MC100 tailstock woes

**thefixer** · 13th April 2009, 04:26 PM

I guess anyone with the MC1100 and MC900 lathes has the same problem with too much sideways movement in the tailstock. This can be a real pain when reverse chucking or even worse turning a pen. The problem is a result of the lathe bed and tailstock being made from a casting and then not being precision milled to fit each other. You get what you pay for I suppose.<o></o>
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Here's how I fixed the the problem.<o></o>
Pic 1 shows the underside of the tail stock. Both of the tabs that slide between the rails of the bed are different sizes and both of them are narrower than the space between the rails. Hence the sideways movement. Pic 2 shows the gap between the tailstock and the bed. Almost 1mm gap.
Attachment 102345 Attachment 102346
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Pics 3 and 4 were taken from directly above the lathe and you can see how much movement there was from left to right.
Attachment 102347 Attachment 102348
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The first issue to overcome was the lathe bed. The space between rails was not consistent in size, so I hand filed the full length of the bed on both sides using a length of steel previously filed to 38.3 mm as a template. Pic 5. I used a large flat file along its length to achieve this. Roughly 5 or 6 hours filing.<o></o>
Pic 6 shows the bed pretty close to perfectly parallel and consistent in spacing.
Attachment 102349 Attachment 102350
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I Then cut two pieces of 5 mm thick steel plate in the shape shown in Pics 7 an 8 drilled and bolted to the front and back of the tailstock. I then carefully filed them to fit between the bed nice and snug. All the time checking to make sure I was not getting off line.
Attachment 102351 Attachment 102352
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The end result shows the effort was justified. Pic 9. I also put a jacobs chuck in the headstock and another in the tailstock and length of steel rod in each chuck so I could fine tune the alignment over the length of the bed. There is now no sideways movement in the tailstock at all and the alignment is spot on.
Attachment 102353
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You may ask, why go to so much effort and time when I could just get a more expensive lathe that is precision made? Hmm, Time I have, $$$ I don't. Besides, I get a real buzz when it all works out the better.<o></o>
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Cheers<o></o>
Shorty<o></o>
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**DJ’s Timber** · 13th April 2009, 04:35 PM

Good result

**pommyphil** · 13th April 2009, 04:50 PM

Great fix. I'll put it on my list.

**ss_11000** · 13th April 2009, 05:19 PM

**hughie** · 13th April 2009, 05:28 PM

You may ask, why go to so much effort and time when I could just get a more expensive lathe that is precision made? Hmm, Time I have, $$$ I don't. Besides, I get a real buzz when it all works out the better.<o></o>
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I can relate to that

good fix

mines not too bad, the headstock was the culprit for me.

**artme** · 13th April 2009, 05:35 PM

No wonder you are "the fixer", and a very patient one at that!

Great result!!

**new_guy90** · 13th April 2009, 06:07 PM

now i want a Vicmarc even more

i suppose you get what you pay for but not even machining the keys is a bad sign, but its good to know that you dont have to go and get it re-machined. im forever adjusting my lathe centers but i have a different problem, mine is a large pipe that just ##### me off but its great when i get it right

how exactly did you get it right over the whole bed?

thanks for showing

Patrick

**thefixer** · 13th April 2009, 06:53 PM

Originally Posted by new_guy90

how exactly did you get it right over the whole bed?

thanks for showing

Patrick

File and check Patrick, File and check. For bloody hours

Cheers
Shorty

**orificiam** · 13th April 2009, 09:01 PM

Well Done Shorty.

Cheers Tony.

**Ozkaban** · 13th April 2009, 09:14 PM

Wow. I have exactly the same issue with my MC1100.

You're a very patient man! I don't know if I could file the bed for a whole day. How are your forearms holding up?

Very impressed with the result though. Maybe would be worth doing, but I've just noticed some slop in the headstock bearings, so they're next. And then the belt... and then this fix..

anyone selling a Nova 1624?

Cheers,
Dave

**thefixer** · 13th April 2009, 10:31 PM

Originally Posted by Ozkaban

.

You're a very patient man! I don't know if I could file the bed for a whole day. How are your forearms holding up?

Cheers,
Dave

Patience is a virtue Dave. Now if I can just get that through to that short tempered, impatient 17 year old son of mine

then one day he will be a great turner.

Cheers
Shorty

**Skew ChiDAMN!!** · 14th April 2009, 02:19 AM

Very nicely done! Wish I'd approached it that way... maybe ovalling the holes in the plates out a bit to allow for some fine adjustment.

Instead, I filed back the sides of the tangs to expose fresh metal and got a mate to run a bead of braizing on each side. Which I then had to painstakingly file back to make a fit. (And after finally getting a nice fit at the headstock end, discovered that - like yours - the ways weren't quite parallel and it bound up 6" from the tail-stock end...

)

I really, really wish I'd thought of your method!

**thefixer** · 14th April 2009, 07:52 AM

[quote=Skew ChiDAMN!!;936350]Very nicely done! Wish I'd approached it that way... maybe ovalling the holes in the plates out a bit to allow for some fine adjustment.

I already did that. I don't have that much faith in my engineering skills to rely soley on getting it exactly perfect. Some adjustment was bound to be required after completion.

Cheers
Shorty

**arose62** · 14th April 2009, 08:15 AM

I have this problem too, and am still thinking through my solution:

at the moment I'm consdering adding a large circle of metal to the front and back of the tailstock, but mounting them with an off-centre bolt so that they act like cams, and can thus be adjusted, rather than having to file to get the fit right (because I couldn't think how to guarantee that I achieved alignment with the ways).

I'm also thinking about how to get the tailstock aligned with the ways - surely there's some clever method involving one of those cheap keyring laser pointers...

Cheers,
Andrew

**Grumpy John** · 14th April 2009, 08:20 AM

Originally Posted by thefixer

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<O></O>
You may ask, why go to so much effort and time when I could just get a more expensive lathe that is precision made? Hmm, Time I have, $$$ I don't. Besides, I get a real buzz when it all works out the better.<O></O>
<O></O>
Cheers<O></O>
Shorty<O></O>
<O>
</O>

You wouldn't be a fitter & turner by any chance would you Shorty

. In any case you'd make a great machine tool service man

. The next thing to do is to hand scrape the top of the bed to get to perfectly flat, that should only take about 3 - 4 hours

.

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