Introduction: Add a Barndoor to a Worklight

Picture of Add a Barndoor to a Worklight

People who cannot afford to purchase professional lighting units often resort to using halogen worklights. This project allows you to add industry standard PAR56 worklights to the unit.

Unlike other designs, these doors are not fixed to the unit, and can be removed oompletely, or rotated to any angle.

Uses standard steel brackets available from any hardward store

Step 1: Material List

3 x 20mm 'L' brackets
3 x 40mm 'L' brackets
1 x 75mm 'T' bracket
3 x 3mm bolts (10mm long)
3 x 3mm lock nuts
Two part resin adhesive (Araldite)
500 watt work light


Heavy duty vice
Hammer
Screwdriver with 3mm head
Large file
3mm steel drill
Plasticine type adhesive

Step 2: Creating the Brackets

Picture of Creating the Brackets

The first thing you need to do is "alter" the shape of the 40mm "L" brackets to make them into "U" supports.

Grip the bracket tightly in the vice with the bend upper-most. Position it so that the first hole below the bend is half visible, and half inside the vice clamp.

Next, use a hammer, and gently bend the end of the bracket over to about 30 degrees.

Obviously, you will have to put a little bit of power into the hammer blow, but don`t use as much force as you would when knocking a nail into the wall!

This will create the shape shown on the below.

Open the jaws of the vice wide, and drop the bracket in. Slowly close the jaws, and the angled edge will bend to 90 degrees.

(Due to springy nature of the steel, bend the bracket slightly more than 90%; it will open to the correct angle when you open the jaws again)

The top bend is virtually finished; it just needs a little bit of filing to round the corners to avoid causing any nasty cuts and scratches.

The bottom part is a little too long to fit the PAR56 barn doors to the worklight ... And this is where we need to do a little bit of crude / inaccurate measuring.

Most barn door fitments follow the same basic "pattern", ie a ring of metal at the front onto which the doors themselves are mounted, a small recess, and a slightly smaller ring of steel on the back. The clips of the PAR cans fit into the recess to hold the unit in place.

Place the bracket -now shown blue - onto the barn door assembly. Measure the horizontal distance of the worklight between the inside of the metal supports, (the parts that hold the glass. This is the distance you need between the brackets, and thus how much of the lower bracket to remove.

Step 3: Creating the Brackets - Con't

Picture of Creating the Brackets - Con't

In our version, this meant about 5mm had to be cut off the end of the lower bracket, which in turn meant the cut was made through the middle of the lower hole.

These brackets fit directly onto the side of the lamp housing. However, at present, there is nothing to stop the doors crashing to the floor. We have to build a bracket to fit the lower section. Also, the doors are designed to fit a circular lamp housing; our worklight is rectangular.

The "L" bracket is bent as before, but the rear side is =not= cut off.

Time for another bit of crude measuring ... and three pairs of hands!

Place the "T" bracket against the lower part of the window metalwork. It may help if you "glue" this in position with Plasticine type glue used to hold pictures on walls, (such as "Blutak")

Put the doors on top, and position so as the circular opening is more or less central to the lamp. Slide the bent bracket up into the recess and push upwards until it stops against the rim of the barn doors. Mark the position of the bracket on the "T" bracket.
This only has to be a rough approximation."T" bracket.

Once cut to size, the two sections are glued together with two part resin glue.

BE CAREFUL WITH THIS NEXT STAGE
Carefully pries the glass out of the mount and put it aside till later. Place the lower bracket on the work light, and drill three 3mm holes through the top holes.

The next part is very, very easy. Where the brackets will be attached to the frame, you file off the powdered coating to reveal the base aluminium underneath. Do this on the sides and the lower edge.We now need to fix two of the smaller "L" brackets to the side of the casing. These need to be bend slightly to match the slope of the housing. You might be able to use the vice, but an easier method is to use a pair of wide jawed grips that have serrated teeth on each face, and squeeze the bracket between the jaws to about 15 degrees.

Step 4: Fixing the Brackets

Picture of Fixing the Brackets

Open up the window housing so that it is lays face down on the work surface. You will see two little "lugs" inside the moulded into the frame that holds the glass in place. Helpfully, these are in the middle of the frame which helps align the external brackets. Using two part adhesive, smear the back side of the small brackets, and then fix them into position. (The fact that the frame is face down on a level surface will help ensure you get the front of the brackets level with the front of the frame.)

Tip:
Put a little bit of unmixed resin on one bracket, then blend it with the other bracket before squeezing against the frame.

Leave these to "cure" overnight.

Next, smear the "T" bracket with adhesive, and position it over the three holes. After about 30 seconds, slide the 3mm bolts through the holes, and secure the locking nuts on the reverse side. (The nuts should have a little clearance when the glass is reinserted later)

This bracket is fairly secure as it is held in place with glue and screws, but it is still a little perceptible to damage. To ensure rigidity, we add another small "L" bracket to the rear.

