Domestic bridgeport

[jason spencerParticipant @jasonspencer41535]

Well, following on from my previous thread, A friend pointed out I've room for a bridgeport mill, they seem to be quite cheap as I guess they're on the large size for a lot of domestic use, also quite common.

The spares/parts avalibilty is very appealing. What would be the reason not to go for one over a smaller machine?

Once again, sorry for all my questions, I just want to get the right machine first time!

[jason spencerParticipant @jasonspencer41535]

Bridgeport as a home machine

[Francis SykesParticipant @francissykes95134]

I've got a friend who's got a lovely Bridgeport in his garage. They're a medium duty machine, it'll be more rigid and capable than a bench top machine, the disadvantage is that second hand you'll need to carefully check the machine for its condition, as many have lead hard lives in an industrial situation.

Many are three phase motor equipped, so either a phase converter is needed for these machines or going for inverter drive may be necessary if, like the majority of us, you only have single phase (240v) supply available.

The machines had various options too as far as I can tell, and you may get ones with/without power feed, coolant pumps (agian could be three or single phase) – I think they could have different heads too. I expect Lathes.co.uk would probably supply more info on the variants.

If you're going to look at a machine, take a friend who'd know what to look for in miling machine condition?

[Francis SykesParticipant @francissykes95134]

Here's a link!

http://www.lathes.co.uk/bridgeport/

[KWILParticipant @kwil]

1.25 ton lump of cast iron, versatile but get a good one, I have one with a 48" table. Not for the faint hearted though.

[jason spencerParticipant @jasonspencer41535]

I've found a used one thats been owned from new by a motorracing enginnering company, its being replaced with a CNC machine, they said its been powered for about 5 hours a week powered slides etc.

Decisions decisions!

[JohnFParticipant @johnf59703]

One or two thoughts–what size of items are you intending to machine, if it is all small parts why run a large machine, then on the other hand what will do large will also do small !

I have the option of both a Bridgeport and an Emco FB2, I do a lot of small parts for which I always use the Emco — if its larger components or a lot of stock removal then the Bridgport comes in its own. Horses for courses. If it came to a choice of one or the other and I had the room I would go for the Bridgeport.

It souds as though the one on offer may well be a good buy Francis's advice to take an experienced machinist with you is good advice. Turret mills are a very versatile design and well suited to "our" many different machining situations.

Not cheap but there is a company in Yorshire who specialize in overhauling Bridgports to avery high standard–if you need it I can find the details but will have to dig them out.

John

[jason spencerParticipant @jasonspencer41535]

that's the thing, It'd be useful for the 6cylinder engiens I play with(old nissan/datusn ones), also used for my motorbike engines(in line 4's), and generally making bits for both.

I think part of the attraction is that its a beautiful thing to look at.

[Clive FosterParticipant @clivefoster55965]

From the home shop / ME point of view there are two big wins when going for a Bridgeport as opposed to a smaller, hobby market machine.

Firstly the price – performance compromise in engineering is comfortably above anything we'd need to do. Industrial users expect what they buy to do what it says on the box. Hobby types have to persuade what they can afford to cope with what they want to do.

Secondly the space for setting up jobs. With smaller machines it can be a right faff getting room to fix, align and measure a job. On a Bridgeport just winding the handles will win enough access to set-up pretty much anything you can handle on your own. I had one of the big dovetail column bench-top mills with R8 spindle before and there is no comparison in ease of set-up. How you chaps with the smaller machines manage I shall never know.

Big disadvantage is that it gets much harder to turn down 12" to the foot "please fixit" jobs 'cos you don't have the easy "my machine is too small" excuse.

Major warning. The head is heavy and seriously unbalanced when rotated about the horizontal axis via the worm drive. That drive isn't exactly over-engineered so wear or abuse can soon erode the safety factor. I'd not attempt to rotate the head solo before inspecting the worm drive and worm wheel to verify that all is in good condition. Mine had a well worn wheel with one bolt missing and a sloppy key. If you do need to rotate it (eg when inverting for transport) get assistance to hold the head and a spanner on one of the lock bolts to snug up if it tries to escape. When rotating on your own do make sure the pull out stop pin is in place. I'd not go past the pin without a helper around, if you are on your own do rig up a safety strap. If pulling off the head fix a strong vertical post to the table, grab it with a collet and stabilise the head with suitable wood blocks or other devices. Now you can use the screw feeds to draw it off or align for re-fitting.

Clive

[John Stevenson 1Participant @johnstevenson1]

Bridgeports are a bit like Myfords, the name sells them.

There are others in the same work envolope like Ajax, Beaver , Elliott I would much prefer over a Bridgeport.

