# Fray Milling Head With Broken Worm Gear



## NikolaiBorjeski (Wednesday at 10:52 PM)

A while back I got a Fray Model 1-1/2 mill with a Type 4 head. After removing the head to give it a clean up I noticed that the worm gear that's used to adjust the angle has many teeth broken off. Obviously it's been broken a few times in the past, and the previous owner clocked it at a different spot so the teeth would still engage. 

This still gives me close around 60 degrees of rotation with full tooth engagement, but I'm scared it might break off again and damage something more important. 

Does anyone have any advice on a repair? I don't have any hobbing experience or equipment, but I do have a lathe and I'm reasonably good with a tig welder.

From what I can gather it's different from a Bridgeport gear.


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## markba633csi (Wednesday at 11:08 PM)

You might download some catalogs from gear makers such as Boston gear and Martin gear and see if anything they have comes close. 
It looks to me like the gear is somewhat inadequate for the load requirements- if you can retrofit anything larger in there I would try
Of course that means changing the worm shaft also- probably a major engineering exercise
-M


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## OTmachine (Wednesday at 11:16 PM)

You could weld up the damaged teeth, turn down the major diameter, grind a flycutting tool to match the remaining teeth’s profile and use the remaining teeth as an indexing mechanism to recut the teeth.  Been there before.


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## NikolaiBorjeski (Wednesday at 11:38 PM)

I'm not sure if it failed due to bad design or abuse. Perhaps this gear wasn't treated properly. 

The worm shaft has a Boston number on it, so it's a good chance the gear is a Boston as well, even though I couldn't see numbers. 

I didn't think about using the teeth themselves to index on, that might be possible, though tricky since they're helical.


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## ErichKeane (Wednesday at 11:51 PM)

A helical gear is one of the more difficult ones to make yourself, so making your own is probably the key.

I'd suggest doing 2 things: 1- count the number of teeth on the gear.  2- look up the boston gear part # on the worm.

You can use the info from looking up the worm for PA/DP/etc.  THEN, just grab a PA/DP gear that matches wtih the right amount of teeth.  The mount holes are likely necessary to cut afterwards, but that seems like the easiest way to me.


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## Nutfarmer (Thursday at 1:17 AM)

You can still set tram with out the gear. Just set the bolts with a little more drag.  Not easy but it will work.


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## NikolaiBorjeski (Thursday at 9:30 AM)

Seems like looking through the Boston catalogue worked! Appears to be this one, also available from McMaster-Carr. Just needs to have the hub machined off and 4 holes drilled in it, that I'm confident in doing. Now just to get it to Canada...


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## ErichKeane (Thursday at 9:41 AM)

That definitely looks a lot like it!  Good job!  

From looking at that, Martin Gear has that under `W1230` as their part number if I'm reading this right.  it is roughly the same price as Mcmaster everywhere.  

Here is a company in Canada that lists it, and seems to have B&M places.  Unofrtunately it appears the closet to you is in Sudbury ON (~$375 KM) https://www.sourceatlantic.ca/Product/W1230 ...

That said, that probably means you can order from them?  


That said, according to Martin, they have 3 locations in Canada, including 2 in Ontario.  1 is Mississauga, and the other is in Ayr (roughly a 40 km drive!).


			https://www.martinsprocket.com/mobile/Locations/Canada.aspx
		


Might be worth giving them a call to see if there is any way for you to pick one up/order one directly from them?


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## markba633csi (Thursday at 11:26 AM)

One of the benefits of having a US made machine! 
Interestingly, I have a 80s Taiwan-made bandsaw that also uses Boston worm gears
Some things are easier to buy than make even overseas


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## benmychree (Thursday at 12:36 PM)

I have that same mill in my shop, but without the power feed; what is the flange bearing unit above the vertical ways for?


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## NikolaiBorjeski (Thursday at 1:46 PM)

Called Martin in Ayr, while very helpful they aren't able to sell to the public, and for some reason shipping from Sudbury was $50. Ended up ordering the Boston part from our local Fastenal that we get hardware through for work, should be here in a few days, super easy! 

This machine has half of a power feed unit. It has the gearbox but no motor, previous owner used a cordless drill, I plan on fitting a modern power feed unit with electronic stops and speed adjustment. That bearing flange above the ways is actually a horizontal spindle! Has its own dedicated motor and everything. Unfortunately doesn't use the same tooling so its not super useful to me but cool nonetheless.


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## markba633csi (Thursday at 11:15 PM)

Frays are nice- I would buy one.  Very versatile machine


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