What's new
What's new

Regrind Heavy 10 bed

colinag

Plastic
Joined
Apr 1, 2009
Location
Woodstock On Canada
I need to get the bed of my Heavy 10 ground. I'm in S.W. Ontario. Does any one have any advice on where/who can do this work and how much could I expect to pay? Thanks to all. Colin.
 
They are expensive to re-grind because of the double-vees. I had three beds done at once and the SB10 cost the same as the other two together (and one was a HLV).

My guy first ground the underside ways of the saddle then ground the bed using the fresh-ground saddle ways as a gauge. The guy said that the saddle needed more grinding than the bed on my machine.

Obviously I can't help with a recommendation as I'm in the UK.
 
Message PM member cash, his company grinds ways.

I got a fair quote from him for our Heavy 10 SB a little while ago for the bed alone (3 v-ways and 1 flat) but the lathes still making chips so I'm not ready to pull the trigger on it yet. I'm planning on scraping it and the saddle together myself after it's ground.

From my research, grinding jobs like this start around $1000 and go up based on complexity, size, etc.
 
Thanks,johnoder, makes sense that the saddle would have more wear but the closer I get to the tailstock the tighter it gets so there must be some- a lot? of wear in the bed .A 1 inch bar in a 5C collet extended 2 inches turns .001 smaller at the collet face than at the 2inch out start of cut. Extend the bar 12 inches and use a steady rest and I get no taper. Am I right in suspecting bed wear?
 
Check that the bed is level. There's several threads on here on the topic (search for "Two Collar Test"), but in a nut-shell, if your bed has any twist to it, it will cut a taper. You can level the bed with a machinist level, but the fine tuning will be done by cutting stock, measuring it, and adjusting the bed.
 
Yep, if bed wear is the culprit it will almost invariably manifest as the workpiece getting LARGER toward the headstock.

You seem to have the opposite problem so suspect twist.
 
Thanks to all for your help with this problem. The bed is level according to my 12 in. Moore & Wright. Across the tops of the v-ways at either end or across the flats on top of two pieces of 5/8 drill rod I measure less than 0005 difference from absolute level. When I do the two collar test on a piece of 1 inch 12L14 held in 5C collet using fine feed and a light cut it turns .002 smaller at the head stock than it does 3 inches out. I removed the compound rest and put the level on top of the carriage and found the carriage sloped toward the front of the lathe in excess of .010 over the length of the level at the head stock and just about .008 at the tailstock This does not seem right but is interesting that the difference is about the same(.002). Is this the problem? If so how, do I fix it?
 
Thanks to all for your help with this problem. The bed is level according to my 12 in. Moore & Wright. Across the tops of the v-ways at either end or across the flats on top of two pieces of 5/8 drill rod I measure less than 0005 difference from absolute level. When I do the two collar test on a piece of 1 inch 12L14 held in 5C collet using fine feed and a light cut it turns .002 smaller at the head stock than it does 3 inches out. I removed the compound rest and put the level on top of the carriage and found the carriage sloped toward the front of the lathe in excess of .010 over the length of the level at the head stock and just about .008 at the tailstock This does not seem right but is interesting that the difference is about the same(.002). Is this the problem? If so how, do I fix it?

The odd reading youre seeing might be due to using a collet. If the machines done most of its work with the chuck on the wear in the bed will be 4-6" further out. Using a collet the saddle might riding up out of the hole producing your 'unusual taper for wear', skinny at the head stock end.
Be careful reading too much into level readings, unless youve some experience you can get caught out when moving things like saddles. Easy to check tho.
 
Cutting a 2 collar test as You said shows one error.
... the bed/saddle movement is wrong.

A workpiece grossly tilted in a collet should still be true after turning, and uniform.
Only an error in bed movement (x or z) should cause uneven sizes. Imho.
 
I have seen too many bunged up spindle tapers to rely on one being right without proving it.

Also, true story- bought a lathe cheap because owner couldn't get good results, lathe looked good to me so I bought it figuring if nothing else I could part it....the problem tuned out to be a 5MT collet adapter he was using...SB is not 5MT.:)
 
Thanks iwananew10k The spindle and 5C collet chuck consistently turn true round when checked with a dial indicator, so I don't think that's the problem. I will chuck up a 1.250 shaft in the 4 jaw and try another 2 collar test. Thanks to all. Back to the shop!
 
If the saddle is badly worn, it’s easy to check if you have a relatively unworn bed way area at the right end. Remove the tailstock and crank the saddle as far right as it will go and remain supported. Set up a dial indicator at each corner of the saddle and push down at the opposite end of the saddle as well as the opposite corner. If it’s swaybacked from wear, you’ll see the indicator jump.

Now imagine this convex saddle underside sitting down in the concave wear area of the bed ways. You can start to envision what the tool tip is doing as you traverse the carriage into and out of the low spot.
 








 
Back
Top