This is not a sour grapes post, I have two Bridgeports but a previous Elliot and a current Beaver can run rings over them as regards rigidity.

If a Bridgeport sells for say £1200 you can get an equal or better Elliot or Beaver for less than £1000.

Another point is the Bridgy varispeed, it's crap, no scrub that it's CRAP.

Go for a step speed model and fit an inverter. If they had had decent cheap and reliable inverters 50 years ago they would not have invented the variable sheave.

[_Paul_Participant @_paul_]

I like my Bridgeport and i think they are good machines but spares can be pricey I recently replaced the "clutches" in my Varispeed which cost a little over £400 for pattern parts, genuine items from Hardinge would have been >£750.

The Abec 7 Spindle bearings can also be expensive and not that easy to set up.

If I buy another I would do as John says and get a step belt head + inverter much less hassle.

Paul

[John Stevenson 1Participant @johnstevenson1]

I repair Bridgeport varispeed motors. I work for two machine reconditioners andd two rewind companies.

Because I'm geared up for doing these i probably get the bulk in the midlands area.

Over a year I probably get 35.

All that wears out on a step speed drive system is a £4.00 fan belt. The belt on a Varispeed is about £75.00

This is what happens to the motor with the sheaves working up and down.

And this is what they look like when they go out 2 hours later.

Another one waiting in the background.

[MikelkieParticipant @mikelkie]

John Stevenson is not wrong, varydrive not only on Bridgeport, but any machine tool are crap

I recently acquired a BP with chromed bedways and worn srews on X & Y
After changing to step pulleys and vfd, ballscrews and nuts on both axes

i now own a near perfect milling machine

I also have a Chipmaster to which i fitted a lumpen two speed gearbox and vfd

after getting rid of the cob variator

[mickypeeParticipant @mickypee]

I have had a BP in my home workshop for a few years and I wouldn't look at another machine as long as you have the space. It is very versatile and acurate and most jobs can be done with ease. Mine is a 3PH model and I have installed 3PH from the road down the drive to the workshop, all done at reasonable cost. A much better idea than inverter but obviously not for everyone if cost is an issue.

All the spares can be obtained and like the previous poster suggested it is important to get as good a machine as you can. If the one you are getting is from a racing business, the chances are it's in good condition, but it all can be repaired/upgraded as you go.

I don't think you will regret buying one, certainly the ultimate for home use.

Email me if you need any help.

Mike

[Anonymous]

I have a 1.5hp varispeed head Bridgeport, running direct from a 3 phase supply. While I'm taking a coffee break from using it here are a few random notes:

* The Bridgeport isn't particularly rigid, but is versatile, especially if you have some of the options such as the horizontal attachment and Quillmaster. I've also got a slotting head on the back of the ram

* I tend to run small cutters fast rather than big cutters slowly on the Bridgeport as I use the same collet system as my CNC mill, for convenience. If I really need to remove metal fast I use the horizontal mill, much heavier and much more horsepower.

* Spares are easily obtainable, albeit at a price

* R8 tooling is widely available at all price/performance points

* Tables come in various sizes, at least 36", 42" and 48"

* To use the full travel of the table you need to have a clear space each side; for my 48" table the handbook lists 84" clearance to make full use of the table travel

* Fitting a 2 axis DRO transformed my machine; I don't miss a third axis

* Inverters are all very nice, but below the base speed of the motor they're constant torque, not constant power

* It would be nice if the cross travel was a bit more than 12"; but one can live with it

* I rarely use my pillar drill, much preferring the Bridgeport for most drilling operations

If I was looking again I'd consider a Beaver mill, but they're rather more difficult to find than Bridgeports. Overall I'm very happy with my Bridgeport and I don't think you'll regret acquiring one. Especially from a race team, as they tend to look after their machines.

Regards,

Andrew

[KWILParticipant @kwil]

JohnF mentions a Yorkshire firm, that will be Terry Braithwaite of Bridlington then.

http://www..braithwaiterebuild.co.uk/

[Gray62Participant @gray62]

I have an Ajax AJT4 which is a bit like a Bridgeport on steroids. Table is 56" x 11", power feed (via 1.5HP motor and gearbox in the knee) to all 3 axis.

It has a vari speed head and I must admit to it being noisy but it is a little better built than the bridgeports I have seen. Replaced the bushes, and Drive belts and all is good.

I run the machine off a couple of inverters, one for spindle and one for power feeds, so the vari speed is not used quite as much as it would normally be.

Cost me less than £1k and they do come on fleabay from time to time.

Same precautions as buying anything ex industry – check it over carefully a it may have had a 'busy' working life.

But I have no complaints and no regrets.

Graeme

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