Sign in to follow this  
Dwight Brown

Dov Schmidt Bending Iron

Recommended Posts

Janito: the problems with my Chinese bending iron were 1) live supply wire routed too close to hot lower surface, causing the insulation to start to melt after about 10 minutes, 2) no safety ground.

John,

I was also concerned about the safety of the Chinese units, so thank you for the info.

I have just opened my iron - which is the digital type. There are 3 wires going into the iron heating element. Two are red and have an additional plastic tube around them. They appear to go deep into the iron. The red tube touches the metal case and I can see it is going to get very hot and will probably melt. The other single wire has a woven fibre (silk?) sheath around it. It does not go deep into the iron.

I can see the potential problem with the red covered wires. What is the appropriate fix?

With genuine thanks,

Tim

Share this post


Link to post
Share on other sites
John,

I was also concerned about the safety of the Chinese units, so thank you for the info.

I have just opened my iron - which is the digital type. There are 3 wires going into the iron heating element. Two are red and have an additional plastic tube around them. They appear to go deep into the iron. The red tube touches the metal case and I can see it is going to get very hot and will probably melt. The other single wire has a woven fibre (silk?) sheath around it. It does not go deep into the iron.

I can see the potential problem with the red covered wires. What is the appropriate fix?

With genuine thanks,

Tim

Hi Tim,

The leads going directly to the heating element should have heat resistant insulation and should therefore be OK. In my case it was the main supply cable (ie the one connected to the mains plug) that was incorrectly routed internally. This is just regular mains cable and so the insulation melts if placed too close to a hot surface. Is your iron grounded?

Cheers

John

Share this post


Link to post
Share on other sites

I posted about this iron in another thread before - but this is what i use and i like it just as well as a gewa bending iron. It's stable - good heat distribution exct... I like the size of it as it's perfect for putting in my bench vise.

I do try to keep the aluminum clean as possible so I don't end up with oxide ending up in the wood. Steel wool - some water - it's good to go.

Share this post


Link to post
Share on other sites
Hi Tim,

The leads going directly to the heating element should have heat resistant insulation and should therefore be OK. In my case it was the main supply cable (ie the one connected to the mains plug) that was incorrectly routed internally. This is just regular mains cable and so the insulation melts if placed too close to a hot surface. Is your iron grounded?

Cheers

John

So John it sounds like you just need to replace the supply cord with a grounded one? Also since everyone is reporting that the shape is good, I'd like to know if this unit can be rebuilt successfully and economically. I would'nt want to have to drill out and replace element or anything like that, componet swapping and rewiring I can handle. I just lookend on Ebay and for $89.00 plus 34.00 shipping does'nt seem too bad. I like that the iron is solid and well shaped.

Maybe I 'll go this route...if rebuild will not be too difficult.

-Ernie

Share this post


Link to post
Share on other sites

I must have been lucky because I did buy this chinese bending iron and apart of the "ground cable" issue it did work fine. No problem with the main power wire, no melting. I simply turn the power off after I have bent half of the ribs. There is enough heat for the rest.

Share this post


Link to post
Share on other sites
Hi Tim,

The leads going directly to the heating element should have heat resistant insulation and should therefore be OK. In my case it was the main supply cable (ie the one connected to the mains plug) that was incorrectly routed internally. This is just regular mains cable and so the insulation melts if placed too close to a hot surface. Is your iron grounded?

Cheers

John

John thanks for the reply.

No, mine is not grounded. It would not be problem to do so, but would that be a life saver in the event of a short? It is usual in Oz for domestic power circuits to have a "Safety Switch" at the fuse box. I think the correct term is earth leakage detector. My understanding is this watches to voltage on the neutral and cuts the power if it rises and the cut off is faster than a heartbeat. It is very sensitive, a piece of bread touching an element in the toaster will trip it. Of course, the thing with devices like this is never to need them.

Regards,

Tim

Share this post


Link to post
Share on other sites
I posted about this iron in another thread before - but this is what i use and i like it just as well as a gewa bending iron. It's stable - good heat distribution exct... I like the size of it as it's perfect for putting in my bench vise.

I do try to keep the aluminum clean as possible so I don't end up with oxide ending up in the wood. Steel wool - some water - it's good to go.

Hi Andrew

What about the electrical issues that were mentioned? Is your power supply cord a two or three prong?

I'm seriously thinking of buying one of these off Ebay.

Share this post


Link to post
Share on other sites

In North American building code, the white wire is grounded, but be careful, the left and right plug "blades" are different. I would replace it with a 3-wire power cord.

Share this post


Link to post
Share on other sites
Before any of you electrocute yourself, do a little reading on why toasters are not grounded. :)

Mike

Toasters are a special case, due to the tendency of people to poke knives and forks into the slots to remove stuck slices of bread. In this case shock hazard can be increased if the case is grounded, so historically, they have been supplied with 2-wire (ungrounded) cables. Nowadays, however, toasters are designed with the inner and outer casing electrically isolated from one another, and an outer case ground is fitted to modern toasters (at least in the EU).

