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I had read about the Hammer, at its ridiculously low price of £164 and thought that it must be a cheap Chinese offering of doubtful quality, then read it was actually made in Poland by a reputable manufacturer, so how on earth were they managing to produce it for that price.

Having just bought and now flown a Merlin at £600 it was a bargain too good to miss. No wonder they were on back order when I ordered and paid for mine.

It took a month to arrive. Apparently they just can't make enough of them - no surprise there.

The box arrived. It was pretty flimsy if I'm honest. I unwrapped it and examined the contents. The fuselage looks quite well made with carbon fibre reinforcement. Not sure I need to do any strengthening with extra carbon fibre - we will see.

Edited By Peter Garsden on 05/07/2015 22:42:35

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The wings are veneered polystyrene, so not a mouldie - hence the price.

The V Tail is balsa, and the wing is attached using 4 bolts.

I have read that it is possible to put balast in it, but at the moment, I can't work out where to put a ballast tube - any ideas?

I think I will cover the wings in 25gram fibreglass cloth then water based resin and either cover with Solarfilm or paint - not sure which yet.

The bits look comprehensive enough, but no connecting rods or clevises for the servos which is a bit odd, and not connectors for the tailplane. Must download the instructions and have a study.

This is a picture of what it should look like when it is finished.

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Hi Pete - I have one too ! Bought mine about 3 years ago from Rob at flying dog, and its still in the box..... somewhere!!"

I doubt it will make it to the building board this year if Im honest - not moved up the queue enough yet however, Ill be bookmarking this thread and following how you get on

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Well Tim -- I think this has potential, but I can see where the cost savings have been made. Still for £164 it is a steal whatever the state of play.

Initial thoughts

  1. I can't work out how to attach the clevis at the rear for the elevators to the snakes as what is supplied with the kit is very thin wire - less than 2mm which is what most clevises need - maybe a plastic attachment will work.
  2. There is no ballast tube. From what I have read it needs ballast, so I have bought a carbon ballast tube from T9 and am hoping to install it from the canopy backwards. I already have 19mm ballast for my Merlin so I hope I can use the same system. Will extend the plywood servo support backwards to hold the front of the tube and create a gutter shaped fibreglass support for it as I did with the Merlin on the other thread **LINK**
  3. I have bought some Hitec 125mgs and frames to install in the wing. Am planning to use the same plug system that was recommended with the Ideal ie a Video Computer 15 pin plug and socket. I will be using Savox 255 side by side in the fuselage. It's going to be a squeeze and I've no idea where the receiver is going to go yet - we will see.
  4. The fuselage is a bit flimsy so I am going to beef it up a bit, probably some carbon toe or some extra carbon somewhere. Also thinking of bracing the fuselage behind the wing with some balsa in the same way as I did with my Voltij which is still solid.
  5. I am not very happy with the way the tailplane just sticks on with glue or bolts on with plastic bolts, but can't see a way round it really. I think I will go with the bolt on method as in a heavy landing maybe the bolts will snap?
  6. No instructions again you have to download stuff from the manufacturer or Flying Dog's website. Am doing that now.

Edited By Peter Garsden on 06/07/2015 19:40:01

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Well, made a 5 minute start tonight. Nothing much. The wing is joined with a flat steel rod into a thin brass tube. Have managed to print and read the instructions, which considering it is probably a Polish translation are very good and comprehensive. the Flying Dog link wouldn't work for me so I went to the manufacturer's website where there were not only instructions which downloaded fine but also a schematic which helped a lot.

I have now worked out how to fit the ballast tube which is carbon and will fit my slugs. It is 400mm long and 20mm inside diameter. It will rest on the fuselage floor and the centre will be under the c of g. Think I will be able to get 10slugs in it a treat - same as the Merlin. Got a plan now.

So back to the wing. You have to blank off one end of the brass tube with fibreglass and allow the resin to cure. I couldn't work how to make the tube stay in position then remembered my plastic clamps which I have hardly ever used since I bought them 3 years ago from Blackburn Model supplies. So should be able to lift the hardened part from the plastic tomorrow morning.

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Forgot to wax the plastic sheet above so the fibreglass stuck to it but no worries as it just pulled off in a tear. It sanded back very easily thus blocking off the end of the brass box tubing.

Next job was to rough up the surfaces of the brass and steel bar and mix some 5 minute epoxy which was smeared on the ends so as to roughly secure the bar and brass box tubing.

I didn't have 2.4metres of length on the work bench so used the kitchen island which is 3.2metres long. No complaints as yet.

I made up a 60mm support for the dihedral, pushed in the support bar and tubing and left it to set first taping the wing halves together using masking tape.

Next job is to inject some slow setting epoxy into the gaps left round the bar and tubing with a syringe. Not looking forward to that.

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I've had my Hammer for a couple of years now and have found the fuse to be quite robust! But as you are adding a ballast tube and extra weight to wings in the form of 25g/m2 FG then perhaps adding some fuse reinforcement is advisable. You might also need a good stock of 4mm nylon wing bolts! Seriously though depending on which hole you're filling in your hangar you shouldn't be disappointed.

