Denbigh Fly Press

[Arc Tourist]

I have taken delivery of my 'new' flypress from @pressbrake. Whats the general opinion on height? I was looking to have the weight arm above my head so I dont get hit with it. That means the workpiece will be about 1300mm which is about sternum height on me. I have heard this is about right, but also heard its too high

I dont want to be stooping when I use it but dont want to get clouted by the damn thing either!

I have a Denbigh No. 6 fly press with the original cast iron stand. For what its worth, the combined height = 34" to top of the press's table, and 64" from floor to the horizontal swing bar. I haven't put it back together yet, but it seems about the right height for dealing with hot forgings, but too low with regard to possible head injuries.

 

[droopsnoot]

How is the top tool removed from a Denbigh fly press? I've got a Denbigh No 3, with a large flat plate as the top tool. I'm now thinking that I might be able to make something up for doing short folds in 1mm or 1.2mm steel, so my first thought was to see how to remove the top tool and have a look at how it's mounted. I can unscrew the mangled bolt in the photo for a certain distance, but then it stops. Should it remove completely? The photos above suggest that it should. When it's unscrewed the tool does seem to move a little, but I didn't want to force it.

I've jumped on this thread rather than opening a new one, please shout if you'd rather I split it off.

 

[Paul.]

You may well have bit of a problem there, the tool is just simply clamped in with the bolt but if the bolt is over tightened then the threads have probably been burred / damaged so forcing it out will at best damage the threads in the ram, or seize up, I would undo it as far as it will come without forcing it, then try turning the tool with a stilson or similar, if you can get it moving then it might be possible to knock it out using a hammer and drift on the little bit of tool that you can see, you might be able to put a pair of blocks between the tool and the press body and use the press upstroke to pull it out.

Then if you are able to get it apart, grind a flat on the shaft of the tooling, and turn or grind down the end of the clamping bolt so that the threads are well away from the clamping action.
Like this quick sketch

 

[droopsnoot]

Thanks for that, I'll have a bit of a look in more detail. When I get the bolt out as far as it will come before it goes stiff, the tool will move a little bit but I didn't try forcing anything. I wasn't sure whether the bolt actually goes into a threaded hole in the tool, or whether it's more like a grub screw. There's a section of thread that is perfectly OK, so presumably it's just the last part that has the problem.

Any thoughts on whether a No. 3 press (which is presumably 3 tons) would be any use at folding? I'm thinking of a base with a piece of angle iron sitting at 45 degrees, and some kind of blade to press down on it. 1.2mm would be the thickest material I'd use.

 

[Paul.]

It will bend that easy, next time I'm at the workshop I'll get some pictures of my self made tooling.

 

[Seadog]

You've two options:
1) wind the bolt out. If the thread is badly damaged it could easily be Helicoiled.
2) drill the bolt out.
You may have an additional problem if there is no flat on the tool spigot, which will possibly have a burr raised. Drilling would obviate this, since you'd just continue until the burr was removed or reduced to the point that it has little strength.

 

[Screwdriver]

It will easily bend 1.2mm sheet, even up to two feet at a time with a long enough (and stiff enough) press tool. I have done that myself (albeit with a Norton 6DB).

That tool has a 1" spigot (yours might be 3/4") that slides about 2-3" up into a circular hole in the hardened steel anvil. There are several potential problems here:

It might not be a 1" spigot but "nearenuff" and clamped in place with the top of the spigot hitting the top of the inside of the hole iyswim. Over time the top of the spigot can mushroom which is why, ideally, the top of the tooling should touch the bottom of the anvil before the spigot bottoms out (tops out) in the hole. It can either rest against the bottom of the anvil or be mounted on a shoulder. You never want to force a spigot any further into the anvil is what I'm getting at.

