discussion Keeping cylinders cylindrical

[Mickc1440]

Dear all
I'm looking for some advice on the best way to keep two part curved pieces in shape after gluing them together. My current battle is with aircraft drop tanks but I know this can be on anything such as exhausts and gun barrels etc. On all my recent attempts I've managed to flatten off the curve so its really noticeable. Any tips please?

 

[Tim Marlow]

Do you mean while cleaning up the seams? If that’s the case, clean them up at a forty five degree angle to the seam. If you clean it up perpendicularly across the seam or directly along it you risk flat spots.

 

[Mickc1440]

Do you mean while cleaning up the seams? If that’s the case, clean them up at a forty five degree angle to the seam. If you clean it up perpendicularly across the seam or directly along it you risk flat spots.

Yes Tim that's the problem, I guess I'm just too heavy handed but it seriously spoils the look of the finished parts. I was using flexible sanding pads which I thought would follow the contours.

 

[Tim Marlow]

Funnily enough, for that type of seam I prefer a hard backed abrasive. I have a couple of small blocks with wet and dry stuck to them for just that sort of job. After all, if you over fill the seam you are looking to remove high spots, not remove too much of the main structure.

 

[adt70hk]

Do you mean while cleaning up the seams? If that’s the case, clean them up at a forty five degree angle to the seam. If you clean it up perpendicularly across the seam or directly along it you risk flat spots.

45°.... Will have to give that a try next time.

Thanks Tim.

ATB.

Andrew

 

[wasdale32]

Have a look at these

https://ipmsuk.org/membership/products-seam-scraper/

 

[rtfoe]

I would sand and scrape with a sharp blade at the same time. Sometimes diagonally in an X pattern. Just go light and keep looking down the seam to see that the curve is maintained. Obviously gluing the halves as best you can helps less clean up and removing locating pins that misalign the fit is advisable.

Cheers,
Richard

 

[spanner570]

Much the same as Richard.
I usually remove any locating pins from cylindrical shapes (Including gun barrels) before gluing together and then gently clean up the seams with a sharp blade.

Ron

 

[The Smythe Meister]

A blade for me everytime

 

[Ian M]

This is one of those places good 'old fashion' poly glue like those from Revell or Humbrol. Enough to give a small ooze out of the joint, gentle clamping and leave it alone to harden.
The resulting bead of plastic after the glue can often be trimmed off with a sharp blade then a quick sand. I to prefer the harder sanding sticks. Right on the seam to take the edge down with a course grit then finish with a fine one. FOLLOW the curve and gently does it.

 

[Mickc1440]

Many thanks gents for the input and quite a bit to think about.

 

[scottie3158]

Have to agree with Richard and Ron. Then scrape with a blade at 45 deg across the joint and not down it to avoid flattening the area.

 

[Mickc1440]

I have a feeling now that when my next build gets posted certain parts will come under scrutiny :smiling: :smiling:

 

[Airborne01]

A blade for me everytime :smiling3:

Yup! A good sharp 15 blade, lightly and judiciously applied, whilst gently rotating/manoeuvring the offending item - followed by a gentle (like a virgin's kiss) swipe with a wet ultra-fine abrasive cloth! If all else fails buy a metal substitute!
Steve

 

[Mickc1440]

As a result of Mark’ recommendation I’ve purchased the ipms sets. Very nicely made just need to work out how to use them all