Myford Bed and Saddle Article 01-004: Service and Repair Guide (EN)

12/01/11 08:31 Myford Bed and Saddle article 01-004 Wednesday, January 12, 2011 8:31:21 AM News Comment Diary Dates Archive Datasheets Tools From Myford Technical Support 01/004 Dec 2010 Better Beds and Saddles. We explain the changes to the Myford bed and saddle re- conditioning service The full service is very popular and we have no plans to stop it, however we ceased the Bed only regrind service at the beginning of October. We have found that the lower cost option of regrinding the bed alone has unwittingly misled some buyers inspecting pre-owned Myford Lathes offered by used equipment suppliers.

To many a smooth, clean lathe bed is a sign that the lathe has been cared for and not subjected to heavy wear. This, as any engineer will know, is not necessarily the case, a bed regrind can hide a lot of wear indeed. Whilst superficially making things look better it can actually worsen the lathe’s standards of accuracy. The nominal thickness of the shears (bedways) on a finished new Myford bed is approximately 0.5” (12.70mm). The maximum that may be removed from the top of the bed is 0.025” (0.635mm) before complications occur in aligning the apron with the rack and leadscrew.

The bed that didn’t make it During a Myford factory bed and saddle regrind metal removal is kept to a minimum, however it may be necessary to reduce the thickness of the shears between 0.005 (0.127mm) and 0.010 (0.254mm) to get back to a sound top surface. In theory it’s possible to regrind a bed between 2 and 5 times. Indeed, as our records show, this has been done for a number of customer owned lathes. This involved an early Super 7 bed which was originally despatched, as a new lathe, from our works in late 1953. It was returned to us in 2007, after 50 odd years of continuous use. In came the bed with saddle and all associated parts.

The owner earnestly requested a bed and saddle regrind but unfortunately we were unable to help. What caused the problem with this particular request was a dent in the bed approximately 0.075” (1.9050mm) deep and, of course, outside of the limits. All was not lost we were able to source a pre-owned bed which we reground and matched to the existing saddle. This lathe is still performing well today. At Myford we have long considered it essential that if a bed regrind is to be carried out then the saddle must be also be ground and the fast edge scraped to give correct alignment.

A worn saddle on a newly ground bed offers poor contact and it is not practical to improve this to the required standard simply by scraping. Many Bed and Saddle regrinds, and re-regrinds are carried out every year and nearly all fall within limits. The saddle also has its limits inasmuch as lubrication can become ineffective when the oil grooves become narrowed by heavy wear of the slide faces, something to be aware of if regrinding yourself. To complete these grinding operations the various gib strips are re-worked to remove the effects of wear and the front and rear strips stepped to compensate for the reduction in thickness of the bed shears.

We will no longer take orders for regrinding beds only - believing it to be in the best interests of Myford owners and future Myford owners. Two points are clear, there are times when wear is beyond recovery – and one bad component doesn’t write off a lathe provided the work of repair is correctly carried out and inspected to reaffirm original standards have been restored. Every regrind of bed and saddle we undertake is thoroughly checked and inspected at refit. We offer a certificate to that effect and hold a record of all Serial Numbers, dates and reports should future owners wish to check the history of their lathes with us.

Full details including scheduled dates for this service Click here . RELATED ARTICLES .......................................... MYFORD WEBSITES .......................................... • Bed & Saddle Schedule www.myford.com Page 1 sur 2 http://www.myford.com/meu/MEU_Issue_01/article_01-004.html

Стр. 1

12/01/11 08:38 Follow a Myford Lathe Rebuild - Myford Factory Rebuilds Page 1 sur 13 http://myford-rebuilds.com/epages/eshop433741.sf/en_GB/?ObjectPath=/Shops/eshop433741/Categories/Follow_a_Myford_Lathe_Rebuild Home page Myford Lathes Myford Accessories Bed and Saddle History of Lathes Myford Vacancies Home page Myford Lathes Myford Accessories Bed and Saddle History of Lathes Myford Vacancies About us Contact Categories Myford Lathes Myford Accessories Bed and Saddle History of Lathes Myford Vacancies About us Product search Search term Home page Follow a Myford Lathe Rebuild Follow a Myford Lathe Rebuild Reproduced by kind permission of Model Engineers’ Workshop and Geoff Sheppard New Lathes For Old From its first appearance in the late 1940s, the Myford Series 7 lathe has been with the owners of home workshops.

The Company now operates a factory re- conditioning service and also offers re-worked machines for sale. Geoff Shepp given the freedom to tour the works with notebook and camera to see what wa involved in restoring a particularly roughly used example to a state where it wo meet new production acceptance standards. When the Myford ML7 lathe appeared, not long after the end of World War II, it set new standards fo equipment for the model engineer’s workshop. It also found a ready application in industry, particularl instrument work and similar light engineering tasks.

Over subsequent years, many thousands of them been produced and there has been a steady product development programme, with many refinement as well as the major upgrades introduced in the Super 7 and now the Connoisseur. Indications are that, of all the Series 7 lathes produced, a very high proportion still exists, relatively fe having been totally scrapped. The condition of these survivors varies immensely. Those installed in p workshops are often cosseted as prized possessions, many having seen very little use. Indeed, one o volunteered the information that he has a very early model that has never been used.

Conversely, oth had a very hard life, particularly when they have had to earn their keep in industry. A particularly hars environment, where the machines often suffered more misuse than use, was the school workshop, w machines sometimes suffered damage as a result of practical ‘jokes’. I have had recent personal exp two lathes recovered from these latter environments, the condition of which made me wince when I e the mis-treatment they must have received. Myford Limited have always operated an excellent spares support service, with, in my experience, rep components arriving within a few days of placing an order.

