Hegner Scroll Saw advice

[Roughcut]

Hi, Firstly I had better admit that im a complete amateur as regards scroll sawing.
However I bought a second hand Hegner Scrollsaw earlier this year with the intention of having a go.
To be honest the scroll saw has sat in the garage all that time due to having a busy work schedule this year and not having much time for a lot else.
Firstly on start up the saw seems quite loud, loud enough that I wouldn't want to be standing over it for more than a few minutes.
Is this normal?
I've tried to make sure all screws and bolts are fully tightened to eliminate vibration where possible and even tried setting the saw up on a piece of kitchen worktop on top of the bench to dampen vibration. But it still seems to make an annoying loud metallic vibrating sound.
Also the top arm seems to be cocked slightly to the left when viewed straight on. It just does not look right to my eye.
Could this be why the saw is vibrating so much?
Please view the following pics: I have included a couple of pictures showing the cocked arm and a shot with a small spirit level showing how far the bubble is out of level when held against the top arm. (The bed of the saw is level)

 

[scrimper]

I can't see properly in the small image and it won't enlarge for me but from what I can see it looks to be bent at some point.

Regarding the noise level unless something is worn out it should not be noisy. My Hegner runs very quietly and is vibration free, have you got it bolted down to a stand or bench? It will vibrate if not. If free-standing it will vibrate no matter how firm the surface, it must be bolted firmly to a firm and substantial bench or stand. A metal stand will be better than a wooden one (it's something to do with the frequency of vibration) though I would not suggest a Hegner stand they are way to expensive!

My Hegner is mounted on a home-made stand which is of heavy build.

 

[powertools]

I don't own a Hegner but for even the cheapest scrollsaw to make so much noise that you can't stand it for more than a few mins something is wrong.
To achieve any decent results the blade needs to run at right angle to the table and I guess that the reason that yours doesn't is also the cause of the noise and vibration.

 

[martinka]

It might be a silly question, but do you have a blade in, and tensioned, when you are trying it? There certainly seems to be something amiss with the top arm, but I'd like to see better photo's

If you have a blade in and it is tensioned and still knocking, either something is catching, or one of the bearings is loose/worn/knackered. There's a brass bearing at the back of each arm and a link arm with two bearings from the motor to the bottom arm, try them for any play. There should be none at all. It should be obvious if something is catching to make the noise. Is it possible to make a short video of it running?

Martin.

 

[ChrisR]

Roughcut.

Check the points that Scrimper and Martin have made in their posts, regarding noise.

From your images the top arm is certainly off the vertical line, and this will have to be corrected by straitening if possible, or a new arm irrespective of noise . With the arm as it is I would think that any blade would break on the first cut stroke.

Take care.

Chris R.

 

[Roughcut]

Hi and thank you for all your replies.
Just to answer some of your questions/comments, yes I have tried using the saw with a blade.
And the saw is bolted down to a sturdy bench with two coach bolts and 18mm mdf packers.
I have used 3/4" pine on the saw and it seems to cut without breaking a blade. I have tried doing straight and curved cuts and the surface finish seems good.
The blade looks fairly straight in operation but is very slightly kinked at the top where it is attached to the top arm.
I took another look at the saw at the weekend and noticed that there was a lot of mdf dust around the motor and base (from the previous owner).
So I decided to give the saw a clean, it was after I took the Coverplate off that guards the Link and Bearing connector that I noticed the screw that connects the Link and Bearing connector to the Eccentric was quite loose.
Then upon removal of the screw I noticed there was no lock washer, so the screw is becoming loose because of the lack of a lock washer.
I feel this is at least one reason why the saw is vibrating so much as after tightening the screw sufficiently and running the saw it seemed much quieter but soon reverted back to it's previous loud vibrating noise, due to the screw loosening.
I will try and track down the correct lock washer required maybe from Hegner and will report back on the result.
But from what I've seen and with the absence of at least one washer I conclude that before the saw was in my possession someone has buggered about with it.

 

[martinka]

If the link arm has been adrift, make sure the little spacers that go behind the bearings are still there. The spring washer is nothing special and should really be OK without. If it came loose again immediately, I'd be looking for another cause than a missing washer.

Martin.

