Sherline Boring Head Improvements

[EricB]

I had read in other posts here that Sherline's boring head is not a very good tool. I've used mine a few times now and I can say you can get good results with it, but it needs help out of the box.

The first two holes I bored with mine I did get good results, probably from my ignorance, but I noticed I could rock the tool around where the top and bottom of the head clamp together. Also with the clamp screw tight there was a visible gap between the top and bottom parts of the head. Not knowing any better I figured that's just the way it's designed.



The next hole I tried I couldn't get anything to go right, so I decided to figure out what was going on.

What I found was the hardened steel pin that the end of the adjusting screw bears upon, that Sherline calls the Gear Drive Pin, was making contact with the bottom half of the head when the clamp screw was tightened. This was why I could rock the end of the tool.



Grinding the tip of the pin to provide some clearance eliminated the rocking and the visible gap was gone, but created another problem. Now when I ran the adjustment screw through its range the bottom of the head would suddenly loosen after a few turns. This problem was solved by filing the edges of the dovetails on the top part of the head (two arrows from the left), and deburring every other machined edge.



Now the cutting tool is held solid and the adjustment screw takes even pressure throughout its range.

Hope you find this helpful.

Eric

 

[mikey]

The Sherline boring head is just okay. It gets the job done but the term "robust" cannot be used in the same sentence with this head. For tiny bores, it works but when getting to the extremes of its range it is very not good. I used one for a long time and know this head quite well so trust me when I tell you that it is nowhere near the capability or accuracy of a Criterion S-1-1/2 boring head.

Glad you got yours sorted and I in no way mean to disparage your efforts or the results and usefulness of your post. Job well done!

 

[EricB]

Mikey,

Don't take this the wrong way, but your testimonial about the accuracy or capability of your Criterion tool is not relevant for those of us who use the Sherline tool.

Eric

 

[mikey]

Understood.

 

[Karl A]

Eric,
I don't yet have a boring head for my Sherline 5400. The Sherline model with Improvements described in your post may have to do for me, at lea for a while -- being that the model that Mike recommends appears to be rare or expensive. I saw one for sale on Ebay for $999.
Thank you for sharing the improvements.
Karl

 

[Buffalo21]

I’ve been looking for a small boring bar head, for a while. I’m not looking for a high buck items, or one that is going to be run constantly, I’m thinking 4-5 times a year. I realize it may not be perfect, but is it workable, under the parameters I stated??

 

[EricB]

I’ve been looking for a small boring bar head, for a while. I’m not looking for a high buck items, or one that is going to be run constantly, I’m thinking 4-5 times a year. I realize it may not be perfect, but is it workable, under the parameters I stated??

I just used mine again today. After the mods mentioned above I think it's a good tool considering the size work it's designed to do. Just stay within its envelope and keep the chips out of the way. So far it's the only Sherline accessory I've purchased that didn't work right out of the box.

Eric

 

[Buffalo21]

Eric,

thank you for your response, I was talking to a friend about this last night, he has a small Taig boring head, he bought a few years ago and has used once or twice, he said he would drop it off to see if it would be workable for me. I not sure how much difference there is between the Taig and the Sherline, the Taig has a 3/8” straight shaft for collet mounting, similar to the Sherline 3054S, the MT#1 tapered mounting is of no use to me. I’ll try it and see if of any use.

Again, thank you

 

[EricB]

Eric,

thank you for your response, I was talking to a friend about this last night, he has a small Taig boring head, he bought a few years ago and has used once or twice, he said he would drop it off to see if it would be workable for me. I not sure how much difference there is between the Taig and the Sherline, the Taig has a 3/8” straight shaft for collet mounting, similar to the Sherline 3054S, the MT#1 tapered mounting is of no use to me. I’ll try it and see if of any use.

Again, thank you

I believe the Taig head uses two set screws to adjust the depth of cut, and you would need a separate indicator to know how much adjustment you get. Other than that they are similar to the Sherline tool.

Eric

 

[EricB]

Just a little update. I finally found a need to bore a "large" hole with my modified boring head. The part will eventually be the frame for a model steam engine. The target bore was 1.063". I overshot that by 0.015" but I was measuring with a ruler instead of the proper tools. It took 4 passes at the final size for it to stop making chips.



Measured with the proper tools I have a round bore with no taper. The finish came out nice too. So I guess it is possible to get good results with this boring head.

Eric