Again, once the adhesive has cured, you can proceed to the final stage. Place a large "glob" of adhesive on both side brackets. Slide the cut brackets into the mix and move them around. Swap the brackets and then move into position. (This simply ensures both brackets get a well mixed quantity of adhesive on them) Press the brackets down slightly so the glue oozes.

Note: The brackets do tend to slide around a little, so you will have to keep repositioning until semi set.

Finally, carefully replace the glass into the unit.

The end result is thus:

Step 5: Filter Holder and Extra Tips

Picture of Filter Holder and Extra Tips

If you study the diagrams closely, you may have noticed a gap between the rear of the barn doors and the front of the work light - the area shown red on the graphic opposite.

This allows you to slide a filter holder into this gap so that you can add colour to the light, or possible an A-D (Artificial light to Daylight) filter.

Since the doors are not fixed to the unit, they can be removed and used on other lamps, such as PAR56 cans or our other lamp project.

Note: It`s a good idea to roughly abrade the surfaces of the small clips as this will give the adhesive a better "key" to bond too. The lamp housing will already be "keyed" since you have scraped off the black powder coating to the base metal.

You might like to paint the clips / housing with paint where it has been abraded. Ideally this should be able to withstand the high temperatures produced by the lamp.

To help stop the doors from sliding around within the brackets, you can glue some special heat sensitive shrink wrap to the ends of the arms. This film is used by the electronics industry to wrap around bare wires, which is then shrunk to size using a hot air dryer. This material should be able to withstand the high temperatures that can occur in the vicinity of these lamps.

Caution Note No1
The doors are not secured to the lamp. On PAR cans, there is usually a clip at the top of the unit to ensure the doors cannot fall out. However, since video lights will normally not be tilted by more than 45 degrees up or down, I felt that designing a clamp would have added needless complexity to the project.

Caution Note No2
Both the lamp housing and the doors get very hot, even when using a 300 watt lamp.
Use oven gloves or similar insulated items when handling these units.

Step 6: Low Cost Barn Doors

The brackets and work lights can be obtained from most DIY stores. The doors CAN be purchased from theatrical or some dedicated music stores. However, they tend to be a little expensive! I have seen prices of $60 and upwards on US sites and about 25 ~ 30 Pounds Sterling on UK sites!!

Now this guide is about saving you money. So you need a good source. I recommend Thomann

Yes, this company is in Germany ... but it is actually cheaper to get the items delivered from here - at a price that`s unbelievable! At the time of writing, the barndoors were under NINE EUROS EACH. They weigh about 1kg each ... so you can get around 25 of them in a parcel (weight up to 31kg) sent to USA for just 30 EUROS. Of course, delivery to European countries is even less.

Perhaps you don`t want 25 barndoors. Well how about "topping up" with some PAR56 cans? These hold special reflector bulbs that can be obtained in wide flood or spotlight versions. These are the sort of lamps they use in discos to create very thin beams of light. (You will probably use the flood lamps more) These units are large, and weigh around 2kg each.

WARNING: They get very HOT in use

But lighting is not the only thing they sell. They sell microphones and drum kits, disco units and guitars - all at very keen prices. Remember, a parcel to America costs just 30 Euros for a parcel of 31kg in weight!! That`s around £25 ... but then European buyers will pay even less!! Visit the site, and I virtually guarantee you`ll lose track of time as you study all the goodies on offer.

And NO, I am not being paid to recommend this site (I wish I was!) Alas, their affiliate offer is rather poor offering just $10 for every $1,000 of business you send them. Still, you can`t have low prices and affiliate payments!

Please note: This is classed as "import", so UK residents may incur Import Duty imposed by Customs and Excise. US residents may have their own import duties to pay. Then there is VAT to add for UK residents. However, even with these extras added, the prices will still be well below commercial prices.

Reprinted from the original ebook created by Chris Brown:
To see our other DIY video project guides, please visit:
diy-video-gadgets

Comments

janekm (author)2009-01-28

There's no import duty to pay on goods travelling within the EU (so none for a UK customer buying from Thomann). VAT will be charged by Thomann (they're VAT registered in the UK so they charge the UK rate to UK customers, good given that's just been reduced to 15% compared to Germany's usual 19%...), though if you're a VAT registered business in the UK you may be able to get Thomann to zero-rate it in the same way a UK company would.

diy-video-gadgets (author)2008-05-18

Author Whoops: The link above is wrong. It should redirect to "diy-video-gadgets.com", and not "video-gadgets.com"

About This Instructable

9,205views

30favorites

License:

Bio: The website listed is a generic site as I have about seven active sites at this time. The above site will link to all of ... More »
More by diy-video-gadgets:Build a Low Cost Film / Video Boom MicrophoneAdd a barndoor to a worklight
Add instructable to: