Looking? Shaping Attachment For Bridgeport Mill, Attaches On Spindal

I have both the Bridgeport slotting head and was lucky to find a Volstro slotter that slips on oner the spindle years ago at the Cabin Fever Expo. It was a little shop worn,but never used. When I took it open,the red grease inside was completely undisturbed.

The Bridgy head has a 4" stroke,and a small 3 phase motor. I was very fortunate to have an identical 1/3 H.P. motor in 1 phase on hand. I have been afraid of breaking off the end of the ram where it is mounted,so have been quite content with just the 1/3 HP motor. The Taiwan made one seems a lot more powerful. Perhaps TOO powerful.

We used my B.P. slotter to cut the throats of many,many wooden planes we made for the museum where i was toolmaker. I had thought for quite some time about how the complex escapement of wooden planes could be cut in a reasonably short amount of time,as opposed to laboriously hand chopping each one as I had done in the past to make planes for myself.

We made powerful wood cutting chisels with round shanks to fit the slotter. Then we made sharp,large toothed saws to saw out the deeper grooves where the wedges jam the plane irons into place.

First,the escapements were drilled out as much as possible with Forstner style wood bits. The throats of the planes where the irons came through were routed out with a long router bit I was lucky to have,for they are not common. A small machine shop where I used to live made router bits for the furniture industry,and I picked up a lot of odd router bits that were not to req'd specs,but were perfectly good to use.

Then,the slotter was used to chisel away the inclines of the planes,and the other angular parts of the escapement. Sorry about the huge and tilted image. I can't find the regular one. There were 5 planes in a set,and 80 craftsmen in Williamsburg who used planes. I only have this picture of a batch. Wish I'd been more diligent in making pictures. That's my journeyman Jon on the right. Roll the screen to get the whole picture.

The slotter worked out very well,because it left straight chisel cuts,like the originals would have had,rather than router bit cuts,which would not have been acceptable.
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Here's a picture of a batch of planes,and a jack plane made to 18th. C. style. The blacksmith's shop made the blades. You can see the multi angled escapement that had to be cut in each plane.IMG_0405.jpg
 
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The little Volstro cost big bucks when they were still being made. I was lucky to get a NOS one,as mentioned. It has a 1" stroke. You make your own slotting cutters out of 3/8" HSS lathe tools. I also make them smaller,and fill out the slotter's groove(where the cutters are held) with smaller square stock,like 1/8" square if I use a 1/4" tool.

There is a cylindrical cam inside the unit,with an angled groove that runs clear around it. A ball bearing follower(which is a standard part available in the MSC catalog),runs in it. The little unit is not for real heavy work,but neither is the Bridgeport slotting head. Both were intended for slotting things like grooves for keyways in gear bores,etc.. My use of the big slotter for making wooden planes was unique.
 
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Volstro made wonderful tools, shame they are gone but cnc did them in I am afraid. I love my rotary milling head what a wonder!
 
So Inflight, did you win the one on ebay? Does anyone have a clue on where to get these, or if someone takes one a part could you send or post pics so I could get a look at all of it on the inside?
 
Great deal,inflight!! I paid twice that for my Volstro.

Volstro was bought out by another company,and for some reason was never allowed to make any more tools. Seems like a waste of money on the part of the other company. I think Volstro's line of tooling was pretty obsolete anyway,except for guys like me,though I WOULDN'T have paid their prices for new products. Their rotary milling attachment was over $3,000.00 near their end. I spoke to the guy who made the first one I bought,which was new,but had the spindle snapped off.

I can't recall the price of their slotter,but I'll bet it was over $1500.00 anyway. So,I was very happy to find mine much cheaper than that.

Most commercial machining is CNC these days,so most companies would not be buying their attachments. They probably would have gone out of business soon anyway. I have found the circular milling unit to be very useful. With it you can do work that would be a lot more complex with a rotary table alone. But,the unit is delicate(as is most of their things). Only ever use a maximum of 3/8" end mill in it,and take light cuts only. Forget using the power feed at all. It runs WAYYYYYY too fast. I don't know why they added it anyway. It cannot be altered as it runs off the powered wheel on the Bridgy's head(which is for power downfeed when engaged.) It runs so fast,it leaves big chops in the work as the unit whirls around.

The first one I bought had the spindle snapped off. I think their spindle was left way too hard.Replacing it was what I talked to their tech about. At the time a new spindle was about $119.00. I made my own. Turned out it was not very complicated. I liked my new spindle better than the original,which seemed fully hardened and hardly tempered. Plus,it had a 3/8" hole up the center which weakened their spindle. I left mine solid. He said the hole was where they gripped it for grinding. Some ham handed machinist apparently broke the spindle right off the new unit,and it was never used again. Subsequently,I found 2 more units. One for the shop at work,one for Jon,and found a brand new one with collets in their cardboard boxes for me.

The unit is a bit heavy for me to get onto the spindle. You need 3 hands. What I do is lay a piece of wood on top of the vise,set the unit on top of it,and bring the spindle down into the hole. Then,tighten the screws to clamp it to the mill's spindle. Then,raise the spindle back up till the attachment butts up against the mill's head. Then tighten the drawbar.
 
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Thanks for the link to the Volstro slotter at $999.00. Mine is a lot nicer,but that gives me an idea what I could ask if I ever decide to sell it.

Last time I noticed,Bridgeport slotting heads were running $1400.00 range. Now apparently they are more like $2400.00. More info for me to store,though when I decide to sell it,I probably will be too messed up with arthritis to crate the thing!

I don't know why the Asian copies have such large motors. The original Bridgy ones have a 1/3 HP as I mentioned. I'd MUCH rather have my unit stall out than snap off the end of the cast iron ram. Even with 1/3 HP,geared down,my unit has performed very well. Too much power encourages the ham handed to take too large a cut and damage something. Ever seen a Bridgy ram for sale? NO!!! Wouldn't work anyway on my clone.
 
Keith Fenner on YouTube has several posts where he uses his slotting head on his K & T mill. He calls the slotter a Jumping Jack. You might want to add that to your saved searches on EBay
 
I have the original slotter attachment for my BP collecting dust in the corner of my shop. It works fine, used it once just to try it out (wired for single phase 110V).
If anyone is interested in acquiring it let me know (it is in Southern Ontario, Canada).
 
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