8" Bison 4 Jaw Combination Chuck

[Alan H.]

Brad, thanks for the feedback. Yes, that chuck is a chunk of steel to say the least. I am glad that I built the wooden sled for it so it is easier to handle and to make it a bit easier to heft it around.

For me the chuck giving me the ability to take pieces out of it and get them back in with ease and some accuracy is outstanding. The finish on the chuck is outstanding and the scroll is smooth as glass as well as each individual jaw carrier. I am sure that I am going to be using it often now.

As you pointed out, Mark's chuck key design is quite helpful and a big plus to have to go along with the chuck. Here's my build of his concept. I really liked Mark's idea for the magnet embedded in the end to help hold it on there and replicated that as well. I made mine out of 1144 Extra Strength which was a bit of mistake for knurling. The 1144 ES is a bit too hard to get a good knurl and I also discovered that my knurling charts were off due to not considering the transverse pitch on 30 degree diagonal knurls. Meanwhile they are okay as is and quite functional and good to go.

Thanks to Mark for always being willing to share and help others. Paco is from the same cloth as well. Folks like these two plus all the others makes this forum a great place.

 

[Alan H.]

I gather that this chuck was on-sale and that sale has ended. With that said, would someone please post what they paid for one of these combo chucks?
I am not really in the market because the pricing that I see is about 3/4ths the price that I paid for the entire lathe but would like to have a price to compare future offerings too.

thanks

Mike

PM sent

 

[Reeltor]

PM sent

I have my answer, thanks

 

[bss1]

Nice work on the wrenches. The drawing looks excellent as well. I wish I had those skills and patience. I usually scratch down a few measurements and wing it. I must be lucky. I have yet to use the tables for knurling and for the most part come out ok.

 

[Alan H.]

Nice job on the knurls! What material is that?

Thanks for the compliment on the drawing but it ain't much. I am hoping to renew my skills with some 3D cad and eliminate all these sketches. They take too much time.

 

[bss1]

Thanks Alan, It’s just some O1 drill rod that I used for the chuck keys. I had a 3’ section I was working with so I used the spider to support it and did most of the lathe work and knurling before pulling it and taking it over to the Ellis to part off. I did both wrenches like that, then put them in the collet block to mill the end square. After that I removed the monster Bison 4-jaw and used the collet chuck to finish and counter bore the backside. I found the collet doesn’t seem to smash the finished knurling as bad as a regular chuck jaw. I’m sure there is a more efficient job sequence. I usually won’t do the knurling step with the collet chuck as it doesn’t get a good enough grip on the stock for the amount of tension I use to cinch down on the knurling Tool.

I seem to get the same results with brass, bronze , or aluminum. I have even done some smaller 1/4” 316 SS. I’m sure I just jinxed myself and will never get my knurler to work again...


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[Firestopper]

I received mine last week. First impression was wow, this thing is big and heavy. Hoisting it up for the first time left me wishing I was wearing some steel toe boots!

The chuck has a very nice finish and looks very well machined. I also bought the back plate from MSC. I mounted it bare on the spindle and it seemed to have no detectable run-out. I then installed the plate on the chuck. The fit seemed perfect, again very well machined.

I used the chuck to make the keys that Mark and Paco have.

View attachment 242554

I quickly found that they are a necessity to work with this chuck. The stock key is a PITA to adjust the chuck, at least on a 1340GT. There is just not much room to spare with the length of the key. The design of Marks keys was excellent and greatly enhanced the dialing in process.

My take on this chuck is that it gives you the accuracy of a standard 4-jaw, but much easier to dial in and re-tru if you have to remove the work piece. While I rarely use my regular 4-jaw because of the time it takes to dial in, I would be more inclined to use this one due to the ease of adjustment.

My only issue is the size and weight. I tend to use my collet chuck and a 5” 3-jaw the most as it is so easy to handle them and switch out when necessary. For me, this chuck is so substantial, it leaves me less inclined to switch it out for one of the other chucks that could work better for the application at hand. With that said the size issue is subjective and more reflective of the personal preferences of the user. I think a 6” version of this chuck (if they make one) would be a little better suited for me and the PM1340. Maybe I just need to go to the gym some more. It is a very nice chuck, and for the bargain price paid, I am happy to have it as part of the growing inventory of attachments.

Brad, thanks for the feedback. Yes, that chuck is a chunk of steel to say the least. I am glad that I built the wooden sled for it so it is easier to handle and to make it a bit easier to heft it around.

For me the chuck giving me the ability to take pieces out of it and get them back in with ease and some accuracy is outstanding. The finish on the chuck is outstanding and the scroll is smooth as glass as well as each individual jaw carrier. I am sure that I am going to be using it often now.

As you pointed out, Mark's chuck key design is quite helpful and a big plus to have to go along with the chuck. Here's my build of his concept. I really liked Mark's idea for the magnet embedded in the end to help hold it on there and replicated that as well. I made mine out of 1144 Extra Strength which was a bit of mistake for knurling. The 1144 ES is a bit too hard to get a good knurl and I also discovered that my knurling charts were off due to not considering the transverse pitch on 30 degree diagonal knurls. Meanwhile they are okay as is and quite functional and good to go.

Thanks to Mark for always being willing to share and help others. Paco is from the same cloth as well. Folks like these two plus all the others makes this forum a great place.

View attachment 242571 View attachment 242572

Those mini "T" turned out fantastic guys!
It'll make things quicker to dial in. Don't forget to pull them off (back side out of sight, out of mind) immediately after dialing in. So cool to see results following discussion. Too many times we talk about things and never "get er done", not here at HM!
Again, nice work fellas.
Turn and Burn!
Paco

 

[Alan H.]

I have been using this chuck now for the past few days and I can imagine that I will never use my older 4 jaw again plus my three jaw may get very little use as well. I am thinking this and my 5C collet chuck will be my "go to's" here forward.

This chuck is outstanding. It let me flip a piece and it was close enough to turn it within a half. You cannot see the line on this piece of 2.5" chrome moly. Another positive is that it has finally stopped throwing grease!

 

[rzbill]

Mark and Paco, how do you gents handle this little chuck? It is a bit heavy isn't it? Did you build a sled to help mount it or do you simply mule it on there?

 

[Firestopper]

I used my Bison comb chuck today as well on some delrin. Had to flip it for second counterboring operation. The reamed through hole remained absolutely dead nuts X2. Gotta love them chucks