Bending irons should be fitted with a 3 wire cord and case grounded . No doubt. The way a bending iron is used is a classic scenario for a nasty electric shock if a fault develops that leads to the live wire contacting the case. If you have a good earth leakage circuit breaker in your supply, as Tim mentions, this will save your bacon, but I wouldn't like to rely on it totally.

Of course, if you are going to do this modification, make sure you know which wire is which!

Share this post


Link to post
Share on other sites

I think a bending iron most definitely needs to be grounded. If you have a commercial bending iron like the Ibex (I bought mine from Metropolitan Music about 30 years ago and it is grounded) you can use a multimeter like this: http://www.amazon.com/Digital-Volt-Meter-V...r/dp/B001RSREKI to test continuity from the ground blade (the third - round one) on the plug to the metal part of the iron - it should show close to 0.0 ohms resistance. That means that if the insulation on the hot wire gets damaged and the exposed wire comes in contact with the iron or gets water dumped on it, the current will go to ground instead of through you, the violinmaker.

The fact that the working part of the iron is metal and you are using water to help bend the ribs means you should also have a ground fault interrupter outlet installed to plug the iron into. Something like this:

http://www.warehouse-lighting.com/item/108...CI-Outlets.aspx

If you are unsure that your outlet is properly wired check with one of these or something like it:

http://www.amazon.com/Electrical-Receptacl...r/dp/B0012DHVQ0

If you are still unsure, have a professional check it. Electricity is not something to guess about.

Share this post


Link to post
Share on other sites

For those who have a digital readout, can you tell us what is the best temperature to bend at?

Is it the same for all, linings, purfling and ribs?

Share this post


Link to post
Share on other sites
For those who have a digital readout, can you tell us what is the best temperature to bend at?

Is it the same for all, linings, purfling and ribs?

I have it at 160C for everything. Works for me.

Regards,

Tim

Share this post


Link to post
Share on other sites

First, who in this thread is a certified electrician? I am not.

I tested my 110V (sic) unit and found no connectivity with the case and line voltage. The case is not grounded, but that is OK according to what I know about appliances. Again, unlike the other contributors, I claim no electrician certification, just my observations.

As for the temperature, I use 140C.

Mike

Share this post


Link to post
Share on other sites
First, who in this thread is a certified electrician? I am not.

I tested my 110V (sic) unit and found no connectivity with the case and line voltage. The case is not grounded, but that is OK according to what I know about appliances. Again, unlike the other contributors, I claim no electrician certification, just my observations.

As for the temperature, I use 140C.

Mike

I'm certainly no sparkie, but following this thread I'm not going to use my iron until it has been checked by one. Our OHS laws mean that all electrical devices in the workplace are tested and tagged each year. I'll get the same done with my unit at home. Water and 240V is not a good combination.

Tim

Share this post


Link to post
Share on other sites
Does anyone know if Dov's iron is a better quality than the Chinese ones. They look the same from the outside.

I just noticed his price is considerably higher.

Inside mine (Dov Schmidt unit) the temperature regulating device has Chinese characters on it, if that means anything.

Tim

Share this post


Link to post
Share on other sites

I did notice a similar look to my import iron. I'm hesitant to comment here, since I like Dov as a supplier for pegs and other parts. :)

Share this post


Link to post
Share on other sites
Inside mine (Dov Schmidt unit) the temperature regulating device has Chinese characters on it, if that means anything.

Tim

Those characters literally translated probably state: Do standing not in concrete floor on pools of water, working bending at ribs!"

Share this post


Link to post
Share on other sites
I did notice a similar look to my import iron. I'm hesitant to comment here, since I like Dov as a supplier for pegs and other parts. :)

I hope my comments are not taken as being critical of Dov Schmidt, I have had nothing but good service from his company for a few years now and will continue to buy from him. Strictly speaking, I should probably not be using any electrical device that has not been certified to meet Australian standards. I see any problem, if indeed one exists, as being mine.

Regards,

Tim

Share this post


Link to post
Share on other sites
Does anyone know if Dov's iron is a better quality than the Chinese ones. They look the same from the outside.

I just noticed his price is considerably higher.

They are the same, Ernie. Take a look at post #22.

My unit is 220 volts and works fine. I took a look to the inside parts and they seem to be fairly correct.

If any of you want me to post some pics of the iron, please let me know.

Share this post


Link to post
Share on other sites
First, who in this thread is a certified electrician? I am not.

I tested my 110V (sic) unit and found no connectivity with the case and line voltage. The case is not grounded, but that is OK according to what I know about appliances. Again, unlike the other contributors, I claim no electrician certification, just my observations.

As for the temperature, I use 140C.

Mike

Mike, I have no interest in scoring points off people on an internet forum. If I am wrong about this, and, for example, Tim's iron gets a clean bill of health from his electrician, then that's fine by me. I won't be using mine until I've rebuilt it properly.

PS. You will, of course see no connectivity between the case and line voltage unless a fault develops, such as the insulation on the live wire melting, as it had begun to do on mine.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.