site, that all means that the belt is a type G belt 23" long and 1.25" Wide. But I could not find a belt on their website that matches my specs.
By my measurements, the pitch is 1/2", and there are 46 teeth, and the cogs are 0.25" root-to-root.
I suppose I can use the existing belt and pulley for now, but it won't last for long. The back of the belt is already starting to erode away.
Try calling MSC. Maybe they will measure their belt for you.
https://www.mscdirect.com/product/details/53323036
https://www.mscdirect.com/product/details/53323036
Will do.
MSC didn't need to measure any belts. They knew exactly what I was looking for. Unfortunately, they have no stock.
But........ drum roll please.......
They called Bando who said that they will make me a belt within a week and ship direct to me for $17 US.....!!!!
Hardly believable!
I ordered two. And felt guilty about that! Prolly should have got ten!
They also gave me the name of a guy who will make me a pulley using 3D printing. I think I'll pass on that one. I'll use the old pulley as is till I decide which mill to keep. If I keep the Hartford, I'll use the pulley till it dies and then replace the pulley, belt, and spindle pulley hub as a set despite the high cost.
There are still companies out there that have proper customer service, despite everything going digital and online (online only in some cases) - good on MSC.
This is a prime example why it will never be possible to replace a human with a brain, that they are willing to use, with a robot… Sorry, I digress.
Glad you found a solution.
This is a prime example why it will never be possible to replace a human with a brain, that they are willing to use, with a robot… Sorry, I digress.
Glad you found a solution.
Based on what happened on my Bridgeport (broke an endmill because the gibbs were too loose, I decided to tighten up the Gibbs and backlash on the Hartford too.
Not happening. Gibbs are about as tight as I would want them as is.
However, I was able to tighten up the backlash a bit. It was 20 on the X axis end to end and 9 on the y end to end. Now it is 5 on the X and 3 on the y. I could probably get the X down to 3 as well, but I could feel it dragging a bit so I backed it off till there was no drag and that ended up being 5. I called that great and left it alone.
While I was in there though I noticed a few things. It looks like the lock screw has a robertson/flat combo head. I always thought that the Robertson head screw was uniquely Canadian........ If so, how did that get there???
It also works in some funny way. It doesn't seem to lock the face of the big screw. Instead it locks something inside the nut somehow. Without a reason to take it apart, I may never know.
I also noticed that unlike my Bridgeport, the dents and dings on the table surface have not been stoned. I will have to do that sometime soon. Certainly before I put a vise on it.
Not happening. Gibbs are about as tight as I would want them as is.
However, I was able to tighten up the backlash a bit. It was 20 on the X axis end to end and 9 on the y end to end. Now it is 5 on the X and 3 on the y. I could probably get the X down to 3 as well, but I could feel it dragging a bit so I backed it off till there was no drag and that ended up being 5. I called that great and left it alone.
While I was in there though I noticed a few things. It looks like the lock screw has a robertson/flat combo head. I always thought that the Robertson head screw was uniquely Canadian........ If so, how did that get there???
It also works in some funny way. It doesn't seem to lock the face of the big screw. Instead it locks something inside the nut somehow. Without a reason to take it apart, I may never know.
I also noticed that unlike my Bridgeport, the dents and dings on the table surface have not been stoned. I will have to do that sometime soon. Certainly before I put a vise on it.
Dabbler
ersatz engineer
So the use of 'square drive' in the US has a spotted history. When Robertson got his patent, Ford wanted to buy a licence to use it in his cars... but the contract terms were very unfavourable, so he told Ford to take a walk. Several years after, 'square drive' screws began to be manufactured in the US - in vioation of the patent - but you have to have very deep pockets to defend a patent, etc.
The patent ran out years ago, as we don't have provisions to renew things in quite the same way as the US, and the primary is here, so it can't be diddled there either.
TLDR the combo drive (which sucks big time) is being manufactured for the US market (primarily), usually offshore. Terrible fasteners, Worse than Phillips.
The patent ran out years ago, as we don't have provisions to renew things in quite the same way as the US, and the primary is here, so it can't be diddled there either.
TLDR the combo drive (which sucks big time) is being manufactured for the US market (primarily), usually offshore. Terrible fasteners, Worse than Phillips.
Agreed totally. Even the Japanese recognized the deficiencies of the Philips and came up with an improved Philips system that they called JIS. On first glance, they look just like a Philips. But they have a blunter shallower tip that is designed to reduce camming out.
Every mechanic should have a set of JIS drivers in their tool chest and be always careful to use the right driver for the fastener.
I personally prefer Torqs, hex, and then Robertson (in that order) for my screws and will go out of my way to get and use them whenever possible.