They have also offered a bed regrinding s restoring worn slideways and the mating saddle surfaces to standards, which match those of the new Over recent years this has been extended to the point where it is possible to have a well-used machi reworked so that it meets the acceptance standards required of a new production unit. The logical de has been to offer factory-reconditioned machines, supported by a warranty similar to that provided wi lathe. Myford are now prepared to buy back lathes, restore them and then list them at prices which re standard and age of the model and the level of equipment with which it is offered.

popular ard was s uld r y for have s added, w of them rivate wner has ers have h here erience of nvisaged lacement ervice, machine. ne velopment th a new flect the Shopping basket Your shopping basket is empty. Sign in User name Password Sign in Forgot your password? Register For the latest news visit our Myford Factory Rebuilds Blog Contact our Sales Department Categories Shopping basket Sign in Search term

Стр. 2

12/01/11 08:38 Follow a Myford Lathe Rebuild - Myford Factory Rebuilds Page 2 sur 13 http://myford-rebuilds.com/epages/eshop433741.sf/en_GB/?ObjectPath=/Shops/eshop433741/Categories/Follow_a_Myford_Lathe_Rebuild Photo 1 The Myford Super 7 lathe selected for refurbishment. It appeared to have suffered more from mis-use than wear As a Super 7 user for the best part of thirty years now, I was recently invited to visit the Myford factor Nottingham to see this reconditioning activity in progress. Managing Director, Christopher Moore sugg I should follow one particular machine through the workshops, observing each operation, making note photographing as I wished.

Having nominated and examined a particularly poor example (Photo 1), I to travel to Nottingham and call in at the works on a Monday afternoon, then to spend all of Tuesday of Wednesday following the component parts through the re-working process and, hopefully see the reassembled to working condition. As it happened, this did not prove quite to be possible due to the m large slideway grinding machine deciding to expire at the crucial moment. Some time was lost while a machine, currently set up for other work, was re-configured to carry out the task.

I therefore had to le another appointment while the chosen lathe was in the final stages of re-assembly, but I had witness vital remachining and hand fitting operations and the inspection checks, which determine the accurac finished product. On arrival at the factory on Wilmot Lane I was greeted by Christopher Moore and his Purchasing and Production Manager, David Wheat, who then introduced me to Brian McKechnie, the Works Inspecto was to be my guide through the various stages of the operation. A longstanding and experienced me the team, Brian was previously a fitter and would, on this occasion, carry out the majority of the hand and assembly tasks involved in the refurbishment.

Machines would normally go through the works in eight, ten or twelve, but to meet the required timescale, this machine would be treated as a single uni History One of the first tasks was to check the history of the machine in question. Extensive records are kept Inspection Foreman’s office, and it was possible to ascertain that it had been supplied new through a Gloucester in March 1966, on a cabinet, complete with motor. The customer was the local Education the final destination being a comprehensive school. At some stage a quick-change gearbox had been this had subsequently been removed.

Photo 2 A selection of the components laid out for examination prior to rework Initial examination Examination and initial dismantling of the machine revealed where reworking would be possible and w replacement parts would obviously be required (Photo 2). Subsequent checks at the re-assembly sta also result in the need for new components. The initial list of replacements was:- Bull wheel Back-gear cluster Rear spindle bearings Sleeve gear y in ested that s and arranged and most machine otor of a second ave for ed all the y of the r, who mber of fitting batches of t. in the n agent in Authority, fitted, but here ge could

Стр. 3

12/01/11 08:38 Follow a Myford Lathe Rebuild - Myford Factory Rebuilds Page 3 sur 13 http://myford-rebuilds.com/epages/eshop433741.sf/en_GB/?ObjectPath=/Shops/eshop433741/Categories/Follow_a_Myford_Lathe_Rebuild Feed nuts Feed screws Top slide base and gib strip Top slide tool clamp (stud) Tailstock cam and eye bolt Drive belts Felt wiper for saddle Lubricating wick for spindle bearing Re-machining Prior to my arrival, a number of items had been sent for cleaning and repainting, a process which is c on an ‘on-condition’ basis. These included the bed, tailstock body and belt guards. Painter Alec.

Jawo matched the colour to the original grey, colours having been changed to green and blue for various m over the years. As soon as the paint on the bed was dry, machinist Chris. Musson set the bed up on on a large horizontal milling machine in order to re-face the sides of the shears. On a new bed, all fo are gang-milled at one setting, using ceramic inserts in the cutters. When reconditioning, however, ea treated individually, removing up to a maximum of 0.005in. from each. In this case, around 0.002 to 0 was sufficient to clean up, the ceramic cutters creating an excellent surface (Photo 3). Photo 3 Milling the first bed shear side using a cutter with an inserted ceramic tip.

(Note that the machine guard has been retracted temporarily to allow a clearer view) In order for me to be able to see as many of the processes as possible in the time available, a numb required operations were being carried out concurrently in different parts of the factory. I was given co freedom to travel between the various locations, making notes and taking photographs as I wished. I most welcome wherever I went and detailed information was freely available. It made for a most plea experience, and reminded me of my days in industry when I always enjoyed the opportunity to visit th machine and fitting shops to discuss problems first-hand with skilled operators.

Photo 4 Grinding the bed mounting feet faces arried out rski had odels a fixture ur faces ch face is .004in er of the mplete was made surable e

Стр. 4