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I do have a whole album of Hammer construction photo's on here which might interest you but not sure how to add a link. You could try the link under my Avatar!

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Hello Peter. I completed my Hammer build earlier this year. I didn't fit a ballast tube but did fit an electric option in a way that leaves the motor and flight battery in situ even in pure glider form (just the prop and spinner are removed to allow the glider nose sheath to be fitted ). As a result, my Hammer weighs in at around 4lb. This doesn't give it racing pace but seems about right for general aerobatic flying which is what I wanted it for.

Some details of my build here, in case it helps

http://www.bartonhewsons.uk/home/modelflying/soarers/blejzykhammerpro.html

Trevor

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FWAL - thanks for that - I see you have a cross tail whereas I have a V Tail. Presumably you have just varnished your wings. I did read that there were two Hammers flying together up the Hole of Horcum and one wished he had put a ballast tube in like the other. The model also felt a bit light. I have worked out how I will fit it now so we will see. As for 4mm plastic bolts I presume you mean for the wing as now they use 5mm no doubt for this reason. Interestingly, my Top Model Ideal uses the same system but has 5mm steel bolts. When I asked if one could use plastic the answer was that they proably wouldn't be strong enough to withstand the force. My V tail screws on with 4mm plastic bolts.

Trevor - interesting - will try and look at your blog shortly. I did see the option for the motor but didn't think I would use it. I have a motor on my big hotliner, the Top Model Ideal so opted for the non electric version.

I think it wiill go better with some ballast, F3f planes usually do.

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Hi Peter

I have added about 200g of ballast on the CoG to my Hammer and it goes well. Those guys up North add up to 700g when fully ballasted and then it really motors.

Have you seen this thread when it comes to a neat way to load and lock your ballast: **LINK**

It's on the Hammer's little cousin the Mefisto and it's half way down the page.

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Well tonight and today I attempted to secure the wing steel rod and brass square tube. I was using a new tube of 5 minute epoxy which one smears on the bottom of the rod and tube. Unfortunately the hardener did not come out so the glue didn't set. So I tried again and there was not enough to sercure the rod, so thired time lucky. What a phaff.

So then it was time to fill the voids round the rod and tube with epoxy. Advisable to use 1 hour it said. I found some Araldite - even stronger. I decided to dilute it with meths - bad move as it was too runny. I also tried the syringe method as suggeted - didn't work as the tube got air into it and wouldn't squeeze through, so I abandoned that idea and decided to push it in with a paired down glue speader - worked img_20150708_210156.jpga treat. So now I am waiting for it to dry. I think I will put another layer in once the first layer is dry - will take overnight.

I had to block off the brass rube.with something to stop the epoxy from leaking inside, so I made a piece of balsa and covered it in mould anti release wax.

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Now is a good time to check whether any of the Gorilla glue has found its way into the flap hinges. Hopefully you will be okay since your hot wire cutter gives you more control over the depth of the hole than my scalpel and screwdriver hacking method!

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Trevor - no gorilla glue where not wanted. Know what you mean however as it oozed everywhere and had to be sanded back. Filled the gaps as intended though.

I decdided to cover the wings with 25gram fibreglass cloth and Eezecote the water based resin. Need quite a lot and have seen a debate which says Ronseal Hard Coats Floor Varnish is much cheaper.

I reckon that the varnish acts a bit like balsaloc and helps the film stick. Also it is going to be the same weight as paint?

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Have added the top sheet of fibreglass cloth now and the wing pin locators, which are not supplied with the kit remarkably, so I used up some left over short lengths of 4mm carbon rod. Will probably be OK as they are just intended to line up the wing halves when joining them.

I am going to use the circles of fibreglass cloth when cut out to line the bottom of the servo holes and to give a smooth surface to glue the servo mounting trays to. Am going to use some HS 125mg for the Ailerons and HS85mgs for the flaps as there is more depth. Also HS85mg's have better torque rating I think.

I think I will use some White Oracover on the wings and trim with some fluorescent orange and black - should look good, and will show up.

To finish the fibreglass cloth edges one just sands off the cloth. Have now given it another coat which will be enough with film on top.

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I have been considering how to decorate the wings in anticipation of finishing - still a long way off it is true, but dreaming is allowed.

I have decided to cover with Oracover and fluorescent orange/black trim, so needed a logo to go with it. I looked on the internet, found an aggressive font called nal_foughtknight and have recoloured a hammer clipart which I saw on one of the other bloggs. I will print out on my inkjet printer onto decal paper, then spray with varnish to seal it.

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It was quite difficult to line up the wing joining pins,, and I had to put some filler in the holes. It turned out I didn't read the instructions properly as it said drill the receiving hole first then the opposite one. I glued the male carbon rod and glued it first before drilling the second hold. Will know next time.

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