Ya, I do use more bolts than screws. And I do confess I have loved the torx bolts when I find them.
Anyway, my point was really only that I hate Philips and slotted.
I wouldn't need a new pulley on my Hartford if only they had used something other than Philips..... That @#&!$% screw cost me hundreds....... For what it's worth all 8 got replaced with hex. No Torx available.
Anyway, my point was really only that I hate Philips and slotted.
I wouldn't need a new pulley on my Hartford if only they had used something other than Philips..... That @#&!$% screw cost me hundreds....... For what it's worth all 8 got replaced with hex. No Torx available.
What's screws got to do with having to replace a pulley?
Have to remove pulley flange to get belt off. Have to remove screws to get pulley flange off. One screw was seized in the pulley and Philips head wasn't strong enough. Had to drill it out and use a screw extractor. Screw extractor split the screw stub and split screw stub split the pulley and broke a tooth off.
It's a bad design from beginning to end. The pulley appears to be sintered metal. If it's a casting, it's a really crappy one. Flange screw holes are way to close to the teeth. They should have been set much further back. Even the flanges are poor quality. The Philips head screws were just the icing on a rotten cake.
In hind sight, I wish I just drilled the head remnant off, left the stub in there, and drilled a new screw hole further back where it belongs. But life is seldom like that.......
Had some time left after fixing the neutral on the speed shift Lever on my Bridgeport. I decided to clean and stone my Hartford mill table.
It wasn't nearly as bad as I feared. There were only a few spots the previous owner hadn't already stoned. It cleaned up very nice.
Nowhere near like a new table, but pretty darn good for an old one! There is a lot to like about this mill. The low backlash and low wear on the Gibbs are awesome.
Can't wait for the new back gear belt to arrive....... I would love to be using it and get a decision on which one to keep behind me.
It wasn't nearly as bad as I feared. There were only a few spots the previous owner hadn't already stoned. It cleaned up very nice.
Nowhere near like a new table, but pretty darn good for an old one! There is a lot to like about this mill. The low backlash and low wear on the Gibbs are awesome.
Can't wait for the new back gear belt to arrive....... I would love to be using it and get a decision on which one to keep behind me.
Also bit the bullet and built up the broken pulley tooth with epoxy steel, and applied some Loktite 638 Retaining Compound to the pulley shaft since it was a little too loose (in my opinion), adjusted the pulley to run as true as possible, tightened up the nut, and then left it all to cure overnight.
It is sooooo hard to resist the temptation to install the old belt.....
It is sooooo hard to resist the temptation to install the old belt.....
I still don't have the backgear belt, but I decided to put the pulley and top housing on the motor today just to see how it will all work out.
Even though recessed the motor into the adapter plate by 3/8 of an inch such that the plate is only 1/8" at the motor, the key screw on the pulley ends up just beyond the end of the shaft. I already drilled and tapped for another key screw that will hold the pulley on, but I'm not thrilled. That's more than I bargained for. I could get the screw onto the end of the shaft by offsetting the pulleys a quarter inch, but that will end up wearing the belt and putting a lifting force on the spindle top section.
I had already decided to use some Loctite 638 Retaining Compound. But again, I am concerned that it won't be enough.
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So I'm brainstorming ideas. The best I can come up with myself is a pulley extension screwed to the motor end of the pulley, and a short motor shaft extension bolted to the end of the motor shaft. The idea is to increase the length of the joint between the two parts.
Even though recessed the motor into the adapter plate by 3/8 of an inch such that the plate is only 1/8" at the motor, the key screw on the pulley ends up just beyond the end of the shaft. I already drilled and tapped for another key screw that will hold the pulley on, but I'm not thrilled. That's more than I bargained for. I could get the screw onto the end of the shaft by offsetting the pulleys a quarter inch, but that will end up wearing the belt and putting a lifting force on the spindle top section.
I had already decided to use some Loctite 638 Retaining Compound. But again, I am concerned that it won't be enough.
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So I'm brainstorming ideas. The best I can come up with myself is a pulley extension screwed to the motor end of the pulley, and a short motor shaft extension bolted to the end of the motor shaft. The idea is to increase the length of the joint between the two parts.
Just had another thought. I'll try and find a 5 groove pulley with the same size large groove (to fit through the motor mount opening). Because such a pulley would be one piece and grab more of the motor shaft it would probably be ok and I wouldn't need the shaft extension. The smallest groove would not be used and could even be shortened if necessary.
Perhaps, this approach would allow me to use a standard key too.
Perhaps, this approach would allow me to use a standard key too.
Brent H
Ultra Member
@Susquatch : can you make a custom pulley?