Because reason number 2. the friction bolt should push against a flattened part of the spigot. As often as not though, they fit into a recess. Combined with point number 1, if the spigot moves it drags the tip of that recalcitrant bolt with it, smearing it out up inside the anvil! Either that or it can bend or damage the threads to the point it will not want to release.

You have to get it out and I would be wary of using heat on this occasion since you can damage the temper in the anvil which might only be surface hardened. It is a precision part! If it looks really tricky, I'd be tempted to pull the whole thing off, get it onto a drill press etc. With any luck it will pop right out without all that faff.

When it does, you may find the spigot is siezed or even mushroomed in the anvil. Easy(er) way to get it out is to retain the tool in a sort of jig or with chain/strap etc. but something that would allow you to use the press tool to pull it out for you. Wind it UP and you'll be pulling on the spigot with the 3 tons at your disposal in a nice controlled shock. Don't rip out the bed T slots, a block of wood under the plate either side would suffice (arranged so that liting the tool with the wooden chocks UP means the wood hits some solid part of the flypress body before the tool tops out. A balanced pull is essential, that hole is very precise on both of the flypresses I have owned to the point where a well machined spigot only fits when you align it properly and the slightest ding will have it jam.

TBH, I wish I'd drawn a diagram. a very wordy way to say something that's actually pretty simple...

 

[droopsnoot]

Thanks for the responses, I will have a closer look at it when I get there this afternoon. I've got a folder, but I often run into a problem with other folds getting in the way, and a recent classic car prog on the TV showed this kind of folder and it suddenly hit me that the fly press could perhaps be pressed (sorry...) into service and I could get a bit more use out of it. A new project requires six bends per piece, and I can only do one in the folder, and the shape of the item means that it is tricky to put into a vice for most of the rest.

Fortunately heat is the one thing I can't cause untold damage with, as (other than an electric hot air gun) I don't have any heat. I did think about drilling the bolt out, part of my reluctance of course is that at the moment I've got a working press that does a job every few months quite well and it would be a pity to stop it doing even that.

Some interesting thoughts, I will bring this up to date later.

 

[Morrisman]

Someone selling a whole load of fly presses on Facebook, in Dudley I think, if anybody is in need.

Fly presses assorted sizes

Assorted vintage fly presses for sale. Sizes 2 up to 7 available. Prices from £80, Happy to do a deal if purchasing multiple. Please message to arrange to view. Collection only, we can help load...

www.facebook.com

 

[droopsnoot]

Well, I've made some progress. I found someone selling fly-press tooling and went up to visit them this afternoon, and while chatting about my press it became obvious that I have no option but to try to remove this bolt. If I undo it, it only allows the existing tool to move a bit, not to actually come out. And as the worst that can happen is that I take the thread out of the ram and need to either drill it out larger and tap it, or perhaps helicoil it, I got some mole grips on it this afternoon and it's out. The thread doesn't look terrible, and I can screw the bolt back in without any trouble. I do need to replace the bolt because the head is very badly distorted - that's why I used mole grips on it, not because I did.

Tomorrow I'll clear a bit of space around it and test out the new tool. It's fairly basic, but it's a block with a V-groove and a blade to press the steel into it. I also bought another top tool that has round bar for creating rounded bends, but I'll need to knock up a lower piece to use it. Now I have a pair I can compare that to what I need.

 

[Screwdriver]

That bolt needs to be as flush as possible within minimum stick out. Surprising how often it still manages to get in the way.

 

[droopsnoot]

That bolt needs to be as flush as possible within minimum stick out. Surprising how often it still manages to get in the way.

Cheers, I hadn't thought of that - all the work I've done up to now has been just using the flat tool to press small shapes, so there's no way that the workpiece can get anywhere near it. Once I'm folding things, I can see it may do.

 

[Screwdriver]

Sure I might just "walk that back" a bit since I was thinking about an extension I use which has the same fixture. It's just a 1" diameter 6" long holder that has a hole in the bottom for smaller press tools, typically punches. That's when such a thing really gets in the way. I am planning to do an exposé for all my press tooling as a YouTube vid.

