How To Split a Sprocket to fit over a Shaft

[@bigdave6447]

On a motorcycle the sprockets wear from adjusting the chain! When you keep adjusting the chain you change the pitch and wear out the teeth. Chain gets loose ,replace chain. Sprockets will last forever,or close to it!

[@jimc4731]

It looks like the teeth are induction hardened, doesn’t that drastically shorten your saw blade life? Keep up the good work! JIM ❤

[@richardgreen7811]

That was pretty cool. When you began drilling the shank of the sprocket I had no idea where you were going. Also, I had no idea your Johnson was that big.

[@BrucePierson]

That's an interesting concept to simplify the sprocket replacement and save a lot of work doing it the conventional way.

[@TopperMachineLLC]

This customer has been doing it for 30 years. They just got so busy that they farmed it out. Was a great learning experience for me and for everyone on here.

[@jackdawg4579]

Ah, I assumed you were going to crack them like how they do big ends, not cut them. Do they need to shim to keep it even / make up for the material lost in the sawing - when tightening them in place?

[@mhagnew]

I thought so at first but no, the bored hole clamped on the shaft will keep the OD of the sprocket the same. When the two halves are bolted back together, the pitch between the teeth on either side of the cut should remain the same. I suppose you could have one gap tighter on one side if you tightened one of the cap screws way more than the other. I'd check the root on either side with a piece of stock the diameter of the chain roller just to be sure.

[@isaacdamm9142]

That's pretty slick! Thanks for showing that.

[@sanjaysami4315]

Does the loss of material from the kerf of the blade cause a problem ?

[@charleskutrufis9612]

Thank You

[@hobsonrutland4861]

Do you account for the kerf of the saw blade when machining? Or how do you work around it?

[@josephleister9198]

That's very clever.....thanks

[@mrspencerls]

Great idea. Thanks for sharing

[@ZaneFirebrand]

Can you post pictures of the coolant system on your Johnson bandsaw we have the same saw and the end next to the blade that pours coolant on the sawblade but I'm not sure where the coolant pump is. I would like to get the coolant running again.

[@TopperMachineLLC]

There is a large ring gear inside the drive wheel that drives the pump. Very simple. What I would recommend to you if you don't have all the parts is an electric pump. I put one on a power hacksaw years ago and it worked better than the one on the Johnson handsaw.

[@SPH56]

New to your channel and really enjoy your explanations. Though most likely not possible, it still would be interesting to see the final install of the sprocket that justified the split.

[@TopperMachineLLC]

Thanks for watching. So, I can't show the application, but it's a long shaft inside a machine. It would require about 20 hours to remove. This is what we came up with to simplify the replacement. Shaft is actually about 16 feet long and has 10 sprockets on it.

[@alanm3438]

Great idea!!!!!

[@guillermocarrillo3959]

Doesn’t the shaft hole become smaller by the amount the saw has removed? Seems that if you remove metal the hole will narrow itself and no longer be the same round diameter.

[@timengleman]

When the two parts are clamped together on the shaft, the shaft itself makes the bore of the sprocket conform to the right size. When a tooth in the sprocket half without the keyway is carrying the chain load, some odd and variable loads must be taken throught the cap screws. Not applicable where full sprocket rating is needed or where there is an uneven number of teeth (unless you can somehow cut two split lines. In any case, there may be some unusual chain roller wear.

[@buckshot75two]

Let me this straight, If the bore of the sprocket is the same as the shaft OD, cutting a sawblade thickness out of the sprocket won't matter as long as the tooth pitch is not affected. You could make metal gasket to fill that space, by using 1/2 of the split sprocket as a pattern. A plasma cutter would be great for cutting the gaskets from semi-hardened sheet metal. Soft metal would crush when the bolts were tighteded.

[@joell439]

Very interesting 👍😎👍

[@curtisharlan9230]

That is cool

[@joewest1972]

Good videos but focus and lighting need attention fyi

[@deakindog7525]

not to criticize but people sometimes convey what they know in their mind but it doesn't translate well to others. as in the bottom of the tooth is different to me than to you. i would say the root instead. to me the bottom of the tooth is somewhere below the pointy part.

[@TopperMachineLLC]

Thanks. I'm trying to keep the terminology simple so everyone can understand. But then again, it can be confusing for others.

[@jetegtmeier71]

so your going to feed your Johnson nice an slow and split it right open.... Sounds great ;)

[@mikeking7470]

You are losing metal on the bore, probably non-critical for low RPM, I could see milling away half of each of two sprockets to make one that had a full circumference.