 

[Roughcut]

Just an update on this:
I still have not been able to work out why the top arm is slightly cocked? :?
However I replaced the m5 x 16 cap screw with a new one, along with an m5 spring washer (which was previously missing).
I've just started the saw up and left it running for 5-10 minutes and I have to say it is a vast improvement on how it was sounding before, and the sound level is what I would deem acceptable.
The lack of a spring washer was previously causing the cap screw to loosen and allowing the eccentric to run loose which I believe was the cause of the rattling metallic sound I spoke of before.
Anyhow I will try and think of one or two small scroll saw projects for this amateur to have a try with, and will see how the saw continues to perform.

 

[martinka]

Can you take a better close up photo of the front of the arm? The ones you posted are too small. It looks to me as though the bracket holding the thumbscrew is bent much more than the arm but that may be an illusion. If the arm is as bent to the same degree as the bracket looks to be, check it at the back end as well. Also, check the pivot bolt in case the saw has been dropped and bent the bolt. Undo it a full turn with a 17mm spanner, it should be obvious if it is bent. Good to hear you are getting somewhere with it though, at least it sounds to be usable..

Martin.

 

[Roughcut]

Hi Martin I had to resize the photos to be able to post on the forum.
Im not great with computers but I will try and see if I can resize the photo to make it larger.

 

[martinka]

The pivot bolt at the back of the arm looks shiny as though it is zinc or cadmium plated, but all the ones I have seen are black. Is it shiny or am I seeing things? I'd definitely want to check that it hasn't been replaced by a different bolt, and check to see whether it is bent.

Martin.

 

[Roughcut]

Ok so I've had ANOTHER look at the saw today. :roll:
Following on from a comment Martin had made regarding the pivot bolt on the top arm looking different from the usual bolt that is used.
I believe you are right Martin, and I thank you and other contributors to this post so far.
On closer inspection the pivot arm bolt on the bottom arm has a black coloured bolt head, the bolt on the upper arm is a shiny plated finish.
On removal of said bolts it is easy to see they are not both the same, the bolt on the left is from the bottom arm and is genuine Hegner. The bolt on the right is from the top arm is looks to be a replacement and non-original (photos attached).

However the non-Hegner replacement bolt does not appear damaged or bent.
It was then that I noticed it was the casting that looked slightly bent (see photo with square for comparison).
I believe this is what Hegner call the C-Frame?
It is definitely bent or out of line, but doesn't appear cracked or damaged.
Is there a way to try and straighten this C-Frame, or will I need to buy a new C-Frame from Hegner?

 

[ChrisR]

Roughcut.
Looks as if the C frame as you call it is the root of your problems. I don’t think you have anything to loose by trying to straighten/true up, as it is of no serviceable use as it is, if you are unable to straighten or it breaks, only then do you need to contact Hegner, or find another S/H saw to use as spares.

Hegner will certainly be able to supply you with a replacement frame, but I dread to think what the cost will be. :shock:

Take care.

Chris R.

 

[ChrisR]

Just had a look on the Hegner UK site.

Replacement (C Frame) for M1/M2 £91.32. inc VAT

So not quite as bad as I thought it would be.

Take care.

Chris R.

 

[Roughcut]

Yes Chris I had already looked on the Hegner website to see how much a new one would be.
A new one is not cheap (none of the Hegner spares are), but it is affordable if I really need to buy a new one.
I think I will take a closer look and see if I can do anything to straighten the C-Frame, as I agree with you that I have nothing to lose.

 

[martinka]

The frame is cast, though I am not sure whether it's cast iron or cast steel but more than likely cast iron for the extra rigidity. If it's cast iron it will need heat to straighten it. If it's cast steel you might get away with a big vice and a suitable lever, but I'd be looking for someone local who can heat it and straighten it. Good luck with it whichever way you go, and as has already been said, you have nothing to lose.
You could phone Hegner for advice, though they will probably advise you to buy a new frame, but you might find out for definite if it is cast iron or not.

Martin.

 

[Roughcut]

Did my first scroll saw project trial (Steve Good design) this morning to test the saw out, using 12mm plywood :

 

[martinka]

Looks fine to me, you may as well leave the saw as it is. :wink:

Martin.

 

[ChrisR]

Nothing wrong with that. =D>
Just keep on scrolling.

Take care.

Chris R.

 

[Bryan Bennett]

Hi Roughcut Your test I would say has been a success.That certainly looks very good to me.

Bryan