Collet Blocks

These look good, shame about the price.

**LINK**

That link throws up a warning about a Trojan on my PC.

Brian

May not be so much, converts to about £45.00 in sterling? So if you really want one...

Rod

Interesting. 12 sides so it can replace both 4 and 6 sided blocks.

However narrower sides mean that you'd need fairly tall vice jaws to hold it properly. Would the common Vertex style and Kurt acculock knock-offs be deep enough?

Although I have had both 4 and 6 sided 5C blocks for many years they rarely get used due to the faff involved in setting them back into exactly the same longitudinal position after each part turn shift. Close is pretty easy but avoiding that annoying 1 to 10 thou step left when you don't quite get it right is another matter.

So I usually reach for the spindexer. The blocks tend to be reserved for when the degree disk gets in the way, Pity you can't easily reverse the spindle.

As the ER collet is front locking it would seem relatively easy to make an indexing horizontal / vertical carrier along the lines of those supplied for 5C collets. In principle the indexer could go where that incredibly irritating pin in hole draw up closure nut goes on the 5C type. In practical something designed from scratch would be more elegant.

A H/V ER collet carrier device like that would cover almost all of my spindexer and collet block work with the added advantage of easy vertical mounting. Just have to break out the dividing head or rotary table a bit more often for the few times when 12 positions wasn't enough but perm another number from 360 would have been.

Clive

Edited By Clive Foster on 02/11/2020 18:22:31

Edited By Clive Foster on 02/11/2020 18:22:52

Clive, don't you have any vice stops

As for a spin indexer I use the Stevenson one with it's 5C to ER32 converter and special nut. Or you can just put a standard 5C to ER32 converter into any 5C tooling

I have seen a conversion of a Spindexer where the disc was placed at the other end. May be worth a google if you’re interested?

Jason

The VJ400 vices I use don't really suit simple vice stops. Also jaw overhang from the sides of the base is 3/4" or so which is perhaps more than ideal when you need to get the block re-seated really flat. Something like your bottom picture would work OK but I just don't use the collet blocks enough. A flat magnet about 2 x 1 x 3/16 inches does similar duties well enough when needed.

Usual chicken and egg. If I needed such something suitably engineered would get done PDQ. But the need hasn't really been there. Better use of the effort to make mounting the spindexer quick and easy. Having a 5C mount three jaw makes it much more useful too.

49" of Bridgeport table to play with means a separate rod'n block system generally suits me better. But I'm home shop guy, not model maker, who makes "stuff" for folk and for my own vehicle modification work. Usual rule is interesting jobs only.

Exercise bike broken shaft quick fix and mating the wrong speedo to the wrong bracket with the also wrong rubber shroud (three wrongs had to make a write) for a motorcycle were this weekends games. Ongoing fun includes how to undo a near terminal bodge on the string side metalwork of an 1880s Erard grand piano and produce a batch of totally unobtanium, non-standardium wing headed screws for it.

Vic

Yup. Seen that and thought it a bit more work than "might be nice" warranted. If I need it it will happen. Fast!

Clive

Well worth dismantling old computer hard drives as a means of deleting the data.
They yield a couple of powerful curved magnets, which can sometimes get in better than straight ones.
The platters also make reasonable surface coated mirrors, rather than looking through the glass at an angle on conventional mirrors.
Bill

Yes agreed Clive. I’d like to convert my spindexer as well but it is a bit too much of a faff at the moment.

If anyone on here’s done one though I’d be keen to hear their thoughts.

Edited By Vic on 03/11/2020 11:27:54

I don't have any collet blocks but I have heard it said that a hex block can be clamped on the flats or the corners to give 90° increments.

Here is a pretty comprehensive video showing the spindexer mod: **LINK**

William.

The down side of Clamping a hex block on corners and flats is that you have to alter the Z height rather than just take 4 cuts at the same height if machining a square end on something.

I'd think about relocating the lock screw on an indexer if swapping ends then it keeps your pinkies away from the tool so you can index without having to stop the spindle.

I machined the bottom, sides and faces of my spin indexer quite soon after I got it and added thrust bearings as well. Didn't bother with the covers or o rings as I don't have a grinder that I use it on. I also didn't swap the ends round. Like Clive I have a 5C mount chuck to use with it as well. To do the first operation I set the bore up to the spindle axis and made sure the front face was square to the spindle rotation and machined the base using the front face as the datum. You can see one of the thrust bearings in this picture from 2017.

Martin C

I machined the sides of the base and cut clamping slots on mine. I did this relative to the bore of the spindexer as suggested on one of the engineering sites by “Bogstandard”. I didn’t touch the base as it seemed to be ok. I have seen a video of a guy machining the base without any reference to the bore at all so who knows how accurate it is when set up on his mill?

Edit: This was the post.

http://www.modelenginemaker.com/index.php/topic,1427.0.html?PHPSESSID=7ii2iqhq6fedob4q1tutacr490

Edited By Vic on 03/11/2020 17:48:42

Be careful when holding something that is short relative to the vise jaw width at one end of the jaws. Many types of vise will require an identical width block at the other end to stop their jaws tilting.

The trouble with buying from down under is that the postage can be even higher than from the USA.

Edited By old mart on 03/11/2020 20:00:31