Been planning that for ages, don't hold your breath! I'll take a snapshot next time I'm out there because while I am quite familiar with my own range of tooling, I am not sure what is commonly available or in frequent use.

 

[droopsnoot]

That would be interesting, I'm sure there's loads of stuff I could do with this press that I haven't thought of. The chap I visited told me they had loads of tooling but had sold most of it last week. I need to see how well it folds with this one before I start thinking about doing other stuff with it, though.

 

[Paul.]

Flypress tooling is dead easy to make, especially for home or low volume work, here is a simple bending tool made from flat bar, the bottom tool is made from two pieces with an angle gound on them then screwed together to make a vee

And this is a short one made from black bar, this one has had a lot of different jobs, hence the bits ground out of it, the vee block is a bit of pressbrake tooling that I happened upon with a simple bracket to mount it to the press bed, as you can see, mine has also had a clamping screw problem, (before my ownership) and has had a new hole drilled and tapped in it.

And this is one little job I've just done on it, stainles steel roll card holders for fire appliances.

 

[droopsnoot]

Thanks for that, I'm trying to balance out making use of it with getting actual stuff done and not messing with it too much.

Just for a test I put the new tool in it today and folded a few bits of metal, and I'm impressed. It's a nice clean sharp fold, I've only tested fairly narrow pieces so far but it's happy to fold 1.6mm mild steel without trouble. I've already run into a problem with the width of the v-block preventing a second fold for a particular job, but at least with this I can see a solution for it by either grinding a bit off my v-block, or your photo of the home-made one made with two pieces bolted together is another dead simple idea I hadn't thought of - I was focussing on how to get the v machined out of a solid bit.

These are the three tools I bought - the one on top left was really a "just in case" thing as I don't normally need curved bends.

I found that I've got a length of 1" diameter bar that I use for beating metal around, so that may well be getting re-purposed in the future as mounts for various things. I am lacking big fabrication companies in the area that might have a bin full of off-cuts of suitably thick material that I could use for this, but I'll have a look around a bit more. I've just grabbed a load of thicker off-cuts but they're around 3mm, the blade in the photo is 5mm steel.

With a bit of cleaning up of the end of the thread, the bolt has gone back into the press without too much trouble, so I think I've got away with not damaging it. It needs replacing because the head is really bad, and I need to borrow a tap to run through the hole just to make sure - unfortunately it seems to be M11 x 1.75 and I haven't got one, but I think a mate has.

 

[h-dom]

If you need any 1" bar let me know. I actually use 25mm, chamfer the top and it's a lovely fit. I have loads and could cut you off a few bits no problem.

 

[droopsnoot]

If you need any 1" bar let me know. I actually use 25mm, chamfer the top and it's a lovely fit. I have loads and could cut you off a few bits no problem.

Thanks, I may well be in touch.

Having had a quick search on eBay for a suitable replacement bolt, I am now hoping that it's actually not M11, perhaps it is 7/16" UNC. That seems more likely, given the age of it and how difficult it is to get M11 bolts - if it had been drilled out at some point in the past, I can't imagine someone doing that to M11.

 

[Paul.]

Another little tool knocked up ages ago made in just in a few minutes from nothing, for pressing the shape in a dished tube end, the working face of the ball is cleaned up with a flap disc

This is how they come out

And this is what they are for

 

[Morrisman]

Thanks, I may well be in touch.

Having had a quick search on eBay for a suitable replacement bolt, I am now hoping that it's actually not M11, perhaps it is 7/16" UNC. That seems more likely, given the age of it and how difficult it is to get M11 bolts - if it had been drilled out at some point in the past, I can't imagine someone doing that to M11.

From memory, M11 is the size they use for seat belts anchor points. No idea why they picked that size.
I think I have a couple, somewhere in one of my bolts boxes.