Heavy duty Worm drive Saw Lubricant

[wrcsixeight]

I have a basic Makita direct drive 7 1/4 inch saw that took a spill off the sawhorse and bent the blade since I usually keep the annoying guard tucked up put of the way. A new blade revealed the shaft was wobbling, and while it still functions, it now spews wood chips right at my face, whichever side you try and use it from.

Since I been wanting a Better saw anyway, this was my excuse to relegate the Makita to masonry duty. I was torn between the magnesium base Hypoid Makita and the Mag 77 Skill worm drive for 10 bucks more.

The Makita, and all the other hypoids have a sealed gearbox, but the Skil has a fill cap, and their own "HD Worm Drive Saw lubricant. 8 fl oz for nearly 6 bucks.

Being a Bitoger, I naturally thought I could do better on the lubricant, but in the end said "helical inclined plane around a center axis it" and just bought the Skil brand lubricant along with the Mag 77.

I guess being a gear lube, it's got a lot of what? Moly?

The directions say if the oil is "extra dirty or thick", run it for a minute to warm it up to then hold upside down to drain the oil, fill it with kerosene, and run it for a minute and then refill it.

Also to change do this after the first 10 hours of use.

I have never had to remove the center part of saw blades to fit the diamond shape of the Skil arbor. What's the best way to do this? I'm putting this saw and a new 60 tooth Diablo blade to use first thing for a new client in the morning and don't want to putt around.

 

[spackard]

> I have never had to remove the center part of saw blades to fit the diamond shape of the Skil arbor. What's the best way to do this?

I used a hammer and a flat-nosed punch on that piece.

I bought the tube of Skil oil. I'm a homeowner and probably have a lifetime supply, if it doesn't leach out of the plastic tube and onto my shelf.

 

[another Todd]

I have a worm drive skill saw. I believe it is a 80w gear oil. I rarely use that saw anymore...it's too [censored] heavy. I bought a Miluakee 7 1/4 with the blade on the left for about $150 at Home Depot. I had no idea how slow the worm drive cut until I used this new saw. The new saw blade turns soo much faster it is increadable. Yeah, a worm drive has torque and can be forced through anything, but the circular saw actually cuts through it.

 

[Merkava_4]

I'm pretty sure that Skil worm drive lube is made from whale fat going by the
smell of it; plus, it won't dissolve in any kind of petroleum based solvent.

That diamond center on the blade can easily be removed by placing the blade on
a block of wood and striking the center with a pin punch. Set your punch just
inside the line of the diamond and strike it. You might have to move the punch
to a couple of different places inside the diamond before it pops out.

 

[morris]

i would use the same lube thats used in rear wheel drive trucks, or maybe heaver

 

[Tempest]

There was a thread on this on a woodworking forum a while ago and someone posted a link saying that 90wt gear oil is acceptable as replacement if the Skil oil isn't available.

Often times worm gear units have yellow metal components so using a very high quality automotive gear oil would be imperative to protect the yellow metal parts.

 

[wrcsixeight]

I've given this new worm drive Skil saw a heavy workout since its purchase, Cutting thin 8' strips out of 3/4" MDF from several 4x8 sheets.

It has gotten noticeably smoother and quieter as it has broken in.
Obviously a table/ panel saw capable of passing a full sheet would have been better, but the Skil with its taller footplate, run along an nice straight edge yielded impressive accuracy. I've had to do the same task with the Makita, and there were always blade marks in the cut pieces, no matter what quality Finish blade I used. Perhaps the Makita direct drive was faster, but it also wandered faster, and corrections caused the blade to bind and burn the material.

The Base of my direct drive Makita would have gone below the straight edge where the panel and straight edge sagged between the saw horses, and caused many a cursing fit, and time wasted=money lost.

Perhaps the Skil is a touch heavier than my direct drive Makita is, but I'm no lightweight either. Not a factor for me.

Honestly, I think the thing that sold me on the wormdrive Skil, was the fact that I could change the oil.


I think I have a problem

90 weight gear oil seems a bit thicker than the Skil brand lubricant, but then again I've only really used 75 or 80w90 oils in my diff so 'seems' is not very scientific.

I wound up prying the diamond center a little bit with a screwdriver while pushing down the other side, then switching, repeating, and it came out real clean.

Thanks,

 

[wrcsixeight]

Well, I changed the original year old oil today right after cutting a few 2x4's to warm it up. I figure it got at least 10 hours of continuous total use during the last year.

One project required cutting 6 inch deep 12 foot long arcs in very wet treated 2x12x12, and the blade was binding and I really needed the torque. A band saw with a big table would have been a better option, but one works with what one has. The saw got a real work out over the last year.

The oil came out somewhat foamy looking. I did not have any kerosene handy, but I refilled it with a sun warmed bottle of M1 TDT 5w 40 and ran it with no load for 30 seconds and dumped that in the pan, let it drain for 20 minutes, and once more for good measure. The mix kept coming out the same foaminess and color but turned dark brown after sitting a while.

The following photo is the first drain, no M1 rinse.

I positioned it so it could drain unmolested for nearly 5 hours and turned the blade by hand every so often and angled the saw all around to try and get out every last drop.

There were some real fine sparklies in the oil pan when held under sunlight.

This is a strong magnet wiped on a napkin after submerging it in the pan and moving it around for 30 seconds.

The following photo might give some indication of color and thickness of Skil's lubricant at about 75 degrees f. I will probably get 2 more oil changes out of this tube. No real strong smell, like gear oil.

And how can a Bitoger not at least attempt to get a shot through the fill hole to look at the internals?

A few months ago I used somebody elses' older much used Skil Saw. Man that thing was loud and gritty, but operationally fine. I asked him when he last changed the oil.

" Change the oil? What are you talking about? It's a freaking circular saw!"

I now have the magnet taped to the side of the clear container I put the used oil into. I'll update with photos of how much ferrous material sticks to the side of the container relatively soon if there is any interest.

I did have to cut through a 2x4 after the oil change, felt just as smooth as before.

 

[another Todd]

My worm drive is 25-30 years old. I changed the oil once about 15 years ago. Granted, I don't use it for a living, but they just don't need it changed very often, if ever.

 

[wrcsixeight]

I have not bothered taking a picture of the fuzz sticking on the inside of the container opposite the magnet, but the amount is significant. Especially considering there is just not very much oil in there.

I'm sure these saws can go a long time without a change, if it couldn't, well it would not have a good reputation.

The Skil worm drive lube is cheap. The change process is simple. I'm glad I changed it.